Formation dynamics of subsurface hydrocarbon intrusions following the Deepwater Horizon blowout

Scott A. Socolofsky; E. Eric Adams; Christopher R. Sherwood

doi:10.1029/2011gl047174

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Formation dynamics of subsurface hydrocarbon intrusions following the Deepwater Horizon blowout

Scott A. Socolofsky·E. Eric Adams·Christopher R. Sherwood

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Abstract

Hydrocarbons released following the Deepwater Horizon (DH) blowout were found in deep, subsurface horizontal intrusions, yet there has been little discussion about how these intrusions formed. We have combined measured (or estimated) observations from the DH release with empirical relationships developed from previous lab experiments to identify the mechanisms responsible for intrusion formation and to characterize the DH plume. Results indicate that the intrusions originate from a stratification‐dominated multiphase plume characterized by multiple subsurface intrusions containing dissolved gas and oil along with small droplets of liquid oil. Unlike earlier lab measurements, where the potential density in ambient water decreased linearly with elevation, at the DH site it varied quadratically. We have modified our method for estimating intrusion elevation under these conditions and the resulting estimates agree with observations that the majority of the hydrocarbons were found between 800 and 1200 m.

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Geophysical Research Letters Article

Source-reported bounding extent: 25.799891182088334° to 29.391747742992806° latitude; -92.977294921875° to -87.462158203125° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Scott A. Socolofsky, E. Eric Adams, Christopher R. Sherwood. 2011-05-12. Formation dynamics of subsurface hydrocarbon intrusions following the Deepwater Horizon blowout. https://doi.org/10.1029/2011gl047174

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