Imaging in the Colombian Foothills

Nick Burke, Steve Knapp

Exploring for hydrocarbons in mountainous thrust-belt areas is one of the great challenges for seismic imaging. The Llanos foothills of Colombia combine both difficult mountainous terrain and complex geology. The application of appropriate technology in both the acquisition and processing of the data has led to a risk reduction in the exploration phase of the trend and greater confidence in the reserve base in the exploitation phase.

Early seismic data (pre 1991) show large anticlinal structures, but do not permit accurate subsurface prediction. Both acquisition and imaging techniques were not adequate to address the problems. A significant effort over the past three years using state of the art acquisition and processing imaging technology has resulted in substantial improvements in the quality of the seismic data. As a result, deep shotholes are being drilled routinely in the mountains and a range of imaging techniques are implemented.

Standard processing techniques are used for stacking the data; the imaging strategy includes both post-stack and pre-stack time and depth migrations. However, integration between acquisition, processing and interpretation staff, as well as between BP and it's contractors, are key to improving the data quality.

AAPG Search and Discovery Article #91020©1995 AAPG Annual Convention, Houston, Texas, May 5-8, 1995