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SKELETAL REMAINS ON THE SLOPE & SHELF INITIAL CARIBBEAN CRUISE A GREAT SUCCESS: The goals of the Shelf and Slope Experimental Taphonomy Initiative (SSETI) have been advanced by a very successful two-week collection trip to the Caribbean aboard the R/V EDWIN LINK and at the Caribbean Marine Research Center at Lee Stocking Island, Bahamas. We are looking at rates of deterioration of organism remains on the sea floor to better understand the fossilization process. In 1994 we deployed bivalves and snails in mesh bags as well as crabs, urchins, and 
various wood species. These deployments were made along a transect from 15 to 300 meters deep
facing into Exuma Sound (see map below). This summer we have made a 7-year collection using the
CLELIA submersible and have found that the condition of the shell material has
reached a critical state on the shallow shelf (15 & 30 meters), while samples in deep water
(200 - 300 meters) are nearly as pristine as the day they were deployed.
The image at right shows Strombus shells collected from 850 ft and from 50 ft to show the great difference in their rate of deterioration. The bag arrays become heavily encrusted down to 75 meters, but only small single-celled protists called foraminifera and the tubes of serpulid worms are common on the shells below one hundred meters. The experimental arrays are brought ashore and the shells, crabs, urchins and wood are examined by a team of researchers. The lab work consists of characterizing the ways the shells have changed over the 7 years that they have been sitting exposed on the sea floor. We quantify the amount of dissolution, fragmentation, and corrosion the shells have undergone as well as identifying and quantifying the species and area covered by encrusting and boring organisms. All these characteristics together form a "taphonomic signature" that is indicative of the environment in which the shells died. Paleontologists can use this kind of signature on fossils to reconstruct environments of the past. Personnel at Lee Stocking Island: Dr. Eric Powell, Rutgers University • SSETI founder Dr. Karla Parsons-Hubbard, Oberlin College • Encrusting organisms, esp. Bryozoa Dr. Sally Walker, University of Georgia • Encrusting organisms, esp. forams • Tethered shell experiments Dr. Carlton Brett, University of Cincinnati • Encrusting organisms Dr. George Staff, Austin Community College • Physical taphonomy Dr. Russell Callender, NOAA • Physical taphonomy Dr. Dennis Hubbard, Oberlin College • logistical assistance, videography Dr. Bill Kiene, Smithsonian Institution • Boring organisms Graduate students: Rich Krause, University of Cincinnati Emily Rose, University of Georgia Tom Jones, Texas A&M University Undergraduate student: Rebekah Shepard, Oberlin College Technicians: Kathy Alcox, Rutgers Allison Bonner, Rutgers  | |
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