论文部分内容阅读
综合利用野外剖面、钻井岩心观察、薄片鉴定以及物性测试等资料,辅以阴极发光、碳—氧同位素和电子探针等地球化学分析手段,对巴楚地区寒武系碳酸盐岩储层特征及主控因素进行系统研究。结果表明:研究区寒武系发育盐上白云岩(丘里塔格组)、盐间云灰岩(沙依里克组)和盐下白云岩(肖尔布拉克组)3套储集层。盐上和盐下白云岩储层主要由(残余)颗粒白云岩、粉—细晶白云岩和具有微生物结构的白云岩组成,储层类型以溶蚀孔洞型和裂缝—溶蚀孔洞型为主;储层发育受沉积相和多期溶蚀作用控制:高能相带(颗粒滩、微生物丘)和膏岩—碳酸盐岩过渡相带(含膏云坪)构成储层发育的基础;准同生期层间岩溶进一步叠加改造,形成大量顺层溶蚀孔洞层,在纵向上多期叠置、横向上似层状大面积展布,控制储层规模化发育;晚期热液溶蚀沿早期高孔渗带局部调整改造,但横向影响范围有限;另外,浅埋藏期适度的白云岩化有利于颗粒滩相白云岩孔隙的保存。盐间云灰岩储层以斑状或条带状白云质灰岩为主,孔隙主要发育在与生物钻孔或生物扰动有关的潜穴部位,生物扰动对于低能相带物性的改善具有积极意义。
Comprehensive utilization of field profiles, drilling core observations, sheet identification and physical testing data, combined with the cathodoluminescence, carbon-oxygen isotopes and electronic probes and other geochemical analysis methods, the Bachu Cambrian carbonate reservoir characteristics And the main control factors for systematic research. The results show that there are three sets of reservoirs in the Cambrian of the study area, ie, the salt-up dolomite (Quritag group), the inter-salt cloud limestone (Shayilk group), and the sub-salt dolomite . The salt and salt dolomite reservoirs are mainly composed of (residual) dolomite, pink-fine dolomite and dolomite with microbial structure. The reservoir types mainly include dissolved pore type and fracture-dissolved pore type. Layer development is controlled by sedimentary facies and multi-stage dissolution: the high-energy facies belts (granulite and microbial mounds) and the gypsum-carbonate transitional facies (including Gaoyunping) constitute the basis for reservoir development; The interlayer karst is further superposed and remodeled to form a large number of layers of etudes along the layers, which are superposed in the longitudinal direction and spread horizontally in a large scale to control the scale development of the reservoirs. Late hydrothermal dissolution along the early high-permeability zones Local adjustment and transformation, but the lateral impact of the limited; In addition, the shallow dolomitization of shallow burial period is conducive to the preservation of the pores of dolostone dolostone. The interbedded interbedded lithic limestone reservoirs are mainly patchy or banded dolomitic limestone. The pores mainly develop in the burrows associated with biological drilling or bioturbation. Bioturbation is of positive significance for the improvement of physical properties of low-energy facies.