Geological and geostatistical analysis for equivalent uranium and thorium mineralization, Gattar-V Eastern Desert, Egypt

Abstract

Purpose. This paper aims to assess the distribution of uranium and thorium ore grade distribution to produce a uranium potential map and estimate of the uranium ore reserves in the Gattar-V area, Eastern Desert, Egypt. Methods. Multidisciplinary approach is applied to determine the equivalent uranium mineralization in the Gattar-V area. It includes geological (petrographical, mineralogical and geochemical) and geostatistical (kriging analysis and variogram models) methods. Findings. Geological studies show that the U-mineralization located along or near the contact between younger granites and Hammamat sediments exhibits episyenitization and bleaching alteration, respectively. Geochemical studies indicate a strong relationship between U-mineralization and Chemical Alteration Index (CIA), alteration features, and associated hydrothermal solution mineralization. The geostatistical method is used to study the behavior and distribution of U and Th in both younger granites and Hammamat sediments. The Total Gamma, eU, and eTh values are used in kriging analysis and variogram models to determine their spatial dependence and perform a spatial interpolation of sparse measurements and deposition level map. Originality. The use of a multidisciplinary method combining petrographical, mineralogical and geochemical investigations with geostatistical analysis allowed for a quantitative evaluation of the spatial location of geological objects such as uranium mineralization in the area. Practical implications. Variogram models and kriging analysis can also be used to assess the lithological composition of rocks and mineralogical phases, and they also provide a clear vision of the elements distributed in the ore, which is very useful during the planning and production stages.