Experience in surface hydrocarbon geochemical, gamma-ray spectrometry and magnetic survey on oil field in the Bazhenov Formation

The relevance of the research is caused by insufficient study of the issue of the possibility of applying the ground geochemical and geophysical (non-seismic) methods when searching for hydrocarbon deposits in black shale rock formations. Such deposits with high oil content resource potential of Western Siberia are bituminous mudstones Bazhenov Formation. According to the features of their localization the autochthonous oil accumulations have a number of significant differences from the traditional oil and gas fields, and wellestablished models of epigenetic formation of abnormal geofields are not really relevant for interpreting the geochemical and geophysical survey data in similar geological conditions. Therefore there is a need to assess the information content of these search methods to identify the objects of oil and gas shale type. The paper introduces the results of the geochemical and high-precision ground radiogeochemical and magnetic surveys in the south of Western Siberia. The main aim of the research is to study the structural features of the subsurface hydrocarbon geochemical, radiogeochemical and magnetic fields and their transforms, on the oil field in the Bazhenov Formation. The methods used in the study: ground high-precision magnetic field measurement methods and radiogeochemical fields, laboratory testing of samples for the maintenance of hydrocarbon components, data statistical processing, including filtering methods and the relative parameters of shale oil field in the south of Western Siberia. The results of the research. The authors have evaluated the quantitative relationship and qualitative characteristics of the analyzed geofields with structural-tectonic peculiarities of the territory structure and its oil potential by: the indicators of residual magnetic field, dispersion and gradient of magnetic field; dispersion of radiogeochemical indicators; analysis of changes in the values of hydrocarbon indicator ratios.