中文摘要:本文对暗色岩脉与铀成矿关系在铀成矿的源-运-储三方面进行了较为深入的研究。结果表明，暗色岩脉对铀成矿所起的作用主要是提供有利于铀沉淀富集的场所。岩脉的铀含量数倍于同类岩石是花岗岩地区暗色岩脉的特点，但不代表暗色岩脉能够为铀成矿提供铀源。根据暗色岩脉富含挥发分、所代表的岩浆活动与铀成矿作用最接近、成脉与成矿构造上的关联性以及暗色岩脉是深部岩浆浅部表现形式的成因特点，认为暗色岩脉所代表的岩浆活动、构造运动还可以为铀从花岗岩中的活化转移创造有利条件，岩脉的侵入作用虽然对围岩具有一定的加热作用，但还不能成为铀成矿的主要热源。
Abstract:Urannum deposits related to dark dykes are rather common and typical in uranium-bearing granite of Nanling region. This sort of deposits belong to mesothermal-epithermal type and are distinguished from other types by simple mineral assemblage and higher industrial grade. This paper makes a fairly thorough study on the relationship between the dark dyke and the uranium mineralizatlon in three aspects of the ore-forming process, i.e., source materials, transportation and deposition. Studies on uranium content of dark dykes demonstrate that dark dykes from S area, I area, uranium-bearing granite and uranium-barren granite do not show obvious difference in uranium content. This fact, combined with metallogenic characters of this type of deposits, leads to the conclution that it was quite impossible for dark dykes to provide uranium mintralization with source materials. Based on the fact that dark dykes are rich in volatiles, that their magmatic activity is close to uranium mineralization in time, that dykes are tectonically related to uranium deposits, and that the genetic features of dykes are manifestations of magmatic activity at depth, it is considered that the magmatic activity and tectonic movement represented by dark dykes might have created a favorable condition for mobilization and transference of uranium from granite. Though playing some heating role, the invasion of dark dykes could not act as the main heat source for uranium mineralization. Studies show that the major role played by dark dykes in the process of uranium mineralization seethed to provide favorable places for the deposition of uranium. The enrichment and precipitation of uranium in dark dykes are mainly attributed to the “boundary effect” between the dark dyke and granite caused by physical-chemical difference between the two sorts of rocks. The determination along a section shows that ?Eh value of dark dykes is much lower than that of granite, i.e., it decreases abruptly from -20mV in granite to -40mV in dark dykes. Considering the existence of such reducing gases as H2S, CH4 and CO in the dykes, the actual ?Eh value difference should be much greater than that observed. It is therefore conceivable that when uranium-bearing hydrothermal fluids passed through dark dykes from granite, the abrupt change in physical-chemical condition must have resulted in the reduction of U6+to U4+and caused uranium precipitation and mineralization.
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王学成，章邦桐，张祖还.1991.暗色岩脉与铀成矿关系研究[J].矿床地质,10(4):359~370.1991.A Study Of The Relationship Between The Dark Dyke And The Uranium Mineralization[J].Mineral Deposits10(4):359~370
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