Study on the difference of water-bearing capacity of fault-controlled dolomites in Dengying Formation of a mining area in central Guizhou and its significance of water control
-
摘要: 黔中地区矿床水文地质条件复杂,磷矿的主要充水层灯影组富水性中等至强,矿坑突水严重影响区域磷矿资源的安全开采。因此,掌握该区域灯影组的富水性特征极为重要。文章依托贵州省2020年矿产资源大精查项目资料,采用研究与生产相结合、典型矿区解剖的方法开展该矿床灯影组富水性研究。结果表明:黔中地区大湾磷矿为顶板直接充水的岩溶矿床,充水层灯影组的岩性、结构以及断裂构造是控制矿床充水条件的主要因素,灯影组含水性和透水性具有明显的“平面分块”和“垂向分层”的分布规律。充分利用该特征对于矿井防水设计并指导矿山开采,对保障黔中磷矿安全生产、降低开采成本具有重要意义。Abstract: The central region of Guizhou Province enjoys global fame of its areas with large-scale production rich in phosphorus. For a long time, the phosphate rock resources in this area have provided a reliable guarantee for the domestic economic development. At present, this region has also become an important raw material base of phosphate rocks and a production base of fine phosphate chemicals in China. After decades of mining, phosphorus mines in this area have gradually changed from open pits to underground ones and from shallow to deep, and thus the hydrogeological conditions of deposits become increasingly complex. Dengying Formation, the main aquifers of phosphate rocks, is composed of dolomite with the water-bearing medium of solution pores and cracks. It is a water-bearing formation comprised of pure carbonate rocks with medium to high water abundance. Consequently, the high cost of mine drainage has imposed a heavy burden on mining enterprises. In addition, mine water inrush has severely threatened the exploitation safety of phosphate rock resources in this region. Therefore, it is very important to research the characteristics of water abundance of the Dengying Formation. The phosphate mine of Dawan, a water-filling deposit with deeply covered karst, is located on the western flank of the Baiyan anticline. The high bearing capacity of groundwater and complicated hydrogeological conditions of Dengying Formation are representative and typical in the Baiyan anticline area. Due to the super large scale and high grade of phosphate ore resources, the phosphate mine of Dawan was listed as a key project of mineral resource exploration in Guizhou Province in 2020. During the exploration work, a large amount of geological data was obtained through surface surveys, geophysical and hydrological logging, drilling, and hydrogeological experiments. In this paper, a study on the water abundance of the Dengying Formation of the deposit has been conducted based on the data from the exploration of the phosphate mine as well as the anatomy of typical mining areas. The research results show that the phosphate mine in Dawan is a karst deposit with water-filled roof, and the lithology, structure and fracture structure of the Dengying Formation in the water-filled layer are the main factors controlling the water-filling condition of the deposit. With an obvious distribution law, the water content and permeability of Dengying Formation present obvious characteristics of "plane partition" and "vertical stratification". In the plane of exploration area, there is a significant difference in water abundance of the Dengying Formation near and far from the structural area. The differences in fault properties also result in different water abundance of the Dengying Formation. In the vertical direction, there is a weak permeable layer with poor water content and relative water resistance in the middle and lower parts of the Dengying Formation. The waterproof design of mine based on the characteristics of water abundance in Dengying Formation is of great significance to ensure the safe production of the phosphate mine in central Guizhou, and to reduce the cost of mining drainage.
-
图 1 区域水文地质图
1-碳酸盐岩含水岩组,富水性中等至强 2-碳酸盐岩夹碎屑岩含水岩组,富水性中等 3-基岩裂隙水含水岩组,富水性弱 4-三叠系嘉陵江组 5-夜郎组 6-二叠系吴家坪组 7-栖霞茅口组 8-寒武系娄山关组 9-石冷水高台组 10-清虚洞组 11-金顶山至牛蹄塘组 12-震旦系灯影组至陡山沱组 13-南华系南陀组 14-背斜 15-断层 16-地质界线 17-地层产状 18-灯影组地下水流向 19-水文地质单元界线 20-地表河流 21-矿区范围 22-剖面线 23-乡镇 24-村寨
Figure 1. Regional hydrogeological map
1. water-bearing formation comprised of carbonate rocks with medium to high water abundance 2. water-bearing formation comprised of carbonate rocks with clastic rock, water abundance is medium 3. water-bearing formation comprised of bedrock fissure water with low water abundance 4. Jialingjiang Formation of Triassic System 5. Yelang Formation 6. Wujiaping Formation of Permian System 7. Qixia Maokou Formation 8. Cambrian Loushanguan Formation 9. Shilengshui and Gaotai Formation 10. Qingxudong Formation 11. Jindingshan to Niutitang Formation 12. Sinian Dengying Formation to Doushantuo Formaiton 13. Nanhuan System Nantuo Formaiton 14. anticline 15. fault 16. Geological boundary 17. attitude of stratum 18. groundwater flow direction of Dengying Formation 19. hydrogeological unit boundary 20. surface river 21. mine field 22. section line 23. township 24. village
图 2 A-A′水文地质剖面图
1-碳酸盐岩含水岩组,富水性中等至强 2-基岩裂隙水含水岩组,富水性弱 3-地层代号 4-灰岩 5-白云岩6-含磷白云岩 7-泥质白云岩 8-泥岩 9-泥质粉砂岩 10-炭质泥岩 11-冰碛砾岩 12-断层及编号
Figure 2. A-A′ hydrogeological section
1. water-bearing formation comprised of carbonate rocks with medium to high water abundance 2. water-bearing formation comprised of bedrock fissure water with low water abundance 3. stratigraphic code 4. limestone 5. dolomite 6. phosphorous dolomite 7. argillaceous dolomite 8. mud rock 9. argillaceous siltstone 10. carbon mudstone 11. moraine conglomerate 12. fault and numbering
图 3 研究区工程平面布置图
1-抽水试验钻孔 2-多孔抽水试验观测孔 3-测井钻孔 4-断层 5-地层代号及界线 6-剖面线7-河流 8-先期开采范围 9-矿区界线
Figure 3. Plan of the project in the study area
1-pumping test borehole 2-porous pumping test observation hole 3-logging hole 4-fault 5-stratigraphic code and boundary 6-section line 7-river 8-initial mining area 9-mine boundary
图 4 9线水文地质剖面图
1-碳酸盐岩含水岩组,富水性中等至强 2-碳酸盐岩含水岩组,富水性弱 3-基岩裂隙水含水岩组,富水性弱 4-孔隙水,富水性弱 5-地层代号 6-断层 7-钻孔 8-剖面方位
Figure 4. Hydrogeological section of Line No. 9
1. water-bearing formation comprised of carbonate rocks with medium to high water abundance 2. water-bearing formation comprised of carbonate rocks with low water abundance 3. water-bearing formation comprised of bedrock fissure water with low water abundance 4. pore water with low water abundance 5. stratigraphic code 6. fault 7.borehole 8. profile azimuth
图 5 水文试验孔与断层位置剖面示意图
1-碳酸盐岩含水岩组,富水性中等至强 2-碳酸盐岩含水岩组,富水性弱 3-基岩裂隙水含水岩组,富水性弱 4-孔隙水,富水贫乏 5-地层代号 6-灯影组分段编号 7-断层 8-钻孔 9-剖面方位
Figure 5. Sections of the hydrologic test hole and the fault position
1. water-bearing formation comprised of carbonate rocks with medium to high water abundance 2. water-bearing formation comprised of carbonate rocks with low water abundance 3. water-bearing formation comprised of bedrock fissure water with low water abundance 4. pore water with poor water abundance 5. stratigraphic code 6. Dengying Formation section numbering 7. fault 8. borehole 9. profile azimuth
图 6 灯影组走向上含水段划分图
1-碳酸盐岩含水岩组,富水性中等至强 2-碳酸盐岩含水岩组,富水性弱 3-基岩裂隙水含水岩组,富水性弱4-孔隙水,富水贫乏 5-测井显示含水段 6-地层代号 7-断层 8-钻孔 9-剖面方位
Figure 6. Division of aquifer sections along the Dengying Formation
1. water-bearing formation comprised of carbonate rocks with medium to high water abundance 2. water-bearing formation comprised of carbonate rocks with low water abundance 3. water-bearing formation comprised of bedrock fissure water with low water abundance 4. pore water with poor water abundance 5. water-bearing section while logging 6. stratigraphic code 7. fault 8. borehold 9. profile azimuth
表 1 灯影组中下部弱含水层统计表
Table 1. Statistics of weak permeable layers in the middle and lower parts of the Dengying Formation
钻孔编号 弱含水段埋深位置/m 厚度值/m 备注 ZK601 542.50~591.00 48.50 ZK602 501.76~625.60 123.84 ZK710 386.00~428.68 42.68 ZK711 533.36~655.00 121.64 ZK712 606.89~665.80 58.91 ZK906 519.01~562.00 42.99 ZK909 524.75~564.68 39.93 ZK1111 444.48~521.50 77.02 ZK1305 520.69~620.80 100.11 表 2 灯影组分层抽水试验参数表
Table 2. Parameters of the stratified pumping test of the Dengying Formation
孔号 抽水段 降次 涌水量 (Q)/m3·d−1 降深(S )/m 含水层厚度(M)/m 渗透系数(K)/m·d−1 ZK710 Ⅰ 1 220.49 13.7 118.58 0.144 2 136.34 8.50 118.58 0.132 Ⅱ 1 357.26 21.44 68.13 0.297 2 200.45 11.97 68.13 0.275 ZK909 Ⅰ 1 385.26 5.00 110.29 0.688 2 271.98 3.53 110.29 0.642 Ⅱ 1 485.40 7.80 60.22 1.190 2 220.49 3.55 60.22 1.049 表 3 多孔抽水试验观测孔参数表
Table 3. Parameters of observation holes for the porous pumping test
观测孔 距主孔距离(r)/m 降深值(S)/m 导水系数值(T)/m2·d−1 含水层厚度(M)/m 渗透系数(K)/m·d−1 观1(ZK907) 145 16.44 10.61 282.96 0.037 观2(ZK900) 174 9.97 17.80 345.30 0.051 观3(ZK902) 542 4.53 18.17 281.57 0.064 观4(ZK510) 450 5.62 14.67 300.33 0.049 观5(ZK709) 131 6.80 17.72 285.18 0.062 观6(ZK1304) 406 4.70 17.91 296.61 0.060 表 4 压性断层附近抽水试验参数表
Table 4. Parameters of the pumping test near the piezotropic fault
孔号 抽水段 降次 涌水量 (Q)/m3·d−1 降深(S)/m 含水层厚度(M)/m 渗透系数(K)/m·d−1 ZK710 全段 1 330.05 10.00 186.13 0.186 2 213.67 6.47 186.13 0.171 SGZK1 全段 1 392.17 10.00 234.80 0.173 2 249.09 6.35 234.80 0.154 表 5 张性断层附近抽水试验参数表
Table 5. Parameters of the pumping test near the tensional fault
孔号 全段 降次 涌水量 (Q)/m3·d−1 降深(S)/m 含水层厚度(M)/m 渗透系数(K)/m·d−1 ZK909 全段 1 495.54 3.00 170.51 0.955 2 256.61 1.55 170.51 0.841 -
[1] 王明章, 张林, 王伟, 陈萍, 陈登齐, 洪运胜. 贵州省岩溶区地下水与地质环境[M]. 北京: 地质出版社, 2015.WANG Mingzhang, ZHANG Lin, WANG Wei, CHEN Ping, CHEN Dengqi, HONG Yunsheng. Groundwater and geological environment in karst area of Guizhou Province[M]. Beijing: Geological Publishing House, 2015. [2] 宁黎元, 熊舒宁. 数值模拟查明地下水系统隐伏边界位置及其性质方法探讨[J]. 贵州地质, 2012, 29(1):48-51. doi: 10.3969/j.issn.1000-5943.2012.01.011NING Liyuan, XIONG Shuning. Study on the hidden boundary location and its property of groundwater system by numerical simulation[J]. Guizhou Geology, 2012, 29(1):48-51. doi: 10.3969/j.issn.1000-5943.2012.01.011 [3] 寇西昌. 贵州瓮福磷矿小坝矿段群孔抽水及其实用意义[J]. 贵州地质, 1987(2):211-223.KOU Xichang. Many cores unwatering and its practice significance, Xiaoba mine gallery, Wengfu phosphate mine, Guizhou[J]. Guizhou Geology, 1987(2):211-223. [4] 贵州省地质调查院. 贵州志/中国区域地质志[M]. 北京: 地质出版社, 2017.Guizhou Provincial Institute of Geological Survey. The Regional Geology of China, Guizhou Province[M]. Beijing: Geological Publishing House, 2017. [5] 蒲开兴, 蒲庆隆, 曾凡祥, 蔡健龙, 任永林. 贵州福泉市英坪磷矿水文地质条件与深部工程突水灾害防治[J]. 中国地质调查, 2021, 8(5):101-107.PU Kaixing, PU Qinglong, ZENG Fanxiang, CAI Jianlong, REN Yonglin. Study on the hydrogeological conditions and prevention of water invasion hazard in deep engineering of Yingping phosphate mine in Fuquan City of Guizhou Province[J]. Geological Survey of China, 2021, 8(5):101-107. [6] 陈萍, 王明章. 基于地下水开发的岩溶地下水系统类型划分方案探讨[J]. 中国岩溶, 2015, 34(3):234-237.CHEN Ping, WANG Mingzhang. A classification scheme of karst groundwater systems based on groundwater exploitation[J]. Carsologica Sinica, 2015, 34(3):234-237. [7] 郭崇光, 李振栓, 赵莹, 杨展. 水文地球物理测井方法与应用[M]. 北京: 煤炭工业出版社, 2006. [8] 韩凯, 梁永平, 严良俊, 梁东辉, 申豪勇, 唐春雷. 综合物探调查晋祠断裂对晋祠泉流域岩溶水控制作用效果分析[J]. 中国岩溶, 2020, 39(5):745-752.HAN Kai, LIANG Yongping, YAN Liangjun, LIANG Donghui, SHEN Haoyong, TANG Chunlei. Control of the Jinci fault on karst water in the Jinci spring basin revealed by integrated geophysical surveys[J]. Carsologica Sinica, 2020, 39(5):745-752. [9] 王明章, 幸绍汉, 王清友, 陈忠详, 朱春孝, 黄根荣. 贵州省遵义市西北郊高坪水源地供水水文地质初勘报告[R]. 遵义: 贵州省地质矿产局第二水文地质工程地质大队, 1991. [10] 王明章. 贵州寒武系白云岩山间盆地型水源地混合模拟问题探讨: 以海龙坝水源地为例[J]. 中国岩溶, 1993, 12(1):36-47.WANG Mingzhang. Approach on hybrid simulation for groundwater field of Cambrian dolostone intermontane basin in Guizhou: A case of Hailongba[J]. Carsologica Sinica, 1993, 12(1):36-47. [11] 李富, 邓国仕, 袁建飞, 王德伟, 唐业旗, 周一敏. 断层破碎带综合地球物理找水模式: 以甘田坝村探采结合井为例[J]. 中国岩溶, 2019, 38(3):344-352.LI Fu, DENG Guoshi, YUAN Jianfei, WANG Dewei, TANG Yeqi, ZHOU Yimin. Comprehensive geophysical model for water prospecting in fault fracture zone: A case study of water supply well siting at Gantianba village[J]. Carsologica Sinica, 2019, 38(3):344-352. [12] 程亚平, 蒋灵芝, 黎柳月, 李善民, 冯志秦. 综合物探技术探测平果铝厂赤泥堆场岩溶发育特征[J]. 中国岩溶, 2016, 35(6):688-698.CHENG Yaping, JIANG Lingzhi, LI Liuyue, LI Shanmin, FENG Zhiqin. Integrated geophysical prospecting technology to detect the characteristics of karst development in red mud dump of Pingguo aluminum plant[J]. Carsologica Sinica, 2016, 35(6):688-698. [13] 杨兴玉, 孟庆田, 向刚, 陆跃荣, 宋普洪, 刘波, 何永川, 王嘉铭. 贵州省福泉市大湾磷矿勘探报告[R]. 都匀: 贵州省地质矿产勘查开发局一〇四地质大队, 2021.YANG Xingyu, MENG Qingtian, XIANG Gang, LU Yuerong, SONG Puhong, LIU Bo, HE Yongchuan, WANG Jiaming. Exploration Report of Dawan phosphate mine, Fuquan City, Guizhou Province[R]. Duyun: 104 Geological Brigade of Guizhou Geological and Mineral Exploration and Development Bureau, 2021. [14] 孙其昌. 在大泉边进行多孔多阶段非稳定流抽水试验水文地质参数的计算及水位预报[J]. 中国岩溶, 1987, 6(4):55-61.SUN Qichang. Calculation of hydrogeological parameters: Multiple-stage multiple-well unsteady flow pumping test beside a large karst spring[J]. Carsologica Sinica, 1987, 6(4):55-61. [15] 金光炎. 地下水文学初步与地下水资源评价[M]. 南京: 东南大学出版社, 2009. [16] 吕全标, 胡晓农, 曹建华, 黄芬, 朱昊. 基于钻孔抽水试验和示踪试验的岩溶地区含水层结构研究[J]. 中国岩溶, 2017, 36(5):727-735.LV Quanbiao, HU Xiaonong, CAO Jianhua, HUANG Fen, ZHU Hao. Aquifer structure of karst areas derived from borehole pumping and tracer tests[J]. Carsologica Sinica, 2017, 36(5):727-735. [17] 冯来泉. 物探测井在地热开发中的应用[J]. 地球学报, 2000, 21(2):212-215. doi: 10.3321/j.issn:1006-3021.2000.02.020FENG Laiquan. The application of geophysical logging to geothermal development[J]. Journal of the Earth, 2000, 21(2):212-215. doi: 10.3321/j.issn:1006-3021.2000.02.020 [18] 王明章, 陈萍, 王中美, 王诗扬. 贵州省岩溶地下水系统及地下水赋存规律研究[M]. 北京: 地质出版社, 2018.WANG Mingzhang, CHEN Ping, WANG Zhongmei, WANG Shiyang. Research on karst groundwater system and groundwater occurrence conditions in Guizhou Province[M]. Beijing: Geological Publishing House, 2018. [19] 向刚, 曾牡丹, 王嘉铭, 陈体云, 何永川, 张华湘, 杨子林. 钻孔简易水文地质编录与测井结合对岩溶含水层含水性划分探讨:以福泉市大湾磷矿为例[J]. 贵州地质, 2021, 38(2):208-212. doi: 10.3969/j.issn.1000-5943.2021.02.013XIANG Gang, ZENG Mudan, WANG Jiaming, CHEN Tiyun, HE Yongchuan, ZHANG Huaxiang, YANG Zilin. Division of water-bearing property with combination of simple hydrogeological logging and borehole logging: Take Dawan phosphate mine of Fuquan for example[J]. Guizhou Geology, 2021, 38(2):208-212. doi: 10.3969/j.issn.1000-5943.2021.02.013