首页|Contrasting sources and enrichment mechanisms in lithium-rich salt lakes:A Li-H-0 isotopic and geochemical study from northern Tibetan Plateau

Contrasting sources and enrichment mechanisms in lithium-rich salt lakes:A Li-H-0 isotopic and geochemical study from northern Tibetan Plateau

扫码查看
Lithium(Li),a crucial mineral resource for modern high-tech industries,is notably abundant in the north-ern Tibetan Plateau,primarily within lithium-rich salt lakes.However,the exploration and development of these resources are hindered due to an incomplete understanding of their nature and origin.Here we present results from a comprehensive study on the hydrochemical parameters,whole-rock geochemistry,H-O isotopes,and Li concentrations in surface brine,river water,geothermal springs,and associated rocks from two representative lithium-enriched salt lakes,the Laguo Co(LGC)and Cangmu Co(CMC)in Tibet to understand the genetic mechanisms.Our water-salt balance calculations and H-O isotopic analysis reveal that Li in LGC and CMC primarily originates from the Suomei Zangbo(SMZB,~91%)and Donglong Zangbo(DLZB,~75%)rivers,respectively.It is estimated that the LGC and CMC took a minimum of 6.0 ka and 3.0 ka to accumulate their current lithium resources,respectively.The distinct geological characteristics reflect evolutionary differences between the two lakes,suggesting diverse lithium sources and enrich-ment processes.The high lithium ion concentration and light lithium isotope composition in the SMZB river waters indicate the genetic relationship with lithium-enriched geothermal springs in the Tibetan Plateau.Our results suggest that lithium in the LGC originates from lithium-enriched geothermal springs and is primarily supplied through the small-scale SMZB river.In contrast,the formation and evolution of CMC are influenced by the northern Lunggar rifts,receiving a prolonged and stable input from the DLZB,resulting in high lithium concentrations and isotopic values.The absence of lithium-enriched geothermal springs and the prevalence of silicate rocks in the CMC catchment suggest that lithium may be sourced from the weathering of silicate rocks,such as granitic pegmatite veins containing lithium-rich beryl,widely distributed in the upstream area of DLZB.The forward modeling approach,quantifying the con-tribution fractions of different reservoirs(atmospheric precipitation,silicate,carbonate,and evaporite),indicates that the distinct lithium concentrations in the mainstream(>1 mg/L)and tributaries(<0.1 mg/L)are positively correlated with the ratio of silicate contributions to carbonate contributions,suggesting that dissolved lithium in river waters primarily originates from the weathering and dissolu-tion of silicate rocks.The distinct sources and enrichment mechanisms of lithium in these two salt lakes are attributed to various evolutionary processes,topographical features,hydrological factors,fundamen-tal geological settings,and tectonic histories,despite their spatial proximity.Furthermore,our study highlights the significant role of rivers in the formation of young salt lakes,in addition to geothermal springs.

Lithium isotopesHydrochemistrySalt lakesEnrichment mechanismTibetan Plateau

Fei Xue、Hongbing Tan、Xiying Zhang、M.Santosh、Peixin Cong、Lu Ge、Chao Li、Guohui Chen、Yu Zhang

展开 >

School of Earth Sciences and Engineering,Hohai University,Nanjing 210098,PR China

Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources,Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes,Qinghai Institute of Salt Lakes,Chinese Academy of Sciences,Qinghai 810008,PR China

School of Earth Sciences and Resources,China University of Geosciences Beijing,Beijing 100083,PR China

Department of Earth Sciences,University of Adelaide,SA 5005,Australia

Yonsei Frontier Lab,Yonsei University,Seoul 0372,Korea

展开 >

Second Tibetan Plateau Scientific Expedition and Research Program(STEP)国家自然科学基金中央高校基本科研业务费专项

2022QZKK0202U22A20573B230201014

2024

地学前缘(英文版)
中国地质大学(北京) 北京大学

地学前缘(英文版)

CSTPCD
影响因子:0.576
ISSN:1674-9871
年,卷(期):2024.15(2)
  • 101