斯特列利措夫矿田一个大型-超大型铀矿床群在苏联时期是怎样被发现和被勘探的

斯特列利措夫（简称Str）矿田是一个主要由大型-超大型钼铀矿床构成的矿床群，它位于南滨额尔古纳地区，铀的总储量在25万t以上，平均品位0.20%。该矿田在苏联解体以来的很长时间内几乎是俄罗斯唯一的天然铀来源。该区找铀的工作历程漫长而曲折，并颇具传奇色彩。早在1948年苏联地质部第一局松林大队在南滨额尔古纳地区开始了找铀工作。但因区内几乎所有矿床均属盲矿，而且多埋深较大，1962年之前找铀无果，1962年春已决定放弃在该区进行的找铀工作。1962年夏天高级地质师Л П伊舒科娃参观了哈萨克斯坦产在酸性火山岩中2个规模不大的铀矿床（波统-布鲁姆和克泽尔-萨伊），注意到斯特列利措夫萤石脉围岩霏细岩的蚀变与哈萨克斯坦2个规模不大的铀矿床相似。归来之后，她上书领导力主恢复本区找矿工作并获得了再去做最后一试的机会。1963年5月，伊舒科娃所设计的钻孔一箭中的，发现了首个Str超大型铀矿床，整个局面立刻出现大转折，加速矿田开发成了所有工作的总方针。矿床的普查勘探工作和对矿床的地质研究工作平行加速进行，两者互相促进。不到10年，矿田的大部分矿床被一一发现；到1966年底，Str等矿床的初勘成果已经成为1970年代初组建全苏最大铀矿山的充分依据。到1980年底，矿田已有17个钼铀矿床完成勘探。1992年底19个矿床勘探完成。新一轮找矿采用的方略：首先合理综合运用地质、放射性及传统地球物理和地球化学方法，并合理综合使用深度普查自动装置射孔和钻探手段，进行不同比例尺的立体地质-构造填图；然后在其成果的基础上用钻孔去发现矿体。勘探工作所面对的基本事实：矿床构成的多重复杂性为Str矿田内所有矿床的共同特征；每个矿床的特点各异，其勘探过程不尽相同。初勘使用地表钻探进行，基本网度200 m×100 m~400 m×100 m。详勘使用坑探工程与钻探相结合的手段，采用水平与垂直断面联合的勘探系统，基本网度50 m×20 m~50 m×25 m。所有矿床的勘探成果完全被开采工程证实，并有10%的储量增长。Str铀矿床形成于晚中生代，为区域构造-岩浆活化作用晚阶段的陆相火山作用地区的岩浆热液矿床，受断裂构造控制是其基本特征之一。铀矿床在矿田内空间定位的重要规律：Str及其他绝大多数铀矿床均受控于南北向、北西向或东西向断裂与北东向额尔古纳隐伏深断裂带交汇。"斯特列利措夫效应"曾迅速地在我国铀矿地质勘查工作中传播，期待在我国，尤其在呼伦贝尔，乃至大兴安岭-燕山山脉中生代构造-岩浆带地区继续发酵，取得更多和更大的成果。

How Was a Large-Superlarge Uranium Deposit Cluster Discovered and Explored in Streltsov Ore Field in Soviet Union

Streltsov (Str) ore field is a large deposit cluster composed of super-large and large Mo-U deposits, and has been the only source of natural uranium in Russia for a long time after the disintegration of the Soviet Union. Its discovery and exploration in Str ore field is long, tortuous, and legendary. The uranium prospecting began in the region of South Erguna, and stopped completely at the beginning of 1962, as no valuable results had been found. In the autumn of 1962, L P Ishukova, a senior geologist, wrote to the leader suggesting a continue prospecting work in this area, and got the chance to try again. The first super-sized U deposit was discovered by her drilling layout in Str ore field, and caused the big turn of the whole situation. Since then, accelerating the ore field development had become the general principle of all work. The parallel acceleration of exploration and geological research for deposits promoted mutually, and most of the deposits in this ore field were discovered within the following 10 years. By the end of 1966, the preliminary prospecting results of Str and other deposits had become a sufficient basis for the establishment of the largest uranium mine in the Soviet Union in the early 1970s. By the end of 1980s,17 Mo-U deposits had been completely explored. From a technical perspective,the success of Str ore field exploitation has two main reasons:one is that people have had a deep understanding to these deposits and their control conditions in the ore field; the other is that the work methodology adopted has been improved constantly, as almost every deposit in this ore field is a deep-buried blind ore. The new round prospecting strategy was that by the comprehensive use of geology, radioactivity, traditional geophysics, geochemistry, deep survey automatic perforation device, and drilling exploration, three dimensional geological tectonic mapping of different scales was completed. On the basis of these results, drilling was used to discover deposits. The basic fact facing exploration work is that the complexity of deposit composition is the common feature of all the deposits in Str ore field, and each deposit has its own characteristics, which makes every exploration process of these deposits quite different. Drilling was used in early exploration, and the basic mesh ranged from 200 m×100 m to 400m×100 m. In detailed exploration, the combination of underground engineering and drilling was used, and the exploration system combined with horizontal and vertical cross sections was adopted with the basic mesh from 50 m×20 m to 50 m×25 m. The total exploration results of all deposits were fully confirmed thereafter by mining engineering, and the reserves was also increased by 10 percent. The basic experience and lessons of the successful exploration in this field are worthy to learn. The "Str effect" has spread rapidly in China for geological exploration work. It is expected to continue to ferment in China, especially in Hulun Buir, and even in the Mesozoic tectonic-magmatic belt of the Dahingan-Yanshan Mountains with more and greater achievements.