河南省卢氏县黄柏沟花岗伟晶岩型铀矿地质特征及找矿预测

Study on characteristics and prospecting prediction of Huangbaigou granite pegmatite uranium deposit in Lushi county,Henan province

黄柏沟铀矿是在豫西地区灰池子岩体外围新发现的伟晶岩型铀矿,经过前期勘查取得了较好的找矿成果。本文通过对黄柏沟伟晶岩铀矿矿石特征和晶质铀矿的化学组成分析研究,初步探讨了伟晶岩成因,总结了该区的铀矿找矿标志及找矿方向。研究认为:(1)黑云母伟晶岩是该区的含矿岩石,岩石发育文像和伟晶结构,具有矿物粒度粗大、富含黑云母、硅高、钾富、铝过饱和等特点;(2)晶质铀矿是主要的矿石矿物,主要以2种状态赋存于黑云母伟晶岩中——一是以细小微脉赋存于黑云母生长节理中或边界接触面上,二是结晶较好的自形程度较高的晶质铀矿颗粒;(3)晶质铀矿主要元素为U,其次为Th、Pb,稀有元素Y相对富集,且与U关系密切;(4)下一步的重点找矿方向为灰池子岩体外接触带0~200 m内具有含矿伟晶岩特征的黑云母伟晶岩。

Huangbaigou ore deposit is a granitic pegmatite uranium deposit newly discovered in the periphery of Huichizi pluton in West Henan province.The Previous prospecting is successful.This paper deals with characteristics of the uranium ore and chemical composition of the crystalline uranium mineral,genesis of the pegmatite and the prospecting marks and direction.The ore is hosted in biotite pegmatite developed with graphic pegmatitic texture and characterized by large grain size,high content of biotite,i.e.high Si and K and Al supersaturation.Crystalline uranium mineral is the main ore mineral occurring as micro-veinlets at joints or at contact surfaces of the boundaries and euhedral crystalline uranium mineral grains in biotite pegmatite.Uranium is main composition of the crystalline uranium mineral,then Th and Pb.It is relatively rich in rare element Y and the rare element is closely related to uranium.Further prospecting should be focused on biotite pegmatite within scope of 0-200 m of the outer contact zone of Huichizi pluton.