Geology and minerogenetic condition of the Lenghu sandstone-type uranium deposit in the northern margin of Qaidam Basin
-
摘要:
冷湖地区砂岩型铀矿是近年柴北缘新发现的具有工业价值的铀矿床,为了进一步研究该地区砂岩型铀成矿岩石学及矿物学特征、铀成矿条件等问题,本文在野外地质调查的基础上,利用偏光显微镜结合电子探针分析手段,对该区内大煤沟组中含矿岩石进行了系统研究。结果表明:研究区中侏罗统大煤沟组含矿岩石类型主要为(粉)砂质泥岩、薄层煤及细粒石英杂砂岩,整体发育一系列后生蚀变。研究区北东侧安南坝山古元古界达肯达坂群及赛什腾山海西期花岗岩为区内砂岩型铀成矿提供了丰富的铀源。砂岩型铀矿中铀主要以独立铀矿物沥青铀矿的形式赋存,其次含有少量分散吸附态铀,沥青铀矿总体呈不规则粒状、星点状、“串珠状、线状”及粉末状赋存于黄铁矿边缘、裂隙部位或黄铁矿与方解石的接触部位,吸附态铀主要赋存于炭屑及煤线内;区内沥青铀矿为柴北缘地区首次揭露并发现的独立铀矿物,总体上填补了柴北缘地区无独立铀矿物出露的空白。铀成矿条件方面,含矿目的层中方解石的发育,显示了铀成矿流体富含CO2、H2O等挥发分和矿化剂,其次出露的众多还原性介质(油气、炭屑及黄铁矿等)为区内砂岩型铀成矿提供了氧化还原反应必需的还原剂,最终将U6+还原成U4+以沥青铀矿等形式沉淀成矿。
Abstract:The Lenghu sandstone-type uranium deposit is the newly discovered industrial deposit in the northern margin of Qaidam basin. Based on the field geological survey, the ore-bearing rocks in the Dameigou Formation in this area were studied by means of polarizing microscope and electron probe analysis to further clarify the characteristics of uranium source, petrology and mineralogy of Lenghu sandstone-hosted uranium deposit. Results show that the ore-bearing rocks in the Dameigou Formation are mainly (silty) sandy mudstone and thin layer coal and fine-grained quartz greywacke, accompanied with a series of epigenetic alteration phenomena. The Lower Proterozoic Dakendaban Group and Hercynian granite in the northeastern part of the study area provide abundant uranium sources for uranium mineralization. The uranium minerals in this deposit are mainly pitchblende and minor adsorption state of uranium. In general, the pitchblende occurs in irregular granular, stellate, "beadlike, linear" and powdery forms at the edge of pyrite, in the crack or on the contact between pyrite and calcite. The adsorbed uranium mainly occurs in the carbon chips and coal lines. The pitchblende deposit is the first exposed and discovered independent uranium mineral in the northern margin of Qaidam basin, which generally fills the blank of no independent uranium mineral exposed in this area. The presence of calcite in ore-bearing layer indicates that the uranium mineralization fluid is rich in CO2, H2O etc. volatile and mineralizer. In addition, many exposed reducing medium (oil and gas, carbon and pyrite, etc.) provides reductant required for REDOX reaction of this type of deposit, which eventually reduces U6+ to U4+ and results in precipitation of pitchblende.
-
-
图 1 柴北缘冷湖地区地质简图(底图据周雪峰等,2018修改)
Figure 1.
表 1 冷湖铀矿床样品特征及采样位置
Table 1. Sample characteristics and sampling location in the Lenghu uranium deposit
表 2 柴北缘冷湖砂岩型铀矿床铀矿物电子探针分析结果(%)
Table 2. Results of electron probe analysis of uranium minerals in the northern margin of Qaidam basin (%)
-
Bai Yadong, Yang Wei, Ma Feng, Shi Zhenghao, Wang Zhaobing. 2019. Tectonic feature and oil and gas exploration direction of Lenghu 7-Nanbaxian Area on North Margin of Qaidam Basin[J]. Special Oil and Gas Reservoirs, 26(1): 75-79(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTotal-TZCZ201901013.htm
Cheng Y H, Wang S Y, Jin R S, Li J G, Ao C, Teng X M. 2019. Global Miocene tectonics and regional sandstone-style uranium mineralization[J]. Ore Geology Reviews, 106: 238-250. doi: 10.1016/j.oregeorev.2019.02.003
Feng Wei, Song Xiansheng. 2018. Study on the type and prospecting direction of sandstone-type uranium deposits in the northern margin of the Qaidam basin[J]. Western Resources, (5): 45-47(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTotal-DZKT201701007.htm
Hu R Z, Bi X W, Zhou M F. 2008. Uranium metallogenesis in South China and its relationship to crustal extension during the Cretaceous to Tertiary[J]. Economic Geology, 103(3): 583-598. doi: 10.2113/gsecongeo.103.3.583
Huang Guangwen, Pan Jiayong, Zhang Zhanfeng, Huang Guangnan, Liao Zhiquan, Du Houfa. 2017. Study on petrological characteristics and distribution of uranium minerals of sandstones in Mengqiguer uranium by electron microprobe, Xinjiang[J]. Rock and Mineral Analysis, 36(2): 209-220(in Chinese with English abstract).
Huang Guangwen, Yu Fucheng, Pan Jiayong, Cheng Zhengle, Wu Dehai, Xue Wanwen, Song Taizhong, Li Shanping. 2021. Genesis of pyrite from the Mengqiguer uranium deposit in Ili Basin of Xinjiang and its implication for mineralization[J]. Geology in China, 48(2): 507-519(in Chinese with English abstract).
Joël Brugger, Liu W, Etschmann B, Mei Y, Sherman D M, Testemale D. 2016. A review of the coordination chemistry of hydrothermal systems, or do coordination changes make ore deposits?[J]. Chemical Geology, 447: 219-253. doi: 10.1016/j.chemgeo.2016.10.021
Jin Ruoshi, Cheng Yinhang, Li Jianguo, Sima Xianzhang, Miao Peisen, Wang Shaoyi, Ao Cong, Li Hongliang, Li Yangfeng, Zhang Tianfu. 2017. Late Mesozoic continental basin "Red and Black beds" coupling formation constraints on the sandstone uranium mineralization in northern China[J]. Geology in China, 44(2): 205-223(in Chinese with English abstract). http://www.researchgate.net/publication/320189651_Late_mesozoic_continental_basin_Red_and_Black_beds_coupling_formation_constraints_on_the_sandstone_uranium_mineralization_in_northern_China
Li Jie, Zhong Junwei, Yu Yang, Huang Xiaolong. 2013. Insights on magmatism and mineralization from micas in the Xihuashan granite, Jiangxi Province, South China[J]. Geochimica, 42(5): 393-404(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-DQHX201305001.htm
Liu Lin, Feng Wei, Chen Qing. 2013. Uranium forming conditions and exploration prospect in the northeast margin of Qaidamu[J]. Journal of East China Institute of Technology (Natural Science), 36(3): 249-254(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-HDDZ201303001.htm
Liu G Q, Zhao K D, Jiang S Y, Chen W. 2018. In-situ sulfur isotope and trace element analysis of pyrite from the Xiwang uranium ore deposit in South China: Implication for ore genesis[J]. Journal of Geochemical Exploration, 7: 1-17. http://www.sciencedirect.com/science/article/pii/S0375674217304612
Liu Wenjin, Dang Hongliang, Huang Guangnan, Huang Xianhao, Liu Binqiang, Zhang Yongan, Wang Weichao, Qi Lajia. 2019. Metallogenic Conditions and Prospecting Target of Sand Type Uranium Deposits in the Tuanyushan Area of Northern Qaidam Basin[J]. Northwestern Geology, 52(4): 232-240(in Chinese with English abstract).
Lu Yaozu. 2007. Ore potentiality of in-situ leaching sandstone-type uranium deposits in the Lower and Upper Tertiary in Lenghu, Qaidam[J]. Journal of Sichuan Geology, 27(2): 104-106(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTotal-SCDB200702007.htm
Song Guangyong, Gong Qingshun, Pang Hao, Xia Zhiyuan, Li Senming, Wu Jin, Tian Mingzhi, Huang Xuebing. 2020. High-precision sequence stratigraphy and sandbody architecture of the Lower Xiaganchaigou Formation in the slope area of Western Qaidam Basin[J]. Geology in China, 47(1): 188-200(in Chinese with English abstract).
Tao Jihua, Lin Qiuling, Li Xinghao, Cao Jun, Wang Andong, Xu Zhitian. 2020. Mineral chemical characteristics of biotites from the Jintan granites in Jiangxi Province and the implication for uranium enrichment[J]. Bulletin of Mineralogy, Petrology and Geochemistry, 39(2): 267-282(in Chinese with English abstract).
Wu D H, Pan J Y, Xia F, Huang G W, Lai J. 2019. The mineral chemistry of chlorites and its relationship with uranium mineralization from Huangsha uranium mining area in the Middle Nanling Range, SE China[J]. Minerals, 9(3): 199. doi: 10.3390/min9030199
Wang Dan, Wu Bailin, Cun Xiaoni, Sun Li, Xu Zigao, Zhan Jie, Yuan Kang. 2015. Coexistence of multiple energy minerals in Qaidam Basin and its geological significance[J]. Journal of Earth Sciences and Environment, 37(3): 55-67(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTotal-XAGX201503008.htm
Wu Dehai, Xia Fei, Pan Jiayong, Liu Guoqi, Huang Guolong, Liu Wenquan, Wu Jianyong. 2019. Characteristics of hydrothermal alteration and material migration of Mianhuakeng uranium deposit in northern Guangdong Province[J]. Acta Petrologica Sinica, 35(9): 2745-2764(in Chinese with English abstract). doi: 10.18654/1000-0569/2019.09.08
Xin Cunlin. 2007. Analysis on ore-formation conditions and character of in-situ leachable sandstone type u-ranium deposit in Lenghu region of Caidam basin[J]. Journal of Northwest Normal University (Natural Science), 43 (2): 93-97(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-XBSF200702022.htm
Xu Wen, Bao Jianping, Zhu Jianfeng, Tie Huijuan. 2012. Correlation of crude oil from Lenghu area in northern Qaidam Basin[J]. Global Geology, 31(2): 357-364(in Chinese with English abstract). http://epub.cnki.net/grid2008/docdown/docdownload.aspx?filename=SJDZ201202016&dbcode=CJFD&year=2012&dflag=pdfdown
Yu Dagan, Wu Rengui, Chen Peirong. 2005. Uranium Geology[M]. Harbin: Harbin Engineering University Press, 1-450(in Chinese).
Zhang Jindai, Xu Gaozhong, Chen Anping, Wang Cheng. 2005. Preliminary discussion on uranium metallogenic models of China's in situ leachable sandstone type uranium deposits[J]. Uranium Geology, 21(3): 139-145(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-YKDZ200503002.htm
Zhang Long, Chen Zhenyu, Tian Zejin, Huang Guolong. 2016. The application of electron microprobe dating method on uranium minerals in Changjiang granite, Northern Guangdong[J]. Rock and Mineral Analysis, 35(1): 98-107(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-YKCS201601018.htm
Zhang Xiao. 2012. A Review on Genesis of Mengqiquer Uranium Deposit in the Southern Margin of Yili Basin, Xinjiang[D]. Beijing: Beijing Research Institute of Uranium Geology(in Chinese with English abstract).
Zhou Fei, Wang Bo, Li Zhexiang, Sui Guojie, Qi Wenzhen, Cui Shoukai, Ma Jinye, Cheng Dingshu. 2019. Geochemical characteristics and accumulation elements controlling the natural gas in Lenghu tectonic belts of Qaidam Basin[J]. Natural Gas Geoscience, 30(10): 1496-1507(in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTotal-TDKX201910014.htm
Zhou Xuefeng, Zhang Yongshu, Yan Detian, Tang Jianrong, Wu Zhixiong, Ma Zisen, Zhou Fei, Zhao Rui, He Jie, Yu Chao. 2018. Quantitative Evaluation of sealing capacity of tertiary mudstone caprock in Lenghu Area, Qaidam Basin[J]. Earth Science, 43(S2): 226-233(in Chinese with English abstract). http://www.researchgate.net/publication/335079273_Quantitative_Evaluation_of_Sealing_Capacity_of_Tertiary_Mudstone_Caprock_in_Lenghu_Area_Qaidam_Basin
白亚东, 杨巍, 马峰, 石正灏, 王兆兵. 2019. 柴北缘冷湖七号-南八仙地区构造特征及油气勘探方向[J]. 特种油气藏, 26(1): 75-79. https://www.cnki.com.cn/Article/CJFDTOTAL-TZCZ201901013.htm
冯伟, 宋宪生. 2018. 柴达木盆地北缘砂岩型铀矿类型及找矿方向研究[J]. 西部资源, (5): 45-47. doi: 10.3969/j.issn.1672-562X.2018.05.021
黄广文, 潘家永, 张占峰, 黄广楠, 张涛, 廖志权, 杜后发. 2017. 应用电子探针研究蒙其古尔铀矿床含矿砂岩岩石学特征及铀矿物分布规律[J]. 岩矿测试, 36(2): 209-220. https://www.cnki.com.cn/Article/CJFDTOTAL-YKCS201702014.htm
黄广文, 余福承, 潘家永, 陈正乐, 吴德海, 薛万文, 宋泰忠, 李善平. 2021. 伊犁盆地蒙其古尔铀矿床黄铁矿成因特征及其对铀成矿作用的指示[J]. 中国地质, 48(2): 507-519. http://geochina.cgs.gov.cn/geochina/ch/reader/view_abstract.aspx?file_no=20210211&flag=1
金若时, 程银行, 李建国, 司马献章, 苗培森, 王少轶, 奥琮, 里宏亮, 李艳锋, 张天福. 2017. 中国北方晚中生代陆相盆地红-黑岩系耦合产出对砂岩型铀矿成矿环境的制约[J]. 中国地质, 44(2): 205-223. http://geochina.cgs.gov.cn/geochina/ch/reader/view_abstract.aspx?file_no=20170201&flag=1
李洁, 钟军伟, 于洋, 黄小龙. 2013. 赣南西华山花岗岩的云母成分特征及其对岩浆演化与成矿过程的指示[J]. 地球化学, 42(5): 393-404. https://www.cnki.com.cn/Article/CJFDTOTAL-DQHX201305001.htm
刘林, 冯伟, 陈擎. 2013. 柴达木东北缘铀成矿地质条件及找矿远景研究[J]. 东华理工大学学报(自然科学版), 36(3): 249-254. doi: 10.3969/j.issn.1674-3504.2013.03.001
刘文进, 党洪量, 黄广楠, 黄献好, 刘炳强, 张永安, 王伟超, 祁拉加. 2019. 柴达木盆地北缘团鱼山地区砂岩型铀矿成矿条件与找矿方向[J]. 西北地质, 52(4): 232-240. doi: 10.3969/j.issn.1009-6248.2019.04.018
路耀祖. 2007. 柴达木盆地冷湖地区古近-新近系可地浸砂岩型铀矿成矿前景[J]. 四川地质学报, 27(2): 104-106. doi: 10.3969/j.issn.1006-0995.2007.02.007
宋光永, 宫清顺, 庞皓, 夏志远, 李森明, 伍劲, 田明智, 黄学兵. 2020. 柴达木盆地西部斜坡区下干柴沟组下段高精度层序地层及砂体构型分析[J]. 中国地质, 47(1): 188-200. http://geochina.cgs.gov.cn/geochina/ch/reader/view_abstract.aspx?file_no=20200115&flag=1
陶继华, 林秋伶, 李鑫浩, 曹俊, 王安东, 徐志添. 2020. 江西金滩花岗岩中黑云母矿物化学特征及其对铀富集的启示[J]. 矿物岩石地球化学通报, 39(2): 267-282. https://www.cnki.com.cn/Article/CJFDTOTAL-KYDH202002017.htm
王丹, 吴柏林, 寸小妮, 孙莉, 徐梓皋, 詹杰, 袁康. 2015. 柴达木盆地多种能源矿产同盆地共存及其地质意义[J]. 地球科学与环境学报, 37(3): 55-67. doi: 10.3969/j.issn.1672-6561.2015.03.008
吴德海, 夏菲, 潘家永, 刘国奇, 黄国龙, 刘文泉, 吴建勇. 2019. 粤北棉花坑铀矿床热液蚀变与物质迁移研究[J]. 岩石学报, 35(9): 2745-2764. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB201909008.htm
辛存林. 2007. 柴达木盆地冷湖地区可地浸砂岩型铀矿化特征及成矿条件分析[J]. 西北师范大学学报, 43(2): 93-97. https://www.cnki.com.cn/Article/CJFDTOTAL-XBSF200702022.htm
徐文, 包建平, 朱建峰, 铁辉娟. 2012. 柴达木盆地北缘冷湖地区原油对比[J]. 世界地质, 31(2): 357-364. doi: 10.3969/j.issn.1004-5589.2012.02.017
余达淦, 吴仁贵, 陈培荣. 2005. 铀资源地质学[M]. 哈尔滨: 哈尔滨工程大学出版社, 1-450.
张金带, 徐高中, 陈安平, 王成. 2005. 我国可地浸砂岩型铀矿成矿模式初步探讨[J]. 铀矿地质, 21(3): 139-145. https://www.cnki.com.cn/Article/CJFDTOTAL-YKDZ200503002.htm
张龙, 陈振宇, 田泽瑾, 黄国龙. 2016. 电子探针测年方法应用于粤北长江岩体的铀矿物年龄研究[J]. 岩矿测试, 35(1): 98-107. https://www.cnki.com.cn/Article/CJFDTOTAL-YKCS201601018.htm
张晓. 2012. 伊犁盆地南缘蒙其古尔铀矿床成因研究[D]. 北京: 核工业北京地质研究院.
周飞, 王波, 李哲翔, 隋国杰, 祁文珍, 崔守凯, 马进业, 成定树. 2019. 柴达木盆地冷湖构造带天然气地球化学特征及成藏主控因素[J]. 天然气地球科学, 30(10): 1496-1507. doi: 10.11764/j.issn.1672-1926.2019.10.013
周雪峰, 张永庶, 严德天, 汤建荣, 吴志雄, 马子森, 周飞, 赵睿, 何杰, 于超. 2018. 柴达木盆地冷湖地区第三系泥岩盖层封盖能力定量评价[J]. 地球科学, 43(增刊2): 226-233. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX2018S2018.htm
-