THE METHOD TO REMOVE COAL SEAM′S INFLUENCE ON OIL RESERVOIR PREDICTION: A CASE FROM THE BINCHANG AREA

Two kinds of interference are observed in the study of the Yanan Formation coal seam and its influence on the Yanchang Formation reservoir. One is the reflection shielding of seismic waves caused by the strong reflection of coal seams, which made the amplitude of the reflection wave in the deeper sequences weaker; the other is the multiple waves caused by the multiple sets of coal seams, which seriously affect the accuracy of data interpretation and bring catastrophic consequences to the seismic data. By fitting the thickness of the coal seam with the amplitude attribute of the coal seam and predicting the thickness of the coal seam in the whole area, this paper used the wavelet decomposition and the waveform decomposition method, and compared the plane characteristics of the first, second, third and forth components and their coincidence with the drilling wells through a reasonable control of time window. Results confirm that the method seems quite effective to eliminate the influence of coal seams to seismic data in the Binchang area.