川西北中二叠统栖霞组、茅口组碳酸盐岩储层沉积学
摘要
全球油气总量近一半发现于前陆盆地，其具有极为良好的油气资源潜力。而龙门山推覆构造带中生界海相碳酸盐岩油气显示非常普遍，指示该构造带海相碳酸盐岩具备良好的油气资源潜力和勘探远景。因此对于研究龙门山推覆构造带内栖霞组、茅口组等储层成因和保存机制这一重要科学问题显得尤为重要，特别是系统研究四川盆地西缘的盆山耦合效应，精细刻画川西北地区前陆盆地演化历史，深刻揭示造山推覆构造带的分布格局、海-陆相盆地的转化过程、推覆体下盘及前缘的二叠系海相碳酸盐岩沉积相和对储层叠加改造机理，对下一步在该地区优选有利栖霞组、茅口组储集部位，及其发育特征和分布规律，提高储层预测和评价的成功率，有利天然气勘探目标区优选具有重大的现实意义。
本文在对国内外碳酸盐储层研究现状及栖霞组、茅口组白云岩成因研究现状调研基础上，并以碳酸盐岩储层沉积学理论、储层地质学、层序地层学、地球化学、沉积动力学、大地构造学等多学科理论为指导，结合野外实测剖面、钻井岩心描述，测井资料与地震资料，按照宏观与微观相结合，地质与测井相结合的方法，对川西北地区中二叠统栖霞组、茅口组碳酸盐岩的开展了储层沉积学研究，主要取得了如下几点成果和认识：（1）根据野外露头、岩石学、古生物化石、测井相标志、地震相剖面等综合对比，将川西北地区中二叠统地层划分方案进行了重新厘定和细分，将川西北地区中二叠栖霞组划分两段、茅
口组划分为4段，研究区中二叠统为一套开阔台地→台地边缘→台地前缘缓斜坡→盆地组合，具有典型的由浅变深的相带演化特征。
（2）根据野外剖面观察、钻井岩心描述，结合测井和地震资料，识别出研究区主要发育碳酸盐台地沉积体系，进一步识别出开阔台地、台地边缘、前缘缓斜坡及盆地4个亚相及众多微相类型。以连井沉积相剖面对比、沉积相平面分布特征和纵向演化分析为基础，进一步揭示出川西北地区中二叠统多期次海进—海退旋回演化过程，并建立了川西北地区以“缓斜坡镶边台地”沉积的模式。结合区域构造演化历史，编制完成栖霞组、茅口组沉积相平面展布图，并分析对各相带展布规律、几何形态、分布特点对储层的贡献和影响，为下一步川西北地区栖霞组、茅口组白云岩储层预测提供支撑。
（3）基于大量野外及岩心观察、薄片鉴定为基础，结合微量元素地球化学、同位素地球化学等分析，认为栖霞组和茅口组白云岩经历了强烈的成岩演化历史，成岩流体受海水和温度的影响较大，伴随地层加厚、地温梯度升高，早期白云岩等发生重结晶作用，期间部分成岩热液沿构造裂隙混入后，形成少量具有鞍形白云石等典型矿物，栖霞
组和茅口组白云岩的成因为埋藏白云岩化和构造热液白云岩化叠加作用的结果。
（4）针对研究区大深1井栖霞组、茅口组碳酸盐岩裂缝型储层成因研究表明：储层裂缝发育密集，主要以构造缝为主，溶蚀缝和缝合线发育较差，且裂缝发育与地层深度关系不明显，受多期区域构造运动强烈影响，裂缝节理产状与区域主构造应力方向一致性较好，指示栖霞组、茅口组地层经历早期构造挤压抬升、后期伸展松弛过程中，地层沿层理和劈理面破裂形成现今广泛发育裂缝型储层。
（5）川西北地区栖霞-茅口组储层储集空间以晶间孔和裂缝为主，总体属于低、特低孔特低渗型储层。储层主要为晶粒（细晶、中晶、粗晶及马鞍状）白云岩形成的孔隙型储层和生屑灰岩形成的裂缝型储层。
（6）川西北地区，栖霞组、茅口组碳酸盐岩储层主要分布于“镶边缓斜坡台地”模式中的台地边缘浅滩相带，在高能环境下形成早期的颗粒灰岩，成岩阶段伴随储层由同生-浅-中-深埋藏逐步过渡，白云化流体溶蚀作用进一步加强，原生孔隙基本消失殆尽，同时，天青石化、硅化、沥青充填持续充填进一步缩小了部分储渗空间，对储层物性有一定的影响，但从总体上看，由白云石化作用、溶蚀作用、后期破裂作用形成的各类储、渗空间是形成优质储层的关键因素。
skid关键词：中二叠统；栖霞组；茅口组；碳酸盐岩储层；沉积学特征；川西北地区大学体验英语综合教程3
Sedimentological rearch on the carbonate rervoir of Chihsia and Maokou formation in Northwest Sichuan
Abstract
Around the world nearly half of the oil and gas resources had been found in the foreland basin and had a great potential. While the oil and gas are very common in marine carbonate of Mesozoic located in Longmenshan nappe tectonic belt, Indicates has a potential and exploration prospect. Since than the mechanism and origin of Chihsia and Maokou formation rervoir of middle Permian is very necessary, Especially the rearch of basin-mountain coupling effect and evolution history and distribution pattern is benefits to optimize the exploration targets and favorable area.
Bad on the analysis of the domestic and overas rearch situation of carbonate rervoir,, according to the theory of carbonate rervoir dimentology, rervoir geology, quence stratigraphy, geochemistry and dimentary dynamics, geotectonics and other multi-disciplinary theory , then combining with the measured geological ction , drilling core description, logging data and ismic data, we achieved the folling results about the rervoir dimentology of Chihsia Formation and Maokou formation of the Sichuan basin:
(1)The Permian stratigraphic classification scheme system in northwest sichuan is reclassified , and Chihsia formation divided into two gment and Maokou is four in this rearch, there have a typical
facies from the shallow to deep a, such as the combination facies of open platform, platform margin, ramp of front platform and basin.
despi(2)The carbonate platform dimentary system in this rearch area is further divided into such subfacies as open platform , platform margin , ramp of front platform and baisn, bad on the plane distribution rule of Permian dimentation is summarized through stratigra phic correlationand dimentary facies analysis, which esablished the dimentary model of “ shelving rimmed carbonate platform”,then the plane distributive maps of dimentary facies of Chihsia and Maokou formation are drawn for predicting rervoir.
(3)The early dolomite predicted tobe the recrystallization of the fine dolomite under the e ffect of hydrothermal fluid as the thickening and geothemal gradient ri , which formed the typical minerals such as the saddle dolomite,and the origin of Chihsia and Maokou formation dolomite is buried dolomization and tectonic hydrothermal dolomization superpos ition reconstruction
(4)The results of origin rearch about carbonate rervoir shows that: under the effect of regional tectonics many structural fractures are not associated with the strata depth, but the joint occurrence
of fractures is good consistency with the regional teconic stress direction, indicate the tectonic uplift and later relaxation are major factors for Chihsia and Maokou formation carbonate fractures rervoir.
投诉信英文
(5)The intracrystalline pore and fissures constitutes the rervoir space of Chihsia and Maokou formation is especially low pore and low permeability rervoir in northeast of Sichu an,Lithologically, the revoir formation is compod mainly of crystalline( aplite,medium,co ar and saddle) dolostone forming a typical fractured-porous rervoir.alphabet
(6)The carbonate rervoir of Chihsia and Maokou formation is mainly distributed in the platform margin facies ,and the lithology of rervoir is granular grain limestone in the early stage ,then the contemporaneous, shallow burying, medium burying and deep burying process gradually transition,and the dolomitization transformed the rervoir storage space, ch anged the original rock fabric,improved the dissolution fluid space,while the celestine, silicati zation and asphalt filled the few spaces, in general the dolomitization, dissolution, fracturation plag a important role in the forming high quality rervior.
Key Words:Middle permian; Chihsia formation; Maokou formation; Carbonate rervoir; Sedimentary characteristics; Northwest of Sichuan
目录
摘要........................................................................................................................................... I Abstract .................................................................................................................................... III 目录....................................................................................................................................... V 第1章前言. (1)
1.1选题来源 (1)
1.2选题依据及研究意义 (2)
1.2.1选题依据 (2)
1.2.2研究意义 (3)
1.3研究现状 (4)
1.3.1 碳酸盐岩研究现状 (4)
1.3.2 白云岩成因研究现状 (5)
better than a hallelujah1.3.3 栖霞组和茅口组白云岩成因研究现状 (11)
1.3.4 储层裂缝研究现状 (13)
1.4研究方法内容及技术路线 (15)
1.4.1 研究内容 (16)
1.4.2 主要完成工作量 (18)
1.5论文创新点 (19)
第2章地质概况 (21)
2.1 区域构造特征 (21)
非常想2.2地层特征 (25)
2.3构造-沉积演化模式 (27)
2.3.1构造演化阶段划分及特征 (27)
2.3.2构造演化分析 (29)
第3章川西北地区栖霞组、茅口组沉积相特征 (34)
3.1沉积相标志 (34)
3.1.1 岩石学标志 (34)
extensive3.1.2 古生物标志 (36)
3.1.3 测井相标志 (37)
3.1.4 地震相标志 (38)
toobigtofail
3.2沉积相划分及特征 (39)
3.2.1 沉积相划分 (39)feel
3.2.2 沉积相特征 (40)
3.2.3 沉积相剖面分析 (44)
