Regional Extension and Genetic Conditions of the Salonta Sandstone Unit in the Darvas-Vésztö Trough and Békés Basin

Lux, Marcell ¹
(1)University of Miskolc, Miskolc, Hungary.

The objective of this study is to clarify the regional extension and genetic conditions of the Salonta Sandstone Unit in the Darvas-Vésztö Trough and Békés Basin which are important depressions at the Eastern part of the Pannonian Basin in Hungary.

The Lower Pannonian Salonta Sandstone Unit is the lower member of the Szolnok Sandstone Formation and represents a transition from the basal marls to the typical, sandy turbidites of the upper part of the formation. Many hydrocarbon exploration studies aimed at the upper parts of the Szolnok Formation while the lower parts were not examined in detail. This study is the first step of a detailed analysis.

On the basis of the available literature, exploration reports, 2D seismic surveys and well-logs, a basic seismic and sequence stratigraphic analysis was carried out, the paleogeographic environment was reconstructed and a schematic facies model was also created.

Based on the results of the seismic interpretation I constructed structure maps and a thickness map from which I drew conclusions regarding the extension of the Salonta sandstone sequence. Accordingly, the Salonta sandstone sequence wedges out on the more elevated parts of Battonya-Pusztaföldvár High (BPH), but continues to spill over the deeper seating parts of the BPH and extends into the Makó Trough. In the North and Northeast significant decrease in thickness can be observed.

The results of the basic seismic and sequence stratigraphic analysis have indicated, that the Salonta sandstone sequence has got a typical onlap pattern and was deposited during rising lake level. This can be confirmed by the literature and also by my own observations.

As for the paleogeographic environment I found that sediment supply from the Northwest was probably more dominant than those from Northeast and East. This is corroborated by evidence from the thickness map. References and my own observations (namely the hummocky clinoform internal reflexion pattern and thickness map) suggest that the mud/sand rich sediments of the Salonta sandstone sequence were transported into deeper parts of the basin - as indicated earlier - through troughs between basement highs. Consequently the stacked turbidite lobes and subaquaeous fans could be derived from multiple sources within the dominant route of sediment supply.

AAPG Search and Discovery Article #90135©2011 AAPG International Conference and Exhibition, Milan, Italy, 23-26 October 2011.