Study on pore structure characteristics of tight sandstone in Block 4 of the central Junggar Basin
-
摘要: 致密砂岩孔隙结构是影响储层物性、储集性能和渗流特性的主要因素，准确表征岩石的孔隙结构特征是储层评价的重要内容之一。为此通过岩心观察、CT扫描成像及其图像处理等对准噶尔盆地中部4区块董11井致密砂岩储层孔隙结构特征进行了定性及定量综合研究。研究结果表明，采用USM锐化、阈值选取及中值滤波法对微CT扫描灰度图像进行图像处理，可以更好地区分岩石内部骨架和孔隙的边界，提高了图像的分割精度；当数字岩心立方体模型边长在450体素时，孔隙度趋近定值；研究区致密砂岩储层储集空间主要以粒间孔隙和微裂隙为主，伴有少量的解理裂隙，孤立孔隙较多，孔隙形状复杂，分布不均匀；研究区致密砂岩连续截面面孔率分布不均匀，离散性强，在连续截面上面孔率频繁出现极大值与极小值（跳跃性较大），容易在流体流动的过程中产生压降过大，造成部分孔隙喉道堵塞；研究区致密砂岩储层孔隙大小分布不均匀，孔隙直径在15~35 μm之间，占总孔隙数的60%左右，其面积占18%；直径在50~200 μm的孔隙数量占总孔隙数的20%，其面积占比达60%，为油气赋存提供了有利的储集空间。Abstract: The pore structure of tight sandstone is the major factor affecting physical property, performance and seepage characteristics of reservoir. The accurate characterization of rock pore structure is one of the important contents of reservoir evaluation. Therefore, the pore structure characteristics of tight sandstone reservoir in Well Dong-11, Block 4, central Junggar Basin were studied qualitatively and quantitatively through core observation, CT scanning imaging and image processing. The results show that:USM sharpening, threshold selection and median filtering were used for image processing of gray scale images in micro-CT scanning, which could better distinguish the boundary between skeleton and pore inside the rock and improve the image segmentation accuracy. Porosity tends to be constant when the side length of the digital core cube model is 450 voxel. The reservoir space of tight sandstone reservoirs in the study area is mainly composed of intergranular pores and micro-fractures, with a small number of cleavage fractures, and more isolated pores. Pores are characterized by complex shapes and uneven distribution. The porosity distribution of the continuous section of the tight sandstone in the study area is not uniform and highly discrete. The maximum and minimum values of porosity appear frequently on continuous sections (strong jumping), which is easy to cause excessive pressure drop in the process of fluid flow, resulting in partial pore throat blockage. The pore size distribution of tight sandstone reservoir in the study area is not uniform. The pore diameter is mainly from 15 microns to 35 microns, which accounts for about 60% of the total pore number, but its area only accounts for 18%. The pores take up 20% of the total number of pores from 50 microns to 200 microns in diameter, but the area takes up 60%, which provides favorable storage space for oil and gas.
-
Key words:
- tight sandstone /
- CT scanning /
- pore structure /
- digital core
-
图 5 研究区域及建立的三维灰度模型
Figure 5. The study area and the established three-dimensional grayscale model
图 8 不同尺寸下的三维孔隙几何模型
Figure 8. Three-dimensional pore geometry model under different sizes
图 9 孔隙度随模型边长的变化规律折线图
Figure 9. Line chart of the variation of porosity with the change of the side length of the model
图 11 孔隙度分布均匀性分析流程图
Figure 11. Flow chart of uniformity analysis of porosity distribution
图 12 不同方向连续面孔率分布曲线
Figure 12. Curves of continuous plane porosity distribution in diffierent direction
-
BAI B, ZHU R K, WU S T, et al., 2013. Multi-scale method of Nano(micro)-CT study on microscopic pore structure of tight sandstone of Yanchang Formation, Ordos Basin[J]. Petroleum Exploration and Development, 40(3):329-333. (in Chinese with English abstract) http://cn.bing.com/academic/profile?id=0ef02389d5b3b36564e98ee60201d442&encoded=0&v=paper_preview&mkt=zh-cn DONG H. 2007. Micro-CT imaging and pore network extraction[D]. London: Imperial College. FENG S B, NIU X B, LIU F, et al., 2013. Characteristics of Chang7 tight oil reservoir space in Ordos basin and its significance[J]. Journal of Central South University (Science and Technology), 44(11):4574-4580. (in Chinese with English abstract) http://cn.bing.com/academic/profile?id=3850d1f06765534a123c419f7f1d9cfd&encoded=0&v=paper_preview&mkt=zh-cn FENG Y, YANG W W, LIU Y C, et al., 2015. Analysis on causes of reservoir resistivity differences of Chang 81 reservoir in Zhenbei Oilfield, Ordos Basin[J]. Xinjiang Petroleum Geology, 36(5):526-530. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=xjsydz201505005 HAO L W, WANG Q, TANG J, 2013. Research progress of reservoir microscopic pore structure[J]. Lithologic Reservoirs, 25(5):123-128. (in Chinese with English abstract) http://cn.bing.com/academic/profile?id=11f9ba456a2519fcb2ccac2de1313a19&encoded=0&v=paper_preview&mkt=zh-cn HAO L W, WANG Q, TANG J, 2013. Research progress of reservoir microscopic pore structure[J]. Lithologic Reservoirs, 25(5):123-128. (in Chinese with English abstract) http://cn.bing.com/academic/profile?id=11f9ba456a2519fcb2ccac2de1313a19&encoded=0&v=paper_preview&mkt=zh-cn HE T, WANG F, WANG L L, 2013. Characteristics of micro-pore structure of tight sandstone reservoir:a case study from Chang 7 reservoir of Yanchang Formation in Ordos Basin[J]. Lithologic Reservoirs, 25(4):23-26. (in Chinese with English abstract) http://cn.bing.com/academic/profile?id=0665dc8e106cb2f846941f80081c33f3&encoded=0&v=paper_preview&mkt=zh-cn LI H Y, YUE D L, ZHANG X J, 2012. Characteristics of pore structure and reservoir evaluation of low permeability reservoir in Sulige gas field[J]. Earth Science Frontiers, 19(2):133-140. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=dxqy201202019 LI J, KONG X C, SONG M S, et al., 2019. Study on the influence of reservoir rock micro-pore structure on rock mechanical properties and crack propagation[J]. Rock and Soil Mechanics, 40(11):4149-4156, 4164. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=ytlx201911004 LI Y L, ZHANG Y F, CONG L, et al., 2016. Application of X-CT scanning technique in the characterization of micro pore structure of tight sandstone reservoir:an example from Fuyu Oil Layer in Daan Oilfield[J]. Journal of Jilin University (Earth Science Edition), 46(2):379-387. (in Chinese with English abstract) LI Z L, WANG M F, HU J X, et al., 2015. Research and realization of enhancement algorithm and feature extraction algorithm for medical images[J]. Computer Technology and Development, 25(1):115-118. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=wjfz201501026 LIN C Y, WU Y Q, REN L H, et al., 2018. Review of digital core modeling methods[J]. Progress in Geophysics, 33(2):679-689. (in Chinese with English abstract) http://cn.bing.com/academic/profile?id=efe77b9f9809ff6146ab09b53d74abcd&encoded=0&v=paper_preview&mkt=zh-cn LIU C T, QU H, LIU B J, 2011. Research of low permeability reservoir microscopic structure feature[J]. Science Technology and Engineering, 11(21):5002-5004. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=kxjsygc201121010 LIU H M, ZHENG J K, ZHAO W S, et al., 2019. A new method for evaluating brittleness index of deep tight sandstone reservoir[J]. Journal of Geomechanics, 25(4):492-500. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=dzlxxb201904006 LIU X F, ZHANG W W, SUN J M, 2013. Methods of constructing 3-D digital cores:a review[J]. Progress in Geophysics, 28(6):3066-3072. http://cn.bing.com/academic/profile?id=d8dc4d664f612d5b94dcbc14daad49c7&encoded=0&v=paper_preview&mkt=zh-cn LIU X J, ZHU H L, LIANG L X, 2014. Digital rock physics of sandstone based on Micro-CT technology[J]. Chinese Journal of Geophysics, 57(4):1133-1140. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=wthtjsjs201704019 LUO S S, WEI W, WEI X S, et al., 2013. Microstructural characterization and development trend of tight sandstone reservoirs[J]. Journal of Oil and Gas Technology, 35(9):5-10. (in Chinese with English abstract) http://cn.bing.com/academic/profile?id=1d80d0ab2c35984323fd9444abb4e6fa&encoded=0&v=paper_preview&mkt=zh-cn LUO Z T, WANG Y C, 1986. Pore structure of oil and gas reservoirs[M]. Beijing:Science Press. (in Chinese) MAO H H, WANG F H, CHEN C K, et al., 2012. Research and analysis of several CT image segmentation algorithm[J]. Computer and Digital Engineering, 40(1):101-103, 108. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=jsjyszgc201201034 SHE M, SHOU J F, ZHENG X P, et al., 2011. 3D high resolution reservoir characterization technique based on CT imaging and application[J]. Xinjiang Petroleum Geology, 32(6):664-666. (in Chinese with English abstract) http://cn.bing.com/academic/profile?id=37131775cfb272f566351f03b4295804&encoded=0&v=paper_preview&mkt=zh-cn WANG J L, GAO J, LIU L, 2009. Porosity characteristics of sandstone by X-ray CT scanning system[J]. Acta Petrolei Sinica, 30(6):887-893, 897. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=syxb200906015 YANG Z M, JIANG H Q, LI S T, et al., 2007. Characteristic parameters of microscopic pore structures of low permeability gas reservoirs:by using Sulige and Dina low permeability gas reservoirs for example[J]. Journal of Oil and Gas Technology, 29(6):108-110, 119. (in Chinese with English abstract) http://cn.bing.com/academic/profile?id=3b1c097e8e8ded3fd93b4786e99416dc&encoded=0&v=paper_preview&mkt=zh-cn YAO J, ZHAO X C, YI Y J, et al., 2005. The current situation and prospect on digital core technology[J]. Petroleum Geology and Recovery Efficiency, 12(6):52-54. (in Chinese with English abstract) YAO J, ZHAO X C, 2010. Theory of digital core and flow simulation in pore scale[M]. Beijing:Petroleum Industry Press. (in Chinese) YOU Y, NIU X B, FENG S B, et al., 2014. Study of pore features in Chang7 tight oil reservoir, Yanchang layer, Ordos Basin[J]. Journal of China University of Petroleum, 38(6):18-23. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=sydxxb201406003 YOU Y, NIU X B, LI T Y, et al., 2016. Application of CT scanning system to study of micro-pore structure of tight sandstone:a case study of Chang-7 member of Yanchang Formation in Ordos Basin[J]. Xinjiang Petroleum Geology, 37(2):227-230. (in Chinese with English abstract) https://www.sciencedirect.com/science/article/pii/S0920410516310191 ZHANG W, HE X, HUO Y X, et al., 2013. Bi-level image sharpening method based on parallel computing[J]. Journal of Computer Applications, 33(8):2325-2329. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=jsjyy201308057 ZHAO X C, YAO J, 2007. Construction of digital core and evaluation of its quality[J]. Journal of Xi'an Shiyou University (Natural Science Edition), 22(2):16-20. (in Chinese with English abstract) http://cn.bing.com/academic/profile?id=b20caf0d978357a0b1b7df08b99d4eaa&encoded=0&v=paper_preview&mkt=zh-cn ZHOU S W, XUE H Q, GUO W, 2017. A mineral analysis method for shale based on SEM and X-ray EDS[J]. China Petroleum Exploration, 22(6):27-33. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgsykt201706004 ZHU Y H, TAO G, 2007. Sequential indicator simulation technique and its application in 3D digital core modeling[J]. Well Logging Technology, 31(2):112-115. (in Chinese with English abstract) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=cjjs200702005 ZOU C N, ZHU R K, BAI B, et al., 2011. First discovery of Nano-pore throat in oil and gas reservoir in China and its scientific value[J]. Acta Petrologica Sinica, 27(6):1857-1864. (in Chinese with English abstract) http://cn.bing.com/academic/profile?id=eb9a55540c2dd5a747e0a229783f1024&encoded=0&v=paper_preview&mkt=zh-cn 白斌, 朱如凯, 吴松涛, 等, 2013.利用多尺度CT成像表征致密砂岩微观孔喉结构[J].石油勘探与开发, 40(3):329-333. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=syktykf201303009 冯胜斌, 牛小兵, 刘飞, 等, 2012.鄂尔多斯盆地长7致密油储层储集空间特征及其意义探讨[J].中南大学学报(自然科学版), 44(11):4574-4580. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=QKV20122013050600038100 冯渊, 杨伟伟, 刘一仓, 等, 2015.鄂尔多斯盆地镇北油田长81油藏电阻率差异成因[J].新疆石油地质, 36(5):526-530. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=xjsydz201505005 郝乐伟, 王琪, 唐俊, 2013.储层岩石微观孔隙结构研究方法与理论综述[J].岩性油气藏, 25(5):123-128. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=yxyqc201305023 何涛, 王芳, 汪伶俐, 2013.致密砂岩储层微观孔隙结构特征:以鄂尔多斯盆地延长组长7储层为例[J].岩性油气藏, 25(4):23-26. 李海燕, 岳大力, 张秀娟, 2012.苏里格气田低渗透储层微观孔隙结构特征及其分类评价方法[J].地学前缘, 19(2):133-140. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=dxqy201202019 李静, 孔祥超, 宋明水, 等, 2019.储层岩石微观孔隙结构对岩石力学特性及裂缝扩展影响研究[J].岩土力学, 40(11):4149-4156, 4164. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=ytlx201911004 李易霖, 张云峰, 丛琳, 等, 2016. X-CT扫描成像技术在致密砂岩微观孔隙结构表征中的应用:以大安油田扶余油层为例[J].吉林大学学报(地球科学版), 46(2):379-387. 李竹林, 王明芳, 呼建雪, 等, 2015.医学图像增强算法与特征提取算法研究与实现[J].计算机技术与发展, 25(1):115-118. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=wjfz201501026 林承焰, 吴玉其, 任丽华, 等, 2018.数字岩心建模方法研究现状及展望[J].地球物理学进展, 33(2):679-689. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=dqwlxjz201802030 刘承婷, 曲晗, 刘保君, 2011.低渗透储层微观结构特征研究[J].科学技术与工程, 11(21):5002-5004. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=kxjsygc201121010 刘惠民, 郑金凯, 赵文山, 等, 2019.深层致密砂岩储层脆性指数评价新方法[J].地质力学学报, 25(4):492-500. http://journal.geomech.ac.cn/ch/reader/view_abstract.aspx?flag=1&file_no=20190406&journal_id=dzlxxb 刘学锋, 张伟伟, 孙建孟, 2013.三维数字岩心建模方法综述[J].地球物理学进展, 28(6):3066-3072. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=dqwlxjz201306030 刘向君, 朱洪林, 梁利喜, 2014.基于微CT技术的砂岩数字岩石物理实验[J].地球物理学报, 57(4):1133-1140. http://www.cnki.com.cn/Article/CJFDTotal-DQWX201404011.htm 罗顺社, 魏炜, 魏新善, 等, 2013.致密砂岩储层微观结构表征及发展趋势[J].石油天然气学报, 35(9):5-10. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=jhsyxyxb201309002 罗蛰潭, 王允诚, 1986.油气储集层的孔隙结构[M].北京:科学出版社. 毛慧华, 王枫红, 陈炽坤, 等, 2012.几种常用CT图像分割算法分析和探讨[J].计算机与数字工程, 40(1):101-103, 108. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=jsjyszgc201201034 佘敏, 寿建峰, 郑兴平, 等, 2011.基于CT成像的三维高精度储集层表征技术及应用[J].新疆石油地质, 32(6):664-666. http://www.cnki.com.cn/Article/CJFDTotal-XJSD201106029.htm 王家禄, 高建, 刘莉, 2009.应用CT技术研究岩石孔隙变化特征[J].石油学报, 30(6):887-893, 897. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=syxb200906015 杨正明, 姜汉桥, 李树铁, 等, 2007.低渗气藏微观孔隙结构特征参数研究:以苏里格和迪那低渗气藏为例[J].石油天然气学报, 29(6):108-110, 119. 姚军, 赵秀才, 衣艳静, 等, 2005.数字岩心技术现状及展望[J].油气地质与采收率, 12(6):52-54. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=yqdzycsl200506017 姚军, 赵秀才, 2010.数字岩心及孔隙级渗流模拟理论[M].北京:石油工业出版社. 尤源, 牛小兵, 冯胜斌, 等, 2014.鄂尔多斯盆地延长组长7致密油储层微观孔隙特征研究[J].中国石油大学学报(自然科学版), 38(6):18-23. http://www.cqvip.com/QK/91985A/201406/662853727.html 尤源, 牛小兵, 李廷艳, 等, 2016. CT技术在致密砂岩微观孔隙结构研究中的应用:以鄂尔多斯盆地延长组长7段为例[J].新疆石油地质, 37(2):227-230. http://www.cqvip.com/QK/93464X/201602/668488701.html 张巍, 贺星, 霍颖翔, 等, 2013.基于并行运算的双层图像锐化方法[J].计算机应用, 33(8):2325-2329. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=jsjyy201308057 赵秀才, 姚军, 2007.数字岩心建模及其准确性评价[J].西安石油大学学报(自然科学版), 22(2):16-20. http://www.cqvip.com/Main/Detail.aspx?id=24281829 周尚文, 薛华庆, 郭伟, 2017.基于扫描电镜和X射线能谱的页岩矿物分析方法[J].中国石油勘探, 22(6):27-33. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgsykt201706004 朱益华, 陶果, 2007.顺序指示模拟技术及其在3D数字岩心建模中的应用[J].测井技术, 31(2):112-115. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=cjjs200702005 邹才能, 朱如凯, 白斌, 等, 2011.中国油气储层中纳米孔首次发现及其科学价值[J].岩石学报, 27(6):1857-1864. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=ysxb98201106024 -
下载:
图(14)
计量
- 文章访问数: 476
- HTML全文浏览量: 103
- PDF下载量: 16
- 被引次数: 0
