Channel and Canyon Systems of an Active Margin: Improving and Extending Basin-Level Mapping in the Sabah Basin of Northwest Borneo

Janice M. Christ¹, William G. Dickson², and James W. Granath^3
1 J-SEA Geoscience, The Woodlands, TX
² DIGs, Stafford, TX
³ Granath & Associates, Houston, TX

Prior work by the authors (Christ et al. 2002, Dickson et al. 2003) has explored the correlation between the location of channel and canyon systems (CCS) and the expression of potential field anomalies related to basement and sedimentary structure of passive margins. This paper considers elements of the active margin Baram Delta system offshore Sabah, NW Borneo.

Various publications illustrate the location of two Tertiary fan systems and the related sediment provenance areas. Our work begins by demonstrating a clear correlation between the published "Pink" and Lingan fans versus greatly improved gravity data. Of the various tested gravity attributes, we performed most mapping using a combination of first vertical derivative and dip-azimuth of the isostatic anomaly. While not definitive for depths to individual fans (thus maintaining the need for 3D seismic and drilling data), this illustrates the broad extension of mapping into the deep water limit of clastic sedimentation as well as the extension updip to clastic provenance areas for fan discrimination by reservoir potential. The range of examples includes long transport and short transport variations across a system that extends seaward about 200 km from the present shoreline and roughly 50 - 80 km beyond current publications. This "Whole Package" approach can be used either for quick basin review or as a risking and ranking guide to detailed seismic interpretation.

AAPG Search and Discovery Article #90039©2005 AAPG Calgary, Alberta, June 16-19, 2005