Application of gamma-ray spectroscopy and IR-spectroscopy methods for the purposes of ore geology in the Timan-Pechora Oil and Gas Province (the case of Ukhta Region)

Abstract

Two express methods are presented in this paper. The first method is a high-resolution gamma-spectroscopic method based on a germanium detector, the second method is an IR-spectroscopic method. The applied complex of methods allows to determine the sources of uranium and thorium, identify the rhythms of uranium accumulation associated with regional events; identify areas with a high content of uranium due to the influence of local sources (faults, hydrothermal, etc.); determine the amount of authigenous uranium in the composition of total uranium; determine thermal maturity of organic matter in shales without their preliminary demineralization. To identify levels of increased uranium intensity in the high-carbon strata, a set of indicators has been proposed, which includes both applied indicators in practice of geological work and new indicators.New indicators have been tested on the collection of shale reference samples. For them, values were established that characterize the processes of uranium accumulation and uranium removal. On the example of Ukhta Region according to the proposed indicators, the sections from the VendianRiphean to Domanic inclusive were interpreted.The performed work showed the possibility of comparing the calculated gamma-spectroscopic data with the data of other methods. This opens up a broader perspective for the use of express non-destructive gamma-spectroscopic method for detecting levels with a high content of uranium in the shale rocks, to which ore-bearing concentrations of a number of metals are also confined.

Keywords

• uranium
• thorium
• domanic suite
• shale
• kaolinite clays
• gamma-spectroscopy
• ir-spectroscopy
• neutron activation method
• method of chromatography-massspectrometry data with inductively coupled plasma (icp ms)