ABSTRACT: Petrophysical study of the Lemat Formation, Puyuh Field, South Sumatra, Indonesia
Aly, Mohamed A.M.1, Agus Sudarsana2, Ermawan
Maulana2, and David G. Kersey2
(1) Schlumberger GeoQuest, Kuningan - Jakarta, Indonesia
(2) Gulf Indonesia Resources, Jakarta, Indonesia
A Petrophysical study of the LEMAT Formation in the Puyuh Field was undertaken using all available well data. Integration of open hole logs with conventional and sidewall core data, X-ray diffraction, DST and production data lead to a comprehensive description and interpretation of the oil-bearing, LEMAT shaly-sandstone formation.
The main objectives of the study were: 1) Define and establish geological and petrophysical models for the LEMAT formation 2) Calculate porosity and water saturation profiles 3) Establish the permeability distribution for the field. Twelve wells, with complete open hole log data, were processed using Schlumberger's ELAN Plus petrophysical software. In the analysis, the same lithological, and petrophysical model was used, which lead to a consistent interpretation and integrity of the results. The lithological model was defined as a mixture of quartz, feldspar (orthoclase and plagioclase), clay (kaolinite and illite), pyrite and siderite. The final ELAN mineral analysis shows a good comparison with both X-ray diffraction and thin section petrographic data. The resultant ELAN porosity, permeability and grain density evaluation shows a very good match with depth-matched core and sidewall core data. The permeability distribution in the field indicates the reservoir section of the Lemat formation is highly permeable in the oil leg. The water saturation profile helps define the field's original oil-water contact.
The results of the study show the importance of integrating geological and engineering data for improved petrophysical analysis. The match between log-computed parameters with core, DST and production data has provided improved input data for reservoir simulation.
AAPG Search and Discovery Article #90913©2000 AAPG International Conference and Exhibition, Bali, Indonesia