Tectonic evolution and accumulation characteristics of Carboniferous shale gas in Yadu-Ziyun-Luodian aulacogen, Guizhou Province, South China  

作　　者：Kun Yuan Wen-hui Huang Ting Wang Shi-zhen Li Xiang-can Sun Xin-xin Fang Jun-ping Xiao Jun Guo 

机构地区：[1]Oil and Gas Resources Survey,China Geological Survey,Ministry of Natural Resources,Beijing 100083,China [2]China University of Geosciences(Beijing),Beijing 100083,China [3]The key Laboratory of Unconventional Oil and Gas Geology,China Geological Survey,Beijing 100083,China [4]Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China [5]No.814 Geological Party,East China Bureau of Mineral Exploration and Development,Zhenjiang 212005,China [6]Hunan Institute of Geophysics and Geochemistry,Changsha 410000,China

出　　处：《China Geology》2023年第4期646-659,共14页中国地质（英文）

基　　金：supported by the China Geological Survey Projects of Shale Gas Survey in the GuizhongNanpanjiang Area (DD20190088);Investigation and evaluation of Paleozoic shale gas in Yunnan-Guizhou-Guangxi region (DD20230264);Investigation and Evaluation of Carboniferous Shale Gas in Southern Guizhou-Central Guangxi (ZDDYR2023018);Reservoir Characteristics and Gas Accumulation of Trough-platform Shale: A Case Study of Early Carboniferous Shale in Yaziluo Rift Trough (YKC2023-YC08)。

摘　　要：The Yadu-Ziyun-Luodian aulacogen(YZLA) developed into being NW-trending in the Late Paleozoic,and was considered as an important passive continental margin aulacogen in Guizhou Province, South China. This tectonic zone is considered a large intracontinental thrust-slip tectonic unit, which has undergone a long period of development. It was ultimately determined in the Yanshanian, where the typical Upper Paleozoic marine shales were deposited. In 2021, Well QSD-1 was deployed in the Liupanshui area at the northwest margin of the aulacogen, and obtained a daily shale gas flow of 11011 m3in the Carboniferous Dawuba Formation. It thus achieved a breakthrough in the invesgation of shale gas in the Lower Carboniferous in South China, revealing relatively good gas-bearing properties and broad exploration prospects of the aulacogen. Being different from the Lower Paleozoic strata in the Sichuan Basin and the Yichang area of the Middle Yangtze, the development of the Carboniferous Dawuba Formation in the aulacogen exhibits the following characteristics:(1) The Lower Carboniferous shale is thick and widely distributed, with interbedded shale and marlstone of virous thickness;(2) The total organic carbon(TOC) content of the shale in the Dawuba Formation ranges from 1% to 5%, with an average of 2%, and the thermal maturity of organic matter(Ro) varies from 1% to 4%, with an average of2.5%, indicating good hydrocarbon generation capacity;(3) The main shale in the aulacogen was formed during the fault subsidence stage from the Middle Devonian to the Early Permian. Although the strong compression and deformation during the late Indosinian-Himalayan played a certain role in destroying the formed shale gas reservoirs, comparative analysis suggests that the area covered by the current Triassic strata has a low degree of destruction. It therefore provides good conditions for shale gas preservation,which can be regarded as a favorable area for the next exploration.

关 键 词：Shale gas AULACOGEN CARBONIFEROUS Shale and marlstone Organic carbon Organic matter Hydrocarbon generation capacity Tectonic evolution Accumulation characteristics 

分 类 号：P61[天文地球—矿床学]