AN INSIGHT INTO THE WALTON BASIN, OFFSHORE JAMAICA - A FALCON® PERSPECTIVE

Abstract

A high-resolution, high-definition FALCON® airborne gravity gradiometry and magnetic survey - the largest offshore FALCON® survey to date - was flown during mid-2006 over parts of the Walton Basin offshore Jamaica. This data was acquired in conjunction with a marine 2-D reflection seismic survey. The Walton Basin is a relatively under-explored Early-Tertiary rift basin located near the western margin of the present-day Nicaraguan Rise and forming part of the Chortis Block of the greater Caribbean Plate. Results from the seismic survey were augmented with historic offshore seismic data, and a series of key structural events were successfully mapped across much of the Walton Basin. A number of leads and prospects ranging from Late-Cretaceous to Mid-Miocene in structural and stratigraphic traps have been identified with several prospects hosting multiple targets. Preliminary evaluation of a number of these prospects indicates the potential of multi-billion barrel oil accumulations. Preliminary interpretations of the FALCON® datasets have allowed confident mapping and correlation of the shallow intra-basinal sediments in addition to the mapping of deeper basement structures and geometries where the seismic resolution is limited. An integrated approach of employing conventional interpretation methodologies, 2D-forward modelling, 3D-Euler technique and constrained 3-D inversions have shown clear links between the seismic data and the high-resolution potential field data and enabled a more accurate understanding the architecture and stratigraphy of the Walton Basin for hydrocarbon prospectivity. The FALCON® data has enabled quantitative assessment of risk with significantly higher confidence than would be afforded by seismic data alone.