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Terbatas Suharsiyah

This study discusses methods to develop low resistivity, low contrast (LRLC) formation in Indonesia. LRLC formations were found throughout Talang Akar formation but were initially interpreted as non-productive formations. This study focuses on the development of LRLC zones, through the use of horizontal well, 5-spot well patern and water injection, these zones could be developed economically. Reservoir simulation is conducted on field X within 20 years of production period to forecast how effective horizontal well and water injection to improve the oil recovery factor in a low permeability reservoir. Thus, sensitivity studies were created to find the optimum recovery factor by varying operational parameter (i.e., water injection rates). The author varies the water injection rate from 500 bbl/d to 3000 bbl/d. Those numbers are chosen because the initial total production oil rate is 2000 bbl/d. After the reservoir simulation has been done in CMG, the base case without water injection results cumulative oil production for 20 years is 993.67 MSTB (Recovery Factor = 46%) for one pattern. For the best technical is with 2000 bbl/d water injection rate which produces 1322.07 MSTB (Recovery Factor = 61.24%). The most profitable scenario is also acquired when the water injection rate is 2000 bbl/d. This scenario could give the Net Present Value at a 10 percent discount rate of $ 18,309,909.71 and IRR of 54%.