Cadi Ayyad University Faculty of Sciences Semlalia Department of Geology Prince Moulay Abdellah Boulevard. , P.O. Box 2390, Marrakech 40 000 Morocco Phone (office) : +212 524 43 46 49 (442) Fax: + 212 524 43 74 11
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Centro de Geologia da Universidade de Lisboa Faculdade de Ciências.Universidade de Lisboa Bloco C6, 3º Piso, sala 6.3.57 Campo Grande 1749-016 Lisboa Portugal Phone: + 351 217500000 (x 26357) Fax: + 351 217500119
Abstract: The morphology, internal architecture and emplacement mechanisms of the Central Atlantic Magmatic Province (CAMP) lava flows of Argana Basin in Morocco are presented. The volcanic pile was produced by two volcanic pulses. The first, represented by the Tasguint Formation, corresponds to a succession of 3–13 individual flows created by 1–8 eruptions; the second, Alemzi Formation, is composed of 2–7 individual flows formed by 1–4 eruptions. These formations, geochemically distinct, are separated by thin silty or sandy horizons or by palaeosols. They include ‘compound pahoehoe flows’ and ‘simple flows’. The first type is almost exclusive of the lower formation, while the second type dominates the upper formation. The lava flows show clear evidence of endogenous growth or ‘inflation’. The characteristics of the volcanic pile suggest slow emplacement during sustained eruptive episodes and are compatible with a continental basaltic succession facies model.
