Image Interpretation Techniques: Obscured and Buried Structures

As illustrated in the previous chapter, satellite imagery can provide an excellent tool for detection and analysis of geological structures that are well exposed at the surface and manifest clear expressions of inclined bedrock strata and fault-line traces. However, a large percentage of the world’s onshore hydrocarbon reserves is either obscured by thick cover of vegetation and soil in areas of low topographic relief or is completely buried under younger and relatively undeformed rock units. In these regions, the recognition of subtle topographic expression of structures can no longer be accomplished by measurement of exposed outcrops. Rather, the interpreter must rely on the recognition of local drainage, moisture and fracture patterns which indirectly reveal the presence of subsurface structures in the area.