Berthoud 241/ Zoom, 4PM, Thursday, March 2, 2023
Laterally Accreting Slope-channels, Cyclic Steps, and Sediment Waves in a Not-So-Deep but Dynamic Basin, Mississippian Fort Payne Formation, Kentucky-Tennessee
Abstract: The Lower-Middle Mississippian Fort Payne Formation in south-central Kentucky consists of carbonate-shale clinothems, which initiated along the abandoned, subaqueous delta front of the Borden Formation and prograded ~50-70 km seaward over a span of about 10 my. Although the water depths were less than 150-200 m, the foresets-toesets are inclined 1-8o basinward (S-SW) and contain numerous slope channels filled with a wide variety of sediment gravity-flow deposits. Seaward, the clinothems transition into a 100 km wide carbonate sediment wave field.
This study documents lateral/vertical facies relationships and architecture of (1) slope channels filled with laterally accreted bedsets comprising high-density turbidites, hybrid-event beds and debrites and (2) slope clinothems that contain interpreted cyclic-step deposits, and (3) sediment-waves of varying scale in the bottomsets that are mantled by subcritical to supercritical flow deposits. Possible processes for sediment-wave formation include (1) cascading density currents from adjacent hypersaline shelf to the north, and/or (2) hyperpycnal flows generated from the Borden-Price-Grainger subaerial shelf-delta systems to the northeast.
This lecture is scheduled in a hybrid format. If you would like to join the meeting please:
Join from PC, Mac, Linux, iOS or Android: https://mines.zoom.us/j/95570863571?pwd=alk0c1RQTHc0enZZT2JKaCtaRE8vQT09
Meeting ID: 955 7086 3571
Password: 035402
The Van Tuyl lectures are scheduled at 4-5pm in BE 241/ Zoom (hybrid format), and after the lecture there will be a get-together from 5-6pm in BE 243 with pizza and sodas.