Detailing the pore structure of productive intervals within oil wells using 3D color imaging

Abstract

The article describes an approach to the expansion of the methodology for applying hydraulic fracturing in oil fields by adding the possibilities of 3D modeling with color imaging of the pore structure within productive intervals of the wells. As an applied example, the geological and geophysical section of the productive level of one of the wells in Moscudinskoye oil field with known data on the integrated interpretation of the results of well logging and microcomputer tomography was chosen. According to well-logging data, the productive reservoir in the analyzed area of the section is characterized by a high degree of heterogeneity. The tomography studies of a full-size core enabled to identify four lithotypes here with different pore structure features. The consideration of the identified reservoir heterogeneity, as well as the data on the thickness and other characteristics of reservoir properties of individual lithotypes which make up the section, allowed to significantly increasing the detail of the final geological model of the wellbore section. A distinctive feature of this final geological model is the use of the method of enlargement of the initial data array by adding intermediate values which were calculated theoretically. The visibility of the final geological model of the borehole walls is provided by color 3D imaging of the calculated data of the enlarged massif and gives an idea on the presence of areas with good and weak fluid conductivity on the lateral surface of the borehole walls. According to this model, the intrastratal transverse and longitudinal fluid-conducting “corridors” are observed in the circumwell zone that define the hydro-dynamic movements of natural and artificial fluids in the medium of productive reservoirs.