准噶尔盆地玛湖凹陷风城组储层致密化过程与成藏模式研究——以玛西地区风二段为例  

Reservoir Densification Process and Accumulation Model of Fengcheng Formation in Mahu Sag,Junggar Basin:A Case Study of Section 2 Feng in Maxi Area

作　　者：李卉[1] 刘新龙 周作铭[1] 阿不力孜·克力木 姜懿洋[1] 任海姣 刘得光[1] 李娜[1] 马银山 LI Hui;LIU Xinlong;ZHOU Zuoming;ABULIZI Kelimu;JIANG Yiyang;REN Haijiao;LIU Deguang;LI Na;MA Yinshan(Research Institute of Exploration and Development,PetroChina Xinjiang Oilfield Company,Karamay,Xinjiang 834000;Chinese Academy of Geological Sciences,Beijing 100037)

机构地区：[1]中国石油新疆油田分公司勘探开发研究院,新疆克拉玛依834000 [2]中国地质科学院,北京100037

出　　处：《地球学报》2024年第6期1023-1032,共10页Acta Geoscientica Sinica

基　　金：中国石油天然气股份有限公司前瞻性基础性研究重大科技项目“准噶尔盆地二叠系全油气系统地质理论与勘探实践”(编号:2021DJ0108);国家自然科学基金项目“基于仿生学模拟的致密砂体润湿性变化规律与油气运聚研究”(编号:41902142)。

摘　　要：准噶尔盆地玛湖凹陷风城组作为全油气系统的典型实例,是未来规模油藏勘探开发的潜在区域。本文以岩心、铸体薄片及生产动态等资料为基础,明确了玛湖凹陷风城组储层致密化过程与油气成藏模式。取得认识如下:1)晚二叠世压实作用起主导作用,风二段盐类矿物、结晶白云石脱玻化作用形成较多微小孔隙空间;早三叠世有机酸的溶蚀作用促进了储层空间的有效发育,早侏罗世白云化作用强烈,有机酸进一步溶蚀长石、碳酸盐矿物;2)晚二叠世风城组储层未致密,早三叠中后期部分岩相开始致密化,至早侏罗世开始大部分储层已致密,仅储层局部存在甜点区;3)晚二叠世成藏动力表现为浮力和生烃增压共同发挥作用,早三叠世以后逐渐以生烃增压为主要动力,发展成为源内—近源—源外的全油气系统成藏特点。通过上述研究,以期为玛湖凹陷风城组下一步油气勘探提供支撑。Fengcheng Formation in the Mahu Depression of Junggar Basin,a typical example of the whole oil and gas system,is a potential area for exploration and development of large-scale oil reservoirs in the future.To better understand the reservoir densification process and hydrocarbon accumulation model of the Fengcheng Formation in the Mahu Depression,this study using XRD,SEM,and other experimental data based on core,cast thin slice,and production dynamics.Our investigation yielded the following results:1)Compaction played a leading role in the Late Permian.Moreover,salt mineral and crystalline dolomite devitrification in the second member of Fenghe resulted in more micropore space.The Early Triassic organic acid dissolution created reservoir space and favorable conditions.The Early Jurassic was characterized by intense dolomitization and the organic acids further dissolved feldspar and carbonate minerals.2)The reservoirs of the Late Permian Shifengcheng Formation were not dense;certain lithofacies began to densify in the Middle and Late Early Triassic.Most reservoirs became dense from the Early Jurassic with only local sweet spots.3)In the Late Permian,buoyancy and hydrocarbon generation pressurization,combinedly played a role.After the Early Triassic century,hydrocarbon generation pressurization gradually became the major driving force and developed into a characteristic process of the entire hydrocarbon system.The aforementioned results are expected to provide support for the upcoming oil and gas exploration of the Fengcheng Formation in the Mahu Depression.

关 键 词：准噶尔盆地 玛湖凹陷 风城组 成藏模式 

分 类 号：P618.13[天文地球—矿床学]