摘要
通过物性、铸体薄片和带有能谱仪的扫描电镜,对鄂尔多斯盆地古峰庄—麻黄山地区延长组长82低渗透砂岩的致密化过程进行定量研究。结果表明,砂岩致密化过程中发生的主要成岩作用事件有4个,按成岩序列依次为早成岩阶段A期的方解石胶结和压实作用、早成岩阶段B期的绿泥石膜胶结以及中成岩阶段A期的长石溶蚀;经定量计算,砂岩的原始沉积物孔隙度为39.7%,渗透率为50 500×10^(-3)μm^2;早成岩阶段A期的方解石胶结和压实作用导致孔隙度和渗透率分别锐减为12.1%和1.07×10^(-3)μm^2,砂岩成为特低渗储层;早成岩阶段B期的绿泥石膜胶结引起孔隙度和渗透率进一步降低至10.8%和0.64×10(-3)μm^2,特低渗透砂岩变差为超低渗透砂岩;中成岩阶段A期的油气成藏过程中,长石发生溶蚀作用而产生次生孔隙,促使孔隙度和渗透率分别提高到12.4%和1.20×10^(-3)μm^2,超低渗透砂岩转化为特低渗透砂岩;古峰庄—麻黄山地区长82低渗透砂岩的致密化过程为"先致密后成藏,边成藏边扩容增渗"。
By core physical property, casting slice, scanning electron microscope analysis with energy disperse spectroscopy,the densification process of Chang 82 ultra-low permeability sandstone,Gufengzhuang- Mahuangshan area was studied.The study showed that there were four diagenetic events during densification process of the sandstone, which were calcite cement and compaction of early diagenesis stage A,chlorite film cement of early diagenesis stage B,and feldspar dissolution of middle diagenesis stage A on the ba sis of diagenetic sequence. By quantitative calculation, the initial porosity and permeability of sandstone in the area were 39.7% and 50 500×10^-3μm^2 respectively.In the courseof earlydiagenesis stage A,both calcite cement and mechanical compaction caused the sandstone to very low permeability reservoir whose porosity and permeability were 12.1% and 1.07 ×10^-3μm^2 separately. Then chlorite film in early diagenesis stage B converted very low permeability reservoir into ultra-low permeability reservoir whose porosity and permeability were 10.8 % and 0.64×10^-3μm^2 apart.During hydrocarbon accumulation in middle diagenesis stage A, feldspar dissolution formed secondary pore, authigenic quartz and kaolinite cement whose compre hensive effect made porosity and permeability up to 12.4% and 1.20×10^-3μm^2individually.So the densification process of Chang 82 ultra-low permeability sandstone,Gufengzhuang-Mahuangshan area is first den- sification then accumulation and accumulation with increasing porosity and permeability.
作者
屈雪峰
周晓峰
刘丽丽
丁黎
Qu Xue-feng1,2, Zhou Xiao-feng3,4,5, Liu Li-li1,2 ,Ding Li1,2(1.Research Institute of E~rploration and Development ,Changqing Oilfield Company ,PetroChina ,Xi＇an 710018 ,China ; 2.Exploration and Development National Project Laboratory of Low Permeability Oil and Gas Fields,Xi＇an 710018 ,China3.Collegue of Petroleum Engineering, China University of Petroleum ,Beijing 102249, China 4.MOE Key Laboratory of Petroleum Engineering ,China University of Petroleum ,Beijing 102249 ,China 5.State Key Laboratory of Petroleum Resources and Engineering ,Beijing 102249 ,China)
出处
《天然气地球科学》
EI
CAS
CSCD
北大核心
2018年第3期337-348,共12页
Natural Gas Geoscience
基金
国家科技重大专项"低渗-超低渗油藏有效开发关键技术(编号:2017ZX5013-004)"
国家科技重大专项"特低渗油藏有效开发技术"(编号:2011ZX05013-006)
中国石油天然气集团公司专项"长庆油田5000万吨持续高效稳产关键技术研究及应用(编号:2016E-0505)"联合资助
关键词
先致密后成藏
边成藏边扩容增渗
低渗透砂岩
长82
古峰庄-麻黄山地区
鄂尔多斯盆地
First densification then accumulation
Accumulation with increased porosity and permeability
Ultra-low permeability sandstone
Chang 82
Gufengzhuang-Mahuangshan area
Ordos Basin
