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东外贝加尔地区的图鲁库伊破火山口属于富氟和亲石元素(U、Mo、Li、Be、Sn和W)的高硅亚碱性岩浆喷发时形成的火山构造,其中集中着斯特列措夫矿田的许多铀矿床。这种破火山口是遭受拉张和裂谷作用形成的陆内活化区典型的构造。从共结熔浆中析出的流体的性质能够决定交代矿化和脉状矿化的特点——缺乏超酸型交代岩以及矿田的某些矿床上细脉-交代钠长石化广泛发育等。 已经查明四种类型的矿前交代岩:石英-碳酸盐-水云母交代岩,石英-碳酸盐-绢云母(接近黄铁绢英岩的)交代岩,石英-碳酸盐-高岭石交代岩以及蒙脱石和沸石-蒙脱石交代岩,还有矿后泥化交代岩。发现矿前交代岩的分布与破火山口火山断块构造有关。在其最隆起(和富矿)的东部火山断块中,水云母交代岩和黄铁绢英岩发育,在较下凹的中央火山断块和局部地在西部火山断块中——泥化岩石发育,其分布与火山颈相酸性火山岩相吻合。最晚的矿后泥化岩石分布普遍,它们与破火山口的内部构造无关。
The Tulukuayi caldera in the eastern Baikal region belongs to a volcanic tectonic setting formed during the high-silicate alkaline magmatic eruption of fluorine-rich and lithophile elements (U, Mo, Li, Be, Sn and W) Many uranium deposits in the Lechov ore field. This caldera is a typical structure of an intracontinental activation zone that is exposed by tension and rifting. The nature of the fluids precipitated from the co-brazing fluid can determine the characteristics of metasomatism and vein mineralization - the lack of super-acid metasomatism and the presence of fine veins in some deposits of the orefield - the extensive development of metasomatism. Four types of pre-metasomatists have been identified: quartz-carbonate-hydromonic metasomatism, quartz-carbonate-sericite (proximate to pyroxene), quartz- carbonate- kaolinite Metamorphic rocks, as well as montmorillonite and zeolite-montmorillonite metasomatism, as well as post-oremization metasomatism. It is found that the distribution of pre-ore metamorphic rocks is related to the structure of the volcano faulted block in the caldera. In the eastern volcanic faulted blocks of its most uplifted (and rich) ore, hydromonitic metamorphic rocks and pyritic sericite developed. In the more depressed central volcanic fault blocks and locally in western volcanic fault blocks - the development of muddy rocks, Its distribution coincides with volcanic neck facies acid volcanic rocks. The latest post-mining muddy rocks are widespread and have nothing to do with the internal structure of the caldera.