Perpustakaan Digital ITB

Accurate differentiation of reservoir fluid and determination of elastic parameters when some logs are not available is a major challenge in the petroleum industry and this study explored the potential of rock physics modeling to resolve these challenges. Suite of logs from four wells were provided, but only three wells were used for the analysis because well 3 does not have density log. Petrophysical properties were calculated from the logs using the respective equations and pseudo shear wave velocity was estimated from the P-wave velocity. The result of the rock physics analysis carried out using crossplots of acoustic impedance against P-wave velocity coloured with gamma ray log was able to separate the lithology into sand and shale both within the wells and the reservoirs of interest with the aid of the relevant rock physics models. Vp/Vs against acoustic impedance crossplots coloured with density log indicated the pore fluid in the wells and mapped sand bodies to be water and oil. Two mathematical models for predicting elastic parameters in the absence of some necessary logs were developed and these models can be used in the Niger Delta and in other sedimentary basins of the world.