Geoinformatika 2009; 1 : 34-42

NEW ASPECTS IN RECONSTRUCTING DATA OF 3D OBSERVATIONS OF P-WAVES FOR OPTIMIZING AZIMUTHAL ANALYSIS

Nefedkina T.V., Mezentzev E.V., Melikov R.F.

The paper presents results of testing the “sector” AVOA analysis algorithm by model data for conventional narrow azimuth towed streamer 3D data. The algorithm is intended for detection of fracture orientation and density in an oil collector with respect to compressional reflections. It is shown that observations for medium and large offsets are the most informative. The precision of inverse problem solution increases in case source- receiver lines are about normal to fracture orientation. Algorithms and computer programs have been created for reconstruction of data in condition of non-optimum systems of observations. Two algorithms are offered to create missing seismograms. The algorithms are based on 3D DMO (dip-moveout) transformation. The next algorithm approximates observed reflections amplitudes and calculates the amplitudes in empty intervals of azimuths and offsets. Testing the algorithms has showed that data reconstruction increases the precision of determination of fracture orientation by 3°–7°.