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Show We believe that the lake- level maxima ( 5180 minima), centered at 18 and 13.1 kyr, correspond to passages of the polar jet stream core over the Mono Basin. The 13.1 kyr sediment- based highstand occurs almost exactly at the same time as the wettest period documented in the Owens Lake record ( Fig. 2). The 5180 record from core PLC92B from the Pyramid Lake basin indicates the presence of a highstand lake at 13.3 kyr. As was the case in the Mono and Owens Lake systems, the last extreme wet event was preceded by a relative lowstand which in the Pyramid Lake basin occurred at 14.2 kyr during Heinrich event H1 ( Fig. 4a). In the Pyramid Lake basin, lowstands also occurred at about the same times as H2 and H3. In the tufa based lake- level chronology for Pyramid Lake ( Fig. 4b), the highstand lake appears to last from - 14.2 to - 12.8 kyr. This demonstrates . how the reservoir effect shifts carbonate 14C dates to larger values and the addition of modern carbon shifts carbonate 14C dates to smaller values. Core 0L84B obtained from the Owens basin in 1984 was used to determine the magnitude and timing of wet dry oscillations between 14.0 and 4.3 kyr. The 8180 data ( Fig. 5) indicate four extremely dry ( closed- basin) intervals ( D, through D4). The older three dry intervals are centered at 13.0, 11.3, and 10.5 kyr; the youngest dry interval ( D4) marked the beginning of the Holocene ( 9.8 kyr) and extends to Desiccation II. The presence of prismatic cracking ELEVATION ( m) 1150 1200 1250 1300 1350 | i i i i i i i r 33 32 31 30 29 28 27 26 25 24 23 8180(°/ oo) VSMOW Fig. 4. ( a) 8180 record from Pyramid Lake core PLC92B. H1- H3 refer to North Atlantic Heinrich events, ( b) tufa- based lake- level envelope for Lake Lahontan between 22 and 12 kyr. in the reddish D3 interval suggests the existence of a soil formed during subaerial exposure of lake sediments. Relatively wet intervals ( WT through W4) precede each of the desiccations. Interval \ N, was not recorded in the 5180 data set because the outflow: inflow ratio was too high to permit saturation with CaC03. Interval W2 contains two secondary peaks ( W2a and W2b). Comparison of the 5180 record of change in the hydrologic balance of Owens Lake with the GISP2 record of the Oldest Dryas/ B0lling/ OIder Dryas/ Aller0d/ Younger Dryas and Holocene cold/ warm oscillations indicates a remarkable degree of similarity in the number, duration, |