Integration of time-lapse geochemistry with well logging and seismic to monitor dynamic reservoir fluid communication: Auger field case-study, deep water Gulf of Mexico

Abstract

AbstractThe present study illustrates the multi-disciplinary integration of time-lapse geochemistry with 4D seismic, production logging and pressure history analysis in the Auger Blue reservoirs. The integrated approach enables identification of dynamic fluid reservoir communication occurring after six years of primary production between an oil (Lower Blue O2) and a gas reservoir (Blue O Massive) indicated by pressure data as separate at static conditions, and points to cross-fault leakage with possible stratigraphic communication as the likely mechanism(s) by which dynamic fluid reservoir communication has occurred.The time-lapse geochemistry study was performed utilizing fluid samples collected during a period of over eight years of primary production. The results present evidence for gradual mixing of Lower Blue O2 oil with the condensates of the Blue O Massive reservoir. Time-lapse geochemistry results also pinpointed the timing when dynamic reservoir communication started to occur, with an initial mixing detected as early as six years after the start of production. Statistical evaluation of the geochemistry results showed the contribution of the oil to the gas condensate reservoir to significantly increase from 14–23% to 60–63% within a year from when mixing was initially detected. The results of the study assisted in implementing an improved field development strategy to increase production.