Contribution
Jurassic–Cretaceous transition in the Transdanubian Range (Hungary): integrated stratigraphy and paleomagnetic study of the Hárskút and Lókút sections
Lodowski, Damian Gerard; Pszczółkowski, Andrzej; Szives, Ottilia; Főzy, István; Grabowski, Jacek
Newsletters on Stratigraphy Volume 55 Number 1 (2022), p. 99 - 135
publié: Jan 14, 2022
publication en ligne: Apr 15, 2021
manuscrit accepté: Feb 15, 2021
révision final du manuscrit reçu: Feb 4, 2021
révision du manuscrit demandée: Jan 11, 2021
manuscrit reçu: Oct 23, 2020
ArtNo. ESP026005501003, Prix: 29.00 €
Abstract
A high-resolution stratigraphic calibration is presented using biostratigraphic (calpionellids, calcareous dinoflagellates, calcareous nannofossils), magnetostratigraphic and chemostratigraphic (δ13C, Al) techniques on the uppermost Jurassic–lowermost Cretaceous sedimentary successions from Hárskút and Lókút in the Bakony Mountains (Transdanubian Range, Hungary). These localities are characterized by noticeably distinct facies developments, despite their geographic proximity. Relatively condensed deposits of early Tithonian–early Valanginian age (ca. 15 m thick; M22r–M13r magnetozones) in the Hárskút succession revealed stratigraphic discontinuities; however, our methodology allowed us to identify hiatuses and condensation levels within the magnetostratigraphic record. The Tithonian–Berriasian boundary, marked by the base of the Alpina calpionellid Subzone, falls in the M19n magnetozone, below the base of the NC0 calcareous nannofossil Zone. In turn, the Berriasian–Valanginian boundary, marked by the base of the Calpionellites darderi calpionellid Subzone, is located in magnetozone M14r, below the base of the NC3 nannofossil Zone. A continuous record of Maiolica-type lower Berriasian limestone is exposed in the Lókút succession, between magnetozones M21r–M17n. A consistently decreasing lithogenic influx throughout the Tithonian–lower Berriasian is correlated with a Tithonian trend of climate aridization, while elevated upper Berriasian influxes primarily correspond to tectonic activity within the Neotethyan Collision Belt. The demise of the Saccocoma microfacies and the timing of Nannofossil Calcification Events are interpreted as both mutually related to paleoceanographic changes.
Mots-clefs
Jurassic/Cretaceous boundary • integrated stratigraphy • magnetostratigraphy • biostratigraphy • paleoenvironmental interpretation • paleomagnetism