摘要
红石泉铀矿床是以岩浆气成热液成矿作用占主导地位的复成因型铀矿床。研究结果表明,黑云母的结晶时间明显晚于伟晶状白岗岩中的长石、石英等主要造岩矿物,这是由白岗质 岩浆本身的物质成分和物理化学条件所决定的。岩体边缘的黑云母与晶质铀矿同步富集作用是以元素地球化学和矿物热力学作用为主导的地质作用。黑云母与晶质铀矿结晶时间相近,具有一定的成因联系,并且,其组份具有明显的亲缘性是二者密切共生的原因。
The Hongshiquan uranium deposit is a new type uranium deposit recently discovered in China. The host rock—pegmatitic alaskite intruded into metamorphic rocks of the Lower Proterozoic Longshoushan Group. The deposit is a polygenetic one formed as a result of composite metallization of magmatic pneumato-hydrothermal solution mad late ore-bearing hydrothermal solution with the former playing the leading role. From the relationship between the activity of biotite in the magma and the crystallization temperature (T) , i. e., it is considered that the phenomenon that the biotite along the margin of pegmatitic alaskite crystallized obviously later than such rock-forming minerals as feldspar and quartz is attributed to the comparatively small activity of biotite in the alaskitic magma which resulted in the decrease in its crystallization temperature until its crystallization in the magmatic pneumatolyto-hydrothermal stage.The synchronous ernichment of biotite and uraninit is a geological activity with crystallization differentiation of magma, element geochemistry and thermodynamic effects being dominant. According to thermodynamic principles and statistics, the authors consider the reasons for the intimate relation.ship between biotite and uraninite to be as follows. (1) their close crystallization time, (2) the existence of certain genetic relationship and (3) the apparent affinity of biotite and uraninite in composition. The synchronous enrichment of biotite and uraninite depended on composition and physical-chemical conditions of the magma. It is therefore concluded that the biotite concentration zones along the margin of the pegmatitic alaskite are favorable ore-prospecting places.
出处
《岩石矿物学杂志》
CAS
CSCD
1989年第3期242-251,共10页
Acta Petrologica et Mineralogica
关键词
铀矿床
黑云母
晶质铀矿
同步富集
uranium deposit
biotite
uraninite
synchronous enrichment
