ESR, OSL and TT-OSL dating methods were applied to samples collected from six of the Ancient Coastal Deposits (ACDs) along the southern Georgia Coastline. Samples were collected from the Princess Anne (the youngest and most seaward ACD), Pamlico, Talbot, Penholoway, Wicomico, and Okefenokee ACDs with the goal of determining the age of formation of these features. Ground Penetrating Radar (GPR) was used to determine the subsurface morphology and target lithologies for age determination. OSL and TT-OSL dating was attempted on samples collected from the youngest two ACDs, the Pamlico and Princess Anne, at McMaster Universities AGE Lab. ESR samples collected from all of the ACDs studied were measured at Florida State University as well as Osaka University. ESR analysis measured the Al signal, the Ti-Li signal, measured using two different methods, as well as the Ti-H signal. A number of low additive dose points were added to the ESR dose plan to attempt to create a better dose response curve for the low saturating Ti-H signal in attempt to better utilize the signal.
While the geochronological methodology did not prove useful for determining the age of all of the ACDs it did result in depositional age estimates for the Cypresshead Formation at 433-2978 ka and Satilla Formations at 243-417 ka using the Ti-Li ESR signal as a maximum age estimate. The GPR, ESR, and core data all point to the conclusion that the ACDs of the Georgia Coast are geomorphic modifications and not the result of a unique depositional process. Based on the discrepancy between the depositional age of the Cypresshead and Satilla Formations as determined by ESR in this study and the ages of the ACDs published by others from Georgia (Markewich et.al., 2013) or other areas of the Atlantic Coast (Wehmiller, 2004; Willis, 2006) it can be concluded that paleo sea-levels modified the Cypresshead and Satilla Formations in to the morphology seen today at some point after their initial deposition. / Dissertation / Doctor of Philosophy (PhD) / ESR, OSL and TT-OSL dating methods were applied to samples collected from six of the Ancient Coastal Deposits (ACDs) along the southern Georgia Coastline with the goal of determining the age of formation of these features. Ground Penetrating Radar (GPR) was used to determine the subsurface morphology and target lithologies for age determination. A number of low additive dose points were added to the ESR dose plan to attempt to create a better dose response curve for the low-dose saturation of the Ti-H signal in attempt to better utilize the signal.
While the geochronological methodology did not prove useful for determining the age of all of the ACDs, it did result in depositional age estimates for the Cypresshead Formation at 433-2978 ka and Satilla Formations at 243-417 ka. The GPR, ESR, and core data all point to the conclusion that the ACDs of the Georgia Coast are geomorphic features without unique depositional events.
| Identifer | oai:union.ndltd.org:mcmaster.ca/oai:macsphere.mcmaster.ca:11375/18685 |
| Date | January 2016 |
| Creators | Hendricks, Robert R. |
| Contributors | Rink, William, Jack, Earth Sciences |
| Source Sets | McMaster University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis |
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