塔里木盆地北缘奥陶系古溶洞和古岩溶沉积中包壳砾石和包壳砾岩的发现及特征  

Discovery and characteristics of coated gravels and coated conglomerates from the Ordovician karst cave and sediment in northern margin of Tarim Basin

作　　者：钟建华[1] 倪良田[1] 曹梦春 陈鑫 张丹锋[3] 孙宁亮 郝兵 刘闯 邵珠福[4] 牛永斌[5] Zhong Jianhua Ni Liangtian Cao Mengchun Chen Xin Zhang Danfeng Sun Ningliang Hao Bing Liu Chuang Shao Zhufu Niu Yongbin(School of Geosciences, China University of Petroleum （ East China ） , Qingdao 266580, Shandong BGP Geophysical Research Institute, CNPC, Zhuozhou 072751, Hebei Research Institute of Petroleum Exploration ＆ Development, PetroChina, Beijing 100083 Qingdao Institute of Marine Geology, China Geological Survey, Qingdao 266071, Shandong Institute of Resources and Environment, Henan Polytechnic University, Jiaozuo 454000, Henan)

机构地区：[1]中国石油大学(华东)地球科学与技术学院,山东青岛266580 [2]中国石油东方物探公司研究院,河北涿州072751 [3]中国石油勘探开发研究院,北京100083 [4]中国地质调查局青岛海洋地质研究所,山东青岛266071 [5]河南理工大学资源环境学院,河南焦作454000

出　　处：《古地理学报》2016年第5期721-730,共10页Journal of Palaeogeography：Chinese Edition

基　　金：国家自然科学基金项目(批准号:41172093);国家重大基础研究规划项目(编号:2006CB202401);国家油气重大专项(编号:2008ZX05014-002-002HZ)共同资助~~

摘　　要：塔里木盆地北缘奥陶系发育典型的古岩溶,笔者在其中发现了一种非常特殊的沉积物或沉积构造:包壳砾石和包壳砾岩,且这种包壳砾岩之前从未见报道。该包壳砾石和包壳砾岩的结构类似鲕粒或核形石,可分为核心和包壳2部分,大部分呈近圆形或扁圆形,少数形态不规则,直径为数厘米到数十厘米。核心可分为4种,分别是:(1)与溶洞围岩相同的灰岩砾石;(2)由砂岩形成的核心;(3)由砾岩构成的复合核心;(4)由古钙华碎块形成的核心。包壳也可分为4种类型,分别是:(1)具有圈层的包壳;(2)颗粒状包壳;(3)均质包壳;(4)由颗粒状包壳和圈层状包壳组合形成的复合包壳。包壳砾石和包壳砾岩是溶洞和岩溶沉积中的典型产物,其不仅可以作为识别溶洞和岩溶的标志之一,而且具有一定的储集能力,是一种有效的油气储集体。Coated gravels and coated conglomerates,a specific type of sediment from karst caves and palaeokarsts,were found in the Ordovician in northern margin of Tarim Basin. These coated gravels and coated conglomerates,not been documented previously,are characterized by oolith-or oncolite-like textures,i.e.,a core and coat around the core. The core is divided into four types：（ 1） limestone gravel identical to the country rock of the karst cave;（ 2） core composed of sandstone;（ 3） composite core of conglomerates and（ 4） core comprised by palaeotravertine clasts. The coat is also divided into four types：（ 1） coat with cycles;（ 2） granular coat;（ 3） homogeneous coat and（ 4） composite coat comprised by granular coats and cycle-like coats. Coated gravels and coated conglomerates are typical products of karst caves and palaeokarsts,which can be served as markers of the presence of karsts and karst caves.Furthermore,the inherent storage capability in coated gravels and coated conglomerates make them effective hydrocarbon reservoirs,and thus a target for oil and gas exploration and development.

关 键 词：包壳砾石 包壳砾岩 溶洞 岩溶 奥陶系 塔里木盆地 

分 类 号：P588.245[天文地球—岩石学]