Taphonomy and ages of bivalve shells from San Salvador Island, Bahamas

TitleTaphonomy and ages of bivalve shells from San Salvador Island, Bahamas
Publication TypeConference Paper
Year of Publication2008
AuthorsPruss, SB
Corporate AuthorsPruss, SB
Date Published2008
PublisherGeological Society of America (GSA), Boulder, CO, United States (USA)
Conference LocationUnited States (USA)
Keywords10, abrasion, absolute age, Bahamas, beachrock, Bivalvia, C-14, carbon, carbonate rocks, Caribbean region, Cenozoic, Chione, dates, Gastropoda, Glycymeris, Heterodonta, Holocene, interpretation, Invertebrata, Invertebrate paleontology, isotopes, lithification, living taxa, Mollusca, Quaternary, radioactive isotopes, San Salvador, sedimentary rocks, sediments, shells, taphonomy, upper Holocene, Veneridae, Veneroida, West Indies

Paleontological interpretations of taphonomic processes can be complimented by examining abrasion and age of shells in modern settings. A preliminary analysis of the ages of bivalves from Haitian Boat Beach (just east of Barkers Point, northwest coast of San Salvador Island, Bahamas) provides a range of ages of shell material exposed on modern beaches of San Salvador Island and provides estimates of the timing of beach rock lithification. At Haitian Boat Beach Beach, bivalves and gastropods were collected from shell accumulations preserved on the beach as well as within a single 3 to 5-cm thick horizon of beach rock. The ages of 2 valves (Genus Chione) from the beach and 4 valves (Genus Chione and Genus Glycymeris) from the beach rock were analyzed. Two of the most abraded shells were selected for analysis from the beach in an attempt to get a maximum age of beach shell material. These shells were radiocarbon dated by measuring carbon-14 at NOSAMS and converted to calendar years using the CALIB program of Stuiver and Reimer (1993). Two abraded valves collected from the beach yielded calendar year ages BP of 512 and 549 years. The beach rock valves yielded calendar year ages BP of 143, 129, and 1628. These results suggest lithification of beach rock was initiated