阿尔金北缘塔东南坳陷一带深部卤水钾盐矿地质特征与成矿规律浅析

A Preliminary Analysis and Aspects of the Geological Characteristics and Ore-forming Regularities of Deep Brine Potash Deposits in southeast Tarim depression of the Northern Margin of the Altyn Orogeny

阿尔金北缘分布一系列钾盐矿床,是我国重要的钾盐矿生产基地。以阿尔金北缘、塔里木东南坳陷区南部边缘钾盐矿床为研究对象,开展地质、物探及钻探等方面研究。研究表明,该钾盐矿床成因类型为陆成盐湖矿床,以钾为主伴生有钠、镁盐、溴,形成液体矿和固体矿,液体矿由潜卤水和承压卤水矿体组成,固体矿由盐壳石盐矿组成。深部卤水钾盐矿床物质主要来自南部阿尔金山区和塔里木盆地古盐再溶解补给。阿尔金山前若羌坳陷中丰富的盐类组份来源、半封闭构造环境和多风干旱气候条件是形成卤水钾盐矿床的主要条件。阿尔金北缘一带盆地沉降中心可能存在深藏含钾卤水矿床,该区域具良好的找矿前景。

The northern margin of the Altyn Orogeny in the foreland region hosts a series of potash deposits,constituting a significant production base for potash salts in China.This paper focuses on the potash deposits on the southern margin of the southeast Tarim Basin,systematically conducting geophysical,geochemical,and drilling investigations.The research indicates that the genesis of these potash deposits belongs to the continental salt lake type,primarily composed of potassium with associated sodium,magnesium salts,and bromine.Both liquid and solid ores are present,with the liquid ore consisting of subsurface brines and pressurized brine bodies,while the solid ore is composed of halite and sylvite.The deep brine potash deposits in this area primarily originate from the ancient salt dissolution and replenishment from the southern Altyn Mountains and the Tarim Basin.The abundant salt components in the rich source region,the semiclosed tectonic environment,and the windy arid climate in the Front RuoQiang Basin of the Altyn Orogeny are identified as the main conditions for the formation of these deposits.The basin's sedimentary center in the Front Altyn region may conceal deeply buried potassium-containing brine deposits,suggesting promising prospects for exploration in this region.