Optical core scanning in various spectral ranges as applied to study of lithological characteristics of rocks

Abstract

© SGEM2019. Fluorescence analysis is widely used in various scientific fields. It has many practical applications in biology, medicine and chemistry. Geoscientists can benefit from using it as well. For example, hydrocarbon saturation and carbonate content can be measured by illuminating rock samples with ultraviolet light and evaluating the intensity of emitted visible light. The most interesting case is where the wavelength of the released light is greater than that of the incident light. In geology and geophysics, fluorescence analysis may be used to study samples on different scales: From thin sections to full boxes of core. This paper presents a methodology that can be applied to the study of entire boxes of core using an automated optical scanning complex. In addition, spectral reflectivity of samples in ultraviolet and visible light is evaluated, and the process of measuring the fluorescence intensity in visible range is presented. Automated photogrammetric processing of scanning results is performed, resulting in or tho transformed images of core boxes. Methods are also provided for mathematical processing of raster data, which allow identifying various lithological characteristics of the core samples, obtaining hydrocarbon saturation and carbonate content curves and then analyzing them in combination with logging data.