METHOD FOR VOLUMETRIC RADIO-WAVE GEOINTROSCOPY OF ROCKS IN INTER-WELL SPACE Russian patent published in 2020 - IPC G01V3/30 

FIELD: geophysics.

SUBSTANCE: invention relates to means of inter-well geophysical investigations, in particular to methods for measurement, processing and interpretation of radio-wave cross-well and borehole-ground screening data. Summary: at least three wells located in nodes of triangular network are used. Optimum operating frequency of emitter and receiver is selected in accordance with design value of diameter of Fresnel zone at specified distance between radiator and receiver and specified average value of specific electrical resistance of rocks. Radio-wave screening of space between each pair of wells by emitter and receiver is carried out according to fan circuit with preset screening step. Tuning antenna is tuned to resonance at each screening step. Measuring data including values of the axial component of the electric field at the receiver, current values on the radiator antenna and active resistance at its output are recorded. All measured values of axial component of electric field are brought to one value of current in antenna of emitter. Mathematical division of inter-well space into elementary cells is performed, shape and dimensions of which are determined proceeding from measurement geometry and Fresnel zone diameter. Simultaneous processing of measurement data is carried out on all cross-sections of radio-wave screening with calculation of values of effective electric resistance of each elementary cell. Based on the results of the measurement data processing, a volumetric geoelectric map of the investigated inter-well space is constructed, which is a three-dimensional matrix based on three coordinates of elementary cells in space and the value of specific electric resistance of each such cell.

EFFECT: high accuracy of localizing and determining properties of inhomogeneities occurring in the space between the emitter and the receiver.

5 cl, 6 dwg