The Bou Azzer-El Graara ophiolite has been interpreted as oceanic or backarc crust overlain by a calc-alkalic arc sequence or as a composite forearc and accretionary melange. Seventy-nine new major and trace element whole-rock analyses of the metavolcanic rocks from throughout the complex support the latter interpretation.The results of this study indicate that the Bou Azzer metavolcanics comprise three petrographically and geochemically distinct groups. 1.(A) A siliceous metavolcanic series, ranging from basaltic andesites to rhyolites with calc-alkalic characteristics, is the principal component of the northern section of the complex. It includes distinct quartz-bearing, rhyolite flows. Isolated massive pyroclastic layers are typically associated with this series. These rocks are interpreted as forearc basin volcanics and pyroclastics produced during late Proterozoic, north-dipping subduction.2.(B) Low-Ti metabasalts which display island arc tholeiitic affinities occur as isolated flows or blocks in most of the ophiolite. These rocks may represent fragments of the forearc basement below the siliceous series.3.(C) High-Ti metabasalts which range from enriched tholeiitic (Zr/Y<4) to mildly alkalic (Zr/Y>4) compositions are the principal volcanic block in the southern, melange-like terrane of the complex. These have high Ba and Sr contents (100–200 ppm average Ba, 260 ppm average Sr). They are identical to basaltic compositions from Tachdamt and Bleida on the southern margins of the ophiolite, which have previously been interpreted as a rifted continental margin sequence. These rocks could represent seamount volcanic products which have been thrust into an accretionary prism along the north-dipping subduction zone or rift margin basalts, which have been assembled in a tectonic melange as a consequence of a forearc-continent collision.Both the low-Ti and high-Ti metabasalt groups include samples previously identified as ocean-ridge or back-arc volcanics. However, there is no compelling evidence for the occurrence of these lava compositions in this region. The distribution of rock types within the ophiolite is most consistent with a previously proposed model which views the complex as three allochthonous terranes which were juxtaposed during collision to form the Bou Azzer-El Graara complex.

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   |wiki=    Wicri/Terre
   |area=    CobaltMaghrebV1
   |flux=    Main
   |étape=   Exploration
   |type=    RBID
   |clé=     ISTEX:AE800DF3BDABA2257D3432A2A715EAADBC4E60AF
   |texte=   Geochemistry and significance of metavolcanic rocks from the Bou Azzer-El Graara ophiolite (Morocco)
}}