摘要
四川盆地普光地区的川宣地1井和川宣2井在三叠系嘉陵江组四段+五段和雷口坡组一段钻遇高浓度钾锂卤水和可溶厚层石盐型杂卤石钾盐矿,实现了四川盆地海相深部锂钾勘探重大突破。通过践行“气钾锂兼探”的勘探理念,基于大量油气钻井、测井、地震和地球化学资料,对富钾锂卤水和石盐型杂卤石的地质特征、富集条件和成矿演化模式开展研究。研究表明:①四川盆地东北部嘉陵江组四段+五段—雷口坡组一段发育膏云坪、盐湖和蒸发坪沉积体系,发育相对较好的卤水储集体,是固液两相钾锂资源沉积的有利层段,形成了普光、通南巴和元坝3个规模成盐聚钾中心;②石盐型杂卤石厚度大、分布广,且具有可溶性特征,储层卤水钾锂离子含量高,钾锂资源形成固液叠置的“三层楼”结构(下层为嘉陵江组四段+五段下部薄层卤水储层,中层为石盐型杂卤石钾盐矿层,上层为雷口坡组一段富钾锂卤水储层);③钾锂资源具有三元富集成矿规律特征,即杂卤石和绿豆岩纵向叠置是钾锂资源“双源补给、近源释放”的成矿物质基础,原生海水和石膏脱水是深部卤水的主要来源,而多期次构造作用是石盐型杂卤石和锂钾卤水富集的关键;④成矿过程经历了成盐聚钾锂期、水岩反应初期、改造聚集期和富集定型期4个阶段,嘉陵江组四段+五段石盐型杂卤石层为钾盐溶采的主要目标,雷口坡组一段卤水层则是钾锂综合勘探开发的重点。
Wells CXD1 and CX2 revealed high-concentration potassium-and lithium-containing brines and thick layers of halite-type polyhalite potash deposit in the 4th and 5th members of Triassic Jialingjiang Formation and 1st Member of Leikoupo Formation(Jia 4 Member,Jia 5 Member and Lei 1 Member)in Puguang area,Sichuan Basin,achieving breakthroughs in the exploration of deep marine potassium and lithium resources in the Sichuan Basin.Following the concept of“gas-potassium-lithium integrated exploration”and using the drilling,logging,seismic and geochemical data,we studied the geological and enrichment conditions,metallogenic model of potassium-rich and lithium-rich brines and halite-type polyhalite.First,the sedimentary systems of gypsum-dolomite flats,salt lake and evaporated flat are developed in Jia 4 Member,Jia 5 Member,and the 1st member of Leikoupo Formation(Lei 1 Member)in northeastern Sichuan Basin,forming three large-scale salt-gathering and potassium formation centers in Puguang,Tongnanba and Yuanba,and developing reservoirs with potassium-rich and lithium-rich brines,which are favorable for the deposition of potassium and lithium resources in both solid or liquid phases.Second,the soluble halite-type polyhalite has a large thickness and wide distribution,and the reservoir brine has a high content of K^(+)and Li^(+).A solid-liquid superimposed“three-story structure”(with the lower thin-layer of brine reservoir in lower part of Jia 4 Member+Jia 5 Member,middle layer of halite-type polyhalite potash deposit,upper layer of potassium-rich and lithium-rich brine reservoir in Lei 1 Member)is formed.Third,the ternary enrichment and mineralization patterns for potassium and lithium resources were determined.Vertical superposition of polyhalite and green bean rocks is the mineral material basis of potassium-lithium resources featuring“dual-source replenishment and proximal-source release”,with primary seawater and gypsum dehydration as the main sources of deep brines,while multi-stage tectonic modification is the key to the enrichment of halite-type polyhalite and potassium-lithium brines.Fourth,the ore-forming process has gone through four stages:salt-gathering and potassium-lithium accumulation period,initial water-rock reaction period,transformation and aggregation period,and enrichment and finalization period.During this process,the halite-type polyhalite layer in Jia 4 Member and Jia 5 Member is the main target for potassium solution mining,while the brine layer in Lei 1 Member is the focus of comprehensive potassium-lithium exploration and development.
作者
苏克露
仲佳爱
王威
石文斌
陈祖庆
李宇平
范志伟
王建波
刘勇
潘蓓
刘治成
蒋艳霞
梁子锐
张煜颖
王富明
SU Kelu;ZHONG Jiaai;WANG Wei;SHI Wenbin;CHEN Zuqing;LI Yuping;FAN Zhiwei;WANG Jianbo;LIU Yong;PAN Bei;LIU Zhicheng;JIANG Yanxia;LIANG Zirui;ZHANG Yuying;WANG Fuming(Sinopec Exploration Company,Chengdu 610041,China;The 2nd Geological Brigade of Sichuan,Chengdu 610081,China;Sichuan Institute of Land Science and Technology,Chengdu 610045,China)
出处
《石油勘探与开发》
北大核心
2025年第1期241-252,共12页
Petroleum Exploration and Development
基金
国家重点研发计划课题“深部钾盐探测方法与技术研究”(2017YFC0602804)
四川省地质局项目“基于遥感和放射性能谱的四川盆地钾盐找矿方法”(SCDZ-KJXM202403)。
关键词
锂钾资源
石盐型杂卤石
富钾锂卤水
富集机理
三叠系
嘉陵江组
雷口坡组
普光地区
四川盆地
potassium-lithium resources
halite-type polyhalite
potassium-rich and lithium-rich brine
enrichment mechanism
Triassic
Jialingjiang Formation
Leikoupo Formation
Puguang area
Sichuan Basin
