CAJ | 학술논문

新疆三塘湖盆地晚古生代发育哈尔加乌组和卡拉岗组陆相火山喷发岩系,二者在岩石组合上均以中酸性火山岩及其碎屑岩为主,局部夹基性火山岩.通过岩性剖面和化石组合对比认为哈尔加乌组和卡拉岗组为同一时代地层,没有上下关系,时代为晚石炭世一早二叠世.对哈尔加鸟组火山岩进行锆石SHRIMP U-Ph定年获取年龄值为319.6±9.8 Ma,表明这套火山岩含有石炭纪的部分,限定这套火山岩系的喷发时限为石炭纪中期至早二叠世.哈尔加乌组和卡拉岗组火山岩发育多期的火山喷发一沉积旋回,形成巨厚层的火山岩和火山碎屑岩的互层,具备良好的油气储集条件,其下伏老爷庙组暗色泥岩夹层有机碳(TOC)含量较高(0.71%～1.62%),属于一般烃源岩-好烃源岩,这套烃源岩与哈尔加乌组-卡拉岗组火山岩构成生储盖组合,上覆上二叠统芨芨槽子群泥岩为盖层,构成盆地与火山岩相关的石炭系含油气系统,具有重大的石油地质意义.
신강삼당호분지만고생대발육합이가오조화잡랍강조륙상화산분발암계,이자재암석조합상균이중산성화산암급기쇄설암위주,국부협기성화산암.통과암성부면화화석조합대비인위합이가오조화잡랍강조위동일시대지층,몰유상하관계,시대위만석탄세일조이첩세.대합이가조조화산암진행고석SHRIMP U-Ph정년획취년령치위319.6±9.8 Ma,표명저투화산암함유석탄기적부분,한정저투화산암계적분발시한위석탄기중기지조이첩세.합이가오조화잡랍강조화산암발육다기적화산분발일침적선회,형성거후층적화산암화화산쇄설암적호층,구비량호적유기저집조건,기하복로야묘조암색니암협층유궤탄(TOC)함량교고(0.71%～1.62%),속우일반경원암-호경원암,저투경원암여합이가오조-잡랍강조화산암구성생저개조합,상복상이첩통급급조자군니암위개층,구성분지여화산암상관적석탄계함유기계통,구유중대적석유지질의의.
Haerjiawu Formation and Kalagang Formation are continental volcanic rock series and widely developed in Santanghu Basin,Xingjiang.Both Haerjiawu Formation and Kalagang Formation are dominated by intermediate-acid volcanic rocks and pyroclastic rocks with local basic volcanic rocks.A comparative study on the rock association and fossil assemblage of Haerjiawu Formation and Kalagang Formation shows that two formations are similar at the forming age of late Carboniferous to early Permian.The Zircon SHRIMP U-Pb dating of volcanic rocks in Haerjiawu Formation is 319.6±9.8 Ma.Therefore.the volcanic rocks are confined to develop from middle Carboniferous to early Permian.Haerjiawu Formation and Kalagang Formation developed multistage volcanic-sedimentary cycles and contain massive volcanic rocks interbedded with pyroclastic rocks,which provides good reservoirs.Dark mudstone in underlying Laoyemiao Formation shows good organic matter with TOC(Total organic carbon)ranges of 0.71%～1.62%,which is believed to be good hydrocarbon source rock.Hydrocarbon source rock in Laoyemiao Formation,volcanic rocks in Haerjiawu Formation and Kalagang Formation and mudstone in Upper Permian Jijicaozi Group as a source-reservoircap combination constitute Carboniferous petroleum system and are significant for petroleum exploration.