Quantitative evaluation of the influence of siderite cements on middle-shallow reservoirs: A case study of the southern oil area in the Enping Sag, Pearl River Mouth Basin
-
摘要:
为了厘清菱铁矿胶结物的成因,研究菱铁矿胶结物对储层的影响及其储层地质模式,探讨含菱铁矿的储层对于油田开发生产的影响,开展菱铁矿胶结物成因及对物性的影响研究。基于常规岩心、薄片鉴定、X衍射等资料,对珠江口盆地恩平油区中浅储层胶结物类型及特征统计发现,该区菱铁矿胶结物富集。通过古海洋氧化还原状态和沉积环境研究了其成因机制,并定量研究了菱铁矿对储集层质量的影响。结果表明:研究区储层中菱铁矿是成岩作用过程中由有机质降解产生的CO2与孔隙水中富集的Fe2+结合的产物,形成于砂岩原生孔隙发育的早成岩期,对储层整体孔隙的保存具有积极意义;但菱铁矿胶结的局部(多发育于薄层泥质条带中),由于其占据了较大比例的原生孔隙空间,对储层具有较大破坏性。菱铁矿胶结物的"控渗"作用使泥质条带处纵向渗透率远远低于其他方向渗透率,从而大大增加了泥质薄层对底水的遮挡效果。研究成果在B油田进行应用时发现,富菱铁矿胶结物含水平条带状夹层导致高部位出现能量供给不足,通过"自源闭式助流注热水"用以增能,促使油田产量翻番,大幅提高油藏采出程度。
Abstract:In order to clarify the cause of formation of siderite cement, and study the influence of siderite cement on reservoir and its geological model, and explore the influence of siderite-bearing reservoir on oilfield development and production, the study of the cause of formation of siderite cement and its influence on physical properties was carried out. Based on conventional core analysis, thin section analysis and X-ray analysis, statistics on the types and characteristics of cements in middle-shallow reservoirs in the Enping oil area, Pearl River Mouth Basin, reveal that siderite cement is abundant. The redox state and sedimentary environment of the paleo-ocean were used to study the genetic mechanism of siderite and quantitatively study the influence of siderite on middle-shallow reservoir quality. The results show that siderite in the reservoir is the product of the combination of CO2 produced by the degradation of organic matter and Fe2+ enriched in pore water during diagenesis. It formed in the early diagenetic stage when the primary pores of sandstone developed, which has a positive significance for the preservation of the overall pores of the reservoir. However, the local cementation of siderite (mostly developed in thin argillaceous belts) is destructive to the reservoir because it occupies a large proportion of the primary pore space. The "permeability control" effect of siderite cement makes the vertical permeability of the muddy strip much lower than that in other directions, thus greatly increasing the shielding effect of the muddy thin layer on the bottom water, which is conducive to reservoir development. Due to the blocking of argillaceous belts, the reservoir geological pattern will change from bottom water reservoir to edge water reservoir and edge water reservoir to multilayer edge water reservoir, which can be exploited by corresponding development measures. The development of siderite leads to differences in the energy supply in the top, middle and edge of the reservoir, which can guide water injection and improve the well pattern strategy. The research results were applied in Oilfield B, where the horizontal strip interlayer of fulling siderite cements resulted in insufficient energy supply in the high position. By injecting hot water to increase energy, oil field production is doubled, and reservoir recovery is greatly improved.
-
Key words:
- Pearl River Mouth Basin /
- Enping oil area /
- middle-shallow reservoir /
- siderite /
- cement /
- permeability /
- argillaceous thin layer
-
-
[1] 王兴志, 方少仙, 侯方浩, 等. 四川盆地灯影组储层原生孔隙内胶结物研究[J]. 西南石油学院学报, 1998, 20(3): 1-6. https://www.cnki.com.cn/Article/CJFDTOTAL-XNSY803.000.htmWang X Z, Fang S X, Hou F H, et al. A study of the cement in primary pores in carbonate reservoirs of Dengying Formation, Sichuan Basin[J]. Journal of Southwest Petroleum Institute, 1998, 20(3): 1-6(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-XNSY803.000.htm [2] 邹海峰, 高福红, 徐学纯, 等. 大港探区中区下第三系砂岩碳酸盐岩胶结物与填隙物的成因机理[J]. 吉林大学学报: 地球科学版, 2002, 32(1): 34-38. https://www.cnki.com.cn/Article/CJFDTOTAL-CCDZ200201008.htmZou H F, Gao F H, Xu X C, et al. Geochemistry study on the forming mechanism of the cement of Dagang exploration area[J]. Journal of Jilin University: Earth Science Edition, 2002, 32(1): 34-38(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-CCDZ200201008.htm [3] 柳娜, 南珺祥, 刘伟, 等. 鄂尔多斯盆地西部长8储层胶结物特征[J]. 复杂油气藏, 2015, 8(1): 15-19, 33. https://www.cnki.com.cn/Article/CJFDTOTAL-FZYQ201501004.htmLiu N, Nan J X, Liu W, et al. Characteristics of the cements in Chang 8 reservior in western Ordos Basin[J]. Complex Hydrocarbon Reserviors, 2015, 8(1): 15-19, 33(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-FZYQ201501004.htm [4] 陈成业, 王钦贤, 陈多福. 台湾国姓地区中新世海相菱铁矿的成因[J]. 沉积学报, 2022, 40(6): 1691-1701. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB202206016.htmChen C Y, Wang Q X, Chen D F. Genesis of siderite in miocene marine shale in Kuohsing area, Taiwan[J]. Acta Sedimentologica Sinica, 2022, 40(6): 1691-1701(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB202206016.htm [5] 王清斌, 臧春艳, 赖维成, 等. 渤中坳陷古近系中、深部碎屑岩储层碳酸盐胶结物分布特征及成因机制[J]. 石油与天然气地质, 2009, 30(4): 438-443. https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT200904012.htmWang Q B, Zang C Y, Lai W C, et al. Distribution characteristics and origin of carbonate cements in the middle and deep clastic reservoirs of the Paleogene in the Bozhong Depression[J]. Oil & Gas Geology, 2009, 30(4): 438-443(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-SYYT200904012.htm [6] 肖晓光, 秦兰芝, 张武, 等. 西湖凹陷平湖组碳酸盐胶结物形成机制及其对储层的影响[J]. 地质科学, 2021, 56(4): 1062-1076. https://www.cnki.com.cn/Article/CJFDTOTAL-DZKX202104005.htmXiao X G, Qin L Z, Zhang W, et al. The origin of carbonate cements and the influence on reservoir quality of Pinghu Formation in Xihu Sag[J]. Chinese Journal of Geology, 2021, 56(4): 1062-1076(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-DZKX202104005.htm [7] 王晔桐, 孙国强, 张顺存, 等. 柴北缘腹部砂岩中碳酸盐胶结物特征及成因探讨[J]. 天然气地球科学, 2021, 32(7): 1037-1046. https://www.cnki.com.cn/Article/CJFDTOTAL-TDKX202107010.htmWang Y T, Sun G Q, Zhang S C, et al. Characteristics and genesis of carbonate cement in abdomen sandstone in northern margin of Qaidam Basin[J]. Natural Gas Geoscience, 2021, 32(7): 1037-1046(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-TDKX202107010.htm [8] 杜贵超, 苏龙, 陈国俊, 等. 番禺低隆起珠海组砂岩碳酸盐胶结特征及其对储层物性的影响[J]. 岩性油气藏, 2019, 31(3): 10-19. https://www.cnki.com.cn/Article/CJFDTOTAL-YANX201903002.htmDu G C, Su L, Chen G J, et al. Carbonate cements and its effect on reservoir property of shallow marine sandstones of Zhuhai Formation in Panyu low-uplift, Pearl River Mouth Basin[J]. Lithologic Reservoirs, 2019, 31(3): 10-19(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-YANX201903002.htm [9] 姜平, 王珍珍, 邹明生, 等. 文昌A凹陷珠海组砂岩碳酸盐胶结物发育特征及其对储层质量的影响[J]. 地球科学, 2021, 46(2): 600-620. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX202102015.htmJiang P, Wang Z Z, Zou M S, et al. Development characteristics of carbonate cement and its influence on reservoir quality in sandstones from Zhuhai Formation in Wenchang A Depression[J]. Earth Science, 2021, 46(2): 600-620(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX202102015.htm [10] 刘丽华, 陈胜红, 于水明, 等. 恩平凹陷成藏条件分析及商业性突破[J]. 中国海上油气, 2011, 23(2): 76-80. https://www.cnki.com.cn/Article/CJFDTOTAL-ZHSD201102001.htmLiu L H, Chen S H, Yu S M, et al. Analysis conditions of hydrocarbon accumulation and a commercial breakthrough in Enping Sag, Pearl River Mouth Basin[J]. China Offshore Oil and Gas, 2011, 23(2): 76-80(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-ZHSD201102001.htm [11] 傅宁, 丁放, 何仕斌, 等. 珠江口盆地恩平凹陷烃源岩评价及油气成藏特征分析[J]. 中国海上油气, 2007, 19(5): 295-299, 305. https://www.cnki.com.cn/Article/CJFDTOTAL-ZHSD200705003.htmFu N, Ding F, He S B, et al. Source rocks evaluation and reservoir characteristics analysis in Enping Sag, Pear River Mouth Basin[J]. China Offshore Oil and Gas, 2007, 19(5): 295-299, 305(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-ZHSD200705003.htm [12] 李林, 罗东红, 陶彬, 等. 番禺油田薄层边底水稠油油藏水平井含水率上升特征[J]. 石油地质与采收率, 2016, 3(23): 106-110. https://www.cnki.com.cn/Article/CJFDTOTAL-YQCS201603019.htmLi L, Luo D H, Tao B, et al. Water cut rising performance of horizontal wells in thin-bed heavy oil reservoir with edge-bottom water in Panyu Oilfield[J]. Petroleum Geology and Recovery Efficiency, 2016, 3(23): 106-110(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-YQCS201603019.htm [13] 曾勇. 内蒙古准格尔旗晚石炭世-早二叠世早期腕足类物种多样性与沉积环境[J]. 古地理学报, 2007, 9(5): 513-518. https://www.cnki.com.cn/Article/CJFDTOTAL-GDLX200705011.htmZeng Y. Brachiopod diversity and sedimentary environments of the Late Carboniferous and early Early Permian in Jungar, Inner Mongolia[J]. Journal of Palaeogeography, 2007, 9(5): 513-518(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-GDLX200705011.htm [14] 张衎, 朱祥坤. 蓟县下马岭组菱铁矿的成因及古海洋意义[J]. 地质学报, 2013, 87(9): 1430-1438. https://www.cnki.com.cn/Article/CJFDTOTAL-DZXE201309019.htmZhang K, Zhu X K. Genesis of siderites in the Xiamaling Formation of Jixian section and its paleoceanic significance[J]. Acta Geologica Sinica, 2013, 87(9): 1430-1438(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-DZXE201309019.htm [15] 刘敏, 陈志明, 陈其英. 有机质在宣龙地区菱铁矿形成中的作用[J]. 沉积学报, 1997, 15(3): 96-102. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB703.017.htmLiu M, Chen Z M, Chen Q Y. The role of organic matter in the genesis of siderite from the Xuanlong area[J]. Acta Sedimentologica Sinica, 1997, 15(3): 96-102(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB703.017.htm [16] 康昱, 陈刚, 张卫刚, 等. 鄂尔多斯盆地姬塬油区铁边城区块长8储层成岩致密化及其与油气成藏关系[J]. 地质科技通报, 2021, 40(2): 64-75. doi: 10.19509/j.cnki.dzkq.2021.0207Kang Y, Chen G, Zhang W G, et al. Diagenetic densification of Chang 8 sandstone reservoirs and its relationship with hydrocarbon accumulation in Tiebiancheng area, Jiyuan Oilfield, Ordos Basin[J]. Bulletin of Geological Science and Technology, 2021, 40(2): 64-75(in Chinese with English abstract). doi: 10.19509/j.cnki.dzkq.2021.0207 [17] Kaufman A J, Knoll A H. Neoproterozoic variations in the C-isotopic composition of seawater: Stratigraphic and biogeochemical implications[J]. Precambrian Research, 1995, 73(1/2/3/4): 27-49. [18] 姚佳, 王昕, 王清斌, 等. 黄河口凹陷BZ34区古近系沙一二段储集层成岩相与有利储层预测[J]. 现代地质, 2016, 30(6): 1339-1347. https://www.cnki.com.cn/Article/CJFDTOTAL-XDDZ201606017.htmYao J, Wang X, Wang Q B, et al. Reservoir diagenetic facies and favorable reservoir prediction of the Member 1 and 2 of Palaeogene Shahejie Formation in BZ34 area of Huanghekou Depression[J]. Geoscience, 2016, 30(6): 1339-1347(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-XDDZ201606017.htm [19] 邹明亮, 黄思静, 胡作维, 等. 西湖凹陷平湖组砂岩中碳酸盐胶结物形成机制及其对储层质量的影响[J]. 岩性油气藏, 2008, 20(1): 47-52.Zou M L, Huang S J, Hu Z W, et al. The origin of carbonate cements and the influence on reservoir quality of Pinghu Formation in Xihu Sag, East China Sea[J]. Lithologic Reservoirs, 2008, 20(1): 47-52(in Chinese with English abstract). [20] 桑树勋, 郑永飞, 张华, 等. 徐州地区下古生界碳酸盐岩的碳、氧同位素研究[J]. 岩石学报, 2004, 20(3): 707-716. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200403035.htmSang S X, Zheng Y F, Zhang H, et al. Researches on carbon and oxygen stable isotopes of Lower Paleozoic carbonates in Xuzhou area[J]. Acta Petrologica Sinica, 2004, 20(3): 707-716(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200403035.htm [21] 李智, 叶加仁, 曹强, 等. 鄂尔多斯盆地杭锦旗独贵加汗区带下石盒子组储层特征及孔隙演化[J]. 地质科技通报, 2021, 40(4): 49-60. doi: 10.19509/j.cnki.dzkq.2021.0404Li Z, Ye J R, Cao Q, et al. Reservior characteristics and pore evolution of the Lower Shihezi Formation in Duguijiahan zone, Hangjinqi area, Ordos Basin[J]. Bulletin of Geological Science and Technology, 2021, 40(4): 49-60(in Chinese with English abstract). doi: 10.19509/j.cnki.dzkq.2021.0404 [22] 朱义东, 戴建文, 王亚会, 等. 基于不同地质模式下稠油油藏变速驱波及规律实验研究[J]. 地质科技通报, 2022, 41(3): 68-76. doi: 10.19509/j.cnki.dzkq.2021.0048Zhu Y D, Dai J W, Wang Y H, et al. Experimental study on sweep pattern of heavy oil reservoir with variable speed drive based on different geological models[J]. Bulletin of Geological Science and Technology, 2022, 41(3): 68-76(in Chinese with English abstract). doi: 10.19509/j.cnki.dzkq.2021.0048