METHOD FOR RECONSTRUCTION OF FINE STRUCTURE OF GEOLOGICAL FEATURES AND DIFFERENTIATION THEREOF INTO FRACTURED AND CAVERNOUS

摘要

FIELD: measuring.;SUBSTANCE: invention relates to the field of seismic survey and can be used in searching for petroleum and gas fields with complex carbonate fractured and cavernous reservoirs. The behaviour of reflecting horizons on time sections is analysed based on the standard seismic images of the environment obtained using reflected waves. The angles of inclination of the borders of the target horizons are determined, used to calculate the optimal parameters of the asymmetric summation of seismic data: the angle and azimuth of tracing of Gaussian beams, defining the weight coefficients and the aperture ensuring the most reliable construction of the scattered wave energy field. Asymmetric summation of the seismograms is conducted with the obtained parameters after signal processing and cubing of average velocities. The obtained selective images in the area of inclination angles and azimuths of tracing are summed, and the scattering attributes are calculated from the obtained full-azimuth scattered wave energy field, based on the analysis of the selective images depending on the azimuth and the type of diffraction/scattering, and based on the actual geological and geophysical information present on the area, reconstruction of the fine structure of the geological features and differentiation thereof into cavernous and fractured areas are conducted.;EFFECT: increase in the accuracy and the level of detail of reconstruction of the structure of carbonate reservoirs when identifying and localising fractured and cavernous areas, as well as possibility of differentiating these objects by distinguishing between fracture and cavern concentrations.;1 cl, 5 dwg