A Preliminary Orbit-Tuned Time Scale for Thick Loess Deposit at Xining， the North Eastern Qinghai-Tibetan Plateau

• 责任者：Hu Ting (School of Geographic and Oceanographic Sciences ; Institute for Climate and Global Change Research ; Nanjing University ; Nanjing 210093 ; China) ; Lu Huayu
• 刊名：Quaternary Sciences
• 出版年：2010
• 卷期：30(1)
• 关键词：黄土 ; loess ; 地质年代学 ; geochronology ; 青藏高原 ; Qinghai-Tibetan Plateau
• 页码：p.62-68
• 图表：3 illus., 1 table, 34 refs.
• 分类号：1300
• issnNo：ISSN1001-7410
• isbnNo：CN11-2708/P

The authors undertook a drill project at the site with the thickest loess deposit in the North Eastern Qinghai-Tibetan Plateau. The Panzishan core (181.7 m) was sampled every 5 cm，all samples were measured for grain size distribution. In this paper，paleomagnetic ages are chosen as independent control points , the ETP curve is selected as target and the APC automatically orbital tuning method is used. A preliminary orbit-tuned time scale for Xining thick loess has been developed based on comparison between the mean grain size variations and the insolation of 65°N since the Early Pleistocene. After tuning，the new time scale is tested by cross spectral analysis. The results show that either the grain size record or the ETP curve has changed at a lager amplitude and higher frequency in orbital periods. In addition，the grain size record and ETP curve are highly correlated in the orbital periods.