Lake Hovsgol Magnetoclimate Record During the Past 20,000 Years

Lake Hovsgol is 135 km long, average 20 km wide, and is situated at the altitude of 1645 m above sea level in northern Mongolia where East Asian Winter Monsoon dominantly affects the climate. We have conducted various magnetic measurements for five gravity cores obtained from the bottom of Lake Hovsgol. Our data show that the magnetic granulometry inferred from ARM/SIRM and ARM/χ reflects well paleoclimatic change in the study area rather than the magnetic concentration and the magnetic composition. Rock magnetic results indicate that the characteristic remanence is carried mainly by detrital magnetite. It is worth noting that the magnetic composition parameters such as Hcr and S-ratio vary within a narrow range and show a trend similar to that of the magnetic granulometry parameters, indicating that variations of Hcr and S-ratio are influenced by magnetic domain size in this case. The Younger Dryers and the Holocene cooling events (i.e. Bond events) were recognized by negative peaks in the down core variation curves of the magnetic granulometry parameters, suggesting that the magnetic grain size increases as the temperature decreases in the study area.