鄂尔多斯盆地神木—米脂地区本溪组含铝岩系中锂的富集机理研究  

Mechanism of Lithium Enrichment in Bauxite Deposits of the Benxi Formation in Shenmu-Mizhi Area,Ordos Basin

作　　者：潘博[1,2] 赵伟波 周星泽[3] 王怀厂 张辉[1,2] 史云鹤[1,2] 陈宇航[1,2] 姚亦芸[4] 郭睿良 余瑜[6] PAN Bo;ZHAO WeiBo;ZHOU XingZe;WANG HuaiChang;ZHANG Hui;SHI YunHe;CHEN YuHang;YAO YiYun;GUO RuiLiang;YU Yu(Research Institute of Exploration and Development,PetroChina Changqing Oilfield Company,Xi’an 710018,China;National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Fields,Xi’an 710018,China;New Energy Business Department,PetroChina Changqing Oilfield Company,Xi’an 710018,China;Logging Technology Research Institute,China National Logging Corporation,Xi’an 710077,China;School of Earth Sciences and Engineering,Xi’an Shiyou University,Xi’an 710065,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]中国石油长庆油田分公司勘探开发研究院,西安710018 [2]低渗透油气田勘探开发国家工程实验室,西安710018 [3]中国石油长庆油田分公司新能源事业部,西安710018 [4]中国石油集团测井有限公司测井技术研究院,西安710077 [5]西安石油大学地球科学与工程学院,西安710065 [6]油气藏地质及开发工程国家重点实验室(成都理工大学),成都610059

出　　处：《沉积学报》2025年第2期481-499,共19页Acta Sedimentologica Sinica

基　　金：中国石油长庆油田分公司勘探事业部技术研发项目(2022-40)。

摘　　要：【目的】锂(Li)是我国重要战略性金属和新能源金属之一。鄂尔多斯盆地含铝岩系分布广,近年来,鄂尔多斯盆地陇东地区铝土岩天然气勘探获重大突破,勘探中发现含铝岩系中伴生大量的锂资源。探明含铝岩系中Li的赋存形势和富集规律,不仅对古气候古环境研究具有重要的意义,也可以为Li资源的勘探开发提供有力支撑。【方法】以鄂尔多斯盆地中东部本溪组含铝岩系为研究对象,在前人认识和研究进展的基础上,通过岩心观察、钻井资料、地球化学试验等方法揭示了含铝岩系中Li的基本特征、赋存方式和富集规律。【结果】Li在含铝岩系中的分布相对不均匀,一般在含铝岩系中上部富集,在岩性序列中,Li主要富集在铝土质黏土岩和铝土岩中,在铝土质铁矿中含量较低。Li与Al_(2)O_(3)、SiO_(2)及Al_(2)O_(3)/SiO_(2)比值关系均先为正相关性,后呈负相关。【结论】炎热潮湿多雨的古气候及碱性环境有利于黏土矿物的形成,促进Li^(+)与Al^(3+)、Mg^(2+)发生类质同象作用赋存在黏土矿物中,随着脱硅富铝作用增强,由于缺少足够的黏土矿物,Li在铝土岩中的含量急剧降低。[Objective]Lithium constitutes a critical strategic and new energy metal within China.The Ordos Basin features a widespread distribution of bauxite deposits.Recent years have seen a major breakthrough in bauxite gas exploration within the Longdong area of the Ordos Basin.Exploration has uncovered considerable reserves of Li resources associated with the bauxite deposits.Consideration of the occurrence and enrichment patterns of Li in bauxite deposits has significant academic value for studying paleoclimate and paleoenvironments,and also offers robust support for the exploration and development of Li resources.[Methods]Focusing on the Al-bearing rock series of the Benxi Formation in the central and eastern Ordos Basin,this study builds upon classical understandings and recent research advancements to investigate the fundamental characteristics,modes of occurrence and enrichment patterns of Li,employing core observation,drilling data and geochemical testing.[Results]The findings reveal that Li is unevenly distributed in the bauxite deposits,with a substantial range of variation.Generally,Li is most highly concentrated in the middle and upper segments of the deposits.It is predominantly concentrated in bauxite clay rock and bauxite rock,but is comparatively rare in bauxite iron ore.Initially,Li is positively correlated with Al_(2)O_(3),SiO_(2) and the Al_(2)O_(3)/SiO_(2) ratio,which subsequently transitions to a negative correlation.[Conclusions]The hot,humid and high rainfall conditions of the paleoclimate together with an alkaline environment facilitated the formation of clay minerals and enhanced the isomorphic substitution of Li^(+)for Al^(3+)and Mg^(2+),but as desilication and aluminum enrichment intensify the Li content of bauxite rock sharply decreases,attributable to the lack of clay minerals.

关 键 词：鄂尔多斯盆地 含铝岩系 锂 赋存方式 富集规律 

分 类 号：P618.71[天文地球—矿床学]