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The primary objective of the high-resolution survey was to offer a detailed subsurface image of the complex P2 fault zone, hosting the world's largest high-grade uranium deposits. Raw seismic data have low signal-to-noise ratio; nevertheless the implemented processing procedure considerably improved its quality. Interpretation of the two lines integrates all available background information such as regional geology; structural, stratigraphic, and diagenetic features associated with the borehole information including stratigraphic and petrophysical properties; and seismic analogies for the basement from other high-grade metamorphic terranes. The resulting interpretations generally agree with previous geological knowledge, but add new exploration insights, such as: 1) the complex 3-D geometry of the P2 fault zone, 2) the existence of additional dekameter-scale, fault-controlled structures associated with the P2 zone, 3) syntectonic deposition of the upper parts of the Manitou Falls Formation in this area; and 4) the internal architecture of the metamorphic basement.

Seismic-reflection data and a vertical seismic profile were acquired in the vicinity of the McArthur River mining camp. These data are interpreted with the aid of in situ geophysical and geological logs and rock-property measurements, which indicate that reflectivity within the basin-fill strata is controlled largely by porosity variations (Phi = 0 - 11%) that are attributed primarily to zones of silicification (postdepositional hydrothermal horizons), but also to grain-size lithological variations. The reflection data clearly image the unconformity zone and associated fault offsets including the P2 mineralized fault zone. A prominent shallow- to moderately dipping zone of reflections that extends downward from the surface location of the P2 fault is interpreted as a major crustal shear zone that partially controlled the locus of high-grade uranium ore deposition. The seismic techniques have demonstrated their utility in defining some of the key geological variations that are relevant to identification of prospective ores zones.