During the last transgression, the Colorado River constructed a large, sandy delta on the inner shelf wich is designated the SFU F delta. The transgressive systems tract consists of backstepping deltas, reefs, and
possible transgressive incised valley fill deposits.
Time thickness map of SFU F. SFU F is in black and is located updip of SFU E (in gray).
This map only shows the most western lobe of the Phase 1 transgressive
delta mapped by Snow (1998). Arrows indicate ancestral Colorado distributary
channels. The timing of reef development can be constrained to be between 11,000 and
11,500 years BP based on the radiocarbon dates of the Phase 1 delta (Snow, 1998). The area south of the delta is carpeted by transgressive marine muds of the "Texas Mud Blanket" (Shideler, 1976). These muds onlap and bury sandy highstand coastal deposits.
Near-shore
core dataset