See more from this Division: Topical Sessions
See more from this Session: Late Quaternary of the Northern Gulf of Mexico Margin: Climate Change, Sea-Level Change, and the Depositional Record
Abstract:
The central and inner submerged shelves from Atchafalaya Bay to the southern edge of the Colorado-Brazos complex and the Rio Grande delta are devoid of significant Pleistocene-Holocene deposits, save cross shelf valley fill. However, on the upper shelf break and the inner and central South Texas shelf up to 50 meters of sediment have accumulated during the Late Pleistocene-Holocene sea level rise. The framework of the south Texas shelf, define by seismic stratigraphy, revels that there have been two sedimentary processes which have dominated to the formation of this part of the shelf: sand transport whose variation can be tied world wide climate variation and clay transport delivered to the shelf during annual seasonal change. Each of process has lead to the construction of unique sedimentary facies clearly defined in the seismic profiles. Coupling these sedimentary facies to the recently published sea level curve by Balsillie and Donoghue paints a clear picture of the interplay of these end-member processes to the development of the South Texas Shelf. The seismic-stratigraphy and sea level curve also explains the formation of the shelf edge reefs along the South Texas, forming during the lower sea level of the Younger Dryas.
See more from this Division: Topical Sessions
See more from this Session: Late Quaternary of the Northern Gulf of Mexico Margin: Climate Change, Sea-Level Change, and the Depositional Record