Planning a Waterflood Project in a Mature Oilfield: Phase-1 Development Plan by Integrating Static and Dynamic Modeling of Belimbing Field, Indonesia

Abstract

The Belimbing Field is one of an almost-forgotten-mature field in Indonesia. Discovered in 1955 but the first oil came in 1965 due to remote area and difficulty in facilities handling. Now it’s still producing with limited facilities even though the reservoir can produce more. By the 2014 due to a new 3D seismic exploration survey in this area showing a good prospect, a development field scenarios was built for Belimbing field. One of the productive layers in this field is S, a sandstone member of Talangakar Formation. This layer contributes as a main production reservoir with its primary peak production reached 7000 bopd in 1967. First water injection was conducted in 1997 peripherally in central block of Belimbing. There was a significant increase in pressure and oil gain in the monitor wells. With the last oil recovery factor of 30% indicates that this layer is still has potential to be developed by waterflooding method. The injection well in the eastern block of Belimbing was injected also from 2005 to 2015 showing a good respond indicated by increasing of pressure and production at producer wells. The quality of 3D seicmic data and limitations number of log and core data becomes an obstacle in static and dynamic modeling. The distribution of acoustic impedance (AI) and waveform classification was conducted in order to get the facies and reservoir properties distribution and try to capture more pictures of reservoir heterogeneity. In doing the rock typing, core data from the nearest field were used. One the method that used in this process was performed synthetic relative permeability graphs and capillary pressure curves by using the evaluated productions data. Through the reservoir modelling, the best scenario was chosen: waterflooding with 60-124 acres of 12 inverted five spot patterns for the first Phase of Development. The fullscale waterflooding project will be on 40 to 50 patterns of 60-124 acres inverted five spot. On the other side, this field is also growing because it does still have other layers that will come as a potential oil reservoir in Belimbing. Those layers will also be develop in this First Phase as a primary wells that already puts on waterflood pattern, comes with data acquisition programs with them. Defining the development plan of the oil field should be considered from the beginning. From discovery to development including waterflood as a method to increase the reserves and production should be put on one grand plan.

AAPG Datapages/Search and Discovery Article #90332 © 2018 AAPG International Conference and Exhibition, Cape Town, South Africa, November 4-11, 2018