Sedimentary Evolution of the Upper Triassic Jiapila Formation at the oft-com:office:smarttags" />Middle Qiangtang Basin and its Geological Significance

详细信息   

• 责任者：Tang Zhaoyang (Wuhan Institute of Geology and Mineral Resources ; Wuhan 430223 ; China) ; Wu Jianhui
• 刊名：Geotectonica et Metallogenia
• 出版年：2011
• 卷期：35(3)
• 关键词：沉积演化 ; sedimentary evolution ; 晚三叠世 ; Upper Triassic ; 羌塘盆地 ; Qiangtang Basin
• 页码：p.421-428
• 图表：3 illus., 1 table, 14 refs.
• 分类号：0803
• 出版序号：310
• issnNo：ISSN1001-1552
• isbnNo：CN44-1595/P

摘要

 Based on the facies marks including sediment-style and assemblages(lithology,color,strata type,grain type),vertical depositional features,fabric and construct characters,and biotic assemblages as well as authigenic mineral and geochemical characteristics,9 types of sedimentary facies in the Jiapila Formation within Yangtze source region can be recognized:pluvial facies,fluvial facies,detal facies,tidal flat facies,subtidal facies of restricted platform,longshore bar facies and volcanic eruption facies,as well as platform marginal facies.The bivalves fossil of Quemocuomegalodon sp.and Neomegalodon cf.ampezzanus(Hoernes) as well as gypsum deposit were discovered in the restricted platform.Moreover,barite,fluorite and other minerals were found in the gypsum deposition;therefore,all of these suggest that the deposit of lazurite,barite and fluorite are the prospecting potential in the restricted platform facies.The biologic features and sedimentary characteristics of the Jiapila Formation suggest that it was sedimented in shallow-water environment with high rate of evaporation.The new data on the sedimentary facies of the formations provide important information to understand the regional tectonic-paleogeographic environment during the Indosinian movement.