CAJ | 학술논문

青海聚乎更矿区是全球陆域中纬度地区天然气水合物的首要发现地，水合物储存层位主要为该矿区三露天井田的中侏罗世含煤岩系。依据钻孔岩心及测井曲线，对该矿区三露天井田含煤岩系进行沉积环境分析，在单孔沉积相及沉积相断面图分析的基础上，重建研究区的岩相古地理格局。木里组下段岩性主要为细砾岩、含砾粗砂岩及粗砂岩等粗粒岩石，以辫状河为主的沉积环境；木里组上段岩性以厚层砂岩与厚层煤层互层为特征，反映了水体逐渐加深的过程中发育三角洲为主的沉积环境；江仓组下段以细粒砂岩及泥岩互层夹薄煤层为特征，反映水体进一步加深过程中的三角洲前缘和滨浅湖环境；江仓组上段以油页岩、暗色泥岩为主，含有瓣鳃类化石，反映湖泊为主的沉积环境。
청해취호경광구시전구륙역중위도지구천연기수합물적수요발현지，수합물저존층위주요위해광구삼로천정전적중주라세함매암계。의거찬공암심급측정곡선，대해광구삼로천정전함매암계진행침적배경분석，재단공침적상급침적상단면도분석적기출상，중건연구구적암상고지리격국。목리조하단암성주요위세력암、함력조사암급조사암등조립암석，이변상하위주적침적배경；목리조상단암성이후층사암여후층매층호층위특정，반영료수체축점가심적과정중발육삼각주위주적침적배경；강창조하단이세립사암급니암호층협박매층위특정，반영수체진일보가심과정중적삼각주전연화빈천호배경；강창조상단이유혈암、암색니암위주，함유판새류화석，반영호박위주적침적배경。
The Juhugeng mining area in Qinghai Province is the primary discovery site of the gas hydrates in the mid-latitude of the global land,with the gas hydrates being preserved in the Middle Jurassic coal-bearing series of the Sanlutian mining field.This paper analyzed the depositional environments of the coal-bearing series in the Sanlutian mining field by using the borehole cores and logging curves.The palaeogeographic outlines of each lithological member of the Middle Jurassic have been reconstructed based on the single borehole facies analysis and the cross-section facies correlations.The lithology of the Lower Member of the Muli Formation is mainly fine conglomerates,pebbly sandstone and coarse-grained sandstone,reflecting a braided river-dominated environ-ment.The Upper Member of the Muli Formation is characterized by the thick sandstone interbedded with thick coal seam,indicating a gradual deepening process and development of the deltaic environment.The Lower Member of the Jiangcang Formation is characterized by the fine-grained sandstones interbedded with mudstones and thin coal seams,signifying a further deepening process and development of the delta front and shore-shallow lake environments.The Upper Member of the Jiangcang Formation consists mainly of oil shale and dark mud-stone containing bivalve fossils,reflecting a shallow to deep lake environment.