Advance warning of loop current from single-site seasonde on genesis oil platform in the Gulf of Mexico

Abstract

A single SeaSonde HF radar operates on Chevron's Genesis deep-water floating platform in the Gulf of Mexico. The radar's purpose is to provide advance warning of strong loops or eddies that approach the rig. A single radar like this, however, only produces a map of the surface current component toward or away from the radar, called a radial map. A pair of radars with overlapping coverage is required for a 2D total vector map. Despite this limitation, and overcoming the strong antenna pattern distortions caused by the all-steel rig, useful information was obtained to a distance of 90 km. To verify the accuracy and utility, comparisons were done with an ADCP 72 km away. Low-pass filtering was used to remove short-term inertial oscillations, revealing close agreement with the 40-m deep ADCP measurement of the persistent geostrophic loops. Both saw the strong loop features.