As so ci ate ed i tor: Jacek Grabowski We pres ent ev i dence for the up per most Ju ras sic-low est Cre ta ceous in ter val in Cri mea, coastal south ern Ukraine. Three facies zones are dis tin guished in the up per Dvuyakornaya and the Mayak for ma tions of the east ern Cri mean Pen in sula: basinal, slope and toe-of-slope zones. In this in ter val we iden tify the low est Berriasian Jacobi and Grandis subzones of authors, in ex panded form, ex ceed ing 160 metres in thick ness. We pres ent new magnetostratigraphic in ter pre ta tions, and iden tify two nor mal and two re versed po lar ity in ter vals, as signed to M19n, M18r, M18n and M17r, with M19n2n, M19n1r and M19n1n iden ti fied in the up per most Dvuyakornaya For ma tion. In the Mayak For ma tion we re cord the top of M19n.1n, with M18r, M18n and a thick M17r above. In these two for ma tions com po nent calpionellid spe cies have been iden ti fied which char ac ter ise the Alpina, Ferasini and Elliptica subzones (Calpionella Zone). In M19n, the FADs of the cal car e ous nannofossils Hexalithus strictus, Cruciellipsis cuvillieri, Nannoconus wintereri, N. steinmannii mi nor and N. kamptneri mi nor are found, which is con sis tent with other Tethyan re gions. N. steinmannii steinmannii and N. kamptneri kamptneri first appear in M18r at Ili Burnu. Spec i mens of the ap par ently Tithonian foraminiferan in dex Anchispirocyclina lusitanica are found, but in the Berriasian lower Mayak For ma tion.
An exceptional, briefly exposed section across the boundary between the Pieniny Klippen Belt (PKB) and the Central Carpathian Paleogene Basin (CCPB) in Eastern Slovakia showed that the contact is formed by a single, subvertical fault plane. Whereas the Oligocene CCPB deposits exhibit only weak deformation with S-verging fold-and-thrust structures, the Cretaceous PKB sediments are internally strongly sheared with scaly fabric and numerous calcite veins. It is inferred that the PKB suffered strong thrusting-and wrenching-related deformation in pre-Oligocene times, while the Early Miocene oblique backthrusting resulted in exhumation of the PKB and formation of its steep fault boundaries.
We present a stratigraphic investigation of a Hauterivian to Cenomanian hemipelagic succession from Col Puez, in the Dolomites (Southern Alps, northern Italy). A composite section of seven segments was studied with bio-, magneto-, and chemostratigraphy, which enabled detailed and robust age calibration of the Puez succession. It also revealed the paleoceanographic history and helped identify the important global climatic events of that period. The age of the Lower Cretaceous Puez Formation in the Dolomites is refined as late Hauterivian to early Cenomanian. Ammonoids provide a detailed biostratigraphic subdivision that forms the basis for analyses of the faunal distribution and the paleoenvironmental evolution of basins and plateaus across the Tethys. The succession consists of facies similar to those of coeval units in the Tethys, apart from the late Barremian to late Aptian interval, which is marked by a major hiatus followed by a few-metersthick redbed of late Aptian age. The Lower Cretaceous was characterized by a weak (~1‰) positive δ 13 C trend, punctuated by a positive shift in the late Hauterivian corresponding to the Faraoni Level. Oxygen isotope values show a decreasing trend from the Hauterivian to the Albian/Cenomanian, which mirrors a long-term increasing trend in paleotemperatures from ~15-18°C to ~25-30°C. This is in agreement with global paleotemperature reconstructions for this period representing the onset of mid-Cretaceous super-greenhouse conditions. Nonetheless, no black shale occurs at the intervals equivalent to Aptian-Albian oceanic anoxic events (OAE), suggesting unique paleoceanographic conditions (enhanced current activity on a submarine height) on the Trento Plateau area during the mid-Cretaceous.
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