There is growing evidence that the upward migration of light hydrocarbons escaping from a reservoir and the accompanying geochemical processes cause changes in the physical properties of the overlying near-surface rocks, changes that are geophysically detectable. Surveys carried out in several areas, compiling data of different types, geological, surface geochemical, surface geophysical and high resolution airborne magnetics, are presented to illustrate the resulting multidiscipline correlation of information and allow reflection on its suggested significance and petroleum exploration potential.

AAPG Search and Discovery Article #90928©1999 AAPG Annual Convention, San Antonio, Texas