GSA Annual Meeting in Seattle, Washington, USA - 2017

Paper No. 302-12
Presentation Time: 11:00 AM


GEMERY, Laura, Eastern Geology and Paleoclimate Science Center, U.S. Geological Survey, 926A National Center, 12201 Sunrise Valley Drive, Reston, VA 20192,

The Arctic Ostracode Database (AOD) provides census data for 96 species of marine Ostracoda from 1340 modern surface sediments from the Arctic Ocean and subarctic seas. Ostracodes are meiofaunal Crustacea that secrete a bivalved calcareous (CaCO3) shell commonly preserved in sediments. Ostracode species have specific ecological limits controlled by temperature, salinity, oxygen, sea ice, food and other habitat-related factors. In addition to unique species ecology, their shell chemistry (Mg/Ca ratios, stable oxygen and carbon isotopes) and limited stratigraphic ranges make Ostracodaa useful tool for paleoceanography and biostratigraphy. Modern sediment samples in the AOD come from various sampling expeditions over the past few decades including Arctic abyssal plains, submarine ridges, continental slopes and shelves of the Kara, Laptev, East Siberian, Chukchi, Beaufort Seas and several subarctic regions such as the Bering Sea. An open-sourced file, the AOD includes latitude, longitude, water depth, bottom water temperature and collection year for most samples.

The AOD is used to investigate modern ostracode biogeography, regional community structure and ecology. In addition, fossil occurrences of a species with known modern environmental tolerances and ecology can provide a basis for the reconstruction of Cenozoic environments. Therefore, the AOD can provide a better understanding of how the Arctic Ocean has been affected by, and perhaps influence climatic and oceanographic change during both the Common Era and deeper geologic time (e.g. Quaternary and Pliocene).

This talk will address how the AOD can be used to address questions such as:

-- How is contemporary climate change affecting benthic ecosystems? Specifically, have ostracode assemblages changed over the last ~40 years?

-- What factors explain geographic differences in ostracode abundance and diversity?

-- Can the AOD be used to create temperature envelopes for modern Arctic and subarctic ostracode species environmental ranges and applied to fossil ostracode assemblages to approximate past ocean temperatures from the early Pliocene though the Pleistocene?