阿达滩盆地古近纪淡水腹足类化石的发现及其地质意义  

Discovery of freshwater Gastropoda fossils in Ancient Neoteric period and its geological significance in Adatan basin

作　　者：王进寿[1] 拜永山[1] 郝平[1] 常革红[1] 保光普[1] 

机构地区：[1]青海省地质调查院,青海西宁810012

出　　处：《西北地质》2004年第3期21-23,共3页Northwestern Geology

基　　金：中国地质调查局地质大调查项目(200113000058)

摘　　要：东昆仑西段阿达滩盆地早新生代陆相碎屑岩沉积建造,原先被笼统认为属"下第三系"。1∶25万库郎米其提幅区调中,在该碎屑岩建造中首次发现淡水腹足类化石:假菊石型南方圆螺黄河亚种AustralorbispseudoammoniushuanghoensisYu,实椎螺(未定种)Lymneasp.根据含化石地层的岩相特征及腹足类化石生存时代,阿达滩盆地的下第三纪应属古近纪渐新世的干柴沟组下部,据该套地层的存在及不整合覆盖于其上的早更新世七个泉组分析,推断阿达滩盆地在渐新世末存在一次较强规模的隆起。The triphibian chipping-rock sedimentary formation in Early Cenozoic in Adatan basin in western segment of east Kunlun Mt.was formerly considered to belong to 'Low Tertiary'.In the 1∶25 ten thousands Kelangmiqiti sheet of regional geology survey for the first time in the chipping-rock construct,the freshwater Gastropoda fossils were found: Australorbis pseudoammonius huanghoensis Yu, Lymnea sp.According to the stratum contained fossils lithofacies characteristics and the breatheable epoch of the Gastropoda fossils,someone considered that the 'Low Tertiary'in Adatan basin should belong to the Low Ganchaigou Group of Oligocene in Ancient Neoteric period.According to the analysis of the presence of that stratum and the Early Pleistocene Qigequan Formation unconformably covered,the once stronger scale apophysis was concluded in Adatan basin in Oligocene.

关 键 词：阿达滩盆地 古近纪 淡水腹足类 干柴沟组下部 高原隆升 

分 类 号：Q915.817[天文地球—古生物学与地层学]