干旱区生态环境知识资源中心(Arid): Volcanic and Saline Lithium Inputs to the Salar de Atacama

Arid

DOI	10.3390/min10020201
	Volcanic and Saline Lithium Inputs to the Salar de Atacama
	Godfrey, Linda 1; Alvarez-Amado, Fernanda 2,3
通讯作者	Godfrey, Linda
来源期刊	MINERALS
EISSN	2075-163X
出版年	2020
卷号	10 期号:2
英文摘要	The Li-rich brine contained within the halite body of the Salar de Atacama is uncommon for two reasons: First, it has an exceptionally high Li concentration, even compared to other closed basins in the Li triangle of South America; and second, it is widespread within the halite nucleus and not restricted to a localized area. This study focusses on the southern half of the salar where Li production occurs and draws comparisons with its northern neighboring basin through which the Loa river flows. Concentration and isotope data for water inflowing to this part of the salar were obtained from surface inflow as well as wells located within the alluvial fans on its eastern margin. Lithium varies between 0.2 and 20 mg/L before reaching the salar where small amounts of the brine and or salts that precipitated from it can increase its concentration up to 400 mg/L or higher. The delta Li-7 of the inflow water varies between +4.9 parts per thousand and +11.2 parts per thousand and increases to +12.6 parts per thousand within the salar margin, consistent with salar brine based on reported measurements. Boron isotopes indicate that it is unlikely that solutes are derived from sedimentary evaporites or mineral cements, unlike the situation in the adjacent Loa basin. Water that flows through an aquifer laterally confined by a basement block and a line of volcanoes has a notably higher delta Li-7 than other inflow water, around +9 parts per thousand, and increasing to +10.5 parts per thousand. delta Li-7 values are overall higher than were measured in the adjacent Loa basin, indicating that here the water-rock reactions for Li are more evolved due to longer residence times. Lithium concentrations increased with sodium and chloride, but sedimentary evaporites are shown to be unimportant from delta B-11. This is accounted for two ways: evaporated saline inflow leaks from higher elevation basins and inflows are partly derived from or modified by active volcanic systems. Active and dormant volcanoes plus the massive Altiplano-Puna magmatic body are important as heat sources, which enhance water-rock reactions. The large topographic difference between the mean elevation of Altiplano on which these volcanoes sit and the salar surface allows hydrothermal fluids, which would otherwise stay deep below the surface under the modern arc, to uplift at the salar.
英文关键词	lithium isotopes boron isotopes volcanism water-rock interaction
类型	Article
语种	英语
国家	USA ; Chile
开放获取类型	gold
收录类别	SCI-E
WOS记录号	WOS:000522452900116
WOS关键词	BORON ISOTOPE FRACTIONATION ; NORTHERN CHILE ; GROUNDWATER-FLOW ; CLOSED-BASIN ; BRINE ; EVOLUTION ; ORIGIN ; DESERT ; STRATIGRAPHY ; ALTIPLANO
WOS类目	Geochemistry & Geophysics ; Mineralogy ; Mining & Mineral Processing
WOS研究方向	Geochemistry & Geophysics ; Mineralogy ; Mining & Mineral Processing
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/315182
作者单位	1.Rutgers State Univ, Dept Earth & Planetary Sci, Piscataway, NJ 08504 USA; 2.Univ Concepcion, Dept Ciencias Tierra, Casilla 160-C, Concepcion 78349, Chile; 3.Univ Chile, Millennium Nucleus Met Tracing Subduct, FCFM, Santiago 7580150, Chile
推荐引用方式 GB/T 7714	Godfrey, Linda,Alvarez-Amado, Fernanda. Volcanic and Saline Lithium Inputs to the Salar de Atacama[J],2020,10(2).
APA	Godfrey, Linda,&Alvarez-Amado, Fernanda.(2020).Volcanic and Saline Lithium Inputs to the Salar de Atacama.MINERALS,10(2).
MLA	Godfrey, Linda,et al."Volcanic and Saline Lithium Inputs to the Salar de Atacama".MINERALS 10.2(2020).