The Luocun Formation, a newly established Pleistocene stratigraphic unit in Qiongduojiang basin, southern Tibet
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摘要: 错那-沃卡裂谷是青藏高原南部的众多新生代南北向裂谷之一,该裂谷中段的邱多江盆地沉积了大面积的第四纪湖相沉积物。此前由于地质调查程度较低,古湖积物的地表调查工作基本属于空白。本次调查对洛村-邛多江盆地古湖积物进行了详细研究,在洛村地区发现了完整的古湖积物的连续沉积,测制了地层剖面,开展了精确的光释光定年分析,结果显示其沉积时代为上更新世。鉴于区域上该套更新世地层出露面积广、厚度大,故新建地层单元,定名为洛村组(Qp3lc);并推测邱多江-洛村古湖可能是雅鲁藏布江中部超大古堰塞湖的一部分,洛村组是由藏南地区错那-沃卡裂谷和古大湖共同作用形成,初步计算了古湖出水口、湖面高度、湖水面积等参数。Abstract: Though out detailed geological mapping, profiles' measuring, and optical stimulated luminescence dating, we named a new Pleistocene stratigraphic unit Formation, the Luocun Formation in the Qiongduojiang basin, southern Tibet. The Luocun Formation is mainly composed of lacustrine deposits such as clay, sand and gravel. It was a product of the paleo Yarlung Zangbo Jiang lake which was formed by the clogged Yarlung Zangbo River from 0.025Ma to 0.078Ma. During that time, the Luocun basin, in which the Luocun Formation occurred, was a part of the Yarlung Zangbo paleo-lake caused by activities of glacier and geological slides in the studied areas. Parameters such as its outlet, height, and lake surface of the Yarlung Zangbo paleo-lake are also preliminarily calculated in this paper.
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Key words:
- Luocun Formation /
- Qiongduojiang Basin /
- Pleistocene Intermediate /
- Paleolake sediments
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[1] Molnar P,Tapponnier P. Active tectonics of Tibet[J]. Journal of Geophysical Research, 1978, 83:5361~5375.
[2] Armijo R, Tapponier P, Mercier J L. Quaternary extension in southern Tibet:Field observations and tectonic implications[J].Journal of Geophysical Research, 1986, 91:13803~13872.
[3] 韩同林.西藏活动构造[M].北京:地质出版社, 1987.
[4] 李光明,张林奎,吴建阳,等.青藏高原南部洋板块地质重建及科学意义[J].沉积与特提斯地质,2020,40(1):1-14.
[5] 吴中海,张永双,胡道功,等.藏南错那-沃卡裂谷的第四纪正断层作用及其特征[J].地震地质,2008(01):144-160.
[6] 吴中海,张永双,胡道功,等.西藏错那-沃卡裂谷带中段邛多江地堑晚新生代正断层作用[J].地质力学学报,2007,(04):297-306.
[7] 吴中海,张永双,胡道功,等.西藏桑日县沃卡地堑的第四纪正断层活动及其机制探讨[J].地质学报,2007(10):1328-1337+1449-1450.
[8] 哈广浩,吴中海,何林.藏南邛多江地堑的晚新生代沉积地层及对南北向裂谷形成时代的初步限定[J].地质学报,2018,92(10):2051-2067.
[9] 王秋根,杨文光,朱利东,等.青藏邛多江盆地40.4~30.0 cal ka BP湖相沉积物粒度特征及其古气候意义[J].科学技术与工程,2018,18(04):1-7.
[10] 杨珍,杨文光,朱利东,等.青藏高原邛多江盆地湖相沉积物总有机碳含量及其碳同位素特征的古气候意义[J].矿物岩石,2017,37(02):102-110.
[11] 李杜文. 藏南邛多江盆地末次冰期以来的气候记录[D].成都:成都理工大学,2016.
[12] 中国地质调查局成都地质调查中心,四川省地质调查院. 西藏古木加康地区1:5万区域地质调查报告(H46E019009,H46E019010,H46E019011)[R].成都:四川省地质调查院,2019.
[13] 中国地质调查局成都地质调查中心、陕西省地质调查院. 西藏曲松地区1:5万区域地质调查(H46E018007、H46E018008、H46E018009、H46E018010)[R].成都:四川省地质调查院,2019.
[14] 中国人民武装警察部队黄金第十一支队. 西藏1:5万哲古、卡珠、邛多江、松多、卡果、让宗(H46E020007、H46E020008、H46E020009、H46E021007、H46E022007、H46E021008)幅区域地质矿产调查报告[R].2015.
[15] 西藏自治区地质调查院. 西藏1:5万H46E019007(琼果幅)、H46E019008(曲德贡幅)1:5万区域地质调查报告[R].拉萨:西藏自治区地质调查院,2012.
[16] 云南省地质调查院. 1:25万隆子县幅、扎日区幅地质调查报告(H46C004003、H46C004003)[R].昆明:云南省地区调查院,2005.
[17] 陈建军,季建清,龚俊峰,庆建春.雅鲁藏布江大峡谷的形成[J].地质通报,2008(04):491-499.
[18] Wang et al. (Reports, November.[Technical Comment] Comment on "Tectonic control of Yarlung Tsangpo Gorge revealed by a buried canyon in Southern Tibet"[J]. Science, 2015, 349(6250):799.
[19] 韩建恩, 孟庆伟, 郭长宝,等. 雅鲁藏布江中游杰德秀古湖的发现及其意义[J]. 现代地质, 2017(05):17-26.
[20] 刘宇平,Montgomery D R, Hallet B,等.西藏东南雅鲁藏布大峡谷入口处第四纪多次冰川阻江事件[J].第四纪研究,2006,26(1):52-62.
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