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"Classic" field mapping in sedimentary successions, where lithostratigraphy, biostratigraphy and sedimentology meet, still has potential for producing answers to long‐standing problems in basin analysis. In the Northern Apennines of Italy, constraints on the slip rates of Early Jurassic rift faults, related to the embryonic separation of Eurasia and Gondwana, are provided by sedimentology and ammonite biostratigraphy, coupled with the field mapping of exposed tracts of the submarine escarpments and of the clinoform slopes which bordered carbonate footwall blocks. Slip rates of 600–1,000 m/Myr are here computed for Tethyan rift faults, producing >1 km of palaeostructural relief in ~2 million years (earliest Sinemurian: Bucklandi p.p. – Semicostatum p.p. zones). [ABSTRACT FROM AUTHOR]

A coral interpreted as a shallow-water zooxanthellate (z-) form has been recovered from the uppermost part of a condensed, pelagic carbonate platform-top succession, in levels with transitional characters between the Jurassic Bugarone Group and the Maiolica Formation, a calpionellid-bearing pelagic deposit. While the existence of z-corals in the Jurassic pelagic facies of northern Apenninic structural highs is well documented, with early Tithonian forms diagnostic of the lower layers of the photic zone, the species described in this paper is slightly younger (late Tithonian), possesses a different morphology and is known from typical reef facies. While this finding provides welcome evidence for the paleodepth interpretation of otherwise enigmatic facies, it also challenges our understanding of pelagic deposits, in paleoenvironments that have no modern counterparts. Unlabelled Image • A z-coral was recovered in upper Tithonian condensed pelagites on the Mt Nerone PCP. • Z -corals can constrain water paleodepth also in pelagic successions. • Ogilvinella is a typical reef coral suggesting a circa 30 m paleodepth. [ABSTRACT FROM AUTHOR]

The sedimentary successions exposed in northeast Calabria document the Jurassic–Early Cretaceous tectonic–sedimentary evolution of a former segment of the European–Iberian continental margin. They are juxtaposed today to units representing the deformation of the African and Adriatic plates margins as a product of Apenninic crustal shortening. A complex pattern of unconformities reveals a multi-stage tectonic evolution during the Early Jurassic, which affected the facies and geometries of siliciclastic and carbonate successions deposited in syn- and post-rift environments ranging from fluvial to deep marine. Late Sinemurian/Early Pliensbachian normal faulting resulted in exposure of the Hercynian basement at the sea-floor, which was onlapped by marine basin-fill units. Shallow-water carbonate aprons and reefs developed in response to the production of new accommodation space, fringing the newborn islands which represent structural highs made of Paleozoic crystalline and metamorphic rock. Their drowning and fragmentation in the Toarcian led to the development of thin caps of Rosso Ammonitico facies. Coeval to these deposits, a thick (> 1 km) hemipelagic/siliciclastic succession was sedimented in neighboring hanging wall basins, which would ultimately merge with the structural high successions. Footwall blocks of the Early Jurassic rift, made of Paleozoic basement and basin-margin border faults with their onlapping basin-fill formations, are found today at the hanging wall of Miocene thrusts, overlying younger (Middle/Late Jurassic to Late Paleogene) folded basinal sediments. This paper makes use of selected case examples to describe the richly diverse set of features, ranging from paleontology to sedimentology, to structural geology, which are associated with the field identification of basin-margin unconformities. Our data provide key constraints for restoring the pre-orogenic architecture of a continental margin facing a branch of the Liguria–Piedmont ocean in the Western Tethys, and for estimating displacements and slip rates along synsedimentary faults. [ABSTRACT FROM AUTHOR]