2001-2002 Funded CGRER Seed Grants

High Resolution Stable Isotope Analysis of the Last Deglaciation as found in the Sediments of Glovers Pond, New Jersey
Scott Carpenter, Geoscience, UI

While well documented in Europe, lacustrine sediments from North America have yielded few oxygen isotope data sets that can be correlated with the climate changes observed in Greenland ice cores (DYE 3, GRIP, and GISP 2). In part, this paucity of data sets stems from the relatively young age and relatively large size of the lakes chosen for study. Glovers Pond, a small lake in NW New Jersey is the appropriate size and age to record these climate changes. Preliminary radiocarbon dating and stable isotope analyses from sediment cores sampled at low temporal resolution indicates that all of the major climate changes of the last 20,000 years are recorded in the d18O values of sedimentary carbonate (Oldest Dryas through Holocene) and thus, this site contains a unique record of the last deglaciation. The d18O value variation is comparable to that in Greenland ice cores and to analogous lakes in Switzerland and France.

In July 2000, several cores were collected from Glovers Pond and subsequently sampled at 1-cm intervals for high-resolution stable isotope analyses (carbonate and organic matter). Funding is requested to defray the costs of high-resolution stable isotope analyses and for a preliminary calibration of 14C ages using U-series dating. The proposed research will yield a complete, high-resolution record of the last deglaciation for northeastern North America. Proximity of Glovers Pond to the North Atlantic (an important area for controlling ocean circulation and perhaps climate) makes these data and ages valuable for understanding the relation between ocean circulation and continental climate change.more