| Introduction of the author:Zhangxiang, male, was born in June,1991whosetutor was Professor Zhengqi,Xu He graduated from Chengdu University ofTechnology in Geochemisty major and was granted the Master Degree in June,2014.Southwest region is an important carbon silicon mudstone type uranium oreconcentration area, and has found a series of ore deposits and mineralization points.Based on summarizing and analyzing a large number of data previous, select fourtypical deposits as the key research object, and study the geological characteristicsof ore deposit and geochemical characteristics in detail, to establish thecorresponding carbon silicon mudstone type uranium metallogenic model, andthrough the contrast research to understand and have achieved the following results:Uranium mineralization is controlled by structure and lithology formation.Fault and its secondary fault also interlayer fracture zone provides the migration andreservoir space for the ore deposit formation. The structure of the uraniummineralization degree in high degree of crushing and lithology complex is higher.The formation which rich in shale, siliceous and the organic matter has anadsorption for uranium and conducive to the formation of ore deposits. Theformation of deep fault which Communicated Early Devonian system is conduciveto mineralization enrichment. ore bodies main in bedded and lenticular, controlledby the structure. The underlying attitude and tectonic fracture zone is consistent inoccurrence.Sedimentary environment are shelf sea anoxic,forming a favorable lithologycombination. The sedimentation of hot water has effected sedimentary processobviously, and is helpful to form uranium enrichment of strata. Wall rock alterationhas the similarity, mainly include silicification, pyritization, dolomitization, calcite. Surrounding the mining area have diabasic dike exposed. The formation of oredeposits are affected by a certain hydrothermal activity.Ore deposit has typical characteristics of hydrothermal enrichmentcharacteristics of elements, rare earth element distribution patterns are relativelylight rare earth elements, the characteristics of the distribution pattern to the right. Atthe same time, the composition of trace elements and rare earth elementscomposition of ore and rock almost same, illustrates the consistency of its source.Uranium source mainly comes from the formation.Carbon and oxygen isotopic values is relatively close, the δ13CPDBof Daxindeposit δ13CPDBrange is-2.78‰~0.68‰, the δ13CPDBof Bajiang river’s depositδ13CPDBrange is-2.30‰~-0.34‰, the δ13CPDBof LeiTun deposit δ13CPDBrange is-2.30‰~-0.34‰.All revealed belong to carbonate area, but have the features ofhydrothermal characteristics.Ore-forming fluid should mainly belongs to the atmospheric precipitation alongthe formation and fault leaching infiltration, and hybrid storage of ancient waterwith deep formation water in the stratum, under the mixed action of the tectonichydrothermal heating form hot water, and along the fault rise, on the way to extracthydrothermal fluid of activated uranium formation, meanwhile may have deep fluidinvolved.Summarizes the regional uranium mineralization in three steps: Sedimentarydiagenetic stage uranium pre-enrichment, the late tectonic movement formedmigration channel and reservoir space, hydrothermal superimposed mineralization.Pointed out the area of the next step prospecting direction of the uranium depositprospecting... |
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