Application of seismic stratigraphic analysis to high-resolution sparker profiles from Corpus Christi Bay, on the central Texas Gulf Coast, allows the development of a three-dimensional model of Holocene sedimentation in the study area. To establish a time-stratigraphic framework for the seismic sequence, a regional basal unconformity was picked as the lower sequence boundary and the sediment/water interface was defined as the uppermost boundary.

The seismic sequence is subdivided into discrete seismic facies based on reflector configuration, geometry, and bounding relations. Facies delineation allows the development of a model seismic facies tract composed of a lowermost complex/chaotic-fill facies, bounded by the subjacent regional unconformity, grading upward into an onlap fill facies, which then grades into an overlying parallel/subparallel/divergent facies.

Based on lithologic and textural data from borehole logs, a correlative sedimentary facies tract is found to consist of a fluvial/channel-fill facies, unconformably overlying a subjacent erosional surface and grading upward into a deltaic facies, which then grades into the uppermost bay-estuarine facies.

Chronostratigraphically, the lower, bounding unconformity is correlative with the last Pleistocene (late Wisconsin) lowstand of sea level. At approximately 10,000 years B.P., rising sea level associated with the Holocene transgression began to flood the erosional valleys, causing a gradual flux from fluvial to deltaic deposition. With continued sea level rise, the deltaic environment shifted landward (moving up the drowned valley) and bay-estuarine conditions began to dominate as sea level approached stillstand, about 4,500 years B.P. Aggradational bay fill has been the dominant mode of sedimentation since that time.

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