Jason R . McKenna and David D . Blackwell 3 - D Multiphysics Modeling of a Producing Hydrocarbon Field

Thermal anomalies indicating elevated temperatures often are present in producing hydrocarbon fields. Thermal anomalies delineated by bottom hole temperatures (BHTs) are readily identified in such settings, but are difficult to interpret because the data are not equilibriumtemperature measurements, nor do they provide depth constraints on thermal anomalies (i.e., change in heat flow with depth, fluid migration, etc.). A better method to investigate the source and spatial extent of thermal anomalies (or even the background thermal regime) is with precision temperature logs, which can then be utilized to constrain subsequent modeling efforts. This paper discusses precision temperature logs obtained over a salt dome in the Bayou Bleu hydrocarbon field in southwest Lousiana, and presents a 3-D thermal-fluid model of the dome constrained by these types of logs. The numerical model in which both an enhanced thermal conductivity contrast due to heterogeneity, and salt body characterized by a broad mushroom-like head above a thin stalk, best satisfies the observational data. Coupling in fluid flow appears to be an important heat-transfer mechanism away from the dome only (due to the large percentage of relatively impermeable shale present around the salt). It also appears possible that the Bayou Bleu dome might have an overhanging shape which suggests the presence of unexploited targets below a possible overhang.