首页> 中文期刊> 《地球环境学报》 >全新世大暖期时中国夏季风向西北大幅度漂移的一个古生物地层学证据

全新世大暖期时中国夏季风向西北大幅度漂移的一个古生物地层学证据

         

摘要

The lacustrine sediment contains a great amount of gasteropod fossils of the Holocene Megathermal (6~9 ka BP) of the Badanhaizi Lower Land located at southeastern margin of Badainjaran Desert, China. These areRadix cucunorica (Möellendorff),Succinea erythrophanaAncey,Gyraulus sibricus (Dunker),Radix lagotis (Schranck),Gyraulus albus(Müller),Lymnaea stagnalis(Linnaeus),Gyraulus convexiusculus (Hutton), in which, except terraneousSuccinea erythrophanaAncey, the rest belongs to freshwater gasteropods. They indicate then warm-humid climate, among which the existent northwesternmost of the extantGyraulus convexiusculus (Hutton) is of Nanniwan of Shanxi Province of Chinese warm temperate belt. Hence, it is assumed that during 6~9 ka B. P. the annual average temperature and precipitation of Badanhaizi probably were respectively 1.1℃ and 440 mm higher than those of the present-day; from Nanniwan to Badanhaizi, the climate belt almost migrated northwestward 700 km; the warm front of summer monsoon may moved to northwestward the range from Yumen to Ejin Qi in NE strike and further to the Sino-Mongolia boundary at that time, and its inlfuencing extension probably attained to Xingxingxia, the inner continent, of the boundary between Gansu and Xinjiang, China.%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(Möellendorff),Succinea erythrophanaAncey,Gyraulus sibricus (Dunker),Radix lagotis (Schranck),Gyraulus albus(Müller),Lymnaea stagnalis(Linnaeus), Gyraulus convexiusculus (Hutton),除Succinea erythrophanaAncey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。

著录项

相似文献

  • 中文文献
  • 外文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号