Palynology and stratigraphic characterization of subsurface sedimentary successions in the Sicanian and Imerese Domains—Central Western Sicily

•Palynostratigraphic study of Lercara Complex, Mufara Fm. and Scillato Fm.•Age interval: Permian to late Triassic.•Geological framework and lithological description of the studied succession.•Correlation between the well sections and outcropping composite section.

According to past publications, the deep-water Mesozoic successions that outcrop in the Sicilian chain area belong to different stratigraphic-structural domains: the Sicanian and Imerese thrust systems. These were investigated in the subsurface by means of many wells, most of which were drilled in the 1960s.The two domains share a common basement represented by the Lercara Complex (Permian–Ladinian), the Mufara Formation (Carnian) and the Scillato Formation (Upper Carnian–Rhaetian).Palynological studies carried out by Eni S.p.A. on exploration wells such as Creta 1 and Platani 2 allowed a better stratigraphic characterization of the Upper Triassic Mufara and Scillato formations. Well Casteltermini 1, drilled by Eni S.p.A. in 2009, crossed a system of two superposed tectonic nappes and reached the deep Permo-Triassic basement composed by the Lercara Complex and the Mufara Formation. The palynological analysis performed on these successions, indicates that the Lercara Complex is composed of at least four units. The lower unit is Permian in age, ranging from a questionable ‘mid Artinskian–Kungurian’ to Roadian–early Wordian. It is followed by a second thinner unit dated late Wordian–Capitanian. Above this Permian well section a third lithologically well defined unit of indeterminate age was encountered. An uppermost and fourth unit yielded Ladinian microfloras and was kept distinct from the overlying Mufara Formation of early–late Carnian age. The Lercara Complex and the Mufara Formation are overlain by the lower–middle Eocene Scaglia-type sediments (Amerillo Formation) by means of a tectonic contact.The age constraint provided by palynology and the accurate lithostratigraphic characterization of the Middle Permian to Middle Triassic Lercara Complex, intersected by well Casteltermini 1, suggest several and significant similarities with the Sosio Valley sediments outcropping near to Palazzo Adriano.