Internal Architecture of an Incised Valley Formed within a Semi-Arid Setting, Baffin Bay, Texas

Aryal, Niranjan¹, Alexander Simms² (1) Oklahoma State University, Stillwater, OK (2) Oklahoma State University,

Baffin Bay, Texas, is a flooded late Pleistocene/Holocene incised valley of Petronila, San Fernando, and Los Olmos Creeks. Baffin Bay represents an “under-filled” incised valley that currently lies within a semiarid climate zone and is the site of both siliciclastic and carbonate depositional systems. In order to examine the internal architecture of an incised valley formed within a semi-arid setting, we collected 65 km of high-resolution seismic profiles and three cores up to 10 m in length aboard the R/V Trinity. This data was used to construct a Pleistocene/Holocene map of the incised valley and examine the sedimentlogical character of its fill. In its upper reach the incised valley achieves a depth of 28.5m. The fill contains mostly silt and carbonate mud with lamination of shell hash, algal mats, and fine sand. The architecture of this mixed siliciclastic/carbonate under-filled incised valley can be used as an analogue when producing from and searching for new petroleum reservoirs within semi-arid climatic settings.