AVA analysis and interpretation of a carbonate reservoir: northwest Java basin, Indonesia

摘要

A detailed analysis is performed of amplitude vari- ation with angle (AVA) observations in six common- midpoint gathers with reflection points that are over and beside carbonate reefs in the Parigi Formation in the northwest Java basin. Both empirical analysis and full- wavefield modeling of the AVA data suggest that the presence of gas affects AVA by educing the bulk density of the reservoir, decreasing of the overburden V_p/V-s ra- tio and by local attenuation caused by gas sieving through the overlying sediments.