Mesozoic tectonics and volcanism from Tethyan rifted continental margins in western Sicily

Abstract

Tectonic and volcanic features from the Jurassic-Cretaceous carbonate successions of Rocca Busambra, Balatelle Mount and Vicari-Roccapalumba (central-western Sicily), are here described. These areas represent the easternmost outcrops of the Trapanese domain in Sicily. The Trapanese succession consists of shallow to deep-water Meso-Cenozoic deposits formed in a carbonate platform to pelagic plateau depositional setting. Detailed field work and structural analysis detected indicate the occurrence of paleofaults with different orientation, unconformity surfaces, lateral facies changes, resedimented materials and volcanic products (pillow lavas and tuffitic deposits). These data combined with facies and physical-stratigraphy analysis, allow for the distinction of different tectono- stratigraphic settings. A structural low, represented by Monte Balatelle outcrop, is filled with thick bodies of pillow lava and reworked deposits; it appears bordered by two main structural highs: Rocca Busambra, an articulate carbonate pelagic platform with stepped fault margin, and Vicari- Roccapalumba a flank of a structural high, where the volcano-clastic deposits interlayered with reef- reworked materials suggest the occurrence of a submarine volcano, evolving to an atoll-type carbonate shelf setting. Tectonic pulses and magmatic events punctuated the sedimentary evolution during Early Jurassic, Middle-Late Jurassic, Early and Late Cretaceous. The horst and graben connected by steeped margin reconstructed morphostructural setting and the occurrence of distinct types of volcanic products suggest that the study areas could represent a sector of the continental margin near the basinal areas of the Jurassic-Cretaceous southern Tethyan passive margin.