Constraining Grain Size Distribution of the Middle Caicos Blue Hole Storm Deposits
Description/Abstract/Artist Statement
Paleotempestology, or the study of past storms, uses natural archives like sediment cores to reconstruct past storm events for the last few thousand years. Sediment cores from coastal basins, like blue holes, have layers of coarse material interspersed among background fine sediments. These coarser layers (aka event layers) indicate the passage of storms with enough strength to move coarser grains into a blue hole. In this work, we explore reconstructing paleostorm intensity using sediment samples from storm event layers identified within a transect of three sediment cores taken across a blue hole off the southern coast of the Middle Caicos Island in Turks & Caicos. If there is a ocean-to-island side fining sequence of the sediment across storm layers in our transect pushed into the blue hole by storm surge, there is potential for using an advective settling model to reconstruct storm intensity. Using a CAMSIZER X2, we ran 63 event layer sediment samples and recorded their grain size distribution. We compared the distribution curves across the transect to determine if events demonstrate a fining sequence. Results indicate that only a third of the events follow the expected ocean-to-island fining sequence. The vast majority of storm events do not create an ocean-to-island fining sequence across our transect suggesting a need to examine a more complex model of deposition. We propose that sediment enters the blue hole in a different direction depending on the orientation of the storm, rather than just from the ocean-side.
Faculty Advisor/Mentor
Elizabeth Wallace
Faculty Advisor/Mentor Department
Ocean and Earth Sciences
College Affiliation
College of Sciences
Presentation Type
Poster
Disciplines
Geomorphology | Other Earth Sciences
Session Title
Poster Session
Location
Learning Commons Lobby @ Perry Library
Start Date
3-30-2024 8:30 AM
End Date
3-30-2024 10:00 AM
Constraining Grain Size Distribution of the Middle Caicos Blue Hole Storm Deposits
Learning Commons Lobby @ Perry Library
Paleotempestology, or the study of past storms, uses natural archives like sediment cores to reconstruct past storm events for the last few thousand years. Sediment cores from coastal basins, like blue holes, have layers of coarse material interspersed among background fine sediments. These coarser layers (aka event layers) indicate the passage of storms with enough strength to move coarser grains into a blue hole. In this work, we explore reconstructing paleostorm intensity using sediment samples from storm event layers identified within a transect of three sediment cores taken across a blue hole off the southern coast of the Middle Caicos Island in Turks & Caicos. If there is a ocean-to-island side fining sequence of the sediment across storm layers in our transect pushed into the blue hole by storm surge, there is potential for using an advective settling model to reconstruct storm intensity. Using a CAMSIZER X2, we ran 63 event layer sediment samples and recorded their grain size distribution. We compared the distribution curves across the transect to determine if events demonstrate a fining sequence. Results indicate that only a third of the events follow the expected ocean-to-island fining sequence. The vast majority of storm events do not create an ocean-to-island fining sequence across our transect suggesting a need to examine a more complex model of deposition. We propose that sediment enters the blue hole in a different direction depending on the orientation of the storm, rather than just from the ocean-side.