Geologia Croatica, Vol. 69 No. 2, 2016.
Original scientific paper
https://doi.org/10.4154/GC.2016.16
Pannonian ostracods from the southwestern Transylvanian basin
Erika Kovács
; Geological Institute, Slovak Academy of Sciences, Banská Bystrica
Imre Magyar
; MOL, Budapest
Orsolya Sztanó
; Eötvös Loránd University, Budapest
Radovan Pipík
; Geological Institute, Slovak Academy of Sciences, Banská Bystrica
Abstract
Pannonian (Late Miocene) ostracods were investigated from 7 outcrops, exposing deep-water lacustrine sediments along the western margin of the Transylvanian Basin. Sedimentological patterns in the outcrops indicate deposition in sublittoral to profundal environments where fine-grained, suspension fall-out sediments are intercalated with various types of mass transport deposits, most commonly turbidites. The ostracod fauna, consisting of 30 taxa, is dominated by endemic species of the brackish Lake Pannon. The assemblages indicate a mixture of deep-water (sublittoral to profundal) species, such as Paratethyan Candoninae, and shallow-water (littoral) species, belonging to Cyprideis, Loxoconcha, Amnicythere and Hemicytheria. The mixed character of the assemblages is most probably a consequence of the reworking of littoral specimens into deeper environments, a phenomenon also observed in the molluscan fauna from some of the investigated outcrops. Alternatively, some endemic and extinct species of the littoral genera might have adapted to the deep-water environment. A significant decrease in the abundance and diversity of ostracods from west to east is interpreted reflecting increasingly distal environments. The ostracod fauna indicates the Hemicytheria hungarica (2 outcrops), Hemicytheria tenuistriata (3 outcrops), and Propontoniella candeo Zones (2 outcrops) of the lower Pannonian Slavonian Substage.
Keywords
Late Miocene; Pannonian; Transylvanian Basin; biostratigraphy; ostracods
Hrčak ID:
162233
URI
Publication date:
30.6.2016.
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