Seismic response characteristics of rich reservoir in M depression

Fluid in rock pores is one of the most important reasons that cause seismic response changes. But the property of oil is similar to that of water within one interbed. This may result in a too small difference of seismic response characteristic between the oil-saturated layer and water-saturated layer so that they cannot be identified. Based on prior well logging and drilling data in M depression region, we have found that thin sandstone and mudstone interbed reservoir with high thickness ratios of oil layers and total layers has strong reflection events on seismic sections. And this pattern has been verified by the forward modeling of the reservoirs models with different thickness ratio of oil layers and total layers. On this basis, the various post-stack attributes are extracted for quantifying seismic response characteristics of rich oil reservoir. By implementing the statistic analysis to the attributes of real seismic section, we have found that the rich oil reservoirs have bigger variation of seismic response characteristics in some local region of this depression area, where owns stable sedimentary facies and gentle structure. This method may provide a robust tool for identifying the rich oil reservoir.