One of the ways to increase the efficiency of oil and gas prospecting is the integration of geophysical methods (seismic and electrical prospecting) with geochemical studies at different stages of geological prospecting.
Particularly relevant is the problem of integrating the methods to complex geological conditions of the sedimentary section (confinement of hydrocarbon deposits to non-anticlinal-type traprocks and mosaic type of reservoirs), which complicates the forecast and mapping of oil and gas targets. Therefore, there is a need to improve oil prospecting methods and increase the efficiency and reliability of prospecting for hydrocarbon accumulation by expanding geological tasks, applying modern innovative solutions, and new research technologies. Taking into account that target horizons (reservoirs-collectors) are traced and mapped by geophysical methods and traprocks (objects) favorable for hydrocarbon accumulations are set, then the possibility of a “direct” forecast and delineation of oil and gas accumulation zones and HC deposits with the definition of their phase saturation and preservation conditions emerges when geochemical methods are included in the geophysical complex.
Currently, the forecast and prospecting for oil and gas are carried out based on a comprehensive study of the geophysical and geochemical parameters of the sedimentary section, based on the interconnection and interdependence of geochemical and geophysical fields in space and time, and most manifested in the phenomenon of paragenesis of zonal-annular anomalies in geochemical and geophysical fields over hydrocarbon deposits. It is assumed that geochemical conditions of the environment, as well as their features (the material composition of rocks and fluids containing them), predetermine the physical properties of the sedimentary section containing HC accumulations.
Identification of the oil-prospecting traprock with a complex of CMP seismic survey, electrical reconnaissance of near-field time-domain electromagnetic sounding, and lithogeochemistry (Angara-Lenskaya oil and gas-bearing region)