Mature fields provide limited option forreserve expansion. The developments are challenging as remaining reservoirsneed more technologically advanced handling. VMC field, have been producing since1986, is now meeting the remark of mature field. Past activity on the field,however, has left some unfavorable pay zone undeveloped.
One of such zone isthe V56 reservoir, with average resistivity log reading only score 3 ohm. DrillStem testing result indicates the reservoir also has low permeability. This reservoir wasproduced commingled with V54 sand which had better permeability. The productiondata, however, indicated no performance differences whether or not it iscommingled with V56. Further test shows there is no reservoir pressure decreaseon V56 reservoir. Hence, V56 reservoir are developed using hydraulic fracturingin accordance to the result.
This paperwill focus on analyzing V56 reservoir development project especially itsreservoir characteristic, production improvement scheme, reserves estimation,and future development. Well log review is used for reservoirdescription along with Drill Stem Test result. Production improvement isachieved through sensitivity test on three schemes: hydraulic fracturing, gaslifting, and hydraulic fracturing combined with gas lifting. The previousanalysis guides the design of the hydraulic fracturing to improve the reservoirproductivity also to add new reserves in VMC-field.
Volumetric method isapplied to calculate the original oil in place (OOIP) of the V56 massiveformation.The V56 log from base to midway upcharacterized as a coarsening upwards combined with amalgamated fining upwardsequence toward the top of the sand. The V56 sand has thickness up to 200 feetnear the base of the massive formation. It is characterized as fine to veryfine grain size sand, thin chlorite clay lamina 0.02″ to 0.2″ thick, silt-sizesediments, and a significant amount of glauconitic mineral.
These characters respondto low resistivity reading on 3 ohm-m. The DST indicated low permeability sandabout 8 md. Sensitivity test for each case provide incremental production of1020 BOPD, 490 BOPD, and 1127 BOPD respectively. Reserves calculation resultsin 16.4 MMBO for 1P volumes.This study may give a new comparison on lowresistivity pay zone development. Thorough data interpretation and detailed strategyplanning are essential. Experience in this operation provide insights forfuture infill drilling programs where hydraulic fracturing treatment isrequired to enhance hydrocarbon production.
