Quantitative Structural Mapping: Visualization of Near-Surface Geologic Structure Using Sateffite Imagery
AMOS, JOHN
F.,
JOHN
R. EVERETT, and RONALD J. STASKOWSKI
One key technical component of successful exploration for geologic resources
(hydrocarbons, water and minerals) is understanding the subsurface,
three-dimensional arrangement of rock layers. This subsurface structure
determines how and where geologic resources form, move and accumulate. We've
developed an advanced structural analysis technique that relies on time-tested
principles every geologist learns in school, but exploits satellite image data
to provide the topographic and geologic information needed for subsurface
modeling of geologic structures. We call
this technique Quantitative Structure
Mapping (QSM).
The QSM approach is straightforward, and has already been successfully demonstrated over the past two years in projects for major oil exploration companies. Here's how it works: we derive the topography using optical image stereopairs, radar image stereopairs, or radar interferometry; identify key surface geologic features (stratigraphic contacts and fault traces) on the optical images; build a Structure Control Point (SCP) file that contains faults and the location, elevation and stratigraphic position for thousands of rock outcrops distributed across the images; and build a solid model of the structural surface using the SCPs.
We can graphically display the model in a variety of ways to help the exploration geologist identify and visualize subtle structural deflections, and communicate them to co-workers, field parties, and managers: as the conventional structure contour map used by all geologists, as a three-dimensional "fishnet" perspective diagram, even as a color-shaded, artificially illuminated solid surface seen from many different viewpoints.