钍归一化在盆地γ能谱资料处理中的应用

在应用γ能谱资料寻找砂岩型铀矿的过程中,要尽可能地消除非矿化因素引起的干扰,提取与铀矿化有关的信息。介绍了钍归一化的原理及特点,采用与矿化有关的元素迁移信息的钍归一化方法,分析了二连盆地东部的γ能谱资料,揭示了该区放射性元素的分布特征、地球化学作用和后期铀元素的迁移与富集。结合其他地质资料,分析了钾剩差的变异区(正、负高值区)及铀剩差正高值区形成的原因,同时指出了经过钍归一化处理所得到的铀剩差正高值区应为氧化与还原作用过渡带的直接指示,也是该区进一步寻找砂岩型铀矿的重要标志。

Application on Th normalization for basin gamma spectrometry data processing

In procedure of using gamma spectrometry data to explore sandstone-type uranium deposits,interference caused by non-mineralization factor should be eliminated as clean as possible, so as to extract information on uranium mineralization.In this paper,the principle and characteristics of Th normalization are introduced by using Th normalization techniques which relate to mineralization with information on element migration.Gamma spectrometry data in the east of the Erlian Basin are also analyzed;the distributive characteristic of radioactive element in the area,geochemical process, later stage migration and enrichment of uranium element are revealed.Based on other geological informations,the forming mechanism of residual potassium anomaly region(the highly positive and negative region)and highly positive residual uranium deviation region is analyzed.At the same time, it is shown that the highly positive residual uranium deviation region obtained by Th normalization can be used as a direct indicator for redox transitional zone,and it is also an important symbol to further exploration of sandstone-type uranium deposits in the area.