Contribution of aeolian dust in Japan Sea sediments estimated from ESR signal intensity and crystallinity of quartz

Abstract

Late Quaternary hemipelagic sediments in the Japan Sea contain aeolian dust from East Asia which potentially records past variations in the Asian monsoon and the westerly jet. However, extracting information about aeolian dust from Japan Sea sediments is difficult because the sediments also contain detrital material from the Japanese Islands. Here we present a method for extracting the aeolian dust components from Japan Sea hemipelagic sediments using provenance analysis of different size fractions. Hemipelagic sediments of the Japan Sea can be described by a combination of two populations characterized by lognormal grain size distributions with different median grain sizes, which are called the coarser (2-15 mm) and the finer (<10 mm) populations. We characterized these populations on the basis of provenance analyses, using the electron spin resonance (ESR) signal intensity and crystallinity of quartz. The results suggest that quartz in the coarser population has been mostly supplied from Northern China and Siberia/northeastern China by aeolian transport, whereas quartz in the finer population has been dominantly supplied by rivers draining the Japanese Islands. Copyright 2007 by the American Geophysical Union.