柴达木盆地新近纪湖相风暴岩的发现及其对青藏高原隆升的地质意义  

THE DISCOVERY OF NEOGENE LACUSTRINE TEMPESTITES IN THE QAIDAM BASIN AND ITS GEOLOGICAL SIGNIFICANCE FOR THE UPLIFT OF THE QINGHAI-TIBET PLATEAU

作　　者：李磊[1] 李凤杰[1] 申玉山[2] 林洪[1] 杨豫川[1] 

机构地区：[1]成都理工大学沉积地质研究院,四川成都610059 [2]青海油田公司勘探开发研究院,甘肃敦煌736202

出　　处：《地层学杂志》2013年第1期48-53,共6页Journal of Stratigraphy

基　　金：国家自然科学基金(No.41172100);四川省教育厅重点项目(12ZA012)成果

摘　　要：通过对柴达木盆地路乐河和西岔沟剖面新近系沉积的详细分析,发现柴达木盆地新近纪发育典型的湖相风暴岩沉积。风暴沉积构造主要有风暴侵蚀构造、风暴撕裂构造、风暴浪构造以及及风暴期后快速沉积构造等,包括渠铸型构造、冲刷面构造、泥砾、丘状交错层理、洼状交错层理、平行层理和粒序层理等构造类型。根据风暴岩序列的规模、丘状交错层理的波长大小等因素分析柴达木盆地新近系上干柴沟组风暴的规模明显强于下油砂山组。上干柴沟组与下油砂山组之间古风暴强度的变化说明柴达木盆地在该时期发生了一次重大的古气候转型事件,与青藏高原整体初次隆升时间有较好的响应关系。风暴岩的发现,对于分析柴达木盆地新近纪的古地理、古气候、古构造及板块的运动规律具有重要意义,也为青藏高原的隆升研究提供了新资料、开辟了新途径。Neogene lacustrine tempestites have been found in a detailed study of the Lulehe and Xichagou sections in the Qaidam Basin. Evidence for storm sedimentation includes erosional structures, tear-structures, storm-surge structures, storm eddy structures, rapid post-storm deposition, channel structures, scouring structures, mud pebbles, hummocky cross bedding, swaley cross bedding, parallel bedding, and graded bedding. Based on the analysis of the wavelength hummocky cross tempestites in the Neogene Shangganchaigou Formation is larger than those in tion. This change implies a climate event in the Qaidam Basin in the Neogene, bedding, the magnitude of the Xiayoushashan Formaand may represent a paleoclimatic response to the early uplift of the Qinghai-Tibet Plateau. The new findings have significance in the interpretation of Neogene palaeogeography, palaeoclimate, and palaeotectonics of the Qaidam Basin. The data presented here can also provide new insights into the uplift of the the Qinghai-Tibet Plateau.

关 键 词：事件地层 古地理 风暴岩 隆升 新近纪 青藏高原 柴达木盆地 青海 

分 类 号：P534.62[天文地球—古生物学与地层学]