Influence of seismic acquisition on AVOZ inversion: A case study in Ha7.area of Tarim Basin

摘要

As a crucial metlod to detect fractured carbonate reservoirs in the Tarim Basin, P-wave AVOZ inversion results (fracture density and orientation) are always dominated by original data azimuth range and orientation. However, the relationship between data azimuth and inversion result in practice highly related to financial input has actually not been well verified because of the insufficient research. Benefiting from the full azimuth field data in Ha 7 area, 8 sets of data distribution with different azimuth range and orientation are classified to conduct P-wave AVOZ inversion for comparison. Particularly, the full-azimuth results are taken to establish a criterion of quantitative inversion evaluation. It is found that the predicted anisotropy accuracy enhances with increase of data azimuth range in the same center orientation, while it also improves with the increase of intersection angle (0-90°) between fracture direction and data center orientation under the same azimuth range, which is concluded to be the foremost factor for inversion. Besides, the fractured reservoir can be accurately delineated, approaching the precision of full azimuth data, under the optimized limited azimuth distribution. This research could find its robust value in the acquisition and inversion improvement in the Tarim Basin.