Integrated Approach to Decipher Reservoir Fluids Processes and Monitor Production in the Tornado Development, Gulf of Mexico

Abstract

Reservoir grading and connectivity is one of the most important questions facing any field development team in planning production of oil/gas fields. We present an integrated study, including downhole fluids analysis (DFA), physical fluids properties measurements, phase behaviour, and geochemical analyses, to shed light on vertical and lateral gradients in Tornado development in the northern GOM. Results will be presented from initial two wells drilled in 2016, additional development wells in 2017 and time-laps production from the main B6 reservoir over a period of >18 months. The overall set of more than 20 discrete fluid samples from B5, B6, B7 reservoirs and 4 wells went through comprehensive evaluation, including compositional analyses of both gas and liquids, sulfur content, nickel and vanadium, density, viscosity, comprehensive phase behaviour, gas isotopes, biomarkers and flow assurance behaviour. In addition a set of mud gas data collected on the wells in 2017 was used to support the reservoir continuity assessment with wells drilled in 2016. Apart from the overall assessment of fluids distribution for the vertical and lateral continuity/gradients, we will present time-lapse geochemical approach to monitor changes in production from the B6 reservoir since start of production. We will not only show the reservoir architecture and fluids properties distribution in the Tornado wells, but will put in the larger context of the Phoenix field and neighbouring analogue (Bullwinkle). The work presented advances further fundamental understanding of fluids distribution in the diverse Gulf of Mexico petroleum system, and is one of rare cases systematically documenting detailed description of reservoir fluids properties on the field scale, with emphasis on the role of gradients.

AAPG Datapages/Search and Discovery Article #90323 ©2018 AAPG Annual Convention and Exhibition, Salt Lake City, Utah, May 20-23, 2018