Meiofauna, trace metals, TOC, sedimentology, and oxygen availability in the Late Miocene sublittoral deposits of Lake Pannon

Abstract

The Late Miocene fine-grained deposits have been investigated in the Vienna Basin to attest oxygen availability for infauna and epifauna in the sublittoral of the long-lived Lake Pannon. A clay and fine silt of the deeper lacustrine facies of a bay passed vertically into a silty clay, silt, and fine sand rhythmic deposition reflecting successive progradation of brackish prodelta to distal delta front colonized by a dense benthic population. A fully oxygenated environment is supposed in the Congeria subglobosa Beds and prodelta accentuated by ichnofauna, ostracods, and abundant in taxa and specimens, low total organic content, and trace elements concentration. A limited anoxic event caused by temporarily worsened circulation has been detected in non-calcareous greyish-blue homogenous clay with a noticeable high concentration of Ni, Co, and Pb coupled with absence of fossils, bioturbation, and low total organic carbon content.

Sedimentary architecture and depositional controls of a Pliocene river-dominated delta in the semi-isolated Dacian Basin, Black Sea

“…These coarser structureless sediments were transported into the basin over long distances during intermittent sand influxes. As in previous studies (Starek et al, 2010;Hampson et al, 2011), these sandstones are interpreted as storm deposits.…”

“…The convolute bedding could have been created when the sandstones were rapidly deposited on the underlying water-saturated mudstones, causing an expulsion of the fluids contained in the mud (Oliveira et al, 2009). The shell-rich sandy beds (Sfg) sporadically intercalated in this facies association suggest, here as well, storm deposits (Starek et al, 2010;Hampson et al, 2011).…”

Miocene burrows of the Ghost Crab Ocypode and their environmental significance (Mykolaiv Sands, Fore-Carpathian Basin, Ukraine)

“…This would provide a plausible explanation for the variable thickness of the Mykolaiv Sands recorded throughout the area of their occurrence (see Teisseyre 1938;Pazdro 1953;Wysocka 2002). A similar environmental interpretation, based on the Ocypode burrows, has recently been inferred for the Late Miocene lacustrine-deltaic sequence of the eastern Vienna Basin in Slovakia (Starek et al 2010;Šimo et al 2011, p. 48).…”

Upper Miocene Pannonian sediments from Belgrade (Serbia): new evidence and paleoenvironmental considerations

“…Analogous forms of Amnicythere species are living in the sublittoral zones of the Black Sea and the Caspian Sea in brackish environments as well as in more freshwater bays (Cziczer et al 2009). Similar to this, recent Cypria species are generally freshwater forms but can tolerate mesohaline conditions (Meisch 2000;Starek et al 2010). There is other evidence that confirms this model (see the occurrence of different molluscs).…”