Pore Structure Characteristics and Fluid Mobility of Tight Reservoir Based on Nuclear Magnetic Resonance: A Case Study of Jurassic in Wudun Sag, Dunhuang Basin
-
摘要:
致密储层孔喉细小，流体可动性评价难度大，影响着致密油藏储层物性表征及开发潜力分析。本研究针对敦煌盆地五墩凹陷侏罗系致密储层岩心，采用低场核磁共振技术，结合XRD全岩矿物分析、铸体薄片与扫描电镜照片，系统梳理了核磁共振T2谱与孔喉半径的对应关系，实现了致密储层孔径定量表征，阐明了储层孔喉分布特征，并明确了不同孔隙结构的流体可动性。结果表明：五墩凹陷核磁共振T2谱多为双峰型，左峰优势型占65%，双峰均势型占35%，粒间孔半径为6×10−3～600×10−3 μm，溶蚀孔半径为0.6～4 μm，微裂缝半径大于4 μm；各井孔喉半径分布差异大：XC1井以粒间孔优势型为主，溶蚀孔比例变化大，D1井均为粒间孔优势型，孔喉半径分布曲线形态变化较小，D2井发育粒间孔优势型及双孔均势型，粒间孔、溶蚀孔比例变化大，DX3井为双孔均势型，整体信号强度小；通过对饱和水、束缚水及残余油状态的岩心进行核磁测试，反映出溶蚀孔对流体可动性的贡献大。五墩凹陷后期的勘探方向为寻求孔隙结构发育程度及溶蚀孔比例“双高”的井区。研究成果对于该区致密油藏的勘探与开发具有重要的指导意义。
Abstract:The pore throat of tight reservoir is small, and the fluid mobility evaluation is difficult, which affects the characterization of tight reservoir physical properties and development potential analysis. In this study, low-field nuclear magnetic resonance technology was applied to the Jurassic tight reservoir core in the Wudun Sag of Dunhuang Basin, combining with XRD whole-rock mineral analysis, cast thin section and scanning electron microscope photos to systematically clarify the corresponding relationship between NMR T2 spectrum and pore throat radius, thus realizing the quantitative characterization of tight reservoir pore diameter and illustrating the distribution characteristics of pore throat. The fluid mobility of different pore structures is also defined. The results show that the NMR T2 spectra of Wudun sag are mainly bimodal, with the left peak dominant type accounting for 65% and the bimodal equilibrium type accounting for 35%. The radius of intergranular pore is 6×10−3～600×10−3 μm, the radius of dissolution pore is 0.6～4 μm, and the radius of microfracture is greater than 4μm. The distribution of pore throat radius varies greatly among all Wells: XC1 is dominated by intergranular pore dominance with large change in the proportion of dissolved pore; D1 is dominated by intergranular pore dominance with small change in the distribution curve of pore throat radius; D2 is characterized by intergranular pore dominance and double pore equilibrium with large change in the proportion of intergranular pore and dissolution pore; DX3 is characterized by double pore equilibrium with small overall signal intensity; Through the nuclear magnetic test of saturated water, bound water and residual oil state of the core, it shows that the contribution of the dissolution hole to the fluid mobility is great. The exploration direction of the late Wudun sag is to seek for the well area with the development degree of pore structure and the proportion of dissolution holes "double high". The above results and understanding have important guiding significance for the exploration and development of tight oil reservoirs in this area.
-
Key words:
- tight oil reservoir /
- Wudun depression /
- nuclear magnetic resonance /
- pore structure /
- fluid mobility
-
-
表 1 五墩凹陷核磁共振测试样品
Table 1. NMR test samples of Wudun depression
井号 样品编号 深度（m） 岩性 孔隙度（%） 渗透率（10−3 μm2） XC1 XC1-1 2293.2 灰色油斑砾状砂岩 4.90 0.24 XC1-2 2293.5 灰色油斑砂砾岩 5.06 0.05 XC1-3 2294.7 灰色油斑砂砾岩 3.83 0.25 XC1-4 2349.3 灰色荧光中砾岩 7.08 0.11 XC1-5 2356.4 灰色荧光细砾岩 11.30 3.89 D1 D1-1 1923.6 灰色油斑含砾细砂岩 6.99 0.36 D1-2 1926.6 灰色油斑含砾细砂岩 3.07 0.06 D1-3 1928.8 灰色油斑含砾细砂岩 7.39 2.73 D1-4 1930.3 灰色油斑含砾细砂岩 6.66 0.17 D2 D2-1 2270.0 灰色荧光含砾中砂岩 8.19 0.06 D2-2 2272.5 灰色油斑含砾细砂岩 10.15 0.18 D2-3 2363.0 灰色砂砾岩 2.71 0.01 D2-4 2397.0 灰色砂砾岩 4.67 0.01 DX3 DX3-1 2015.8 灰色荧光含砾细砂岩 4.47 0.03 DX3-2 2140.0 灰色油斑砂砾岩 8.28 5.95 DX3-3 2147.0 灰褐色油浸含砾细砂岩 7.78 1.34 DX3-4 2251.0 灰色荧光含砾细砂岩 5.60 0.15 
下载: 导出CSV
-
[1] 蔡利飘, 侯旭波, 崔红庄, 等. 敦煌盆地五墩凹陷中侏罗统中间沟组储层致密化过程分析[J]. 地质科学, 2022, 57（2）: 478−494.
CAI Lipiao, HOU Xubo, CUI Hongzhuang, et al. Reservoir densification process of Middle Jurassic Zhonggou Formation in Wudun Sag, Dunhuang Basin[J]. Scientia Geologica Sinica,2022,57(2):478−494.
[2] 曹力伟. 敦煌盆地五墩凹陷周缘侏罗系露头沉积特征及油气勘探意义[J]. 石油地质与工程, 2018, 32（6）: 6−11.
CAO Liwei. Sedimentary characteristics of Jurassic outcrop around Wudun Sag in Dunhuang Basin and its significance for oil and gas exploration[J]. Petroleum Geology and Engineering,2018,32(6):6−11.
[3] 程秀花, 李艳广, 叶美芳, 等. 西北地区地质实验测试技术研究进展及其在地质调查中的应用[J]. 西北地质, 2019, 55（3）: 170−190.
CHENG Xiuhua, LI Yanguang, YE Meifang, et al. Research progress of geological experimental testing technology and its application in geological survey in Northwest China[J]. Northwestern Geology,2019,55(3):170−190.
[4] 董艳蕾, 朱筱敏, 韦敏鹏, 等. 敦煌盆地五墩凹陷侏罗系层序地层格架与沉积体系分布[J]. 地学前缘, 2021, 28（1）: 177−189.
DONG Yanlei, ZHU Xiaomin, WEI Minpeng, et al. Distribution of Jurassic sequence stratigraphic framework and sedimentary system in Wudun Sag, Dunhuang Basin[J]. Earth Science Frontiers,2021,28(1):177−189.
[5] 付兰清. 致密砂岩动态渗吸排驱核磁共振在线实验——以松辽盆地北部扶余油层为例[J]. 大庆石油地质与开发, 2023, 42（3）: 66−74.
FU Lanqing. NMR Online experiment on dynamic imbibition drainage of tight sandstone: A case study of Fuyu Reservoir in northern Songliao Basin[J]. Petroleum Geology and Development in Daqing,2023,42(3):66−74.
[6] 付瑜, 柳益群, 蒋宜勤, 等. 准噶尔盆地西北缘玛湖凹陷三叠系百口泉组砂砾岩储层孔隙结构及渗流特征[J]. 西北地质, 2020, 53（2）: 223−234.
FU Yu, LIU Yiqun, JIANG Yiqin, et al. Pore structure and seepage characteristics of sandstone conglomerate reservoir of Triassic Baikouquan Formation in Mahu Sag, Northwest margin of Junggar Basin[J]. Northwestern Geology,2020,53(2):223−234.
[7] 高强勇, 王昕, 高建英, 等. 致密岩心核磁共振孔隙度影响因素分析[J]. 测井技术, 2021, 45（4）: 424−430.
GAO Qiangyong, WANG Xin, GAO Jianying, et al. Analysis of influencing factors of tight core porosity by NMR[J]. Well Logging Technology,2021,45(4):424−430.
[8] 侯娟, 黄帅博, 柯思, 等. 旬宜地区延长组长7致密油特征与富集主控因素[J]. 西北地质, 2021, 54（4）: 171−179.
HOU Juan, HUANG Shuaibo, KE Si, et al. Characteristics and main controlling factors of tight oil enrichment in Chang 7 of Yanchang Formation in Xianyi area[J]. Northwestern Geology,2021,54(4):171−179.
[9] 姜亭, 周俊林, 牛亚卓, 等. 西北公益性油气地质调查进展和展望[J]. 西北地质, 2022, 55（3）: 64−80.
JIANG Ting, ZHOU Junlin, NIU Yazhuo, et al. Progress and prospect of public welfare petroleum geological survey in Northwest China[J]. Northwestern Geology,2022,55(3):64−80.
[10] 井康康, 董旭, 蔺广泉, 等. 低渗储层孔隙结构的分形特征研究——以鄂尔多斯盆地永宁油田顺宁—洛河北区长6储层为例[J]. 非常规油气, 2021（4）: 19−25.
JING Kangkang, DONG Xu, LIN Guangquan, et al. Study on fractal characteristics of pore structure in low permeability reservoir——A case study of Chang6 reservoir in Shunning—Luohe north area in Yongning Oilfield, Ordos Basin[J]. Unconventional Oil & Gas,2021(4):19−25.
[11] 刘成, 王栋, 柳雪青, 等. 基于核磁共振技术的大庆油田X6东区剩余油分布特征研究[J]. 非常规油气, 2022, 9（3）: 96−102.
LIU Cheng, WANG Dong, LIU Xueqing, et al. Study on distribution characteristics of residual oil in eastern X6 block of Daqing Oilfield based on nuclear magnetic resonance[J]. Unconventional Oil & Gas,2022,9(3):96−102.
[12] 罗群, 高阳, 张泽元, 等. 中国与美国致密油形成条件对比研究[J]. 石油实验地质, 2022, 44（2）: 199−209.
LUO Qun, GAO Yang, ZHANG Zeyuan, et al. Comparative study on formation conditions of tight oil in China and the United States[J]. Petroleum Geology & Experiment,2022,44(2):199−209.
[13] 马凤春, 陈晓冬, 王琳, 等. 英东油田长井段薄互层油藏储层产能分类及预测研究[J]. 西北地质, 2021, 54（2）: 179−186.
MA Fengchun, CHEN Xiaodong, WANG Lin, et al. Study on reservoir productivity classification and prediction of thin interbedded reservoir in long well section of Yingdong Oilfield[J]. Northwestern Geology,2021,54(2):179−186.
[14] 宁凡, 赵欣, 邹妞妞, 等. 柴北缘侏罗系大煤沟组砂岩储层孔喉分布特征[J]. 非常规油气, 2022, 9（3）: 42−51.
NING Fan, ZHAO Xin, ZOU Niuniu, et al. Distribution characteristics of pore throat of sandstone reservoir of Jurassic Dameigou Formation in northern Qaidam Basin[J]. Unconventional Oil & Gas,2022,9(3):42−51.
[15] 任颖惠, 吴珂, 何康宁, 等. 核磁共振技术在研究超低渗-致密油储层可动流体中的应用——以鄂尔多斯盆地陇东地区延长组为例[J]. 矿物岩石, 2017, 37（1）: 103−110.
REN Yinghui, WU Ke, HE Kangning, et al. Application of nuclear magnetic resonance technology in the study of mobile fluid in ultra-low permeability and tight oil reservoirs: A case study of Yanchang Formation in Longdong area, Ordos Basin[J]. Journal of Mineralogy and Petrology,2017,37(1):103−110.
[16] 孙中良, 李志明, 申宝剑, 等. 核磁共振技术在页岩油气储层评价中的应用[J]. 石油实验地质, 2022, 44（5）: 930−940.
SUN Zhongliang, LI Zhiming, SHEN Baojian, et al. Application of nuclear magnetic resonance technology in shale oil and gas reservoir evaluation[J]. Petroleum Geology & Experiment,2022,44(5):930−940.
[17] 王俊, 黎明, 安超, 等. 渭北油田长3储层孔隙结构特征研究[J]. 非常规油气, 2021, 8（4）: 11−18.
WANG Jun, LI Ming, AN Chao, et al. Study of pore structure characteristics of Chang3 reservoir in Weibei Oilfield[J]. Unconventional Oil & Gas,2021,8(4):11−18.
[18] 吴松涛, 林士尧, 晁代君, 等. 基于孔隙结构控制的致密砂岩可动流体评价——以鄂尔多斯盆地华庆地区上三叠统长6致密砂岩为例[J]. 天然气地球科学, 2019, 30（8）: 1222−1232.
WU Songtao, LIN Shiyao, CHAO Daijun, et al. Dynamic fluid evaluation of tight sandstone based on pore structure control: A case study of Upper Triassic Chang 6 tight sandstone in Huaqing area, Ordos Basin[J]. Natural Gas Geoscience,2019,30(8):1222−1232.
[19] 肖文联, 杨玉斌, 李闽, 等. 鄂尔多斯盆地不同类型储集层水驱油特征实验[J]. 石油勘探与开发, 2021, 48（4）: 807−816.
XIAO Wenlian, YANG Yubin, LI Min, et al. Experimental study on water flooding characteristics of different types of reservoirs in Ordos Basin[J]. Petroleum Exploration and Development,2021,48(4):807−816.
[20] 张磊, 石军太, 张庆辉, 等. 鄂尔多斯盆地东南部页岩核磁共振实验研究[J]. 煤炭学报, 2018, 43（10）: 2876−2885.
ZHANG Lei, SHI Juntai, ZHANG Qinghui, et al. Experimental study on nuclear magnetic resonance of shale in southeastern Ordos Basin[J]. Journal of China Coal Society,2018,43(10):2876−2885.
[21] 于春勇. 富县地区长8致密砂岩储层孔隙结构特征及形成机理[J]. 非常规油气, 2021, 8（1）: 15−25.
YU Chunyong. Pore structure characteristics and formation mechanism of Chang 8 member tight sandstone reservoir in Fuxian area[J]. Unconventional Oil & Gas,2021,8(1):15−25.
[22] 张庆辉, 张磊, 吴克柳, 等. 基于核磁共振的湖相致密储层储集空间类型特征及开发潜力评价: 以柴达木盆地英西地区为例[J]. 中南大学学报(自然科学版), 2021, 52（2）: 498−508.
ZHANG Qinghui, ZHANG Lei, WU Keliu, et al. Reservoir space type characteristics and development potential evaluation of lacustrine tight reservoir based on nuclear magnetic resonance: A case study of Yingxi area, Qaidam Basin[J]. Journal of Central South University (Science and Technology),2021,52(2):498−508.
[23] 张学才, 李家贵, 刘全稳. 甘肃敦煌盆地五墩凹陷致密油成藏地质条件[J]. 地球科学与环境学报, 2017, 39（2）: 248−254.
ZHANG Xuecai, LI Jiagui, LIU Quanwen. Geological conditions of tight oil accumulation in Wudun Sag, Dunhuang Basin, Gansu Province[J]. Journal of Earth Sciences and Environment,2017,39(2):248−254.
[24] 周能武, 卢双舫, 王民, 等. 中国典型陆相盆地致密油成储界限与分级评价标准[J]. 石油勘探与开发, 2021, 48（5）: 939−949.
ZHOU Nengwu, LU Shuangfang, WANG Min, et al. Reservoir limits and grading evaluation criteria of tight oil in typical continental basins in China[J]. Petroleum Exploration and Development,2021,48(5):939−949.
-
图(6)
表(1)
计量
- 文章访问数: 781
- PDF下载数: 87
- 施引文献: 0