The Guerrero Composite Terrane of western Mexico: Collision and subsequent rifting in a supra-subduction zone

The Guerrero Composite Terrane of western Mexico is the second largest terrane in North America. Mostly characterized by submarine volcanism and formed by five terranes, the Guerrero records vast and complex subduction-related processes influenced by major translation and rifting. It is composed of the Teloloapan, Guanajuato, Arcelia, Tahue, and Zihuatanejo Terranes. The Teloloapan Terrane is made up of Lower Cretaceous island-arc (IA) andesitic to basaltic submarine lava flows, interbedded with limestone and shallow-marine volcaniclastic rocks. The Guanajuato and Arcelia Terranes are characterized by Lower Cretaceous supra-subduction ophiolite successions formed by deep-marine volcanic and sedimentary rocks with mid-oceanic-ridge basalt (MORB), oceanic-island basalt (OIB), and island-arc basalt (IAB) signatures. These two terranes are placed between the continent and the more evolved arc assemblages of the Zihuatanejo Terrane. The Tahue Terrane is composed of Paleozoic accreted arc and eugeoclinal sedimentary rocks, Triassic rift-related metaigneous rocks, and overlain unconformably by pillow basalts, limestone, and volcaniclastic rocks. The Zihuatanejo Terrane was formed by Triassic ocean-flank to ocean-floor assemblages accreted in Early Jurassic time (subduction complexes). The subduction complexes are overlain by Middle Jurassic–evolved volcanic arc rocks, which are in turn unconformably overlain by Early and Late Cretaceous subaerial and marine arc-related volcano-sedimentary assemblages.