Perpustakaan Digital ITB

Petrophysical interpretation is the hydrocarbon potential determination process using the well borehole data, either the openhole data or the cased-hole data. Considering the availability of variable data sources and measurements, the data used should be able to enhance the petrophysical interpretation technique, hence providing better hydrocarbon potential estimation with minimum deviation. The better petrophysical interpretation can reduce the cost management in hydrocarbon production. This study compares the formation evaluation made by the wireline log data from exploration wells (open-hole data) with the LWD log data from development wells (cased-hole data). This study is also intend to conduct an integrated approach of the open-hole data and the cased-hole data for the petrophysical interpretation at Garuda Field. The main petrophysical properties (porosity, thickness, water saturation and gas saturation) of Beta, Cigma and Delta reservoirs, and the hydrocarbon potential of the study area is also determined using the proposed integrated approach. The petrophysical properties for Beta reservoirs are : porosity 13.90 %, thickness 23.81 meter, water saturation 65.60 % dan gas saturation 34.40 %. The petrophysical properties for Cigma reservoirs are : porosity 20.40 %, thickness 24.23 meter, water saturation 63.00 % and gas saturation 37.00 %. The petrophysical properties for Delta reservoirs are : porosity 19.60 %, thickness 36.44 meter, water saturation 66.80 % and gas saturation 33.20 % The hydrocarbon potential estimation resulted from the integrated approach is 15 % lower than that of the previous estimation. Such approach provides a better hydrocarbon potential estimation, thus can be used for a better Gas Field Development Plan.