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西藏那曲县西的错鄂(31°24′～31°32′N,91°28′～91°33′E,湖面海拔4515m)东南岸(嘎杂西北坡),发育了拔湖18～271m的湖相沉积。错鄂及邻区湖相沉积的U系法测年和孢粉分析结果表明,至少在75.3～48.8kaBP间,当地植被经历了早期以松、蒿、桦为主的森林草原和晚期以松、蒿、水龙骨科为主的森林草原或森林等两个阶段,反映了气候由温和较干到温和偏干的状况,但晚期温度与湿度均较早期为高,而干燥度则略有降低。同时,包括错鄂盆地在内的“那曲盆地”则是古“羌塘东湖”的东半部。约在37kaBP左右,可能由于怒江的溯源侵蚀,切开了“羌塘东湖”与怒江的分水岭,使“羌塘东湖”的东半部古湖外泄,而成为外流区———怒江(上游那曲)流域的一部分。正因为有古湖外泄的一段历史,故可以理解钻穿了整个第四纪地层的错鄂孔B/M界线以上部分的地层较薄的原因了。
On the southeastern coast of the fault zone (31 ° 24’-31 ° 32’N, 91 ° 28’-91 ° 33’E, 4515m above sea level) in the west of Naqu County in Tibet, 18 ~ 271m Lacustrine deposits. The results of U-dating and pollen analysis of lacustrine sediments in the fault zone and its adjacent areas show that, at least between 75.3 and 48.8 kaBP, the native vegetation experienced the early steppe and the steppe mainly in the pine, Artemisia, water keel-based forest steppe or forest in two stages, reflecting the climate from mild to moderate dry to dry conditions, but the late temperature and humidity were higher than the early, while the dry slightly lower. At the same time, the “Nagqu Basin” including the Er’ao Basin is the eastern half of the ancient “East Lake of Qiangtang.” About 37kaBP, due to the trace erosion of the Nu River, the watershed between “the East Lake of Qiangtang” and the Nu River was cut off to make the eastern half of the “Qiangtang East Lake” leak and become the outflow area --- Nujiang River Nagqu) part of the basin. Because of the history of the ancient lake leakage, it is possible to understand the reason that the strata drilled through the B / M boundary of the Er’kou hole in the entire Quaternary strata are thin.