On 1 March 1993, W.G. Leach published a three-part OGJ article confirming that “The bulk of all oil and gas reserves in the South Louisiana Tertiary sands is concentrated near the top of abnormal pressure.” But on 3 Nov 1997, Guzman et al. demonstrated in an OGJ article the usefulness of seismic velocity data for explorers by publishing numerous named examples of velocity slowdowns above some famous oil and gas fields in the GOM and onshore South Texas. This apparent contradiction spooked us. The puzzle has now been resolved using Hydrocarbon Migration Tomography (HCM) scans.

Today, the case studies presented will illuminate, for probably the first time, the HC migration pathways from their putative sources into and through famous oil and gas fields and costly dusters on the shelf, in deep water, and abroad. Explorers may experience a “come-to-Jesus” moment.