In response to the poor understanding of the diagenesis and reservoir formation effect of sandstones in Dongsheng Gasfield, Ordos Basin, the lithological characteristics, pore-permeability characteristics, reservoir space types and diagenetic characteristics of the reservoirs in Dongsheng Gasfield were studied in depth through core observation and description on the basis of slice observation, cathode luminescence, scanning electron microscope, X-ray diffraction and physical characteristic analysis, and other materials, the diagenetic evolution stages and evolutionary sequence of reservoir were determined, and the reservoir formation effect was discussed systematically. The results of the study showed that the reservoir sandstones of the lower Shihezi Formation in Dongsheng Gasfield, Ordos Basin were mainly in the Stage A of mesozone rock, and partly in Stage B of mesozone rock, with medium compositional maturity and low textural maturity; the secondary vugular pore was the main storage space, and the reservoir was a typical low-porosity and low-permeability reservoir; the sandstone diagenesis in the study area mainly included mechanical compaction, cementation and dissolution, among which mechanical compaction, carbonate cementation and siliceous cementation reduced the porosity and were important causes of reservoir densification, while the secondary pores formed by dissolution was conducive to improving the physical properties of the reservoir. The characteristics, diagenetic evolution and reservoir formation relationship of lower Shihezi Formation, Dongsheng Gasfield were studied in order to provide some reference and guidance for further exploration of tight sandstone gas in the study area.
[1] SURDAM R C.A new paradigm for gas exploration in anomalously pressured“tight gas sands”in the Rocky Mountain Laramide Basin[J].AAPG Memoir,1997,67(67):283-298.
[2] ZOU Caineng,TAO Shizhen,YUAN Xuanjun,et al.Global importance of“continuous”petroleum reservoirs:accumulation,distribution and evaluation[J].Petroleum Exploration and Development,2009,36(6):669-682.
[3] SPENCER C W.Geologic aspects of tight gas reservoirs in the Rocky Mountain Region[J].Journal of Petroleum Geology,1985,37(7):1308-1314.
[4] MILLER M,SHANLEY K.Petrophysics in tight gas reservoirs-key challenges still remain[J].Leading Edge,2010,29(12):1464-1469.
[5] 赵靖舟,付金华,姚泾利,等.鄂尔多斯盆地准连续型致密砂岩大气田成藏模式[J].石油学报, 2012, 33(1):37-52.
ZHAO Jingzhou,FU Jinhua,YAO Jingli,et al.Quasi-continuous accumulation model of large tight sandstone gas field in Ordos Basin[J].Acta Petrolei Sinica,2012,33(1):37-52.
[6] 邹才能,朱如凯,吴松涛,等.常规与非常规油气聚集类型、特征、机理及展望——以中国致密油和致密气为例[J].石油学报,2012,33(2):173-187.
ZOU Caineng,ZHU Rukai,WU Songtao,et al.Types, characteristics, genesis and prospects of conventional and unconventional hydrocarbon accumulations:taking tight oil and tight gas in China as an instance[J].Acta Petrolei Sinica,2012,33(2):173-187.
[7] 罗龙,高先志,孟万斌,等.深埋藏致密砂岩中相对优质储层形成机理——以川西坳陷新场构造带须家河组为例[J].地质学报,2017,38(6): 930-944.
LUO Long,GAO Xianzhi,MENG Wanbin,et al.The formation mechanism of the relatively high-quality reservoir in tight sandstones with deep burial:a case study of Xujiahe Formation in Xinchang Structural Belt of western Sichuan Depression[J].Acta Geologica Sinica,2017,38(6):930-944.
[8] 王峰,田景春,陈蓉,等.鄂尔多斯盆地北部上古生界盒8储层特征及控制因素分析[J].沉积学报,2009,27(2):238-245.
WANG Feng,TIAN Jingchun,CHEN Rong,et al.Analysis on controlling factors and characteristics of sandstone reservoir of He8 (upper paleozoic) in the northern Ordos Basin[J].Acta Sedimentologica Sinica,2009,27(2):238-245.
[9] 许磊,于兴河,杨勇,等.苏里格南部地区盒8段致密砂岩储层成岩作用及成岩相划分[J].天然气工业, 2012,32(7):15-20.
XU Lei,YU Xinghe,YANG Yong,et al.Diagenesis and diagenetic facies of tight sandstone reservoirs in the 8th member of the Shihezi Formation,southern Sulige Gas Field[J].Natural Gas Industry,2012,32(7):15-20.
[10] 田景春,吴琦,王峰,等.鄂尔多斯盆地下石盒子组盒8段储集砂体发育控制因素及沉积模式研究[J].岩石学报, 2011,27(8):2403-2412.
TIAN Jingchun,WU Qi,WANG Feng,et al.Research on development factors and the deposition model of large area reservoir sandstones of He8 section of Lower Shihezi Formation of Permian in Ordos Basin[J].Acta Petrologica Sinica,2011,27(8):2403-2412.
[11] 付金华,魏新善,南珺祥,等.鄂尔多斯盆地上古生界致密砂岩气田储集层特征与成因[J].古地理学报,2013,15(4):529-538.
FU Jinhua,WEI Xinshan,NAN Junxiang,et al.Characteristics and origin of reservoirs of gas fields in the Upper Paleozoic tight sandstone,Ordos Basin[J].Journal of Palaeogeography,2013,15(4):529-538.
[12] 李婕,赵俊兴,孔祥超,等.鄂北杭锦旗地区下石盒子组沉积相演化及控制因素[J].山东科技大学学报(自然科学版),2013,32(2):34-42.
LI Jie,ZHAO Junxing,KONG Xiangchao,et al.Sedimentary facies evolution and controlling factors of Lower Shihezi Formation in Hangjinqi Area,north Ordos Basin[J].Journal of Shandong University of Science and Technology(Natural Science),2013,32(2):34-42.
[13] 邱隆伟,穆相骥,李浩,等.鄂尔多斯盆地杭锦旗地区二叠系下石盒子组岩屑发育特征及其对储层物性的影响[J].石油与天然气地质, 2019, 40(1):28-37.
QIU Longwei,MU Xiangji,LI Hao,et al.Characteristics of detritus development in the Permian Lower Shihezi Formation in Hangjinqi Area and its influence on reservoir physical properties[J].Oil & Gas Geology,2019,40(1):28-37.
[14] 徐文玺,李凌川.鄂尔多斯盆地东胜气田二叠系中统下石盒子组储层评价[J].天然气勘探与开发, 2016, 39(2):18-21.
XU Wenxi,LI Lingchuan.Reservoir evaluation of the Middle Permian Lower Shihezi Formation,Dongsheng Gasfield,Ordos Basin[J].Natural Gas Exploration and Development,2016,39(2):18-21.
[15] 罗静兰, 张晓莉, 张云翔,等.成岩作用对河流—三角洲相砂岩储层物性演化的影响——以延长油区上三叠统延长组长2砂岩为例[J]. 沉积学报, 2001,19(4):541-547.
LUO Jinglan,ZHANG Xiaoli,ZHANG Yunxiang,et al.The diagenetic impact on reservoir-quality evolution of Fluvial-deltaic sandstones-taking an example from the Upper Triassic sandstones of Chang2 Formation in the Yanchang Oilfield[J].Acta Sedimentologica Sinica,2001,19(4):541-547.
[16] 邱隆伟,穆相骥,李浩,等.杭锦旗地区下石盒子组致密砂岩储层成岩作用对孔隙发育的影响[J].油气地质与采收率,2019,26(2):46-54.
QIU Longwei,MU Xiangji,LI Hao,et al.Influence of diagenesis of tight sandstone reservoir on the porosity development of Lower Shihezi Formation in Hangjinqi Area,Ordos Basin[J].Petroleum Geology and Recovery Efficiency,2019,26(2):46-54.
