苏里格气田上古生界连续型致密气形成过程  

Formation process of upper paleozoic continuous tight sandstone gas reservoir in the Sulige gas field

作　　者：杨智[1] 付金华[2] 刘新社[2] 吴松涛[1] 林森虎[1] 王岚 王怀厂[2] 

机构地区：[1]中国石油勘探开发研究院,北京100083 [2]中国石油长庆油田勘探开发研究院,陕西西安710021

出　　处：《深圳大学学报（理工版）》2016年第3期221-233,共13页Journal of Shenzhen University(Science and Engineering)

基　　金：国家重点基础研究发展计划资助项目(2014CB239000);国家科技重大专项基金资助项目(2016ZX05046)~~

摘　　要：苏里格气田上古生界致密砂岩储层叠置连片分布、多层位普遍含气,是典型的连续型致密砂岩大气区.利用生排烃物理模拟、数值模拟、岩矿观察、流体包裹体和碳氧同位素等手段,共同约束验证,综合分析相关成藏要素,探索恢复盆地大面积致密砂岩气形成的动态过程.研究发现,苏里格气田具有稳定平缓构造面貌（晚侏罗世至今,苏里格地区古构造坡降速一般为3-6 m/km）、高成熟煤系源岩广布式生排烃气和大面积致密砂岩储层叠置分布的成藏地质背景（生气强度大于1 600 kg/m2、砂体厚度大于15m的源储接触面积可达2.35×104km2,占苏里格气田面积的78%）;在晚侏罗世至早白垩世早期,苏里格气田具有规模充注和连续聚集的成藏特征;早白垩世晚期以后,其成藏特征缓慢调整,最终形成大面积连续型致密砂岩大气区.成岩成藏耦合关系和源储共生紧密接触,共同决定了苏里格气田近源连续聚集的成藏模式.近生气中心区的致密储集砂体是天然气勘探开发的有利区.Sulige gas field in Ordos basin,north-central China,is a typical large unconventional continuous tight gas reservoir characterized by continuous distribution of super-imposed gas layers with rich gas in large dimensions. This paper introduces an integrated analysis approach to study the formation process of target gas reservoir by combining several analytic measures, i. e., generation-expulsion physical simulation, numerical basin modeling, microphotographic observation,fluid inclusion test,and carbon-oxygen isotopic etc. The dynamic formation process of this large-scale gas reservoir is discussed. It is found that Sugli gas field has such reservoir formation characteristics as stable and gentle paleo-tectonic slope from late Jurassic to the present,as well as highly maturated coal measures with generally large hydrocarbon gas generation intensity（ more than 1 600 kg / m2）,and large-scale closelycontacted tight sandstones with over 15 meters in thickness and area of 2. 35 × 104km2（ about 78% of the whole Sulige zone）. The gas was charged and accumulated continuously and massively in tight reservoirs from late Jurassic to early Early-Cretaceous,and the large gas reservoir was finally formed after reconstruction after early LateCretaceous. This paper concludes two elements to determine the present distribution and accumulation of Sulige natural gas i. e. the coupled relationship between reservoir diagenesis and gas accumulation process,and the close contact between the gas generation source and tight sandstone reserves. The regions close to the center of gas generation could be the potential favorable areas for exploration and development of natural gas.

关 键 词：致密砂岩气 致密储层 生气强度 非常规油气 同位素 煤成气 苏里格气田 

分 类 号：TE311[石油与天然气工程—油气田开发工程]