中国石油大学学报(自然科学版)
中國石油大學學報(自然科學版)
중국석유대학학보(자연과학판)
JOURNAL OF CHINA UNIVERSITY OF PETROLEUM(EDITION OF NATURAL SCIENCE)
2015年
1期
17-24
,共8页
张雷%李振海%张学娟%刘敏%申家年
張雷%李振海%張學娟%劉敏%申傢年
장뢰%리진해%장학연%류민%신가년
鄂尔多斯盆地%长7段%重力流沉积%岩相%岩相组合
鄂爾多斯盆地%長7段%重力流沉積%巖相%巖相組閤
악이다사분지%장7단%중력류침적%암상%암상조합
Ordos Basin%Chang 7 Member%gravity flows deposits%lithofacies%lithofacies association
在Tailling等分类的基础上建立基于沉积过程中的流变学特征和沉积物支撑机制的滑塌流-浊流-碎屑流三分(滑塌岩相、碎屑流岩相和浊积岩相)14个序列的重力流岩相划分体系;结合鄂尔多斯盆地合水地区长7段大量的岩心资料,并借助于测井曲线和录井数据,对合水地区长7段重力流沉积的岩相及岩相组合进行识别。结果表明:合水地区主要发育5类重力流沉积岩相组合类型,即低密度浊流组合、高密度浊流组合、黏滞性碎屑流组合、弱黏滞性碎屑流组合以及滑塌岩组合;对比合水地区重力流沉积空间发现,滑塌岩相发育范围相对局限,主要发育于三角洲前缘失稳区,碎屑流沉积主要发育于斜坡带-坡折带处,浊流沉积的分布范围最广;“浅水凸形”坡折带位于三角洲前缘或三角洲平原附近,是重力流重要的触发区,主要控制正常牵引流三角洲前缘中松散的水下分流河道砂体沉积;“深水凹形”坡折带位于前三角洲深水区,是深水重力流砂体主要的卸载沉积区。
在Tailling等分類的基礎上建立基于沉積過程中的流變學特徵和沉積物支撐機製的滑塌流-濁流-碎屑流三分(滑塌巖相、碎屑流巖相和濁積巖相)14箇序列的重力流巖相劃分體繫;結閤鄂爾多斯盆地閤水地區長7段大量的巖心資料,併藉助于測井麯線和錄井數據,對閤水地區長7段重力流沉積的巖相及巖相組閤進行識彆。結果錶明:閤水地區主要髮育5類重力流沉積巖相組閤類型,即低密度濁流組閤、高密度濁流組閤、黏滯性碎屑流組閤、弱黏滯性碎屑流組閤以及滑塌巖組閤;對比閤水地區重力流沉積空間髮現,滑塌巖相髮育範圍相對跼限,主要髮育于三角洲前緣失穩區,碎屑流沉積主要髮育于斜坡帶-坡摺帶處,濁流沉積的分佈範圍最廣;“淺水凸形”坡摺帶位于三角洲前緣或三角洲平原附近,是重力流重要的觸髮區,主要控製正常牽引流三角洲前緣中鬆散的水下分流河道砂體沉積;“深水凹形”坡摺帶位于前三角洲深水區,是深水重力流砂體主要的卸載沉積區。
재Tailling등분류적기출상건립기우침적과정중적류변학특정화침적물지탱궤제적활탑류-탁류-쇄설류삼분(활탑암상、쇄설류암상화탁적암상)14개서렬적중력류암상화분체계;결합악이다사분지합수지구장7단대량적암심자료,병차조우측정곡선화록정수거,대합수지구장7단중력류침적적암상급암상조합진행식별。결과표명:합수지구주요발육5류중력류침적암상조합류형,즉저밀도탁류조합、고밀도탁류조합、점체성쇄설류조합、약점체성쇄설류조합이급활탑암조합;대비합수지구중력류침적공간발현,활탑암상발육범위상대국한,주요발육우삼각주전연실은구,쇄설류침적주요발육우사파대-파절대처,탁류침적적분포범위최엄;“천수철형”파절대위우삼각주전연혹삼각주평원부근,시중력류중요적촉발구,주요공제정상견인류삼각주전연중송산적수하분류하도사체침적;“심수요형”파절대위우전삼각주심수구,시심수중력류사체주요적사재침적구。
Building upon prior investigations of Talling and others, a three-fold classification of gravity flow lithofacies was es-tablished based primarily on fluid rheological characteristics and sediment-support mechanisms of depositional processes. The new classification mainly contains slumps lithofacies, debris flow lithofacies and turbidite lithofacies, corresponding to the de-posits of slump, debris flow and turbidity current respectively, and can be further subdivided into 14 lithofacies. Using the a-bundant core data and logging data, lithofacies and lithofacies associations of gravity flows deposits were identified in Chang 7 Member of Heshui region, Ordos Basin. The results show that there are five types of lithofacies associations developed in Hes-hui region, including the low density turbidite association, the high density turbidite association, the viscous debris flow associ-ation, the weakly viscous debris flow association and the slumps association. The slumps lithofacies are located restrictively in the instable area of delta-front, the debris flow deposits are mainly developed in the slope to slope break zone, and the turbi-dites are on the other hand most widely distributed. The shallow water and convex slope break is located in the delta-front or the delta-plain, which is the initiating area of the gravity flow and mainly controls the distribution of loose sandy depositions of sub-sea distributary channels in delta-front caused by normal traction currents. The deep water and concave slope break is located in the deep water area of prodelta, which is the major unloading and deposition area of the gravity flows sand.