Calculation method of variation function for predicting sandstone-type uranium ore bady by geostatistical inversion
WEI Da1, SUN Zhangqing2
1. E & D Research Institute, Liaohe Oilfield of CNPC, Panjin, Liaoning 124010, China; 2. College of Geoexploration Science and Techno-logy, Jilin University, Changchun, Jilin 130026, China
Abstract:The reliability of geostatistical inversion is mainly controlled by the selection of key parameters such as the variation function. The traditional method of calculating the transverse range of the variation function has high randomness. To improve the accuracy of geostatistical inversion in predicting sandstone-type uranium ore body, this paper proposed a method of calculating the variation function under the control of logging data and geological significance. In this method, the vertical range is calculated by counting the data points in the well. The transverse range is calculated through statistics and analysis of the ore body scales and ore-bearing properties of ore occurrences in a developed zone. Compared with conventional deterministic inversion, geostatistical inversion, based on random modeling of logging data, not only retains the high transverse resolution of seismic data but also displays higher vertical resolution. It has a good prediction effect in the Qianjiadian (QJD) sandstone-type uranium ore body with a small thickness and rapid transverse changes. Here, the calculation of the variation function is an important factor affecting the inversion result. The prediction accuracy analysis of the QJD uranium ore body and practical application in the study area conclude as follows:① When the vertical range is 4.5 m, the vertical resolution of the inversion result is the highest, and the inversion efficiency is high; ② Compared with post-stack sparse pulse inversion, the results of geostatistical inversion based on the proposed calculation method of the variation function are more consistent with the actual ore body distribution; ③ The discovery rate of industrial ore in 12 exploration wells deployed according to the inversion results obtained by the proposed method is 75%, and the average exploration success rate is greatly improved.
陈戴生, 李胜祥, 蔡煜琦.我国中新生代盆地砂岩型铀矿研究现状及发展方向的探讨[J]. 沉积学报, 2003, 21(1):113-117.CHEN Daisheng, LI Shengxiang, CAI Yuqi.A dis-cussion on research situation and developmental direction of sandstone-type uranium deposit in the Meso-Cenozoic basins in China[J]. Acta Sedimentologica, 2003, 21(1):113-117.
[2]
陈祖伊.亚洲砂岩型铀矿区域分布规律和中国砂岩型铀矿找矿对策[J]. 铀矿地质, 2002, 18(3):129-137.CHEN Zuyi.Regional distribution regularity of sandstone uranium deposits in Asian continent and prospecting strategy for sandstone uranium deposits in China[J]. Uranium Geology, 2002, 18(3):129-137.
[3]
夏毓亮, 林锦荣, 李子颖, 等.松辽盆地钱家店凹陷砂岩型铀矿预测评价和铀成矿规律研究[R].中国核科技报告, 2003, 105-117.XIA Yuliang, LIN Jinrong, LI Ziying, et al. Perspective and Resource Evaluation and Metallogenic Studies on Sandstone-type Uranium Deposit in Qianjiadian Depression of Songliao Basin[R].China Nuclear Science Progress Report, 2003, 105-117.
徐国苍, 张红建, 朱琳.浅层地震勘探在砂岩型铀矿勘查中的应用研究[J]. 铀矿地质, 2013, 29(1):37-46.XU Guocang, ZHANG Hongjian, ZHU Lin.Application of shallow seismic exploration method in the prospecting for in-situ leachable sandstone-type uranium deposits[J]. Uranium Geology, 2013, 29(1):37-46.
[6]
吴曲波, 李子伟, 潘自强, 等.砂岩型铀矿地震勘探中若干问题研究[J]. 地球物理学进展, 2017, 32(5):2097-2106.WU Qubo, LI Ziwei, PAN Ziqiang, et al.Study on some problems in the seismic exploration of sandstone type uranium deposits[J]. Progress in Geophysics, 2017, 32(5):2097-2106.
[7]
李子伟, 陈敬国, 吴曲波, 等.地震勘探方法在伊犁盆地南缘砂岩型铀矿勘查中的应用研究[J]. 铀矿地质, 2016, 32(4):235-241, 250.LI Ziwei, CHEN Jingguo, WU Qubo, et al. Application of seismic method in the exploration of sandstone type uranium deposit in the southern margin of Yili Basin[J]. Uranium Geology, 2016, 32(4):235-241, 250.
Haas A, Dubrule O.Geostatistical inversion:A sequential method of stochastic reservoir modeling constrained by seismic data[J]. First Break, 1994, 12(11):561-569.
[11]
Dubrule O, Thibaut M, Lamy P, et al. Geostatistical reservoir characterization constrained by 3D seismic data[J]. Petroleum Gesocience, 1998, 4(2):121-128.
[12]
范廷恩, 马良涛, 胡光义, 等.基于层序地层学的地质统计学反演[J]. 地球物理学进展, 2019, 34(1):80-89.FAN Ting'en, MA Liangtao, HU Guangyi, et al.Geostatistical inversion based on sequence stratigraphy[J]. Progress in Geophysics, 2019, 34(1):80-89.
[13]
韩东, 胡向阳, 邬兴威, 等.基于地质统计学反演的缝洞储集体物性定量评价[J]. 地球物理学进展, 2016, 31(2):655-661.HAN Dong, HU Xiangyang, WU Xingwei, et al. Quantitative evaluation for porosity of the fracture-cavity reservoir based on geostatistical inversion[J]. Progress in Geophysics, 2016, 31(2):655-661.
[14]
尚建林, 李太辉, 霍新勇, 等.地质统计学反演预测百口泉油田百34井区薄砂体[J]. 新疆石油地质, 2009, 30(6):758-760.SHANG Jianlin, LI Taihui, HUO Xinyong, et al. App-lication of geostatistical inversion to prediction of thin sand body of Karamay formation in Bai-34 well area in Baikouquan oil field[J]. Xingjiang Petroleum Geology, 2009, 30(6):758-760.
[15]
宁松华, 曹淼, 刘雷颂, 等.地质统计学反演在三道桥工区储层预测中的应用[J]. 石油天然气学报, 2014, 36(7):52-54.NING Songhua, CAO Miao, LIU Leisong, et al.App-lication of geostatistical inversion method in reservior prediction of Sandaogiao area[J]. Journal of Oil and Gas Technology, 2014, 36(7):52-54.
[16]
王雅春, 王璐.地质统计学反演在杏北西斜坡区储层预测中的应用[J]. 地球物理学进展, 2013, 28(5):2554-2560.WANG Yachun, WANG Lu.Application of geostatistical inversion to reservoir prediction in the Western Slope of the northern Xingshugang oil field[J]. Progress in Geophysics, 2013, 28(5):2554-2560.
[17]
慎国强, 孟宪军, 王玉梅, 等.随机地震反演方法及其在埕北35井区的应用[J]. 石油地球物理勘探, 2004, 39(1):75-81.SHEN Guoqiang, MENG Xianjun, WANG Yumei, et al. Random seismic inversion and its application in Chengbei No.35 well-zone[J]. Oil Geophysical Prospecting, 2004, 39(1):75-81.
[18]
易平, 林桂康.随机地震反演技术及在文昌13-1油田的应用[J]. 石油地球物理勘探, 2005, 40(1):87-91.YI Ping, LIN Guikang.Seismic stochastic inversion and its application in Wenchang 13-1 oilfield[J]. Oil Geophysical Prospecting, 2005, 40(1):87-91.
[19]
孙思敏, 彭仕宓.地质统计学反演方法及其在薄层砂体预测中的应用[J]. 西安石油大学学报(自然科学版), 2007, 22(1):41-44, 48.SUN Simin, PENG Shibi. Geostatistical inversion method and its application in the prediction of thin reservoirs[J]. Journal of Xi'an Shiyou University(Na-tural Science Edition), 2007, 22(1):41-44, 48.
[20]
王晓平, 尚建林, 王林生, 等.地质统计反演在准噶尔盆地玛北油田的应用[J]. 新疆石油地质, 2013, 34(3):320-323.WANG Xiaoping, SHANG Jianlin, WANG Linsheng, et al. Application of geostatistic inversion technology to Mabei oilfield in Junggar Basin[J]. Xinjiang Petroleum Geology, 2013, 34(3):320-323.
[21]
罗林.地质统计学反演在钱家店地区砂岩型铀矿勘探中的应用[J]. 铀矿冶, 2018, 37(1):68-72.LUO Lin.Application of geostatistical inversion for exploration of sandstone type uranium ore in Qianjiadian area[J]. Uranium Mining and Metallurgy, 2018, 37(1):68-72.
[22]
董奇, 卢双舫, 张学娟, 等.地质统计学反演参数选取及反演结果可靠性分析[J]. 物探与化探, 2013, 37(2):328-332, 337.DONG Qi, LU Shuangfang, ZHANG Xuejuan, et al. Selection of parameters and reliability analysis of results in geostatistical inversion method[J]. Geophysical & Geochemical Exploration, 2013, 37(2):328-332, 337.
[23]
刘兴冬.随机反演变差函数适用性研究[J]. 石油天然气学报, 2010, 32(2):253-256.LIU Xingdong.Adaptability for variation function in random inversion[J]. Journal of Oil and Gas Techno-logy, 2010, 32(2):253-256.
[24]
秦月霜, 郭海晓, 陈友福.变差函数对地震反演精度的影响[J]. 大庆石油学院学报, 2009, 33(5):37-40.QIN Yueshuang, GUO Haixiao, CHEN Youfu.Effect of variogram on seismic inversion accuracy[J]. Journal of Daqing Petroleum Institute, 2009, 33(5):37-40.
[25]
樊鹏军, 马良涛, 王宗俊, 等.地质统计学反演中变差函数地质含义及求取方法探讨[J]. 地球物理学进展, 2017, 32(6):2444-2450.FAN Pengjun, MA Liangtao, WANG Zongjun, et al.Variogram geological implication and its calculating method discussing for geostatistical inversion[J]. Progress in Geophysics, 2017, 32(6):2444-2450.