A laminated carbonate record of mid-continental climate during the late Glacial and Holocene from Martin Lake, northeastern Indiana: Initial sedimentological and chronological results
Abstract
Paleoclimate records from the mid-continental United States that span the late Glacial and Holocene with sub-decadal resolution are rare. This is especially true for geochemical records that capture the isotopic composition of precipitation or local precipitation/evaporation balances. As a result, many questions remain about the hydrologic expression of abrupt climate events in this region that today is one of the largest agricultural centers in the world. Here, we present preliminary limnological, sedimentological and chronologic data from a set of new sediment cores from Martin Lake in northeastern Indiana. Today, this kettle lake is hydrologically open with persistent water column stratification and bottom water anoxia. Imaging of the ~8 m composite sediment archive shows that mm-scale couplets composed of alternating layers of organic matter and carbonate minerals are present throughout the core. Ongoing radiometric dating of the cores will be used to determine the depositional significance of the couplets and their potential for additional chronologic constraint. Initial basal age estimates, however, suggest that the composite record may extend back as far as 19,000 cal yr B.P. The Martin Lake record therefore holds great potential for providing a carbonate d18O record of late Glacial and Holocene climate events at sub-decadal resolution.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2013
- Bibcode:
- 2013AGUFMPP33A1908S
- Keywords:
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- 4942 PALEOCEANOGRAPHY Limnology;
- 1605 GLOBAL CHANGE Abrupt/rapid climate change;
- 9350 GEOGRAPHIC LOCATION North America;
- 1051 GEOCHEMISTRY Sedimentary geochemistry