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巴音戈壁盆塔木素地区砂岩型铀矿目的层普遍固结,矿体多层但连续性差,分布不规律,后生改造特征明显。本文通过野外露头调查、岩芯观察和微观分析,发现该地区普遍发育穿层脉状石膏或方解石、热液金属硫化物矿物、矿物重结晶与新生胶结物等,出现硫酸盐-金属硫化物共生矿物和S同位素分馏,指示存在后生热流体活动。通过对矿体、矿石特征及铀矿物成因的分析,初步认为热改造对成矿控制主要发生在层间氧化作用后期,温度升高造成碳酸钙和硫酸钙沉淀、重结晶,破坏含矿溶液中碳酸铀酰络合物的平衡,造成U的沉淀,促使铀矿化进一步富集。
Bayinge basin basin The target layer of sandstone-type uranium deposits in Tarim area is generally consolidated. The multi-layer ore body has poor continuity, irregular distribution and obvious retrogressive transformation. Through outcrop investigation, core observation and microscopic analysis, it is found that there are widespread occurrences of through-layer gypsum or calcite, hydrothermal metal sulfide minerals, mineral recrystallization and nascent cementation in the area, and the occurrence of sulfate-metal sulfide symbiosis Fractionation of mineral and S isotopes indicates the presence of post-thermogenic fluid activity. Based on the analysis of the characteristics of ore bodies and ore and the genesis of uranium minerals, it is preliminarily believed that the thermal alteration mainly controls the mineralization in the later stage of interlayer oxidation. The increase of temperature causes precipitation of calcium carbonate and calcium sulfate, recrystallization and destruction of ore-bearing solution Uranyl carbonate complex equilibrium, resulting in U precipitation, prompting uranium mineralization further enrichment.