Evolution in information on crustal geothermal parameters due to application of advanced experimental basis

Abstract

New experimental basis was developed and implemented to provide improvement in geothermal data reliability and extension of the geothermal data application in geophysics. A continuous thermal core logging technology was developed (2015) and applied (2015-2018) on 27 300 cores from 31 wells. Correlations between thermal and other rock properties, established from integration of thermal and standard logging data, allowed to improve standard logging data quality and estimate thermal properties from standard logging data. New optical scanning instruments provide profiling thermal properties to characterize formation heterogeneity continuously with spatial resolution up to 0.2 mm. International recommendations on rock thermal property measurements were developed. The approaches were developed to improve techniques of thermal property integration in modern hydrodynamic simulators. Techniques were elaborated to determine firstly rock matrix thermal properties and provide fast thermal property measurements on rock cuttings. Rock fracturing characterization became possible from thermal core profiling. Vast data on thermal property at elevated temperatures were obtained with the special instruments. New investigations of vertical variations in heat flow performed with the new technologies confirmed our previous data on heat flow increase with a depth by 45-120 % that requires serious corrections of the previous results and reconstruction of geothermal maps often.