辽宁宽甸地区硼矿区域成矿特征及找矿标志

辽宁宽甸地区硼矿资源丰富,其矿床赋存于早元古代下辽河群里尔屿岩组一段金云母蛇纹岩、蛇纹石化大理岩中,具成矿专属性,并与辽吉花岗岩空间关系密切。同时后期褶皱构造及断裂构造叠加作用使矿床受到破坏及改造。1∶20万化探测量结果显示,宽甸地区硼元素背景值为3.9ppm,取异常下限6.0ppm,不同异常的峰值在14.5~450ppm之间;物探磁法测量显示,区内硼矿床(点)主要分布在较规整的条带状正磁异常的内部及其边部梯级带内。本文据此提出:结合"就矿找矿"经验,在确定成矿有利层位的基础上,物化探异常可作为区内硼矿床重要的找矿标志。

The Regional Metallogenic Characteristics and Prospecting Criteria of Boron Deposit in Kuandian Area of Liaoning Province

Boron deposit in Kuandian area of Liaoning province has rich resources. The boron deposits occur in Liaohe group Lieryu formation, which lithology is mainly composed of phlogopite serpentinite and serpentine marble showing the obvious metallogenetic specialization. And boron deposits have a close space relationship with Liaoji granite. Not only that, the destruction and reconstruction of late fold and fault structure cannot be ignored. The background and threshold of boron are 3.9ppm and 6.0ppm basing on some geochemical prospecting data in scale 1:200000. The peak values are between 14.5ppm and 450ppm of different anomalies. In addition, Kuandian boron deposits are distributed in some strapped positive magnetic anomalies or occurring within the gradient grade zone of some magnetic anomalies. Accordingly, basing on the position of the favourite ore-forming country rocks and connecting all obtained information with the boron prospecting model, geochemical and geophysical anomaly should be regarded as important criteria for ore prospecting.