THE RELEVANCE OF CORE SAMPLING IN GEOLOGICAL AND TECHNOLOGICAL STUDIES OF WELLS, THE IMPACT ON THE CORRELATION AND REFINEMENT OF FILTRATION AND CAPACITIVE PROPERTIES OF RESERVOIR FORMATIONS OF THE KAMYSHNYANSKY GCF

Abstract

Drilling of deep exploratory and appraisal wells in long-developed fields is made possible by the use of modernized heavy-duty drilling rigs and state-of-the-art geophysical equipment for conducting industrial-geophysical studies in both open and cased wellbores. This leads to improved research quality. These wells are designed to reach depths greater than 6,500 meters. The proportion of 3D seismic surveys and vertical seismic profiling in wells is increasing, allowing for more accurate definition of the surrounding borehole environment, reservoir potential, and precise planning of subsequent wells. During the drilling process, geological and technological studies (GTS) are carried out, forming an integral part of well geophysical surveys (WGS). The initially collected material serves as the fundamental source of geological information about the well section, allowing for correlation with design data, neighboring wells, and refinement of geological models. The relevance of core sampling using core barrels during drilling is emphasized, as it helps determine and refine the filtration and storage properties (FSP) of reservoir rocks based on the retrieved core. These data are then applied in building correlation schemes for drilled wells in conjunction with industrial-geophysical survey data.In exploratory and appraisal wells, this is especially important: the greater the sampling interval, the higher the quality of geological section information, identification of hydrocarbon-saturated intervals, and determination of their characteristics.Through integrated methods along with WGS, hydrocarbon-bearing intervals are identified and stratigraphic horizons are precisely tied. The analysis of geological and geochemical data from cuttings and cores complements the justification of fluid saturation in reservoir rocks. In cases where a full set of industrial-geophysical studies cannot be performed due to borehole complications or risk of borehole loss, making fluid saturation difficult to assess, such analysis becomes a significant factor in identifying the prospectivity of the horizon.