Lake sediments as continental d18O records from the glacial/post-glacial transition.

Abstract

As in polar ice, 18O variations of precipitation are recorded in carbonate sediments formed in lakes (lake marl). We have analyzed many late-glacial profiles from Europe. There are strong 18O variations which coincide with well-known pollen zone boundaries and which indicate that abrupt, drastic climatic changes occurred in the late glacial period. Comparison of the d18O records of European lake sediments and of Greenland ice cores reveal a striking similarity which indicates that climatic changes in the late glacial and early postglacial were parallel in Greenland and in Europe. First results from North American lake-sediment profiles do not exhibit similar d18O variations. -from Authors