The east Texas continental shelf falls within the paleodrainage basin of the ancestral Trinity and Sabine rivers (Figure 4). These rivers have much smaller drainage basins, and therefore smaller sediment yields, than the Brazos and Colorado rivers. Their drainage basins are confined to east Texas, so these rivers may not have experienced the dramatic climatic changes that impacted west Texas during the last glacial cycle. This perhaps explains why the Trinity and Sabine rivers did not construct large deltas on the continental shelf during the last highstand. An early highstand Trinity delta has been inferred from onshore distributaries, but we have not observed an offshore delta. In fact, Thomas and Anderson (1995) have identified fluvial terraces with the Trinity River incised valley which they interpret as Stage 5 terraces, implying that the Trinity River occupied a single broad meanderbelt during the last highstand. This meanderbelt was later incised during the Stage 2 lowstand.