Deep-sea corals: A new ocean archive

Jess Adkins, Ph.D.
Lamont Doherty Earth Observatory
Columbia University

Friday, May 22, 1998
12:00 noon—Pacific Forum

Deep-sea corals are an extraordinary new archive of deep-ocean behavior. Through their relatively slow growth rates and intermediate- to abyssal-depth habitats, these species can record deep-ocean changes in chemistry and circulation at sub-decadal time scales. The species Desmophyllum cristagalli is a solitary coral composed of uranium rich, density-banded aragonite. Modern specimens collected from waters of known composition can be used to calibrate paleoceanographic tracers and study this species' growth rate and pattern. Using a newly developed ICP-MS age screening method, large numbers of fossil samples can be processed relatively quickly and inexpensively to uncover interesting corals for further analysis. Older specimens can constrain two important problems in current paleoclimate research: the deep ocean's behavior during rapid climate changes in the past glacial cycle, and the rate of deep-ocean circulation in the past.

I will present data on the rate of deep-circulation change during the beginning of the last deglaciation and discuss some possible uses of MBARI's submersible capabilities to study these animals in situ.

Next: Electromagnetic remote sensing of the Earth's plate boundaries