CAJ | 학술논문

塔西南坳陷位于西昆仑和南天山山前，早白垩世克孜勒苏群充填巨厚的粗碎屑沉积，是塔西南坳陷油气勘探的主要目标层段之一。通过大量的野外露头和盆内钻井对比，在克孜勒苏群内划分出3个三级层序，识别出冲积扇、辫状河、辫状河三角洲和曲流河-河流三角洲等沉积类型。重矿物物源体系分析表明，塔西南坳陷山前带和盆内钻井样品物质来源较复杂，既有岩浆成因，也有变质成因和再造沉积物，重矿物含量以赤铁矿、磁铁矿和白钛矿占绝对优势。重矿物组合类型反映出本区母岩性质主要为变质成因和岩浆成因，根据所处的地理位置进一步区分出南天山白垩纪高级变质岩母源区、西昆仑北带低级变质岩母源区和西昆仑南带基性火成岩3种不同的母源区。物源分析为沉积古地理恢复提供了重要依据，南天山西段山前以冲积扇-扇三角洲沉积为主，西昆仑北带早期以河流沉积为主，后期逐渐演化为冲积扇，西昆仑南带主要沉积河流-河流三角洲。扇/辫状河三角洲前缘水下分流河道、三角洲前缘水下分流河道和河口坝是形成优质储层的有利区。物源体系和沉积古地理分析对区内有利储集相带分布预测具有重要意义。
탑서남요함위우서곤륜화남천산산전，조백성세극자륵소군충전거후적조쇄설침적，시탑서남요함유기감탐적주요목표층단지일。통과대량적야외로두화분내찬정대비，재극자륵소군내화분출3개삼급층서，식별출충적선、변상하、변상하삼각주화곡류하-하류삼각주등침적류형。중광물물원체계분석표명，탑서남요함산전대화분내찬정양품물질래원교복잡，기유암장성인，야유변질성인화재조침적물，중광물함량이적철광、자철광화백태광점절대우세。중광물조합류형반영출본구모암성질주요위변질성인화암장성인，근거소처적지리위치진일보구분출남천산백성기고급변질암모원구、서곤륜북대저급변질암모원구화서곤륜남대기성화성암3충불동적모원구。물원분석위침적고지리회복제공료중요의거，남천산서단산전이충적선-선삼각주침적위주，서곤륜북대조기이하류침적위주，후기축점연화위충적선，서곤륜남대주요침적하류-하류삼각주。선/변상하삼각주전연수하분류하도、삼각주전연수하분류하도화하구패시형성우질저층적유리구。물원체계화침적고지리분석대구내유리저집상대분포예측구유중요의의。
Located between the west Kunlun Mountain and south Tianshan Mountain,there deposited huge thickness of coarse clastic Kezilesu Group in Lower Cretaceous southwest depression of Tarim Basin,which is one of the major reservoirs for oil/gas exploration.Based on lots of outcrops observation and well contrast,three 3 rd sequences have been classified,and sedimentary system have been recognized furthermore under the se-quence-stratigraphy framework,such as alluvial fan,braided river-braided delta and fluvial delta.Provenance analysis according to the heavy mineral of sandstone samples came from both outcrop and drill cores has revealed very complex source rock types,including magmatogenic,metamorphogenetic and recycled-orogenic source. Hematite,magnetite and leucoxene dominated.It's characteristic with high grade metamorphism in the south Tianshan Mountain,low grade metamorphism and basic igneous rock in north and south of the west Kunlun Mountain,respectively.Provenance analysis provided useful information for the paleogeography restore.There mainly deposited alluvial fan and fan delta along the south Tianshan Mountain,and fluvial dominated early in the north of the west Kunlun Mountain,and evolved an alluvial fan later,while fluvial and fluvial delta domina-ted the south of the west Kunlun Mountain.Fan-braided delta front distributary channel,delta front distributary channel and mouth bar sandstones are favor of good reservoir.Source system and paleogeography distribution have significance to favorable reservoir prediction.