GSA Connects 2021 in Portland, Oregon

Paper No. 156-17
Presentation Time: 9:00 AM-1:00 PM


YAGER, Stacy L., BERGEL, Emily, CALDWELL, Lauren P., FIGHTS, Ramey, HEUER, Jarod S., HUMPHREY, Sarah A., MCCARTY, Amanda E., MONTGOMERY, Jaia and FLUEGEMAN, Richard, Environment, Geology, and Natural Resources Department, Ball State University, Fine Arts Building (AR), Room 117, Muncie, IN 47306-4554

Many of the important sequence stratigraphic models for the eastern Gulf Coastal Plain incorporated the Little Stave Creek section as foundational data. The Little Stave Creek section is no longer available for direct study but geological data can be added to existing information on the section. Archival samples collected from carefully measured sections with identification of sequence boundaries, transgressive surfaces, and maximum flooding surfaces can allow paleontologists to overlay data on existing stratigraphic models of the sedimentary sequences in the Little Stave Creek section.

Benthic foraminifera were collected from 59 archival samples from Little Stave Creek, Clarke County, Alabama with the goal of testing the sequence stratigraphic model for the Claiborne and lower Jackson Groups in the eastern Gulf Coastal Plain. The section was described and measured in 1988 and important stratigraphic surfaces were located at that time. The samples used in this study were collected from the Tallahatta, Lisbon, Gosport, Moodys Branch Formations, and the North Twistwood Creek Clay Member of the Yazoo Clay and include all or part of 6 depositional sequences. Samples were washed and processed for microfossils. Foraminifera were picked and identified in each sample.

In the studied samples, species of Quinqueloculina, Triloculina, Textularia, Gaudryina, Clavulinoides, Discorbis, Reusella, Lenticulina, Nonion, Nonionella, Hanzawaia, Cibicidina, Spiroplectammina, Siphonina, Cibicidoides, Uvigerina, Bulimina, and Bolivina account for over 50% of benthic foraminifera identified. The census data were subjected to hierarchal cluster analysis. Six distinct clusters were recognized in the samples at Little Stave Creek. Five of these have been associated with depth controlled benthic foraminiferal assemblages identified in the Moodys Branch and Yazoo Formations in the Mossy Grove and Young cores of Mississippi. The samples associated with the sixth cluster show evidence of reworking.

The results show the succession of benthic foraminiferal assemblages in the Little Stave Creek section changes in bathymetry expected are consistent with the sequence stratigraphic model for the Lutetian and Bartonian units of the eastern Gulf Coastal Plain with minor fluctuations in this pattern related to parasequences.