Naslov
An Early Miocene (?) brackish-water Basin in Eastern Hungary

Autori
Magyar, Imre ; Szuromi-Korecz, Andrea ; Nusszer, András ; Sütő-Szentai, Mária ; Nagy-Bodor, Elvira ; Bakrač, Koraljka ; Böhme, Madelaine ; Nagymarosy, András

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
The 4th international workshop on the Neogene from the Central and South-eastern Europe, Abstracts and Guide of Excursion / Kyška Pipik, Radovan ; Starek, Dušan ; Stanova, Sidonia - Banska Bistrica : Geological Institute, Slovak Academy of Science ,, 2011, 12-13

Skup
The 4th international workshop on the Neogene from the Central and South-eastern Europe

Mjesto i datum
Banská Bystrica, Slovačka, 12.09.2011. - 16.09.2011

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
Eastern Hungary; Early Miocene; brackish water

Sažetak
The Derecske basin, located in Eastern Hungary, is one of the deepest subbasins of the larger Neogene Pannonian Basin System. It is bounded by pronounced NE-SW oriented strike-slip faults and opened as a pull-apart basin. At the base Neogene level, the Derecske basin consists of two subbasins. The deeper, northern subbasin is filled dominantly by Late Miocene Lake Pannon deposits. The shallower, southern subbasin, however, was considered to have been filled with Middle Miocene (Badenian) marine sediments below the Upper Miocene lacustrine sequence. The southern subbasin has recently been tested by several drillings exploring for gas in the Middle Miocene sequence. Below fossiliferous marine Badenian biogenic limestone (Leitha limestone), these drillings penetrated a thick tuffaceous, sandy, silty, clayey sequence. Micropaleontological investigations of the core samples yielded strongly degraded phytoclasts, some identified as dinoflagellates, and poorly preserved ostracod valves, being dominated by candoniid species. In both groups, the recognized taxa are very similar to, or identical with Late Miocene Lake Pannon endemic forms, namely various species of Spiniferites, Pontiadinium, Amplocypris, Hungarocypris (? Herpetocyprella), and Bakunella. Foraminiferal test linings also occur. The samples were poor in nannoplankton, only sporadic occurrence of Helicopontosphaera kamptneri, Coccolithus pelagicus, and Sphenolithus moriformis was recognized. Other fossils include fish vertebrae (maybe belonging to a perch), fish teeth (a large pharyngeal tooth of a ?carp), percoid fish scales, red algae, and as yet unidentified nannofossils. The overall fossil content suggests brackish water depositional environment, but its age is still uncertain. The Badenian limestone cover of the formation indicates that it cannot be younger than Badenian, but most of the Badenian occurrences in the vicinity are marine deposits. Therefore, an Early Miocene age (Ottnangian? Karpatian?) seems most probable, although the paleogeographic context (isolation of the basin) and the striking resemblance of some fossils to Lake Pannon endemic taxa are poorly understood and leaves the stratigraphic position and age issue open to discussion.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

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