A 60 000-year loess-paleosol record of millennial-scale summer monsoon instability from Lanzhou, China  

作　　者：Yugo Ono Hitoshi Fukusawa Keiichi Oi 

机构地区：[1]Department of Geography , Tokyo Metropolitan University, Hachioji 192-03, Japan,Department of Geography , Tokyo Metropolitan University, Hachioji 192-03, Japan,Graduate School of Environmental Earth Science , Hokkaido University , Sapporo 060, Japan

出　　处：《Chinese Science Bulletin》1999年第24期2264-2267,共4页

摘　　要：The 28-m high-resolution Shajinping loess section in Lanzhou on the Chinese western Loess Plateau records a detailed history of millennial Asian summer monsoon change since the earlier last glaciation. Summer monsoon proxies of soil magnetic susceptibility, carbonate content and soil color show that Asian summer monsoon experienced a series of rapidThe 28-m high-resolution Shajinping loess section in Lanzhou on the Chinese western Loess Plateau records a detailed history of millennial Asian summer monsoon change since the earlier last glaciation. Summer monsoon proxies of soil magnetic susceptibility, carbonate content and soil color show that Asian summer monsoon experienced a series of rapid episodic pulse enhancements spanning only ca. 1–2 ka and have sub-Milankovitch cycles of progressive weakening in low frequency domain since ca. 60 kaBP. Soil formation responds to these by deepening colors, accumulating organic matter, increasing biological channels and leaching certain carbonates. The pedogenic degree generally increases with the degree of enhancement of summer monsoon. These may reflect the impact of the last glacial fast climatic change in the North Atlantic region on Asian summer monsoon.

关 键 词：last GLACIATION summer monsoon instability. 

分 类 号：P531[天文地球—古生物学与地层学]