Reef and Sand Reservoir Appraisal in Well-Absent Place: A Case Study in a Marine Area

The inspiring but indeterminate scenery, that the reef extensively developed in our researching area with obvious bright-spot reflection and distinct seismic velocity drop could be filled by favorable gas, and the blurry reflections below the reef may correspond to periods of turbidity sand reservoir, needs to be more precisely and carefully appraised for further exploration with no hesitation. However, AVO inversion can not be efficiently applied in this unexploited place due to wells insufficiency, even though it is recognized as an excellent method for reservoir prediction and famous of its inverted real P-wave result and other abundant elastic attributes. To efficiently appraise the reservoir quality in this area, an advanced well-absent AVO inversion method, which constructs pseudo-wells according to the seismic interval velocity, amplitude and known message, is put forward and successfully applied in this paper. It is the first time to reasonably appraise the reservoir quality in our working area. The new well-absent inversion method could overcome the prediction obstacles in the early phase of exploration, and suitable for offshore exploration.