Journal of Paleolimnology

, Volume 17, Issue 1, pp 85–100

Holocene climate reconstructions from tandem trace-element and stable-isotope composition of ostracodes from Coldwater Lake, North Dakota, U.S.A.

  • J. Xia
  • B. J. Haskell
  • D. R. Engstrom
  • E. Ito
Article

DOI: 10.1023/A:1007921328712

Cite this article as:
Xia, J., Haskell, B.J., Engstrom, D.R. et al. Journal of Paleolimnology (1997) 17: 85. doi:10.1023/A:1007921328712
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Abstract

The geochemistry of ostracode shells and bulk carbonates in a 19-meter sediment core documents at century-scale resolution the evolution of water chemistry in Coldwater Lake, North Dakota, providing a continuous paleohydrologic record of Holocene climate change in the northern Great Plains. A combination of δ18O, δ13C, Mg/Ca and Sr/Ca in ostracode calcite aided by Sr/Ca in bulk carbonates are used to constrain the paleoclimatic reconstructions. A fresh-water phase in the early Holocene, indicated by the absence of Candona rawsoni and low concentrations of Sr/Ca in bulk carbonate, was followed by a sharp increase in salinity between 10 800 and 8900 yr B.P. The climate was predominately dry during the late part of the early Holocene and most of the middle Holocene (8900–5000 yr B.P.), when the lake was very sensitive and recorded a series of dry and wet oscillations. Maximum salinity occurred around 5500 yr B.P. and was followed by a gradual decrease between 5000 and 2400 yr B.P. From 2400 yr B.P. the δ18O, Mg/Ca, and Sr/Ca in the ostracodes indicate generally wet conditions interrupted by a series of lesser salinity and temperature oscillations lasting until 600 yr B.P. Ostracode geochemistry indicates that a warm and dry climate returned at about the time of the Little Ice Age (600–150 yr B.P.). Ostracode δ13C shows a ong-term increasing trend during the Holocene, which suggests that lake productivity and atmospheric CO2 exchange made greater contributions to the hypolimnetic carbon pool as the lake became shallower with time.

Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • J. Xia
    • 1
  • B. J. Haskell
    • 1
  • D. R. Engstrom
    • 1
  • E. Ito
    • 1
  1. 1.Limnological Research Center, Department of Geology & GeophysicsUniversity of MinnesotaMinneapolisUSA
  2. 2.St. Croix Watershed Research StationScience Museum of MinnesotaSt. CroixUSA