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巴丹吉林沙漠东南部边缘巴丹海子全新世大暖期6~9 ka BP的湖相沉积中含有大量腹足类化石——Radix cucunorica(M(o|¨)ellendorff),Succinea erythrophana Ancey,Gyraulus sibricus(Dunker),Radix lagotis(Schranck),Gyraulus albus(M(u|¨)ller),Lymnaea stagnalis(Linnaeus),Gyraulus convexiusculus(Hutton),除Succinea erythrophana Ancey属陆生蜗牛外,余皆为淡水腹足类。这些化石代表了当时温暖湿润的气候环境。其中,现生的Gyraulus convexiusculus(Hutton)生活的最NW位置为地处暖温带的南泥湾,据此推知,6~9 ka BP时的巴丹海子的气温和降水至少较今分别高出1.1℃和440 mm;从南泥湾至巴丹海子,气候带向NW移动了差不多700 km;那时夏季风暖锋位置可向NW移动到从玉门其以NE走向至额济纳旗及其以北的中蒙国界一线,夏季风的波及范围可以漂越甘新交界的深居内陆的星星峡。
The lacustrine sediments of the Badanhaizi during the Holocene Megathernesis from 6 ka to 9 ka BP are rich in gastropods - Radix cucunorica (M (o | ¨) ellendorff), Succinea erythrophana Ancey, Gyraulus Gyrulus albus (Müller), Lymnaea stagnalis (Linnaeus), Gyraulus convexiusculus (Hutton), except Succinea erythrophana Ancey, are freshwater belly Foot class. These fossils represent the warm, humid climate of the time. Among them, the most NW location of the living Gyraulus convexiusculus (Hutton) is located in the warm temperate Nanniwan Bay. According to the deduction, the temperature and precipitation of Badanhazi at 6 ~ 9 ka BP are at least 1.1 ℃ and 440 mm respectively. From Nanniwan to Badanhaizi, the climate moved NW to almost 700 km. At that time, the warm front of the summer monsoon could move to the NW from Yumen to its Ejina Banner and its north Of the border between China and Mongolia, the reach of the summer monsoon can drifting beyond the Xingxingxia settlement in the hinterland of Gansu and New Zealand.