Abstract

High-resolution remote sensing and potential methods data sets bridge the resolution gap between exploration-scale "prospecting" and the regional mapping or "screening" to which they have traditionally been applied. Seismic data can be effectively augmented or at times replaced with such data to economically map prospect-scale features and thereby evaluate frontier or deep water areas with sparse seismic coverage. Some of the most useful results come from derivatives of more familiar formats. For example, horizontal and vertical derivatives of topographic, magnetic, and gravity data typically sharpen anomalies, helping emphasize structural aspects of the features they image.

NASA-acquired SRTM (Shuttle Radar Topographic Mission) data afford mapping of large onshore areas. These data are publicly available with a lateral resolution of 90 m, but require an investment of time to usefully format them and generate derivatives. Combined with predicted bathymetry and high resolution satellite-based gravity and derivatives, a powerful cadre of geospatial images can be generated.

New features have been detected, and the locations of known but poorly located features are refined. Seamounts provide excellent illustrations of this. Although not themselves exploration targets, they are easily recognized and have a 6-8 km diameter comparable to typical exploration targets. They have a decided 'donut' shape on gravity and topographic horizontal derivatives besides their characteristic conical form in topographic data. Buried features can similarly be detected. Additions have been made to the seamount inventory in the South China Sea (SCS), and previously named seamounts have been accurately located in relation to their published coordinates.

Of particular interest to petroleum exploration, are imaged fault-block related ridges that, by analogy with reservoir reef-bearing ridges, can be considered prospects. Fracture patterns, fault and fold trains, and other lineations show clearly with enough detail to link to other known and interpreted features for confident geological mapping. This poster includes illustrations of each of these examples in Eastern Indonesia and the SCS.