Tectonic Segmentation of the Mesozoic to Paleogene Malta Isolated Carbonate Platform: A Key to Rifting in the Central Mediterranean

The Mesozoic rifting of the western Neo‐Tethys opened in an E‐W direction resulting in N‐S trending transform faults in the Ionian oceanic crust and stretching of continental lithosphere in the Central Mediterranean. The Malta Escarpment marks the continent‐ocean boundary, along which the >200 km‐wide, Malta isolated carbonate platform (MICP) developed during the Mesozoic. The MICP is on the eastern margin of the Pelagian Block, part of the North African passive margin. Seismic, well, outcrop, gravity and magnetic data reveal that the MICP is tectonically segmented by NE‐SW trending listric faults parallel to the Medina Escarpment. These faults produced a series >20 to 100 km‐wide half grabens separated by narrow footwall blocks which emerged during lowstands of sea‐level. It is proposed that the segmentation is from crustal necking along the central part of the <300 km‐wide, Eastern Pelagian Slab (EPS) which extends from offshore Sicily to offshore Cyrenaica. The EPS is characterized by thinned continental crust (<25 km thick) bound by N‐S trending transform faults on its east and west. The crustal thinning is the result SE stretching of the North African passive margin, and abortive rifting in conjunction with active rifting of the Ionian oceanic crust. The Medina Escarpment evolved into a proto‐passive margin adjacent to hyper‐thinned continental crust of the Sirte Rise until Santonian continental convergence aborted the rifting. The northern ends of the transform faults were later reactivated as strike‐slip faults during the Neogene when the northern margin of the Pelagian Block transitioned into a foreland position.