Geodynamic events reconstructed in the Betic, Maghrebian, and Apennine Chains (central-western Tethys).

A synthetic study has been made to identify main tectono-sedimentary and geodynamic 42 events in central-western Tethys. For this, an interdisciplinary analysis has been performed on 43 successions belonging to tectonic units derived from Betic-Maghrebian-Southern Apennine “Flysch 44 Basin” domain. The stratigraphic records of the internal, external, and mixed successions deposited in 45 lateral basins of different chains show very similar characters, especially regarding: (a) 46 lithostratigraphy and ages; (b) kind and provenance of supplies (immature and supermature petrofacies 47 from internal and external margins, respectively); (c) presence of “mixed successions” (composed of 48 alternating internal and external petrofacies) attesting to clear palaeogeographic relationships between 49 opposite depositional systems; and (d) timing of the deformation. In addition, specific lithofacies reveal 50 correspondence with similar sedimentary events, such as: (1) very thick silicoclastic supply 51 concentrated in restricted time ranges indicating the main deformational phases in the margin/basin 52 systems; (2) levels rich in black shales, glauconian, siliceous, and volcaniclastic, widespread in the 53 study successions and linked to particular events at the Tethyan scale (anoxic periods, starvation- 54 upwelling, acid-intermediate penecontemporaneous volcanic activity, respectively). Tectonic influence 55 has also been recorded by means of unconformities and tectofacies (such as turbidites, slumps, and 56 olisthostromes, etc.), being correlated with the main deformational phases. Similar stratigraphic and 57 tectonic events have also been found in the Calvana Unit of Val Marecchia Nappe (Ligurides, northern 58 Apennine). Correlations of stratigraphic and tectonic events support the proposal of an evolutionary 59 geodynamic model involving the presence of a “Mesomediterranean microplate” in intermediate 60 position which acted during Africa-Europe convergence. The closing of central-western Tethys 61 occasioned the Betic-Maghrebian-Southern Apennine oceanic branch deformation and the birth of 62 perimediterranean chains during middle-late Miocene.