Time Lapse Production Allocation Using Oil Fingerprinting for Production Optimization in Deepwater Gulf Mexico

The variety and sophistication of upstream technologies have been growing fast for imaging the subsurface, modeling reservoir performance and monitoring oil and gas production. Yet there remains a fundamental need to thoroughly sample and analyze the produced reservoir fluids. Reservoir fluid analysis is critical for understanding the nature of produced hydrocarbons and is the key for production optimization. To gain the maximum value from this analysis, reservoir fluid sampling programs need to be well designed and integrated into well testing and reservoir surveillance programs, and not to be developed after. In one of Chevron's deep-water Gulf of Mexico (DWGOM) sub-salt fields, a robust geochemical sampling plan and production monitoring program has been in place since initial production to estimate the zonal contribution from individually stacked reservoirs. This surveillance work has been ongoing for 9 commingled wells over a period of 10 years. This paper presents the accuracy of time lapsed production geochemistry allocation and how the results can substantially impact and improve reservoir characterization and trouble shoot completion issues