History of western Tethys Ocean and the birth of the circum-mediterranean orogeny as reflected by source-to-sink relations

Abstract

A broad region of Mesozoic to Cenozoic tectonism along the western and central Circum-Mediterranean (CM) margins, from southern Spain (Betic Cordillera) to the northern Morocco (Rif) and Italy (Apennines), includes huge volumes of sedimentary record since the Late Paleozoic. These sediments are contemporaneous and related with the fragmentation of the Pangean supercontinent due to the rifting and progressive closure, as well as the following birth of the CM orogeny. The composition and stratigraphic relations of clastics in diverse sedimentary basins of the CM region reflect a complete record of provenance relations related to the progressive destruction of the Neotethyan Ocean and plate convergence between the two major plates of Europe and Africa, and Iberia, Adria and Mesomediterranean micrplates located between them. The changing nature of clastic wedges reflects the provenance relations from different source rocks involving obduction of the oceanic lithosphere, the uplifted Alpine-Mediterranean Chains, and the accreted previously deformed Mesomediterranean Microplate (AlKaPeCa), as well local neovolcanic sources, within the spatial and temporal evolving geo-puzzle terranes of the CM orogeny. The provenance evolution of sediment provides insights into how plate convergence and continental collision direct the sediment dispersal pathway in Cenozoic basins due to closure of eastern and southern Alpine-Tethyan remnant ocean basins and to the dual dispersal pathways from the previously born Alps and the nascent AlKaPeCa at the expenses of the previously deformed Mesomediterranean terranes. The source-to-sink relations testify episodic deformation events, diachronous Tethyan basin development, differentiate sediment provenance from exhumed and uplifted Alpine and CM orogens, and palaeogeographic rearrangement of crustal blocks along the nascent Mediterranean region.