【作者】 陈鑫；

【导师】 钟建华；

【作者基本信息】 中国石油大学 ， 地质学， 2010， 博士

【摘要】 随着塔里木盆地勘探和开发的不断加深,缝洞型碳酸盐岩储集体逐渐成为塔河油田的研究热点,此类储集体多产于奥陶系碳酸盐岩中,具有地层老、埋藏深、非均质性强和溶洞内充填物复杂的特点,严重的制约了油田的勘探开发。本论文围绕缝洞型碳酸盐岩储集体特征这一主题,综合利用野外露头、岩心、测井、地球物理和多种分析测试等资料,运用塔河油田地下储层和巴楚地区野外露头对比研究的方法,对缝洞型碳酸盐岩储集体进行了系统的研究。对塔里木盆地的塔河油田地下奥陶系缝洞型碳酸盐岩储层的研究,认为塔河油田在奥陶系发育碳酸盐岩台地相,储层主要由颗粒灰岩、微晶灰岩、白云石砂屑斑状灰岩、藻(礁)灰岩、白云岩、岩溶岩等六类岩石组成。成岩作用现象复杂多样,早期弱胶结作用、晚期压实压溶作用及相关的缝合线的形成、溶解作用及岩溶作用、表生期的混合白云化作用、破裂作用和多期裂缝的形成都有利于形成物性较好的储层。成岩演化特征复杂,主要经历了海底成岩环境、地表大气淡水成岩环境和深埋藏成岩环境。储集空间类型主要为大型洞穴、溶蚀孔洞和裂缝三种类型。储层可以分为溶洞型、裂缝—孔洞型和裂缝型3种储集体类型,其中,大溶洞型储集体是研究区最重要的一种储层。储层在垂向上,可以按洞穴层顶距T74面距离0-60m、60-150m和大于150m分为3个带,在平面上,可以按距T74面距离60m处分为两层。塔河油田缝洞型储集体受岩溶古地貌和古水系控制,在岩溶台地带和大型断裂、裂缝带以及多组断裂的交汇处溶洞更加发育。对塔里木盆地巴楚野外露头奥陶系缝洞型碳酸盐岩储集体的系统研究,认为缝洞型储集体可以分为古溶洞充填体、溶洞口藻(礁)灰岩发育带和受溶洞影响的围岩带3大类。其中,栉壳状弱胶结的搬运型角砾岩、垮塌角砾岩、层状藻(礁)灰岩、海绵状藻(礁)灰岩、颗粒状藻(礁)灰岩、丛状藻(礁)灰岩和层状分布的砂糖状淀积岩等岩石可能形成良好的储集体。缝洞型组合主要可以分为风化壳型和沿断裂分布的断裂型2种模式。综合塔河油田地下奥陶系储层和巴楚野外露头奥陶系古溶洞对比研究认为,塔里木盆地缝洞型碳酸盐岩储集体从下到上大致可以分为4个带:①物理沉积带,包括Ⅰ搬运型沉积岩带和Ⅲ垮塌角砾岩堆积带;②淀积岩发育带,包括Ⅳ淀积岩发育带、Ⅴ淀积岩之间的未充填层、Ⅵ含砾砂岩包壳层;③围岩影响带,包括Ⅶ破碎带、Ⅷ破裂带;④未影响围岩层Ⅸ。参照缝洞型碳酸盐岩综合垂向岩石序列,根据岩心缺失段的上下围岩特征,结合单井的的测井曲线特征和古地貌特征能够预测出岩心缺失段的岩石特征。露头古溶洞充填体中藻(礁)灰岩良好储层的发现,以及塔河油田可能存在有藻(礁)灰岩储层的证据表明,塔里木盆地很可能存在有藻(礁)灰岩储集体,这为油田下一步勘探和寻找新的储集体指明了方向。奥陶系露头缝洞型碳酸盐岩储集体岩石孔隙度的系统测试为塔河油田缝洞型碳酸盐岩油藏的储量计算提供了参数依据。更多还原

【Abstract】 With the deepening of Tarim basin exploration in carbonate reservoir, the importance of the fracture-cave reservoir is obvious. This reservoir often come from the Ordovician carbonate strata, has deeply buried, old, strong heterogeneity and cave complex in filling characteristics. Seriously restricted the oilfield exploration and development. This paper around this topic the characteristics of fracture-cave reservoir in carbonate. Comprehensive utilization of the wild outcrops, core and well logging, geophysical and analysis of test data, research about fracture-cave reservoirs using the comparative study on the underground reservoirs in Tahe oil field and Bachu outcrops.We researched the underground fracture-cave reservoir in Ordovician carbonate of Tahe oilfield in Tarim base.Tahe oilfield developped carbonate platform facies in the Ordovician, mainly by grainstone reservoir, limestone, baiyun ShiSha crumbs erythema shape limestone, algae (reef) limestone, dolomite, karst rock composed of six rock. The diagenesis phenomenon is complicated, weak cementation, late early compaction pressure and related to dissolve the formation, dissolve seam and karstification, mixed dolomitization in uplift period, broken and the formation of crack are conducive to the formation of good reservoir. Main diagenetic evolution characteristics of complex, the experience of subsea diagenesis, freshwater surface diagenesis environment and deeply buried diagenetic environment. There are mainly three types of reservoir spaces, inclued large cave, solution pores and crack. Fracture-cave reservoir can be divided into the hole, crack-type and fractured reservoir type. The big cave reservoir is the most important research area of fracture-cave reservoir. According to the distance form the top of cave to the surface layer of T74, three belts in vertical, including 0-60m, 60-150m and greater than 150m, and on the plane, reservoir can be divided into two layers. The fracture-cave reservoir in Ordovician carbonate of Tahe oilfield be controled by karst paleogeomorphology , palaeodrainage system and fault. In ancient landform and fault fracture zone and the fracture-cave reservoirs are more development. Through researched the fracture-cave reservoir in Ordovician carbonate of Bachu field outcrops in the Tarim basin in detail.We found that cave fillings can be divided into four types by lithology and causes,including Mechanical sediments, algal limestones (reef), chemical deposition and breccia landslide. Among them, seven kinds of cave fillings may be devoleped good reservoirs,including weakly cemented breccia, layered algae (reef) limestone, cavernous algae (reef) limestone, granular algae (reef) limestone, luminal algae (reef) limestone, layer distribution of sugar shape deposition. There are two kinds of combination patterns in fracture-cave reservoi mainly.One is devoleped be controlled by weathering profile, the other is devoleped along the fracture.The comprehensive the comparative study on cave in Ordovician carbonate in Tahe oilfield underground reservoir and Bachu field outcrop, we found there are four zones from bottom to top in fracture-cave reservoirs in Ordovician carbonate of Tarim basin, including①Physical and biological chemical interaction with sedimentary belt,including mechanical deposition belt(Ⅰ), algal limestones and (reef) belt (Ⅱ),and collapse breccia accumulation(Ⅲ).②Chemical deposition rocks, including deposition rocks(Ⅳ), the empty layer between deposition (Ⅴ) and gravel sandstone containing calcite shell (Ⅵ).③the surrounding rocks belt be influenced by caves, including rupture zone(Ⅶ) and fracture zone(Ⅷ).④Normal surrounding rock strata(Ⅸ). In a reference type carbonate rocks, comprehensive vertical sequence according to surrounding rock of the core of the missing interval, combined with the characteristics of well logging curves and topographical features can predict the rock characteristics of the core of the missing interval. The found that algal limestones (reef) is a good reservoir in the cave filling of outcrops, and some evidence about algal limestones reservoirs (reef) in Ordovician carbonate reservoir in Tahe oilfield, these might mean that algal limestones (reef) is a good reservoir in Tarim basin, there are probably guidance the further exploration and find new oil reservoir. The date of rock porosity testing in Outcrop fracture-cave reservoir in Ordovician can provide good parameters for oil reserves evaluation and calculation.更多还原