Rt. Klein et al., ELEMENTAL AND ISOTOPIC PROXIES OF PALEOTEMPERATURE AND PALEOSALINITY - CLIMATE RECONSTRUCTION OF THE MARGINAL NORTHEAST PACIFIC CA 80 KA, Geology, 25(4), 1997, pp. 363-366
Isotope (delta(18)O) and minor element (Mi/Ca, Sr/Ca) analyses of a fo
ssil shell of the marine mussel Mytilus trossulus (Could) from the Whi
sky Run terrace at Coquille Point, Bandon, Oregon, enable reconstructi
on of a paleoclimatic profile for the temperate northeastern Pacific c
a. 80-85 ka. The Whisky Run terrace is correlative with marine oxygen
isotope (delta(18)O) substage 5a, the final sea-level highstand of the
last interglacial complex. Herein we provide sea-surface temperature
estimates and report on a new technique that allows estimates to be ma
de of delta(18)O of seawater and riverine discharge from the skeletal
chemistry of a single mussel shell. Estimates of mean annual temperatu
re from Mg/Ca ratios are lower than those suggested by the accompanyin
g fossil fauna, and significantly lower than present-day conditions. T
he data also suggest a decrease in the range of seasonal temperature e
xtremes at 80 ka compared to today. Estimates of the fresh-water and s
eawater delta(18)O end members, -4.5 parts per thousand and +0.5 parts
per thousand, respectively, are slightly greater than modern values.