Daniel Marty

Abstract:

Abstract: Late Jurassic sauropod trackways from the Jura Mountains (NW Switzerland) and the central High Atlas Mountains (Morocco) are described and compared. Emphasis is put on track preservation and trackway configuration. The trackways are similar with respect to preservation and the pes and manus track outlines, but they show a large range of trackway configuration. Only one of the trackways reveals digit and claw impressions, and thus differences in trackway gauge and the position of pes and manus tracks are the most explicit characters for their distinction. The Late Jurassic to Early Cretaceous ichnotaxa <i>Brontopodus</i>, <i>Parabrontopodus</i> and <i>Breviparopus</i> are reviewed and a differential diagnosis is given for the trackways studied. The reference trackway of <i>Breviparopus</i> corresponds to one of the studied trackways of Morocco. <i>Parabrontopodus</i> and <i>Breviparopus</i> are considered to be both valid ichnotaxa, even though we recommend the latter to be formally erected based on better-preserved tracks than those currently exposed. The analysed trackways and ichnotaxa suggest that trackway configuration, notably trackway gauge (width), is not decisively influenced by extrinsic factors such as ontogenetic stage, locomotion speed and substrate properties. However, it cannot be excluded that it is related to other factors such as individual behaviour or even sexual dimorphism.

Abstract: This study concerns the formation, taphonomy, and preservation of human footprints in microbial mats of present-day tidal-flat environments. Due to differences in water content and nature of the microbial mats and the underlying sediment, a wide range of footprint morphologies was produced by the same trackmaker. Most true tracks are subjected to modification due to taphonomic processes, leading to modified true tracks. In addition to formation of biolaminites, microbial mats play a major role in the preservation of footprints on tidal flats. A footprint may be consolidated by desiccation or lithification of the mat, or by ongoing growth of the mat. The latter process may lead to the formation of overtracks. Among consolidated or (partially) lithified footprints found on present-day tidal flats, poorly defined true tracks, modified true tracks, and overtracks were most frequently encountered while unmodified and well-defined true tracks are rather rare. We suggest that modified true tracks and overtracks make up an important percentage of fossil footprints and that they may be as common as undertracks. However, making unambiguous distinctions between poorly defined true tracks, modified true tracks, undertracks, and overtracks in the fossil record will remain a difficult task, which necessitates systematic excavation of footprints combined with careful analysis of the encasing sediment.

Abstract: Since 2002 six dinosaur tracksites have been discovered by the «Palaeontology A16» on the future course of the Transjurane highway in the Ajoie district of the Canton Jura. These tracksites are systematically excavated prior to the construction of the highway. So far, over 4'000 dinosaur footprints including 280 trackways have been excavated and documented within three different time intervals of the Kimmeridgian. This indicates the presence of dinosaur populations, which lived on the northern margin of the Jura carbonate platform. The dinosaur assemblages revealed by footprints are composed of different size classes of both sauropod (quadrupeds, herbivores) and theropod (bipeds, carnivores) dinosaurs. The tracksites are of major importance for Switzerland's palaeontological heritage. In 2006, the Chevenez - Combe Ronde tracksite has been spanned by an additional bridge specifically built for this purpose. This is the first large palaeontological site in Switzerland, which is protected and made accessible by the construction of a highway. In May 2006 the Canton Jura decided to pursue the political discussion of a valorisation of the tracksites. A valorisation with a combined promotion of tourism, science and education might facilitate palaeontological excavations and research in the Canton Jura, once the construction of the highway will be accomplished.

Abstract:

Abstract: The Faciès Rognacien is a sequence of highly bioturbated and pedogenically modified palustrine carbonates that were deposited under oxic conditions around the Cretaceous-Tertiary (K-T) boundary in the northeastern Pyrenean foreland basin (SW France). The sedimentary structures and early diagenetic features identified (mottling, nodule formation, brecciation, pseudomicrokarst, cracking, charophytes, Microcodium) suggest deposition in a palustrine environment between the subarid and intermediate climate type. Sedimentological and paleoecological analysis enables us to distinguish two facies associations, the lacustrine pond facies and the freshwater marsh facies associations. The majority of the carbonates are attributed to the freshwater marsh facies. The lacustrine pond facies occurs only in isolated paleolows, and is identified on the basis of its paleobiological content (charophytes, ostracodes). This suggests that the palustrine carbonates of the Faciès Rognacien were deposited in a seasonal wetland (carbonate-producing freshwater marsh), rather than in the marginal zone of a large, shallow lake. In this wetland paleoenvironment, all carbonates underwent widespread pedogenesis, and small, ephemeral ponds are of limited distribution, most likely recording deposition in paleolows.

Abstract: In February 2002, a new dinosaur tracksite was discovered on public land on the future course of the �Transjurane� highway in Courtedoux, Canton Jura northwestern Switzerland. The Courtedoux tracksite is a �multithematical� geotope (JORDAN, 2002a), with an extraordinary scientific potential and it has the potential for development into one of worldʼs largest and most important sauropod tracksites (LOCKLEY, 2002). Since its discovery, the protection and the conservation of the site in situ was promoted by the �Section de paléontologie�. Simultaneously, the high level of scientific, media and public interest has proven the great scientific and educational value and the great potential for sustainable touristic use of the site. According to Swiss law, the site is a natural object of high scientific value and has to be protected from destruction, as, in Switzerland, heritage sites of national value are rated with the same level of significance as federal infrastructure projects, such as highways. Due to the favourable location of the site at one end of a viaduct, the site could be protected by the construction of an additional small highway-bridge. Such a building could provide ideal conditions for the conservation, scientific research and public viewing of the site.

Abstract: Die �Section de paléontologie�, gegründet im Februar 2000, ist ein Pilotprojekt in der Schweiz. Das Projekt ist in das kantonale Amt für Kultur (Office cantonal de la culture OCC) integriert und durch das Bundesamt für Strassen (95%) und den Kanton Jura (5%) finanziert. Das Mandat besteht in der Bergung, Dokumentation und wissenschaftlichen Auswertung des paläontologischen Kulturgutes auf der Linienführung der zukünftigen Autobahn N16 (Transjurane), welche Biel mit Delle verbindet (Figur 1). Der Arbeitsablauf lässt sich in mehrere Phasen gliedern. Während der ersten Phase (Prospektionsphase) werden mittels Feldbegehungen, Profilaufnahmen, geologischer Kartierung und Literaturrecherche die fossilreichsten Zonen auf der Trassee der Autobahn positioniert. Diese Zonen werden in der Folge unter Einsatz eines Baggers sondiert (Sondierungsphase). Schichten, in denen sich später paläontologische Flächengrabungen lohnen könnten, werden so genau lokalisiert. Nach Erstellen eines Konzeptes kann eine Grabung durchgeführt werden (Figur 3). Diese beginnt idealerweise 2-4 Jahre vor dem Autobahnbau, verzögert also die Bauarbeiten nicht. Nebst den Grabungen werden laufende Bauarbeiten überwacht, da auch dabei noch wichtige Funde zu Tage treten können. Im Extremfall kann eine Notgrabung veranlasst werden. Auf allen Grabungen werden Funde dokumentiert und wenn möglich geborgen. Zuletzt werden sie archiviert und wissenschaftlich ausgewertet. Durch einen solchen Arbeitsablauf hat die �Section de paléontologie� bis Ende 2003 auf der Trasse der Transjurane im Späten Kimmeridge 12 Horizonte mit Dinosaurierspuren an 3 Lokalitäten sondiert. Das erste Vorkommen wurde bei Courtedoux-�Sur Combe Ronde� im Februar 2002 entdeckt. An dieser Fundstelle finden sich Fussspuren von Dinosauriern auf mindestens 6 Schichtoberflächen innerhalb circa ein Meter mächtiger Plattenkalke. Diese können auf einer Fläche von nahe 1500 m2 freigelegt werden. Bisher wurde der Hauptfährtenhorizont (unterster Horizont) des Vorkommens auf einer Fläche von 650 m2 freigelegt (Figur 2). Darauf sind über 650 einzelne Trittsiegel von Dinosauriern sichtbar. Rund 400 lassen sich 2 Fährten von bipeden, karnivoren Theropoden und 17 Fährten von quadrupeden, herbivoren Sauropoden zuordnen (Marty et al., accepted a). Die anderen spurenführenden Horizonte können auf einer Fläche von ungefähr 900 m2 noch ausgegraben werden. Zusätzlich findet sich an der selben Lokalität ein weiterer Spurenhorizont circa 3 m im Hangenden der Plattenkalke. Das zweite Spurenvorkommen wurde im August 2003, bei Chevenez-�Combe Ronde� sondiert (Figur 3). Diese Fundstelle wird bis im Frühjahr 2004 ausgegraben. Es finden sich Fährten von juvenilen Sauropoden (Figur 4) und von kleinen Theropoden. Im Oktober 2004 wurde in Courtedoux-�Bois de Sylleux� ein weiteres Spurenvorkommen sondiert und teilweise freigelegt. Es handelt sich um dieselbe Einheit wie bei �Sur Combe Ronde� und bisher konnten 3 spurenführende Horizonte nachgewiesen werden. Auf den während der Sondierungsphase freigelegten Fläche finden sich kleine bis sehr grosse Trittsiegel von Sauropoden. Das Vorkommen wird ab 2004 ausgegraben. Nebst den Spurenvorkommen werden von der Section de paléontologie an mehreren Lokalitäten Flächengrabungen in marinen Mergeln und Kalken durchgeführt. Zur Zeit werden die Banné Mergel (Gygi, 2000) und mehrere Schichten innerhalb eines circa 10 m mächtigen Profils im Hangenden der Plattenkalke von �Sur Combe Ronde� abgegraben. Nebst marinen Invertebraten (Bivalven, Gastropoden, Ammoniten, usw.) finden sich auch Wirbeltierreste (Schildkröten, Krokodile, Fische). Die Spurenvorkommen lassen sich durch die Ammoniten auf das frühe Späte Kimmeridge datieren (Marty et al, 2002).

Abstract: In 2002 a new dinosaur tracksite was discovered in calcareous laminites of early Late Kimmeridgian age along the future course of the �Transjurane� highway in Courtedoux, Canton Jura, Northern Switzerland. The site has an extraordinary scientific potential, as the laminites, which have been deposited in an intertidal to supratidal environment, contain at least 6 track-bearing levels in a total thickness of about 1 m. The laminites are being systematically excavated by the �Section de paleontologie� over an area of approximately 1500 m2. So far the main track level has been uncovered over an area of about 650 m2, which reveals 2 trackways of theropods and 17 trackways of sauropods. The sauropod tracks are the smallest known in the Kimmeridgian so far, and the trackways belong to the ichnogenus Parabrontopodus, which has been revealed for the first time in Switzerland. The tracksite belongs to the �Middle Kimmeridgian megatracksite� sensu Meyer (2000), and represents the most important dinosaur tracksite in Switzerland, perhaps with the potential for development into one of the world's largest sauropod tracksites. It will be protected in situ underneath an especially constructed highway-bridge, thus offering opportunities for future research and the development of an interpretative center for education and tourism.

Abstract:

Abstract: Our review of the last interglacial (Marine Isotope Stage 5e) stratigraphic record from the Boiling Hole exposure in northern Eleuthera Island, Bahamas, revealed the occurrence of two vertically stacked shallowing-upward sequences of oolitic coastal deposits showing beach facies at about 3 and 6 m above mean sea level, respectively. These beach strata dip towards the bank interior and the upper one includes a paleosurface on top of an oolitic grainstone bed with a 2m long bird trackway. These fossil beaches correspond to two distinctive sealevel highstands during the last interglacial that could have possibly reached +5 and +8 m above modern datum, respectively, if estimates of regional subsidence are indeed correct. The bird footprints are the first reported occurrence of vertebrate trace fossils from the Bahama Archipelago. The track maker was probably an extant shorebird belonging to the Order Charadriiformes. Track preservation in an oolitic grainstone is remarkable and may be related to an early phase of halite cementation. Finally, the dip of the beach beds indicates that constituent grains were transported onto the island from the bank side by a westerly flux opposite to the modern sediment transport direction in the area.

Abstract: Im Februar 2002, zwei Jahre nach der Gründung der �Section de paléontologie�, wurden auf dem Trassee der zukünftigen Transjurane in Courtedoux die ersten Dinosaurierspuren entdeckt und nachfolgend ausgegraben. Das Spurenvorkommen von Courtedoux ist ein multithematisches Geotop oder ein Naturdenkmal im Sinne des Zivilgesetzbuches und des Bundesgesetzes über Natur und Heimatschutz. Es ist eines der weltweit bedeutensten seiner Art der Jurazeit (Lockley, 2002; Meyer, 2002), und verfügt über ein grosses wissenschaftliches, didaktisches und geotouristisches Potential (Jordan, 2002; Marty et al., accepted a). Zudem ist es bestens zugänglich und begehbar. Das Spurenvorkommen kann durch geringfügige bauliche Anpassungen der Autobahn geschützt werden. Mit einem Besucherzentrum oder Museum vor Ort kann die Fundstelle als Zentrum eines regionalen oder sogar überregionalen oder internationalen Geoparks fungieren. Das könnte Signalwirkung für die Zukunft der paläontologischen Forschung und den Geotopschutz in der Schweiz haben. Die �Section de paléontologie� führt unvermindert paläontologische Sondierungen und Grabungen durch. Weitere Spurenvorkommen konnten so bereits lokalisiert werden.

Abstract: Dinosaur tracks are biogenic, sedimentary structures and not body fossils or biological objects in the common sense. They result from the complex interaction of the kinematics of the trackmaker, its foot anatomy, and the substrate properties, and from taphonomic processes acting prior to the incorporation of the tracks into the sedimentary record. The objective of this work is an interdisciplinary study of a large sample of dinosaur tracks and trackways linking sedimentology with vertebrate ichnology, palaeontology, and palaeoecology. Excellent conditions are provided by the Late Jurassic (Kimmeridgian) Chevenez�Combe Ronde tracksite, which is one of several tracksites located on the future course of the Transjurane highway near Porrentruy (Canton Jura, NW Switzerland). Here, eight superimposed dinosaur track-bearing surfaces were systematically excavated level-by-level within a 0,65 m thick laminite interval, unearthing almost 1400 dinosaur tracks. The main track level, located at the base of the interval, is the most diverse ichnoassemblage composed of 14 trackways of tiny (Pes Length < 25 cm) and small (25 cm < PL < 50 cm) sauropods and 43 trackways of minute (PL < 10 cm), small (10 cm < PL < 20 cm), and medium-sized (20 cm < PL < 30 cm) bipedal, tridactyl dinosaurs. The main issues are: (1) identification of true tracks, undertracks, and overtracks, and their relationships with substrate properties, their link with the exposure index, and their utility in the reconstruction of the palaeoenvironment; (2) implications of the main track level ichnoassemblage for dinosaur behaviour, the terrestrial palaeoecosystem, and vertebrate ichnofacies; (3) relationships between variability in trackway patterns and configurations with locomotion speed, behaviour, and substrate properties as well as implications for locomotion capabilities; (4) Quantification and relevance of sauropod trackway gauge; and (5) interpretation of manus-dominated and pes-only sauropod trackways. The approach is first actualistic by studying human footprints and processes acting during their formation and preservation on modern tidal-flats. In these highly structured environments, microbial mats are ubiquitous, strongly facies-specific, and occupy a key position during and after footprint formation. Undertracks readily form in biolaminated sediment, whilst underprints and deep tracks are common in unlaminated, water-saturated sediment. Most consolidated vertebrate tracks are affected by taphonomic processes, including renewed and/or repeated growth of microbial mats leading to the formation of modified true tracks, internal overtracks (track fills), and overtracks. The sauropod tracks and the encasing laminite interval of the Combe Ronde site are then subject of detailed sedimentological and taphonomical analyses. This discloses the sediment properties at the time of track formation and reveals the processes modifying the tracks during subaerial exposure and integrating them into the sedimentary record. Track morphology, associated track features, and sedimentary features can be linked with the exposure index, identifying the palaeoenvironment as a supratidal flat not located in close proximity to a coastline. These flats were susceptible for track recording only during short periods after wetting due to a rainy period or due to occasional storms. Longer periods of subaerial exposure prior to burial are indicated by the presence of internal overtracks and/or overtracks, and rapid covering up is indicated by the lack of overtracks on top of tracks with large displacement rims. Cross-sections of sauropod tracks provide insight into the consolidation history of the substrate prior to track formation and into the walking dynamics of dinosaurs, confirming that sauropods put their hindfeet in a pronounced plantigrade way on the ground. The level-by-level superimposition of the studied surfaces enables to identify true tracks, undertracks, and overtracks. The best-defined true tracks (anatomical morphotypes) of the main track level are then used for ichnotaxonomy and trackmaker identification, and the detailed analyses of trackway parameters, including trackway gauge, provide insight into the locomotion capabilities of dinosaurs. The best-defined minute and small tridactyl tracks can be assigned to the ichnogenus Carmelopodus, extending it from the Middle Jurassic into the Late Jurassic. These tracks were likely left by a small theropod dinosaur similar in size to Compsognathus or Juravenator. The medium-sized tridactyl tracks of morphotype II exhibit some of the typical features of the ichnogenus Therangospodus (attributed to large and robust theropods) but also some of ornithopod ichnotaxa. The sauropod trackways show a wide range of patterns and configurations but are all medium- to wide-gauge. Therefore, they are assigned tentatively to the ichnogenus Brontopodus attributed to derived �brachiosaurid� or �titanosaurid� dinosaurs. The variability of the trackways reflects the general locomotion capabilities of the trackmakers and is an expression of individual walking style and behaviour, which may be related to substrate properties. Trackway patterns (the degree of manus overprinting by the pes) and different trackway configurations including trackway gauge are not only related to locomotion speed, and they provide no evidence of a relationship with ontogeny. The gauge of sauropod trackways can be quantified with the pes trackway ratio and the here defined [WAP/PL]-ratio (Width of the pes Angulation Pattern / Pes Length). Gauge is possibly related to the substrate and the behaviour of the trackmaker adapting to it, but this does not change the overall medium-gauge to wide-gauge appearance of the trackways. The manus-dominated and pes-only sauropod trackways of the Combe Ronde site are explained by trackmakers exerting more pressure on the manus than the pes, and by overprinting of the manus by the pes, respectively. The alignment of trackways on the main track level shows no evidence of a nearby shoreline and of interactions between the different groups of dinosaurs. It indicates gregarious behaviour amongst tiny and small sauropods, and suggests that minute and small bipedal dinosaurs were frequent visitors on the supratidal flats. The ichnoassemblage of the main track level is the first one found in the Jura Mountains displaying abundant minute and small tridactyl tracks. This is also typical for the other Ajoie ichnoassemblages, which further exhibit tracks of tiny to large (up to 1,1 m PL) sauropods, and tracks of medium-sized to large (up to 0,8 m PL) bipedal dinosaurs. Sauropod trackways include narrow-gauge and wide-gauge trackways indicating the presence of �basal� and derived sauropods. This suggests that dwarfed insular animals can be excluded as trackmakers of the tiny and small sauropod trackways of the Ajoie ichnoassemblages and the Combe Ronde tracksite and that the Jura carbonate platform was connected with the landmasses of the London-Brabant Massif and the Massif Central during periods of emersion. Dinosaurs used the Jura carbonate platform for the establishment of in situ, predominantly saurischian dinosaur populations, but also as a migration corridor between the massifs. Because the Ajoie ichnoassemblages are dominated by small tridactyl tracks, they differ from other Jurassic tetrapod ichnofacies in carbonate settings, notably from the Brontopodus ichnofacies. In the case of those ichnoassemblages commonly attributed to the Brontopodus ichnofacies, the lack or rareness of small tridactyl tracks may indicate the absence of small trackmakers in those palaeoenvironments or unsuitable conditions for the formation and preservation of small tracks. This study highlights the benefits of systematic and interdisciplinary analyses of dinosaur tracks, which disclose variations related to behaviour and to differences in substrate. This allows recognizing anatomical morphotypes and trackway configurations representative of typical trackmaker behaviour. The latter can then also be used in ichnotaxonomical classification. Similar approaches should be in the focus of future work and performed on the other tracksites and ichnoassemblages of the Ajoie. Together with the evidence from other tracksites of the Jura Mountains, this will contribute towards a better understanding of the terrestrial palaeoenvironments and palaeogeography, and of dinosaur palaeoecology and palaeobiogeography on the Jura carbonate platform.

Abstract:

Abstract: In the Canton Jura (NW Switzerland), the Palaeontology A16 since ten years systematically excavates body fossils and dinosaur tracksites prior to the construction of the highway A16. Four Late Jurassic (Kimmeridgian) intervals, each with several superimposed track-bearing levels, were excavated level-by-level on six tracksites situated on the future course of the highway. This revealed over 40 ichnoassemblages with 8�930 tracks including 222 sauropod trackways and 244 trackways of tridactyl bipedal dinosaurs, mainly attributed to theropods. The tracks were documented with standard ichnological and state-of-the-art 3D imaging technologies (laserscanning, photogrammetry). Sauropod and tridactyl tracks both vary from very small (10 cm pes length for sauropods; 6 cm for tridactyl tracks) to huge (115 cm for sauropods; 75 cm for tridactyl tracks), and different size classes and morphotypes are commonly associated on single ichnoassemblages. Trackways are up to 115 m long exhibiting different patterns and configurations, also along single trackways. These rich dinosaur ichnoassemblages give important insights into the otherwise poorly-known Late Jurassic dinosaur fauna of the Jura carbonate platform. This talk focuses on recent discoveries and results regarding ichnotaxonomy, palaeobiology and palaeoecology, and discusses future research directions. Furthermore outlined are the importance of the tracksites as natural, palaeontological heritage and implications for geoconservation and construction of the highway. So far, one tracksite was protected by the construction of an additional highway bridge. Discussions concerning the future (coveringup or protection by an additional highway bridge) of two other sites (one over 4000m2 in size) are currently under way at federal level.

Abstract: We report here on the discovery of new sauropod and theropod footprints from the middle and upper part of the Hauptdolomit Group (HDG; Mid to Late Norian) from the Upper Austroalpine Ela Nappe in the Natural Park Ela (Canton Graubünden; South-eastern Switzerland). Field studies and aerial surveys in 2009 revealed trampled surfaces in the middle part of the HDG (Late Alaunian to Early Sevatian) at two different locations that display rounded footprints with no signs of digits and can therefore be assigned to advanced sauropods. Close to the summit of Piz Mitgel (3127 m.a.s.l.), the uppermost part of the HDG displays a surface with well-preserved prosauropod pes prints and small- to medium-sized tridactyl footprints of theropod affinity. The summit of the Piz Ela is formed by steeply inclined, east-dipping bedding planes (816 m2) of the higher of part of the HDG with three vertebrate footprint levels. The lowermost surface shows several imprints of small theropods (?Grallator). The intermediate level (main surface) exhibits a long trackway with large tridactyl footprints with a pes length of about 33 cm, which can be assigned to the ichnogenus Eubrontes. Furthermore, a trackway with large footprints of a bipedal animal is present on the same level. The highest level, just below the summit, shows tridactyl tracks of small theropods and faint, large, rounded imprints that were most probably left by prosauropods. Higher up in the stratigraphic sequence at the boundary between the HDG and the overlying Kössen Formation (Sevatian), we found a dolomitic layer that shows a trackway with deep and possibly tridactyl imprints with mud rims of a bipedal animal. Up to now, seven levels with dinosaur tracks have been detected in a stratigraphic range spanning the Norian (Alaunian) to Late Rhaetian. The large theropod footprints attributed to the ichnotaxon Eubrontes reported here and those from the Swiss National Park together with the record from the coeval Dolomia Principale of the Tre Cime di Lavaredo (? Tuvalian; Dolomites, Italy) are the oldest unequivocal evidence of very large theropod dinosaurs in the Triassic. They predate the fossil remains of Liliensternus liliensterni from the Late Norian Knollenmergel of Southern Germany. If, the presence of footprints of advanced sauropods can further be substantiated these tracksites will become a key-element for the reconstruction of the evolutionary scenarios of saurischian dinosaurs developed in the last few years.

Abstract: In 2008 and 2009, the Béchat Bovais tracksite, located on the future course of the A16 highway (Canton Jura, NW Switzerland), was excavated over a surface of more than 4000 m2. On level 515, 2100 dinosaur tracks were uncovered and 28 sauropod trackways identified and documented by means of classical ichnological techniques, laser scanning, and photogrammetry. Layer 515 is a 5-15 cm thick, calcareous marl and its bedding plane (level 515) is a palaeosurface characterized by the presence of a dense network of reddish Thalassinoides burrows and true tracks with a wide range of morphologies indicating that substrate properties were not uniform across the site. Generally, on the underlying, desiccation-cracked level 510, no or only very shallow and faint undertracks are visible, indicating that level 510 was already well indurated at the time of track formation on level 515. Level 510 only broke occasionally under the pressure of the sauropod feet, leading in some places to the formation of deep tracks with steeply inclined track walls. Pes tracks are oval in shape, longer than wide, only rarely exhibit digit and never claw impressions, and their mean length and width vary from 35.8 to 59.3, and 27.4 to 45.4 cm, respectively. Manus track morphology varies from horseshoe-shaped over semi-circular to sub-circular without any evidence for pollex claw impressions. Manus imprints are always wider than long, and their mean length and width varies from 8.5 to 28, and 20.9 to 34.3 cm, respectively. Many of the trackways show different patterns and configurations, and marked distinctions also occur along single trackways (e.g. changes: from pes/manus to pes-only, in relative position of pes and manus tracks, in trackway gauge, in track rotation). Two extraordinary long and parallel trackways (S18 with 115 m, S19 with 105 m) show several small turns. The mean ratio between the width of the angulation pattern and the pes length characterizes 10 trackways as narrow, 9 as intermediate, and 9 as wide gauge. However, along several trackways (e.g., S18, 19, 21) these values change between narrow and wide over a couple of steps and demonstrate that these two locomotor styles could have been used by one and the same sauropod trackmaker. The long, continuous sauropod trackways of Béchat Bovais can be used for detailed studies on the environmental and taphonomical controls of track geometry and morphology, and they may provide important new data on the habitual locomotor characteristics of sauropods such as unsteady locomotion and changes in locomotor behaviour. Locomotor variation within ichnospecies can be addressed statistically, and ontogenetic effects of size on locomotor function can be analyzed.

Abstract: Unequivocal signs of emergence occur throughout the Late Jurassic, Kimmeridgian Reuchenette Formation of the Swiss Jura platform. Foremost of these are about 30 dinosaur tracksites that have been described from several localities and at least 5 stratigraphic intervals from NW Switzerland. The footprints indicate in situ populations of herbivorous and carnivorous dinosaurs on the Jura platform. This implies that a vegetational cover and consequently soils must have existed. Nonetheless, to date no palaeosols have been documented from the Late Kimmeridgian succession and no proof of soil formation has been presented. A Mediterranean climate is presumed to have prevailed on the carbonate platform during the Kimmeridgian. Typically, terra-rossa type soils should form on limestone under such climatic conditions and their formation should lead to karstification and iron-hydroxide impregnation. Two conspicuous, iron-impregnated, flat surfaces, from two intervals have been studied in detail to reconstruct their formation history. Different lines of evidence point to emersion and temporary formation of a soil cover over these beds. Although no root traces have been recorded, aragonite dissolution, formation of micritic meniscus cements, minor karstification and erosion all point to emersion of the surfaces and potential covering with soil. Subsequent re-flooding of the platform led to erosion of the soil cover wave cutting and re-deposition of clays and organic matter in shallow intra-platform lagoons. Such erosive events may partially explain the eutrophication of the system observed up-section of these surfaces. Due to coastal erosion large amounts of nutrients were mobilised and introduced into the platform waters, leading to a partial inhibition of the carbonate factory and the formation of mass accumulations of suspension-feeding molluscs.

Abstract: Sauropod trackways are generally classified according to their trackway width as narrow- and wide-gauge, and these categories are thought to have been left by basal (Diplodocidae) and more derived (Brachiosauridae and titanosauriform) sauropod dinosaurs, respectively. Nonetheless, a quantification of trackway gauge was only recently proposed by Romano et al. (2007) introducing the pes trackway ratio and by Marty (2008) introducing a ratio between the width of the pes angulation pattern and the corresponding pes track length. Narrow-gauge sauropod trackways from Morocco assigned to the ichnogenus Breviparopus DUTUIT & OUAZZOU 1980 do � contra all published outline drawings (e.g., Dutuit & Ouazzou, 1980; Ishigaki, 1989) � not show any evident toe or pollex impressions (Meyer & Monbaron, 2002; Belvedere, 2008). Depending on their preservational state, those from Switzerland may exhibit toe and/or claw impressions, and they are assigned to Parabrontopodus LOCKLEY, FARLOW & MEYER 1994 (e.g., Marty et al., 2003). Here, we compare Late Jurassic narrow-gauge trackways of different size classes from continental siliciclastic deposits of the central High Atlas and from carbonate-platform tidal-flat deposits of the Jura Mountains with respect to track preservation, track morphology, and trackway configuration (notably gauge). In doing so, we will highlight the influence of substrate properties, trackmaker behaviour (e.g., locomotion speed), and ontogenetic stage of the trackmakers on track morphology and trackway configuration. Finally, we will discuss the validity of the two ichnogenera, and � because Breviparopus may be restricted to the Gondwanan realm � their use in palaeo(bio)geographical reconstructions around the Tethys during the Middle to Late Jurassic.

Abstract: A new hypothesis is proposed that attempts to explain the genesis of several key phenomena such as: mass accumulations of nerineoids and oysters, hardgrounds and marls as well as signs of emersion, that are so characteristic for the Kimmeridgian succession of the Swiss Jura Mountains. Based on circumstantial evidence from two different maximum flooding surfaces, masked evidence of emersion and soil formation has been identified. During times of regression large parts of the Late Jurassic European carbonate platform emerged. Evidence for these recurrent periods of emergence in the form of dinosaur trackbearing intervals, tidal laminites, birdseyes, and beach lamination is abundant throughout the Kimmeridgian succession. The fresh water associated with these newly emerged areas initially dissolved the aragonitic components in the carbonate sediments and precipitated cements, thus leading to an early diagenetic consolidation. Following a new line of evidence for the genesis of terra rossa recently put forward by Merino and Banerjee (2008) and Meert et al. (in press), possible candidates for sub-soil rock surfaces are identified. Terra rossa is the typical soil-cover on carbonate rocks in Mediterranean type climate zones such as have been proposed for the Late Kimmeridgian (Abbink et al., 2001). Terra rossa soils have been shown to form principally by replacement of carbonate by authigenic clay minerals at a reaction front at the soil-rock interface. This process leads to corrosion and karstification of the underlying limestone. Due to the buffering effect of the carbonate, iron oxides and hydroxides are preserved, which encrust and impregnate the reaction front. By these means soils can accumulate with a speed of 25 cm / 10�000 years. These soils potentially permit a vegetation cover to become established on the emerged part of the platform, which in turn can sustain diverse populations of dinosaurs. Fossilized remains of this ancient flora, especially large pieces of wood, have lately been recovered from the lower Virgula marls near Porrentruy (Canton of Jura). Surfaces showing iron hydroxide impregnation, microkarst formation, dissolution of aragonitic components, corrosion, and negative excursions of the δ13C and δ18O isotope values due to the exposure to soil gas and fresh-water influence, respectively, are proposed to resemble the metasomatic front of the bedrock underlying these ancient terra rossa covers. These sequence-boundary deposits, however, are masked during the subsequent transgression. Rising sea level erodes the soil cover and vegetation, leaving only the ironhydroxide impregnated and microkarstified bedrock in evidence. The previously consolidated rocks are consequently intensely bored and encrusted. The organic-rich soil is flushed into the shallow waters of the platform where it forms the food basis for the suspension-feeding nerineoids in the high-energy zone. The clays are washed past the high-energy zone and finally are deposited in the deeper parts of the platform where they form the food basis for the small oysters Nanogyra (BEURLEN, 1958), which are abundant in the conspicuous, dark, organic-rich Virgula marls.

Abstract: Sauropod trackways from the Late Jurassic of NW Switzerland vary between narrow-gauge and very wide-gauge when the pes trackway ratio of Romano et al. (2007) and the ratio introduced by Marty (2008) between the width of the pes angulation pattern and the corresponding pes length (i.e., [WAP/PL]-ratio) are applied. So far, studied trackways include several narrow-gauge and one very wide-gauge trackways from a single tracklevel and medium-gauge to very wide-gauge trackways from another slightly older tracklevel. Marty et al. (2003) assigned the narrow-gauge type to the ichnogenus Parabrontopodus based on typical trackway characteristics (i.e., pronounced narrow-gauge, strong heteropody, outwardly rotated manus), later on Marty (2008) tentatively assigned the medium-gauge to very wide-gauge trackways to the ichnogenus Brontopodus because of their clearly wider gauge. However, the pes and manus tracks of all studied trackways, even though most of them are not very well preserved, have a very similar morphology: pes tracks longer than wide, oval in shape, and occasionally exhibiting digit impressions; manus tracks (if undeformed by the subsequent pes) wider than long, semicircular or slightly horseshoe-shaped, and without evidence for a claw impression on digit I. Apart from the marked difference in gauge, they further exhibit a similar general trackway configuration: strong heteropody, pes and manus rotated outwards, manus showing a higher outward rotation than pes, and centres of manus tracks being placed farther away from the trackway midline than those of the pes tracks. Therefore, the assignation of the studied trackways to the two distinct sauropod trackway types narrow-gauge (e.g., Parabrontopodus, Breviparopus) and wide-gauge (e.g., Brontopodus), based on differences in gauge alone, is problematic. We assume that the gauge of the studied trackways is not only related to the variable posture of different taxa (basal and more derived sauropods), but it may also have been influenced by other parameters such as substrate consistency, behaviour, speed or ontogenic stage. We plan to analyze all (currently 177) sauropod trackways including well-preserved tracks with anatomical details (i.e., digit and claw impressions) of NW Switzerland in a consistent way, to make preservational and sedimentological analyses, and to compare them with other known sauropod ichnotaxa, in order to clarify their ichnotaxonomical assignation.

Abstract: Since 2002, the Palaeontology A16 has excavated dinosaur tracksites near Porrentruy along the future course of the Transjurane highway A16. This resulted in the development of a complex excavation-, documentation-, and protection-methodology of dinosaur tracksites. First, tracksites are located by geological surveying followed by palaeontological prospecting with shovel excavators. Large-scale excavations are then planned and scheduled in agreement with the civil engineering office prior to the construction of the highway. The tracks are found on multiple superimposed palaeosurfaces within horizontally-bedded laminites of Late Kimmeridgian age, which accordingly have to be excavated level-by-level. At the beginning of an excavation, as much overburden as possible is removed with the aid of shovel excavators. Within the laminites, the track-bearing levels are then excavated and cleaned with hand tools, a time-consuming and difficult affair. Tracks are then searched for, identified, and whenever possible attributed to trackways. This includes analyses at night with oblique lighting, indispensable to find and study small tracks and track details. Simultaneously, all tracks are outlined with black chalk and labelled on the surface itself using specified acronyms. Subsequently, tracks and trackways are analyzed and described, and their parameters measured in a consistent fashion and gathered in a database. They are also photographed including stereoscopic photographs of selected tracks. Further, macrosedimentary features (e.g., desiccation cracks, ripple marks) are analyzed and the encasing sediment is logged and sampled. Afterwards, a geo-referenced 2x2 meter grid is installed on the surface and tracks and normal faults are drawn at a scale of 1:10 or 1:20. These drawings are vectorized in the office and assembled in a map. As outline drawings represent one person�s simplified interpretation of a complex three-dimensional object, the most important palaeosurfaces are likewise documented with 3D imaging techniques using high-resolution laser scanning and extreme close-range (2-10 m from camera to object) photogrammetry. These are merged in a virtual 3D model, on the basis of which tracks and trackways can easily be vectorized and their parameters measured in CAD software, if previously they were labelled and outlined with chalk. Similarly assembled data can later also be integrated into a GIS database. If a surface is going to be destroyed or exposed to weathering after excavation the 3D documentation is the most accurate way to document its original state, especially if applied together with complementary, classical illustrative and descriptive techniques as well as replicas. Consequently, future generations of researchers will have access to virtually the same database. Nonetheless, judging by our own experience, the 3D methods cannot fully replace careful observations and descriptions of the actual tracks in the field because the interpretation of small tracks or track details (e.g., digital pads, claws, skin impressions), poorly-preserved tracks, and/or crossing trackways (track interferences) is a difficult and subjective task done at best on the original specimens. Also, 3D methods are expensive and cannot always be applied. Another drawback is that adequate safeguarding of the imaging data for posterity may be difficult to guarantee. After their documentation, the most important tracks and trackways are either recovered as slabs or replicated, and then the underlying level is excavated. Such level-by-level excavation and documentation offer important insight into the formation, taphonomy, and preservation of tracks, notably the identification of undertracks, true tracks, and overtracks. At the end of an excavation recovered slabs, samples, and replicas are archived, and the documentation (e.g., photographs, track parameters, etc.) is assembled in a database (collection and documentation management). The main track level of the Transjurane tracksites is commonly located at the top of massive limestone and at the base of laminites. Consequently, it cannot be removed and will be either covered or (partially) destroyed by the construction of the highway. The importance of a tracksite has to be evaluated �in context� based on abundance, quality, and uniqueness of the tracks. Whenever possible it has to be preserved as a geotope in situ. Actually, one tracksite is already preserved for posterity by the construction of an additional highway bridge.

Abstract:

Abstract: This study is based on dinosaur tracks from the Swiss Jura Mountains, excavated on multiple superimposed palaeosurfaces located within Late Jurassic (Kimmeridgian) biolaminite intervals. The approach is first actualistic by studying processes acting during the formation and taphonomy of human footprints on tidal-flats, notably the stabilizing role of microbial mats. When compared with these recent prints, dinosaur tracks and the encasing sediment provide insight into walking dynamics, properties of the substrate, processes modifying and preserving tracks, consolidation history, and they identify true tracks, undertracks, and overtracks. These observations can be linked with the exposure index and suggest that the palaeoenvironment was a supratidal flat. Trackway configuration (e.g. gauge) and patterns (degree of manus overprinting) are quantified and analyzed. Their variability is an expression of locomotion capabilities related to walking style and speed, behavior, and substrate properties. Manus-only and pes-only sauropod trackways are explained by animals exerting more pressure on manus than pes, and to overprinting of manus by pes. Sauropod trackways with similar track morphology vary from medium- to wide-gauge (not clearly related to speed and ontogeny) challenging the traditional classification of sauropod trackways. Nonetheless, wide-gauge trackways are tentatively assigned to Brontopodus and narrow-ones to Parabrontopodus. Small (i.e. < 0.2 m long) tridactyl tracks are assigned to Carmelopodus (extending this ichnogenus into the Late Jurassic), and larger (i.e. > 0.2 m long) ones to Therangospodus. Trackway orientation and alignment indicates gregarious behavior amongst sauropods, and the common presence of small bipedal dinosaurs on supratidal flats. Small tridactyl and small (i.e. < 0.3 m) sauropod tracks are abundant, but large tridactyl (up to 0.8 m) and sauropod (up to 1.2 m) tracks are also common. Size-frequency distributions suggest the establishment of in situ, saurischian-dominated populations on the Jura carbonate platform, which consequently was regularly connected with the neighboring massifs and could also serve as a migration corridor.

Abstract: Recently, an increasing number of investigations comparing fossil and modern microorganisms highlighted the role of microbial mats in the formation of minerals and diagenetic processes leading to the development of sedimentary rocks including lithographic limestones and trace fossils. More specifically, on recent tidal flats, the sporadic growth of microbial mats alternating with carbonate precipitation may lead to the formation of biolaminated sediments, where vertebrate tracks (true tracks, undertracks, overtracks) are easily preserved (Marty et al. 2009). However, because microbial mats are mainly composed of extracellular polymeric substances (EPS) containing over 70% of water, the former presence of microbial mats in the fossil record can only with electron microscopy be proven unambiguously (Pacton et al. 2007). This study is based on Late Jurassic (Kimmeridgian) dinosaur track-bearing laminites from NW Switzerland near Porrentruy, which formed on tidal flats of the Jura carbonate platform (Marty 2008). Macrosedimentary structures (i.e., dinosaur tracks, desiccation cracks, ripple & wrinkle marks) of superimposed palaeosurfaces were documented and analysed and a high-resolution microfacies analysis was carried out. Of selected samples the total organic carbon content was determined by Rock-Eval pyrolysis, and mineralogical (including clay minerals) analyses were performed by standard X-ray diffraction. The organic matter (OM) was then isolated from the mineral fraction using a standard palynological preparation technique in order to analyse it on thin sections with optical microscopy using natural light and blue-light fluorescence, and on ultrathin sections with transmission electron microscopy (TEM). The former presence of microbial mats is suggested by the stromatolithic appearance of the laminites in the field; cryptmicrobial lamination and fenestrae in thin sections (i.e., a laminated alternation of OM and minerals); polygonal desiccation cracks, pustular nodules, and wrinkle marks on palaeosurfaces; and by associated track features such as (internal) overtracks. TEM observations show heterogeneous OM mainly composed of a more or less fluffy alveolar network corresponding to exopolymeric substances (EPS), sometimes of �curly� and ovoid bodies with thick membranes corresponding to bacterial and algal cell walls, and accessorily of complex fibrous structures with a strong contrast and characteristic lamellae indicating terrestrial fragments (plants). Further, ultralaminae displaying diffuse outlines and a relatively small thickness (80 nm) have also been observed. According to the classification of Pacton et al. (2008) they can be attributed to bacterial cell walls indicating a low degradation level in the OM cycle. This evidence suggests that the laminites were mainly formed by the sporadic growth of photosynthetic microbial mats occasionally incorporating terrestrial plants. We conclude that the studied laminite intervals formed in a tidal flat environment subjected to desiccation and rehydration (due to a regularly or episodically covering with shallow water) allowing the growth of microbial mats and hence the formation and preservation of dinosaur tracks. Today, such conditions are typically observed on higher intertidal to supratidal flats. Consequently, the palaeoenvironment of the laminites from NW Switzerland was clearly more terrestrial (i.e., characterized by a higher exposure index) when compared with the Kimmeridgian to Tithonian (sub)lithographic limestones from Cerin (shallow lagoon to intertidal; Gaillard et al. 1994), Orbagnoux (shallow lagoon; Tribovillard et al. 1999), and Solnhofen (deeper lagoon; Seilacher 2008).

Abstract:

Abstract: Since 2002, the Palaeontology A16 excavates dinosaur tracksites near Porrentruy along the future course of the Transjurane highway A16 (Marty et al., 2007). This resulted in the development of a complex excavation-, documentation-, and protection-methodology of dinosaur tracks and tracksites. First, tracksites are located by geological surveying followed by palaeontological prospecting with shovel excavators. Large-scale excavations are then planned and scheduled in agreement with the civil engineering office over one to several years prior to the construction of the highway. The tracks are found on multiple superimposed palaeosurfaces within horizontally-bedded biolaminites of Late Kimmeridgian age, which accordingly have to be excavated level-by-level. At the beginning of an excavation as much overburden as possible is removed with the help of shovel excavators. Within the biolaminites, the track-bearing levels are then excavated and cleaned with hand tools. This is often a time-consuming and difficult affair, because of normal faults displacing levels or because levels are amalgamated and cannot be followed laterally. Tracks are then searched for, identified, and wherever possible attributed to trackways. This includes analyses at night with oblique lighting, indispensable to find and study small tracks and track details. Simultaneously, all tracks are outlined with black chalk and labelled on the surface itself using specified acronyms. Subsequently, the tracks and trackways are analyzed and described, and their parameters are measured in a consistent fashion and gathered in a database. They are also photographed including stereoscopic photographs of selected tracks. Further, macrosedimentary features (e.g., desiccation cracks, ripple marks) are analyzed and the encasing sediment is logged and sampled. Afterwards, a georeferenced 2x2 meter grid is installed on the surface and tracks and normal faults are drawn at a scale of 1:10 or 1:20. These drawings are vectorized in the office and assembled in a map. Because outline drawings represent one person�s simplified interpretation of a complex three-dimensional object, the most important palaeosurfaces are likewise documented with 3D imaging techniques using high-resolution (in the order of 1-2 mm) laser scanning and extreme close-range (2-10 m from camera to object) photogrammetry. These are merged in a virtual 3D model, on the basis of which tracks and trackways can easily be vectorized and their parameters measured in CAD software, if previously they were labelled and outlined with chalk. Similarly assembled data can later also be integrated into a GIS database. If a surface is going to be destroyed or exposed to weathering after excavation the 3D documentation is the most accurate way to document its original state, especially if applied together with complementary, classical illustrative and descriptive techniques as well as replicas (see also Lockley & Matthews, 2007). Consequently, future generations of researchers will have access to virtually the same database. Nonetheless, judging by our own experience, the 3D methods cannot fully replace careful observations and descriptions of the actual tracks in the field because the interpretation of small tracks or track details (e.g., digital pads, claws, skin impressions), poorly-preserved tracks, and/or crossing trackways (track interferences) is a difficult and subjective task made at best on the original specimens. Also, 3D methods are expensive and cannot always be applied. Another drawback is that adequate safeguarding of the imaging data for posterity may be difficult to guarantee. After their documentation, the most important tracks and trackways are either recovered as slabs or replicated, and then the underlying level is excavated. Such level-by-level excavation and documentation offer important insight into the formation, taphonomy, and preservation of tracks. Notably the identification of undertracks, true tracks, and overtracks, which is important for the correct ichnological and palaeoecological interpretation of the tracks (Marty, 2008). At the end of an excavation recovered slabs, samples, and replicas are archived, and the documentation (e.g., photographs, track parameters, etc.) is assembled in a database (collection and documentation management). The main track level of the Transjurane tracksites is commonly located at the top of massive limestone and at the base of biolaminites. Consequently, it cannot be removed and will be either covered or (partially) destroyed by the construction of the highway. The importance of a tracksite has to be evaluated �in context� based on abundance, quality, and uniqueness of the tracks. Whenever possible it has to be preserved as a geotope in situ. Actually, at least two tracksites can be preserved for posterity by the construction of additional highway bridges. These outstanding results of cooperation between engineers and palaeontologists are the basic conditions for a public accessibility of the tracksites, managed and financed by the Canton Jura, once the highway will be finished.

Abstract: The Banné Member was defined by Gygi (2000). Originally called �Marnes à Ptérocères� (Ptérocère=Harpagodes oceani), this member was described by Jules Thurmann as �Marnes du Banné� (Thurmann & Etallon 1864). The Banné Member is a sequence of about 10 meters thick of highly fossiliferous calcareous marls and marly limestones deposited in a shallow water lagoon. Most of levels are so rich in marine invertebrates (mainly Bivalvia, Gastropoda and Brachiopoda) that they can be considered as shell beds. Ammonites (Prorasenia sp.) date the Banné Member to the late Early Kimmeridgian (Divisum zone, ca. 152 My) and the time interval of its sedimentation, based on sequences stratigraphy and cyclostratigraphy analysis (Colombié 2002), corresponds to about 0.2 My. Between 2001 and 2007, the Palaeontology A16 operated systematic excavations along the future course of the Transjurane highway (A16) in the Banné Member near Porrentruy (Canton Jura, Switzerland). Based on bulk sampling and detailed documentation of surface of one square meter, species richness, abundance and commonness were used to characterize the vertical evolution of the invertebrate assemblages. Larger surfaces were also excavated in order to improve the completeness of the fossil record, including uncommun taxa (echinoids, ammonites, fishes, turtles and crocodilians). A systematic sampling was performed for mineralogical and sedimentological analyses using X-ray diffraction and microfaciès descriptions. The first faunal list of bivalves defined about 100 species (Hicks 2006; Richardt 2006). The surface documentations underline a significant vertical evolution of the invertebrate assemblages, marked by an increasing of the diversity. Moreover, clay mineral analysis show a progressive decrease and then the disappearing of kaolinite in the middle part of the sequence. This study is actually in progress. It seems that we can interpret the preliminary results as a local climatic change, extended to the whole Banné Member distribution, maybe a cooling event combined with hydrodynamic changes. A special effort will be done in statistic analysis to better understand the faunal diversity evolution. The aim is to characterize the ecological evolution of the fauna of the Banné Member and the associated mineralogical changes in a high resolution stratigraphical frame and to correlate this changes with other regional localities of the same time interval.

Abstract: The exposure index links typical sedimentary and organic features to the hydroperiod (i.e., days per year on which the ground surface is covered with water) and is useful in the classification of tidal-flat subenvironments (Ginsburg et al., 1977). Observations made on human footprints in recent tidal-flat environments demonstrate that microbial mats, which are ubiquitous on modern tidal flats and strongly facies-specific (e.g., Noffke et al., 2001), play a crucial role during and after the formation of footprints. Undertracks readily form in biolaminated sediment, and footprints are subjected to a number of taphonomic and sedimentary processes, in which renewed and/or repeated growth of microbial mats is commonly involved (Marty et al., 2008). Sediment consistency and growth parameters of the microbial mats are directly linked to the exposure index and control the consolidation of unmodified true tracks, the formation of modified true tracks and (internal) overtracks, or the burial of true tracks without the formation of overtracks. Similar processes are inferred from detailed sedimentological, taphonomical, and ichnological analyses of Late Jurassic sauropod tracks and associated structures, which were excavated on eight superimposed levels within a 0.65 m thick Late Jurassic biolaminite interval. This allows reconstructing the evolution of the tidal-flat palaeoenvironment throughout the biolaminite sequence. Time control is given by cyclostratigraphy: the sequence accumulated during a sea-level cycle in tune with an orbital precession cycle of 20 kyr. It can thus be determined where in the tidal-flat environment and when in the sea-level cycle the sauropods preferentially left their tracks, and under which circumstances these were incorporated into the sedimentary record. To conclude, detailed sedimentological and taphonomical analyses of vertebrate tracks improve palaeoenvironmental reconstructions, and this in turn facilitates the pertinent interpretation of the tracks in terms of ichnotaxonomy and palaeoecology.

Abstract: Generally, tidal-flats are ill-suited for the conservation of skeletal remains of terrestrial vertebrates, but they are important for the preservation of their footprints. Dinosaur footprints for example, are abundant in tidal-flat deposits throughout the Mesozoic. They fill gaps in the skeletal record and improve the knowledge of dinosaur locomotion and palaeoecology (e.g., Lockley 1998). The use of fossil footprints for ichnotaxonomy, for interpreting the palaeoecology of the trackmaker, or for reconstructing the palaeoenvironment is closely related to the understanding of footprint formation, taphonomy, and preservation processes. For this purpose, human footprints have been studied in a wide range of present-day tidal-flat environments, where microbial mats are ubiquitous (review in Gerdes & Krumbein 1994), and may lead to the formation of biolaminites (Gerdes et al. 1991). Microbial mats play an important role during the formation and preservation of vertebrate footprints (Marty et al. submitted). Due to different constellations in water content and nature of the microbial mat and underlying sediment, a wide range of true track morphologies was produced by the same human trackmaker. After formation, true tracks are in most cases subjected to modification due to physicochemical and biological taphonomic processes leading to modified true tracks. A (modified) true track may be consolidated by desiccation, lithification, or ongoing growth of the mat. The latter process may lead to the formation of overtracks. Amongst consolidated or (partially-) lithified footprints found on present-day tidal flats, poorly-defined true tracks, modified true tracks, and overtracks were most frequently encountered whilst unmodified and well-defined true tracks were rather rare (Marty et al., submitted). These observations made on human footprints of recent tidal-flat environments are compared with dinosaur footprints from Late Jurassic biolaminites, excavated on the Transjurane highway (Canton Jura, NW Switzerland; review of the tracksites in Marty et al. 2007), using surface documentations, cross-sectioned footprints, and sedimentological analyses of the encasing sediment. This comparison facilitates evaluating the relative abundance of true tracks, modified true tracks, undertracks, and overtracks, even if an unambiguous identification is not always possible. It is suggested that modified true tracks and overtracks make up an important part of fossil footprints and that they may be as common as undertracks. Even though only unmodified, well-defined true tracks should be used for ichnotaxonomy, poorly-defined true tracks, modified true tracks, and under- and overtracks are important for the reconstruction of the palaeoenvironment and of the physicochemical and biological sedimentary processes acting within.

Abstract: The Tchâfouè tracksite is located near Courtedoux (Ajoie, Canton Jura) on the future course of the federal highway A16 (Transjurane). From 2003 to 2007 the Paléontologie A16 systematically excavated 15 surfaces with true tracks of dinosaurs, finely superimposed within a 1 m thick biolaminite sequence. This sequence has been deposited during the early Late Kimmeridgian (Marty et al., 2003) under a (sub-)tropical climate on the Jura carbonate platform, located at the northern Tethys passive margin. As the site has been completely covered up by the highway and is no longer accessible, particular emphasis was put on the documentation of this tracksite. This includes detailed descriptions and measuring of footprints and trackways, casting, sedimentological analyses, and laser scanning and orthophotos of selected surfaces. In addition, several surfaces have been partly dismantled and on the whole a surface of approximately 300 m2 has been recovered. The main track level, which forms the base of the biolaminite sequence, was uncovered on a surface of 700 m2. The levels above were excavated on smaller areas only, because the biolaminite sequence was weathered towards the top. Over 2100 dinosaur footprints, 68 trackways of sauropods, and 96 trackways of bipedal and tridactyl � mainly theropod � dinosaurs are documented. The pes sizes range from 16 to 105 cm for sauropods, and from 9 to 57 cm for bipedal dinosaurs. Hereafter, we describe as tiny sauropods those with a pes length (PL)<25 cm, as small those with 25<PL<50 cm, as medium-sized those with 50<PL<75 cm, and as large those with PL>75 cm. Minute bipedal dinosaurs are characterized by PL<10 cm, small ones by 10<PL<20 cm, medium-sized ones by 20<PL<30 cm, and large ones by PL>30 cm. Independent of pes size, all studied quadrupedal sauropod trackways are pretty similar with respect to trackway configuration and patterns (for definition see Marty et al. 2006). All trackways show a pronounced heteropody (manus clearly smaller than pes), and even if the pes prints not always intersect the (hypothetical) trackway midline, they are essentially narrow-gauge. Accordingly, they may be assigned to the ichnotaxon Parabrontopodus (Lockley et al. 1994), commonly attributed to diplodocid sauropods (e.g., Day et al. 2002). The bipedal trackways show a pronounced variability concerning pes morphology. At least three morphotypes can be distinguished, which are believed to be independent of preservation and size. Some of the trackways of minute and small bipedal dinosaurs are similar to the ichnotaxon Carmelopodus, characterized by a lack of a fourth (proximal) pad impression on digit IV, and attributed to small theropods (Lockley et al. 1998). The majority of the trackways of medium-sized and large bipedal dinosaurs are similar to Megalosauripus, commonly attributed to megalosaurid theropods (Lockley et al. 1998). Finally, some of the large tridactyl footprints form a distinct new morphotype, which is characterized by footprints almost as wide as long, blunt toes, and a pronounced heel impression. This morphotype most probably testifies the presence of another large theropod with a fleshy foot, even if an attribution to an ornithischian dinosaur cannot be excluded. This may also be the case for some of the smaller tridactyl footprints, which could have been left by small ornithischian dinosaurs. The recurrent ichnocoenoses of the Tchâfouè tracksite show a great variability concerning taxonomical composition, size classes, trackway orientations, and trackway configuration and patterns. Most differ from each other even if a certain grouping can be recognized. They include associations of footprints of (1) tiny to medium-sized sauropods, small to medium-sized theropods, and large bipedal dinosaurs (main track level); (2) tiny to small sauropods and a large theropod (level 1015); (3) small sauropods and medium-sized to large theropods (level 1030); (4) small sauropods and tiny to small theropods (level 1055); (5) tiny to large sauropods and small to medium-sized theropods (level 1060); (6) small to medium-sized theropods and large bipedal dinosaurs (level 1065); (7) small to medium-sized theropods (level 1069). The wide range of these different ichnocoenoses - including the presence of very small and large animals - within a biolaminite sequence covering a time period of 20 to 40 ka (one or two elementary sequences correlated with the orbital precession cycle), provides evidence for a long-term presence of a well-developed dinosaur community on the Jura carbonate platform. Accordingly, they may be used to interpret the palaeoecology of the trackmakers (e.g., frequency, activities, gregariousness, species interactions).

Abstract: Microbial mats are benthic microbial communities, which are usually dominated by photosysnthetic prokaryotes, particularly cyanobacteria and photosynthetic bacteria (e.g., Bauld, 1984). They are ubiquitous on carbonate as well as on siliciclastic tidal flats (review in Gerdes & Krumbein, 1994). They may lithify by the precipitation of calcium carbonate (e.g., Chafetz & Buczynski, 1992), and consequently enhance the preservation potential of footprints and other traces. The products of benthic microbial communities are called �biolaminites� (the flat laminated type of stromatolites, Gerdes et al., 1991), and they frequently bear vertebrate footprints in the Recent as well as in the geologic record. Human footprints on microbial mats were studied and documented quantitatively in a wide range of present-day tidal flat environments of the Bahamas, Belize, Egypt, and Tunisia. These environments mainly differ from each other regarding sediment composition and texture, water content related to tidal range and climate, and the biological nature of the microbial mats. We address a number of issues concerning the formation and potential preservation of human footprints in present-day microbial mat covered tidal flat environments: (1) Relationships between the physical properties of the microbial mat (e.g., moisture content, mat thickness, elastic limit) and the environment and footprint morphology; (2) Consolidation and/or modification of the footprint morphology by continued growth of the microbial mat; (3) Footprint preservation and incorporation into the sedimentary record. These analyses in the Recent are relevant to better understand the formation and preservation of vertebrate footprints in fossil biolaminites, for the true track vs. undertrack discussion and consequently ichnotaxonomy, and for the interpretation of tidal-flat palaeoenvironments.

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Abstract: Since 2002 dinosaur tracks are systematically excavated in Late Jurassic (Kimmeridgian) carbonate platform sediments (Canton Jura, Switzerland). This platform formed part of the Northern Tethys passive margin in Late Jurassic times. To date, over 55 essentially narrow-gauge trackways of sauropods, and over 90 trackways of bipedal, tridactyl dinosaurs chiefly attributed to theropods, have been excavated and documented on multiple (>15) track-bearing surfaces. This provides insight into track formation and taphonomy, in particular the distinction of true tracks from under- and overtracks, a key point for consistent ichnotaxonomy and paleoecological interpretations. Multiple ichnocoenoses (associations of true tracks on a single surface) include (1) trackways of tiny (FL (footprint length)<25 cm) and large (FL>100 cm) sauropods with trackways of small (10<FL<25 cm) theropods; (2) trackways of tiny and medium-sized (25<FL<40 cm) sauropods with trackways of minute (FL<10 cm), small and medium-sized (25<FL<30 cm) theropods; (3) trackways of tiny and medium-sized sauropods with trackways of medium-sized and large (FL up to 50 cm) theropods. These ichnocoenoses exhibit diverse trackway orientation patterns and trackways with changes in gauge and gait of both sauropods and theropods. Even if these ichnocoenoses only partially reflect the former terrestrial vertebrate ecosystem of the platform, they indicate a recurrent presence of diverse dinosaur communities, at least during periods with prolonged inter- to supratidal conditions. The repeated associations of trackways of similar patterns and track morphology of very small and medium or large sauropods give a hint for different age classes within a single species. Moreover, this suggests that�contrary to recent publications�stance and resulting trackway gauge of sauropods is not necessarily related to ontogeny. This might be corroborated by more ichnocoenoses obtained by ongoing excavations. Finally, the paleogeographic situation implies that the platform was frequently connected to continental landmasses. This probably prevented a development of insular, dwarfed faunas, as has been postulated for similar carbonate platform settings.

Abstract: Since 2002 dinosaur tracks are systematically excavated in Late Jurassic (Kimmeridgian) carbonate platform sediments (Canton Jura, Switzerland). This platform formed part of the Northern Tethys passive margin in Late Jurassic times. To date, over 55 essentially narrow-gauge trackways of sauropods, and over 90 trackways of bipedal, tridactyl dinosaurs chiefly attributed to theropods, have been excavated and documented on multiple (>15) track-bearing surfaces. This provides insight into track formation and taphonomy, in particular the distinction of true tracks from under- and overtracks, a key point for consistent ichnotaxonomy and paleoecological interpretations. Multiple ichnocoenoses (associations of true tracks on a single surface) include (1) trackways of tiny (FL (footprint length)<25 cm) and large (FL>100 cm) sauropods with trackways of small (10<FL<25 cm) theropods; (2) trackways of tiny and medium-sized (25<FL<40 cm) sauropods with trackways of minute (FL<10 cm), small and medium-sized (25<FL<30 cm) theropods; (3) trackways of tiny and medium-sized sauropods with trackways of medium-sized and large (FL up to 50 cm) theropods. These ichnocoenoses exhibit diverse trackway orientation patterns and trackways with changes in gauge and gait of both sauropods and theropods. Even if these ichnocoenoses only partially reflect the former terrestrial vertebrate ecosystem of the platform, they indicate a recurrent presence of diverse dinosaur communities, at least during periods with prolonged inter- to supratidal conditions. The repeated associations of trackways of similar patterns and track morphology of very small and medium or large sauropods give a hint for different age classes within a single species. Moreover, this suggests that�contrary to recent publications�stance and resulting trackway gauge of sauropods is not necessarily related to ontogeny. This might be corroborated by more ichnocoenoses obtained by ongoing excavations. Finally, the paleogeographic situation implies that the platform was frequently connected to continental landmasses. This probably prevented a development of insular, dwarfed faunas, as has been postulated for similar carbonate platform settings.

Abstract: In 2003, the �Palaeontology A16� discovered first dinosaur tracks at Chevenez�Combe Ronde near Porrentruy in the Swiss Jura. The tracks are located in intertidal calcareous laminites, deposited on a shallow carbonate platform during the early Late Kimmeridgian (Marty et al., 2003). Tracks have been excavated in three areas (total of about 570 m2). They occur on the main track level as well as on six bedding planes within the overlying laminites. The main track level yields one of the richest Jurassic ichnocoenosis with over 50 trackways of small sauropods and particularly small theropods. The laminites display tracks and trackways of sauropods, which show a wide range of preservation state. The systematic track excavation offered the possibility to uncover track-bearing horizons layer by layer, and thus to document and study hundreds of dinosaur tracks unaffected by differential weathering (Fig. 1). Several sauropod tracks have been extracted in blocks as heavy as one ton. The blocks were then consolidated with epoxy and cut with an industrial stone saw. The cross sections will facilitate the study of sedimentology and taphonomy of the dinosaur tracks. This will permit to establish criteria to distinguish true tracks from over- and undertracks.

Abstract: Since 2002 the �Palaeontology A16� systematically excavates dinosaur tracks in early Late Kimmeridgian platy limestones (Plattenkalke) along the �Transjurane� highway. The tabular and thinly-bedded platy limestones have a stromatolitic appearance in the field, however it is difficult to recognize in polished sections or thin sections. Bedding planes yield a diverse tetrapod ichnocoenose exhibiting different size-classes of both sauropod and theropod dinosaur tracks. They also display desiccation cracks and wave- and current ripples. The layer-by-layer excavation clearly identifies overtracks, true tracks (elite tracks) and undertracks, whereas dinoturbated layers generally consist of true tracks as well as over- and undertracks stemming from adjacent levels. Several sauropod tracks have been artificially consolidated and cut into serial sections. Together with the sedimentological and ichnological data gained from bedding planes, the cross sections allow conclusions about the genesis and the taphonomical history of a given dinosaur track and the substrate consistency at the time of the track formation respectively. Sedimentological and ichnological analysis of the platy limestones combined with track taphonomy and palaeoecological information allow a subdivision into several different units. These units correspond to different palaeoenvironments ranging from shallow lagoon to beach and to supratidal flat (algal marsh). In similar recent environments of the Bahamas and the Sabkha El Melah (Tunisia), a wide range of track morphologies has been observed, which stems basically from differences in water content of the sediment, the presence of microbial-algal mats that bind and stabilize the sediment, and early-diagenetic carbonate cementation, even if exceptional behaviour of the trackmaker is present or weathering affects the track morphology. To conclude, the understanding of track taphonomy helps to characterize the palaeoenvironment and is indispensable for ichnotaxonomical classification.

Abstract: The palustrine Facies Rognacien can be found in the northern French Pyrenean foreland (Southern France). So far it has not been known, in what environment exactly it was deposited, and whether the K/T-boundary lies within the Facies Rognacien or the overlying Facies Vitrolien, which is almost entirely built up of rock-forming Microcodium. The study of the Charophytes facilitated to locate the K/T-boundary in the lower part of the upper limestone sequence of the Facies Rognacien. The sedimentological (microfacies analysis) and paleoecological studies revealed, that inside the study area most carbonates of the Facies Rognacien can be attributed to the freshwater marsh facies sensu Platt and Wright (1992), which was formed in ancient seasonal wetlands. In this environment small lakes or ponds, the marginal lake facies sensu Freytet & Plaziat (1982) respectively, account only for a small part of the depositional area. The Facies Rognacien is thus a good example for an ancient wetland, even if Peybèrnes & Combes (1999) state, that the sediments of the Facies Rognacien become increasingly lacustrine in the north of the study area.

Abstract: Since 2000, a Swiss paleontological team (the �Section de paléontologie�) carries out systematic excavations along the future course of the �Transjurane� highway (Jura, northwestern Switzerland). Numerous fossiliferous beds are excavated and studied at several localities, all in the vicinity of the town of Porrentruy. These beds are precisely dated by ammonites to the Kimmeridgian. They correspond to coastal deposits of a shallow carbonate platform, at the threshold between the boreal and the tethyan realms. So far, the excavations have yielded a rich and diverse fauna of invertebrates and vertebrates (fish and reptiles with notably lots of dinosaur tracks). We report here the palaeontological evidence for emersions of the carbonate platform in northwestern Switzerland during the Kimmeridgian, an area assumed to be marine. The emersions are indicated by the occurrence of dinosaur tracks, that is first hand evidence of biological activity of terrestrial organisms in situ. The dinosaur ichnites (assigned to theropods and sauropods) are abundant, diverse, and occur on at least twelve beds during three sequences of emersion. This shows that dinosaurs could habitually enter in this coastal marine environment and that the emerged land could provide suitable terrestrial habitats for dinosaur populations. This unexpected terrestrial paleoenvironment, which needs to be characterized, is important for palaeogeographic reconstructions of western Europe during the Kimmeridgian.

Abstract: Since 2000, a Swiss paleontological team (the �Section de paléontologie�) carries out systematic excavations along the future course of the �Transjurane� highway (Jura, northwestern Switzerland). Numerous fossiliferous beds are excavated and studied at several localities, all in the vicinity of the town of Porrentruy. These beds are precisely dated by ammonites to the early Late Kimmeridgian. They correspond to coastal deposits of a shallow carbonate platform, at the threshold between the boreal and the tethyan realms. So far, the excavations have yielded a rich and diverse fauna of invertebrates and vertebrates (fish and reptiles), notably lots of dinosaur ichnites. We report here the first synthetic overview of the Transjurane reptilian fauna and a comparison with other Late Jurassic Lagerstätten of Western Europe, which have been deposited in similar paleoenvironments (Canjuers, Cerin, Crayssac, Solnhofen, Solothurn). The reptilian fauna includes skeletal remains of chelonians (Plesiochelyidae, �Thalassemydidae�), crocodilians (Teleosauridae, Metriorhynchidae) and of a pterosaur. Moreover, the presence of sauropod and theropod dinosaurs is attested by tracks. The composition of the reptilian fauna is consistent with that of the other sites, but three major groups are still missing (lepidosaurs, ichthyopterygians, sauropterygians). The sauropod ichnites are abundant and occur on several levels, with a large range of footprint size and trackway pattern. This supports the hypothesis that some of these large-bodied terrestrial herbivores could habitually enter in coastal marine environments.

Abstract: Since 2000, the �Section de paléontologie� carries out palaeontological excavations along the future �Transjurane� highway. So far, this has led to the discovery of four dinosaur tracksites in the vicinity of Porrentruy, which are all located in intertidal calcareous laminites, deposited in a shallow carbonate platform setting of early Late Kimmeridgian age. The first tracks were discovered in February 2002 at Courtedoux-�Sur Combe Ronde�. The main track level has been excavated and documented on a surface of 650 m2 and reveals 17 sauropod trackways of the ichnogenus Parabrontopodus and 2 theropod trackways (Marty et al. 2003). On an overlying level, the trackway of a �baby� sauropod (pes length 20 cm) was discovered (Marty & Cavin 2003). The laminites contain at least 6 track-bearing horizons, which can still be excavated on about 900 m2. The whole site will probably be protected in situ underneath a highway bridge specifically built for this purpose. In 2003, tracks were discovered at Chevenez-�Combe Ronde� and Courtedoux-�Bois de Sylleux�, and finally in 2004 at Courtedoux-�Tchâfouè� during archaeological and palaeontological prospecting. To date, the Courtedoux-�Bois de Sylleux� and Courtedoux-�Tchâfouè� sites have just been prepared for excavation. At �Bois de Sylleux�, more than 2000 m2 are available for excavation, and so far, about 50 tracks of sauropods (ranging from 0,2 to 1,1 m in pes length) and several tracks of theropods have been found on 4 different levels. At �Tchâfouè� around 1000 m2 have been prepared for excavation and so far tracks of medium-sized sauropods and theropods have been observed. The Chevenez-�Combe Ronde� site is excavated since autumn 2003 on three excavation areas. Tracks have been uncovered on 5 different levels, whereas the main track level at the base of the laminites yields one of the richest Jurassic ichnocoenosis known so far. On this level, 6 Parabrontopodus and 3 Brontopodus trackways of small (pes length 25-35 cm), probably juvenile sauropods, as well as over 20 trackways of very small-sized (pes length of 8 cm) to medium-sized (pes length of 10-20 cm) theropods (Figs. 1 & 2) have been documented so far. As the excavation sector 3, where most of the small theropod tracks are located will be partially destroyed by the construction of the highway, a laserscan of the whole surface is made. Moreover, important parts are moulded with silicon and important tracks, which cannot be protected in situ, will be extracted with an industrial stone saw. In conclusion, four tracksites with at least 12 track-bearing horizons at 3 stratigraphically different positions have been discovered so far. The systematic track excavations offer the possibility to uncover track-bearing horizons layer by layer, and thus to study tracks unaffected by differential weathering. The study of over- and undertracks, as well as of track cross sections will provide important insights into the formation (sedimentology) and preservation (taphonomy) of dinosaur tracks. Moreover, on all four sites fossiliferous marine marls and limestones are excavated as well, yielding a rich marine vertebrate and invertebrate fauna, including ammonites.

Abstract: The importance of safeguarding paleontological heritage has been recognized in the Canton Jura (northwestern Switzerland) and as a result of the construction of the highway �Transjurane�, the �Section de paléontologie� was established in February 2000. This new institution is charged with safeguarding and examining the paleontological heritage along the course of the future highway. So far, three dinosaur tracksites, which together have revealed 12 track-bearing horizons, were located in laminites of Kimmeridgian age. First tracks were discovered in 2002 at the �Courtedoux-Sur Combe Ronde� site, meanwhile one of the most important sites for Jurassic sauropod tracks. The site can be protected in situ over a surface of about 1500 square meters underneath a highway-bridge specifically built for this purpose. In 2003, tracks were discovered at the �Chevenez-Combe Ronde� and �Courtedoux-Bois de Sylleux� sites, where excavations are still carried out. Both sites can at least be protected in the security zones beside the future highway. The recent discoveries of dinosaur tracksites of international importance have led to the idea of a Jura Geopark, allowing for integration of other existing geosites, as well as archeological and natural sites. So far, a commission charged to evaluate the future possibilities and economic potential of such a park has been founded. The poster outlines the dinosaur tracksites along the �Transjurane� highway and the latest developments concerning a future Jura Geopark.

Abstract: The importance of safeguarding paleontological heritage has been recognized in the Canton Jura (northwestern Switzerland) and as a result of the construction of the highway �Transjurane�, the �Section de paléontologie� was established in February 2000. This new institution is charged with safeguarding and examining the paleontological heritage along the course of the future highway. This has led to the discovery of three dinosaur tracksites so far. All of them were located in intertidal calcareous laminites of early Late Kimmeridgian age, which were deposited in a shallow carbonate platform setting. The first tracks were discovered in February 2002 at the �Courtedoux-Sur Combe Ronde� site. The main track level has been excavated and documented on a surface over 650 m2 and reveals 17 sauropod (ichnogenus Parabrontopodus) and 2 theropod trackways. On an overlying level, the trackway (pes length 20 cm) of a �baby� sauropod was discovered. The laminites contain at least 6 track-bearing horizons, which remain to be excavated over about 950 m2. The site will probably be protected in situ underneath a highway-bridge specifically built for this purpose. In 2003, tracks were discovered at the �Chevenez-Combe Ronde� and �Courtedoux-Bois de Sylleux� sites during archeological and paleontological prospecting. The former site was discovered in August and its excavation began in autumn. It yields several trackways (pes length 25-30 cm) of the ichnogenus Parabrontopodus, which can be attributed to juvenile or particularly small diplodocid sauropods. Moreover, two morphologically different sets of particularly small tridactyl tracks (pes length 5-15 cm) of probably theropod origin were recognized. The �Courtedoux-Bois de Sylleux� site, containing tracks of juvenile (pes length 20-25 cm) and adult (pes length up to 1 m) sauropods, was discovered in the autumn of 2003. The main excavation started in summer 2004. Together, the three sites have revealed 12 track-bearing horizons to date. The excavations offer the possibilty of uncovering track-bearing horizons layer-by-layer, and thus of studying tracks unaffected by differential weathering. The study of over- and undertracks, as well as track cross sections provides important insights into the formation (sedimentology) and preservation (taphonomy) of dinosaur tracks. In 2004, dinosaur track excavations are carried out at at the �Chevenez-Combe Ronde� and �Courtedoux-Bois de Sylleux� sites, where besides the track excavations, fossiliferous marine marls and limestones are also investigated. The present conference will outline the dinosaur track excavations along the �Transjurane� highway and present the latest results.

Abstract: As a result of the construction of the �Transjurane� highway, a new paleontological project, the �Section de paléontologie� was established in February 2000, engaged to save and examine the paleontological heritage of the future highway course in the Jura Canton, Northern Switzerland (Marty et al., 2003b). In 2002 a new dinosaur tracksite was discovered in Courtedoux (about 5 km to the west of Porrentruy) on the future course of the �Transjurane� highway. At the Courtedoux site, bedding is sub-horizontal and paleontological excavations are carried out in a cross-section of a total thickness of about 10 metres, which is located between the Banné Member (Gygi, 2000) and the Marnes à virgula, forming the top of the section. The section can be dated by means of aspidoceratid ammonites to the Mutabilis-zone of the Reuchenette formation (Upper Kimmeridgian). The section starts with intertidal (wave- & current-ripple marks) to supratidal (desiccation cracks) track-bearing calcareous laminites of a total thickness of about 1 metre. Even though the confined tidal environment suggests a low ichnodiversity, the laminites of the Courtedoux section exhibit an ichnofabric network at all scales of dinosaur tracks and invertebrate traces. Dinosaur tracks have been reported from six levels. So far the lowermost level has been excavated on a surface of about 600 m2, revealing more than 650 sauropod and theropod tracks, of which about 400 can be resolved into 17 sauropod trackways of the ichnogenus Parabrontopodus (Lockley et al., 1994) and 2 trackways of theropod dinosaurs as yet not attributed to any ichnogenus. The sauropod trackway pattern reveals evidence for local shoreline-controlled travel by several groups of sauropods. The order of passing of the different groups can be determined by analyzing the overlapping relationships at �crossroads� (Marty et al., 2003a). Beside the dinosaur tracks, different kind of invertebrate trace fossils (a.o. horizontal, Y- to T-shaped, branching Thalassinoides) are found on several levels, sometimes together with dinosaur tracks. Interactions between dinosaur tracks and invertebrate traces will still be studied in detail, but the original formation depths of the invertebrate traces, which might have been quite deep in order to escape the instability of the ever-shifting substrate surface (Frey & Pemberton, 1984), might remain unknown. As the shoreline is especially in tidal environments difficult to define (Goldring, 1993), an attribution to the Scoyenia (dinosaur tracks), Skolithos or Cruziana (Thalassinoides) ichnofacies respectively might not be very appropriate. Goldring (1993) states, that brackish water trace fossils are commonly linked together as a mixture of structures typical of both the Skolithos and Cruziana ichnofacies. Above the laminites, limestones, calcareous marls and several hardgrounds follow, being for the major part strongly bioturbated. Determinable traces are especially found in calcareous marls (Thalassinoides and cf. Ophiomorpha) and hardgrounds (vertical, slightly curved borings of the cf. Trypanites ichnofacies). Within the excavation section, low to high diversification of the marine fauna (turtles, crocodiles, fish, echinoderms, cephalopods, molluscs, serpulids...) indicate a very dynamic evolution of the shallow, mixed carbonate-siliciclastic platform environment. Detailed analysis of bathymetry, salinity, confinement, eutrophication, water oxygenation and turbidity might become part of future research. Thus the �Section de paléontologie� highly appreciates ichnological suggestions, discussions and collaborations.

Abstract: The importance of safeguarding the palaeontological heritage has been recognized in the Canton Jura, and as a result of the construction of the �Transjurane� highway, a new project, the �Section de paléontologie� was established in February 2000. The project was initiated and is supported by Professor J.-P. Berger from the Departement of Geosciences, University of Fribourg and PD Dr. C. A. Meyer, Director of the Natural History Museum Basel. The �Section de paléontologie� is engaged to save and examine the palaeontological heritage on the future highway course in the Canton Jura, Northwestern Switzerland. The project is financed for 95% by the Swiss Federal Roads Authority (FEDRO), and for 5% by the Canton Jura. Similar archeological survey projects are common since quite a long time, but this is the first time that palaeontological heritage finds a similar acceptance in Switzerland, if not even Europe (Marty et al., submitted b). The �Section de paléontologie� first accomplishs palaeontological and sedimentological prospection, as well as geological mapping along the future highway course to determine the approximate position of the most fossiliferous beds. Afterwards these beds are localised by palaeontological prospecting using a shovel excavator. If significant findings are made, a palaeontological excavation can be envisaged. These excavations are carried out before the conctruction of the highway starts. However, important sites are sometimes not discovered until the construction of the highway. In this case a suitable solution for an emergency excavation has to be worked out with the highway engineers in charge. This happened for example in the case of the Oligocene �La Beuchille� site, which is further described below. Palaeofauna and palaeoflora of the Early Oligocene �La Beuchille� site In autumn, 2001, the Tertiary research team concentrated its efforts on the discoveries made at the �La Beuchille� site, located about 1 km south of Delémont, Canton Jura. This site is an excellent example of the �Molasse alsacienne supérieure� (USM; Lower Freshwater Molasse) (Picot, 2002). Iberomeryx minor dates the deposits of the site to the biostratigraphic mammal zone MP23, which corresponds to the Early Oligocene (Becker et al., submitted). After a preliminary field investigation, which included the palaeontological and sedimentological study of more than twenty sections, a palaeobotanic- and vertebrate-bearing outcrop was excavated during 6 weeks. This excavation unearthed a large quantity of well-preserved remains of fossil trees, but also vertebrate bones and teeth. All lithofacies and architectural elements of the �La Beuchille� site represent distal siliciclastic deposits with weakly defined channel forms of a flood plain or crevasse splay, which the latter can achieve until 10 km of length and up to 10 km wide during an important flooding event. The presence of small channels of fall is also often observed (Becker, 2003). The fossil remains of the palaeoflora and palaeofauna are mostly fragmentary and never in connection (disarticulated mammal remains). Certain bones show marks of abrasion or even polished surfaces. The deposit of the �La Beuchille� site is thus a typical taphocoenosis of a fluvial environment, where fossil remains are transported and sorted. The animal community shows affinities to an aquatic and forested environment. Anthracotherium sp. (the hippo-like �coal beast�) and aquatic gastropods (Planorbis, Lymnaea) indicate an at least partially swampy environment. Soft-shell turtles clearly indicate the presence of rivers or swampy areas, as well as a relatively high palaeotemperature (rarely below 150C) with only a weak annual variation. Terrestrial gastropods (Helicidae) and Iberomeryx minor, a small primitive hornless ruminant, reflect both the partially forested character of the environment. Another interesting aspect is the tree remains. The presence of alder (Alnus) and walnut trees (Juglandacae) suggest a bi-seasonal climate. The coexistence of Pinacae and Taxodiacae suggests a high temperature with few annual variations, a possible relief and an elevated humidity, which is also supported by the presence of ferns. Numerous floodings represented in the lithofacies suggest a certain degree of saisonality for the humidity, but which might never have led to the complete desiccation of the flood plain. In the Early Oligocene, the area of Delémont was a vast and relatively flat swampy forest zone, subjected to regular floodings, fed by several alluvial systems derived from the North and the West, which have silted up the palaeoenvironment. The floodings sometimes had devastating consequences, as might be documented in the deposits of the �La Beuchille� site. The stratigraphic and geographic position of the "La Beuchille" site is a key element for understanding the modalities of the southern coastline of the Rhine graben sea. The Courtedoux dinosaur tracksite During archaeological and palaeontological prospection on the future course of the �Transjurane� highway, a new dinosaur tracksite was discovered in Courtedoux (about 5 km to the west of Porrentruy) in February 2002. Intertital to supratidal calcareous laminites contain at least 6 track-bearing levels and one layer with vertebrate remains in a total thickness of about 1 m. During the main 2002 excavation phase, the main track level was uncovered over the whole width of the future highway on a surface of about 650 m2, revealing more than 650 dinosaur footprints. The tracks are in general well preserved as imprints (epichnia or negative epirelief) and exhibit most well definded sediment displacement rims. About 400 can be resolved into trackways of 2 theropod and 17 sauropod dinosaurs. The latter belong to the ichnogenus Parabrontopodus (Lockley et al., 1994) being the first clear evidence in central Europe and the youngest well-dated evidence for this ichnogenus worldwide. Parabrontopodus trackways indicates sauropods like the diplodocids with large hind limbs, long tail and a small neck and head. A bimodal pattern of the sauropod trackways, each with approximate parallel trackway orientation, might suggest local shoreline-controlled travel and/or gregarious behaviour of several groups of sauropods. The size range for the sauropod pes prints is very small, and lies between 34.4 and 46.8 cm length and between 27.0 and 35.7 width (Marty et al., submitted a). However, on an overlying level, about 2 m of a narrow gauge sauropod trackway segment has been excavated, exhibiting evidence for even smaller sauropods. The mean pes print length is about 20 cm and the mean width about 13.5 cm. The gleno-acetabular distance is about 0.8 m and according to the formula of Thulborn (1990: 252) a hip height of about 1.2 m results (hip height = 5.9 x pes length) (Marty & Cavin, 2003). Such small sauropod tracks are only known from the Cretaceous Jindong Formation of South Korea (Lim et al., 1994) and Lockley (1994) attributes them to very young (post-hatchling) individuals in their first year of growth. The Courtedoux tracksite thus reveals the first ichnological evidence for Jurassic �baby�-sauropods (Marty & Cavin, 2003). The main track level has been documented by means of a classical manual graphic documentation, followed by digitization, but also a new laser-scanning system (Cyrax), allowing the 3D modelling of the whole surface (Leica Geosystems, 2003), has been applied for the first time in the field of palaeontology. Beside the excavation of dinosaur track-bearing laminites, the �Section de paléontologie� also excavates overlying marine limestones and marls. The excavation section has a total thickness of about 10 metres, and it is located between the Banné Member (Gygi, 2000) and the Marnes à virgula, forming the top of the section. Invertebrates and remains of turtles, crocodiles, sharks and bony fishes are dug out. Aspidoceratid ammonites, found about 4 meters above the track-bearing laminites, date the excavations to the Mutabilis-zone (sensu �Biome Franco-Germanique�) of the Reuchenette Formation (Upper Kimmeridgian). The Courtedoux tracksite may thus correspond to the �Middle Kimmeridgian Megatracksite� sensu Meyer (2000) (Marty et al., submitted a). The Courtedoux �Sur Combe Ronde� tracksite is a �multithematical� geotope (Jordan, 2002) or geosite of international importance and it has an extraordinary scientific potential. Since its discovery, the protection and the conservation of the site in place, is promoted by the �Section de paléontologie�. According to the actual Swiss law, the site is a natural object. It has to be protected from destruction in place, as in Switzerland, heritage sites of national value range on the same level of significance as federal infrastructure projects like highways. Thus and thanks to the excellent collaboration of the highway-authorities at different levels, the Courtedoux tracksite will definetly be protected over an area of approximately 1500 m2 underneath an especially constructed highway bridge (Marty & Hug, 2003). The laminites can still be excavated and documented layer by layer on about 900 m2 and the site has thus the potential for development into one of world�s largest and most important sauropod tracksites (Lockley, 2002). The bridge further provides ideal conditions for the protection, conservation, scientific research, and public viewing of the site, but also for the installation of an educational, tourist and interpretative center (Marty et al., submitted b). The site could even figure as a main attraction of a future Jura Geopark (Berger, 2003), which, integrated into a regional green or eco tourism concept, may create and safeguard jobs and provide sustainable economic development in the rural Jura environment (Marty & Hug, 2003).

Abstract: The importance of safeguarding the palaeontological heritage has been recognized in the Canton Jura, and as a result of the construction of the �Transjurane� highway, the �Section de paléontologie� was established in February 2000. The project is engaged to save and examine the palaeontological heritage on the future highway course in the Canton Jura. It is financed by the Swiss Federal Roads Authority (FEDRO: 95%), and by the Canton Jura (5%) (Marty et al., accepeted b). The �Section de paléontologie� accomplishs palaeontological and sedimentological prospection, as well as geological mapping along the future highway course, to determine the approximate position of fossiliferous beds. Afterwards these beds are localised by palaeontological prospecting using a shovel excavator. If significant findings are made, an excavation can be envisaged. These excavations are carried out before the construction of the highway starts. However, important sites are sometimes not discovered until the construction of the highway. In this case a suitable solution for an emergency- excavation has to be worked out with the highway-engineers in charge. At the Courtedoux-�Sur Combe Ronde� Dinosaur tracksite, trackways of 2 theropod and 17 sauropod dinosaurs on the main track level (Marty et al., accepted a), and a �baby�-sauropod trackway (Marty & Cavin, 2003) on an overlying level, have been excavated in calcareous laminites in 2002. According to the actual Swiss law, the Courtedoux tracksite is a natural object (geotope) with an extraordinary scientific value, and the site will definetly be protected over an area of approximately 1500 m2 underneath an especially constructed highway bridge. This bridge will provide ideal conditions for future excavation, protection, conservation, scientific research, and public viewing of the site, but also for the installation of an educational, tourist and interpretative center (Marty et al., accepted b, Marty & Hug, 2003). During 2003, new track-bearing horizons were found at Courtedoux �Sur Combe Ronde�, as well as at Chevenez �Combe Ronde�. Further, excavations were carried out in Upper Kimmeridgian marine limestones and marls at Courtedoux �Tchâfouè� and �Vâ-tche-Châ�.

Abstract: Das Dinosaurier-Spurenvorkommen von Courtedoux (JU) ist eines der weltweit bedeutensten seiner Art der späten Jurazeit (Lockley, Meyer, 2002). Es wurde im Februar 2002 auf dem zukünftigen Trassee der Autobahn A16 (Transjurane) entdeckt und ab April von der �Section de paléontologie� ausgegraben. Die �Section de paléontologie� ist ein Pilotprojekt in der Schweiz, wenn nicht sogar in Europa. Sie untersucht und birgt das paläontologische Kulturgut auf der zukünftigen Linienführung der Transjurane (N16) im Kanton Jura. Das Projekt ist in das kantonale Amt für Denkmalpflege und Kultur (OPH) integriert und zu 95% durch das Bundesamt für Strassen (ASTRA) und zu 5% durch den Kanton Jura finanziert. An der Fundstelle finden sich Fussspuren von Dinosauriern auf mindestens 6 Schichtoberflächen innerhalb von circa 1 m mächtiger Laminite am �bergang vom Frühen ins Späte Kimmeridge. Diese Laminite befinden sich an der Basis einer circa 10 m mächtigen ausgesprochen fossilreichen Kalk-Mergel Wechsellagerung, in der von der Section de paléontologie Flächengrabungen durchgeführt werden. Das Spurenvorkommen ist deshalb sehr gut in ein paläoökologisches Gesamtbild integriert und kann durch Ammoniten genau datiert werden (Marty et al, 2002a & 2002b). Im Jahre 2002 wurde der unterste Horizont des Spurenvorkommens auf einer Fläche von rund 600 m2 freigelegt. Darauf sind über 650 einzelne Trittsiegel von Dinosauriern sichtbar, von denen sich rund 400 in 17 Fährten von quadrupeden, herbivoren Sauropoden und 2 Fährten von bipeden, karnivoren Theropoden gruppieren lassen. Die schmalen Fährten der Sauropoden gehören zum Ichnogenus Parabrontopodus (Lockley et al., 1994) welches in Courtedoux zum ersten Mal in der Schweiz nachgewiesen wurde und diplodociden Sauropoden zugerechnet wird. Die Fährtenplatte von Courtedoux liegt nahezu horizontal und ist direkt zugänglich. Die anderen bekannten, grossen Spurenvorkommen der Schweiz Vieux Emosson (Demathieu et al., 1982), Lommiswil (Meyer, 1990 & 1993), Moutier (Meyer, 1997) und Beckenried (Meyer et al., 2001) hingegen, sind nur mit klettertechnischen Mitteln zugänglich. Im Jahre 2002 konnten deshalb über 10'000 Besucher von einem extra eingerichteten didaktischen Rundgang profitieren und manifestierten so zusammen mit dem grossen Echo von Seiten der Wissenschaft und seitens der Medien (Printmedien, Radio und Fernsehen) das grosse Interesse eines sehr breit gefächerten Publikums. Für die wissenschaftliche Bearbeitung konnten mehrere Forscher unterschiedlichster Fachbereiche der Geowissenschaften (Ichnologie, Sedimentologie, Stratigraphie, Tektonik, usw.) gewonnen werden. Um die wissenschaftliche Bedeutung der Fundstelle zu evaluieren und gleichzeitig zu untermauern, hat die Section de paléontologie zudem Expertenrapporte (Meyer, Lockley, Jordan, 2002) in Auftrag gegeben. Diese belegen klar, dass das Spurenvorkommen von Courtedoux eines der weltweit bedeutensten dieser Art der späten Jurazeit ist (Lockley, Meyer, 2002), ein multithematisches Geotop (Naturdenkmal im Sinne des NHG und ZGB) mit hohem didaktischen Wert und grossem touristischen Potential darstellt und entsprechend der schweizerischen Gesetzgebung (Art. 702 ZGB, Art. 37 RPG & Art. 15f NHG) an Ort und Stelle geschützt werden muss (Jordan, 2002). Die Section de paléontologie führt seit der Entdeckung der Fundstelle eine intensive Kommunikation und Zusammenarbeit mit einer Vielzahl von Ansprechpartnern. In politischer Hinsicht mit dem Bundesamt für Strassen (ASTRA), Ministerinnen und Ministern des Kantons Jura, Vertretern des Kantonsparlament, dem kantonalen Amt für Brücken und Strassen (Jura, PCH), dem kantonalen Amt für Wasser und Naturschutz (Jura, OEPN), Gemeindevertretern, dem kantonalen Chef der A16 (Transjurane), mit Ingenieuren und mit Museen. Die wichtigsten Voraussetzungen für einen dauerhaften Schutz der Fundstelle in situ konnten so bereits geschaffen werden. Auf den neuesten Autobahnplänen erscheint über der Fundstelle eine extra konstruierte Autobahnbrücke. Diese schützt die Fundstelle direkt gegen die witterungsbedingte Erosion, die grösste Gefahr für ein einmal freigelegtes Spurenvorkommen. Nachdem der Schutz der Fundstelle sichergestellt ist, muss ihr Wert auf Bundes- und Kantonsebene eingeschätzt und ein angebrachtes Besucher-Konzept entwickelt werden. Das Fährtenvorkommen hat sein hohes didaktisches und touristisches Potential auf jeden Fall bewiesen und könnte in Zukunft durchaus als Tourismusmagnet für ein regionales Geopark-Konzept verwendet werden, das wiederum wichtige wirtschaftliche Impulse auslösen kann (Jordan, 2002). �hnlich bedeutende Fundstellen (Münchehagen/De, Barkhausen/De, Alameda Parkway-Dinosaur Ridge/USA, usw.) werden weltweit vermehrt für die Einrichtung von Besucherzentren (Lockley, 1993, Lockley, 1995, Lockley & Meyer, 2000) oder sogar für den Aufbau von Geoparks (z.B. Münchehagen, D, Dinopolis, E) genutzt. Bereits laufen Bestrebungen, die Interessensgemeinschaften in einer Kommission an einen Tisch zu bringen und die Machbarkeit eines Besucherzentrums (z.B. ein Museum als zentraler Ort eines Geo- oder Naturparkes) ist ein Haupthema der Frühlingslegislatur 2003 des kantonalen Erziehungsdepartementes. Die Section de paléontologie unternimmt alles, um eine bestmögliche Präsentation der Fundstelle innerhalb eines regionalen Geopark-Konzeptes zu erreichen und ist deshalb an einem Erfahrungsaustausch mit ähnlichen Projekten sehr interessiert.

Abstract: In 2002, the �Section de paléontologie� discovered and excavated a new dinosaur tracksite at Courtedoux on the future course of the �Transjurane� highway. Intertidal to supratidal calcareous laminites of the Reuchenette Formation (Upper Kimmeridgian) contain at least 6 track-bearing levels in a total thickness of nearly 1 m. In 2002, the main track level has been excavated on a surface of about 650 m2, revealing 2 trackways of theropods and 17 trackways of sauropods (Marty et al., submitted b). The latter belong to the ichnogenus Parabrontopodus (Lockley et al., 1994) being the first clear evidence in central Europe and the youngest well-dated evidence for this ichnogenus worldwide. The size range for the sauropod pes prints is between 34.4 and 46.8 cm length and between 27.0 and 35.7 width, which are the smallest known sauropod tracks in the Jurassic so far (Marty et al., submitted a). However, on an overlying level, about 2 m of a narrow gauge (interpedes distance/internal trackway width being about 13 cm) sauropod trackway segment has been excavated, exhibiting evidence for even smaller sauropods. The mean pes print length is about 20 cm and the mean width about 13.5 cm. The gleno-acetabular distance is about 0.8 m and according to the formula of Thulborn (1990: 252) a hip height of about 1.2 m results (hip height = 5.9 pes length). Such small sauropod tracks are only known from the Cretaceous Jindong Formation of South Korea (Lim et al., 1994) and Lockley (1994) attributes them to very young (post-hatchling) individuals in their first year of growth. The Courtedoux tracksite thus reveals the first ichnological evidence for Jurassic �baby�-sauropods. The Courtedoux �Sur Combe Ronde� tracksite is a geotope or geosite of international importance and it will be protected over an area of approximately 1500 m2 underneath an especially constructed highway-bridge. The site has the potential for development into one of the most important sauropod tracksites and it offers plenty of possibilities for future excavations and research, but also for public viewing and installation of an educational, tourist and interpretative center (Marty et al., submitted b).

Abstract: Late Jurassic dinosaur footprint sites occur in several places in Northern Switzerland, forming two distinct megatracksites dating to the �Middle� Kimmeridgian (=Lower/Upper Kimmeridgian boundary) and the Late Kimmeridgian (Meyer, 2000) respectively. During archeological and paleontological prospection of the future highway «Transjurane» A16, a new dinosaur trackway site was discovered in Courtedoux, Northern Switzerland in February 2002. From May to September 2002 the �Section de paléontologie� excavated and documented the site over the whole width of the motorway on a surface of nearly 800 square meters. On this surface more than 500 single dinosaur footprints have been recognized and resolved into the trackways of at least 15 individual dinosaurs, mostly sauropods. Most of these sauropod footprints are somewhat reminiscent of a horse hoof print, regarded as manus prints and proportionally larger (about 50 centimeters in diameter) oval prints regarded as pes prints. Amongst the sauropod imprints so far 13 trackways have been identified and mesured. Some show a regular parallel alignement, which can be regarded as an evidence for gregarious behaviour among juvenile sauropods (Lockley et al., 1994b). The sauropod trackways are characterised by a narrow gauge, which is a diagnostic feature of the Parabrontopodus type (Lockley & Meyer, 2000). The Parabrontopodus trackway type from Courtedoux is the first in Switzerland. In all other Late Jurassic tracksites from Northern Switzerland the wide gauge Brontopodus ichnotaxon (Lockley et al., 1994a) is found. Although the few tridactyl footprints found on the surface are mostly poorly preserved, two trackways were identified. Both trackways have a very high pace angulation, suggesting theropod dinosaurs. The recently discovered tracksite can be dated by aspidoceratid ammonites found about 4 meters over the track-bearing laminites to the basal Upper Kimmeridgian. The Courtedoux site may thus correspond to the Lower/Upper Kimmeridgian boundary megatracksite, extending it for another 15 km to the northwest. The Courtedoux site is of major importance for Switzerland's dinosaur heritage. So far nearly 10�000 people have visited the site during open public days. Beside the excavation and scientific study of the site, which will be continued in2003, the 'Section de paléontologie' promotes the protection of the site. As it is located at one end of a viaduct of the highway it could possibly be protected underneath a bridge to form a future �geotop�.

Abstract: The �Section de paléontologie� is a new paleontological project. As a result of the construction of the new �Transjurane� highway, it�s foundation in february 2000 was initiated and supported by PD Dr. C. A. Meyer, Director of the Natural Museum Basel and Professor J.-P. Berger from the Departement of Geosciences, University of Fribourg. The �Section de paléontologie� was established to save and examine the paleontological heritage of the Jura Canton on the futur highway course. The project is hence financed for 95% by the FEDRO (Swiss Federal Roads Authority) and for 5% by the Jura canton. Similar archeological survey projects are common since quite a long time. However, this is the first time that paleontological heritage finds a similar acceptance in Switzerland, if not even Europe. During archeological and paleontological prospection on the future course of the highway, first dinosaur imprints have been discovered in Courtedoux in February 2002. The track-bearing level, situated at the base of a laminite bed, has been uncovered on a surface of about 50 m2 to have a first look at the potential of the site. It was obvious that tracks were abundant and formed trackways as well. During the main 2002 excavation phase, the trackbearing-level was uncovered over the whole width of the future highway on a surface of nearly 800 m2. Scientific documentation and studies are carried out by the �Section de paléontologie� under the supervision of PD Dr. C.A. Meyer (Basel) and Prof. M.G. Lockley (Denver, Colorado). So far it is possible to follow 13 narrow gauge sauropod and two theropod trackways on the level 1000 (Marty et al., 2002). Some of the sauropod trackways show a regular parallel alignement, which can be regarded as an evidence for gregarious behaviour among sauropods (Lockley et al., 1994). Further at least 4 other sauropod track-bearing levels, of which so far 2 levels contain trackways , have been discovered in the overlying laminite bed. These levels are going to be excavated and documented layer by layer on another 800 m2 during the year 2003. Beside the excavation of dinosaur tracks, the �Section de paléontologie� undertakes excavations in overlying marine layers as well. Invertebrates and remains of turtles, crocodiles, sharks and bony fishes have been dug out. Aspidoceratid ammonites (Orthaspidoceras schilleri), found about 4 meters above the track-bearing laminite bed, date the Courtedoux section to the basal Upper Kimmeridgian. The Courtedoux site may thus correspond to the Lower/Upper Kimmeridgian (Middle Kimmeridgian sensu Meyer, 2000) boundary megatracksite, extending it for another 15 km to the northwest. The Courtedoux tracksite is of major importance for Switzerland�s if not even world�s dinosaur heritage. So far nearly 10'000 people visited the site during open public days. The �Section de paléontologie� thus promotes the protection of the site. As it is located at one end of a viaduct of the highway it could possibly be protected underneath a bridge to form a future �geotop�.