Publications

The main reservoirs of the Jatibarang structure consist of naturally fractured volcanic rocks. These volcanic rocks fall into three distinct lithology types: tuff, lava flow and agglomerate. Realistic characterisation of reservoir geometry and physical properties is a problem, as is their quantification since most available logging tools are not designed to detect the properties of fractured reservoir systems.A well log interpretation technique based on the dual porosity concept has been developed for evaluation of the rocks of the Jatibarang formation. So far this technique, which requires calibration of log data with core analysis data, has been applied to the volcanic tuff lithology only, but the results are encouraging and it is believed that the technique can be. satisfactorily entended to the other lithology types.This paper describes the development work carried OUF on the technique to date. A mathematical relationship for characterisation of dual porosity parameters by analysis of conventional well logs has been derived. A 'model' well has been chosen in which an extensive set of log and core data is available. These data have been used to determine the appropriate interpretation coefficients for the Jatibarang Volcanic tuff reservoir lithology.