航空伽玛能谱数据在扎兰屯地区铀成矿预测中的应用

Application of airborne gamma energy spectral data to uranium metallogenic prognosis in Zhalantun area

受森林分布广、覆盖厚及矿体隐伏等因素制约,大兴安岭成矿带扎兰屯地区铀矿找矿进展缓慢。航空伽玛能谱数据蕴含有丰富的铀矿化信息,除地表矿化信息外,亦含有部分深部铀矿化弱信息。文章在对扎兰屯地区典型铀矿点成矿地质特征及伽玛能谱特征分析的基础上,利用K、U、Th元素含量之间的地球化学特征差异,构建了2个航放参数模型(ΔU高值晕、F高值晕),增强航放微弱异常信息;在航放异常信息提取、优选的基础上,结合地质、化探等找矿有利信息,预测铀成矿远景区7处;其中2处远景区成矿地质条件优越,异常线索丰富,尚属铀矿空白区,在进一步工作中应引起重视。

Due to wide spread forest,thick cover and the buried ore body uranium prospecting in the Zhalantun area of the Daxing’anling metallogenic belt has not made breakthropugh.The airborne gamma energy spectrum data contains aboundant information on uranium mineralization.In addition to surface uranium mineralization information it also contains the weak information to depth.Based on the analysis of metallogenic geological characteristics and gamma-ray spectrum characteristics of typical uranium deposits,two airborne radiactive parameter models(ΔU high value halo,F high value halo)were constructed by variation of K、U、Th contents to enhance the weak anomaly information of airborne radioactivity.On the basis of extracting and optimizing the aerial radioactivity anomaly information and combining with favorable information of geology and geochemical prospecting,seven uranium metallogenic prospects are predicted.Among them,two prospective areas have superior geological conditions and abundant anomaly clues.They are still blank areas of uranium deposits and should be paid more attention in further work.