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Numerous high amplitude oscillations exceeding the expected upper and lower limits
of 
18O lateral variability were detected in the 107.5 to 150
m core interval. These large oscillations may reflect increased seasonality
or better preservation of the annual signal as a result of the cooler temperatures
during the LIA. For example, the isotopically enriched horizons in this
interval could have resulted from decreased rates of melting of isotopically
enriched summer snowfall expected from cooler summer temperatures during
the LIA. During the 1990 and 1991 field seasons, summer snowfall at the
site melted within four days of deposition. The abrupt decrease in the
large amplitude oscillations at the 107.5 m depth suggests a sudden termination
of the LIA at this site.
