Results show that an initially complex, heterogeneous network of fractures can be reduced to a simplified series of fracture subsets, with two distinct fracture types emerging from the analysis. Bedding-plane partings that strike N84°W and dip 20° to the north are the most numerous. These features exhibit widely varying hydraulic transmissivities that average roughly 5 m²/day and that generally diminish in magnitude and frequency with depth. Structurally derived fractures strike subparallel to the bedding planes at N79°E, but dip steeply (71°) to the south, thereby forming fracture planes orthogonal to the bedding planes. Transmissivities associated with these fractures are, on average, about half those of the bedding-plane partings. The intersections of these two fracture types form linear conduits that retain the common east-west strike direction and have average transmissivity values that are intermediate between those of the individual fractures. The geophysical logging results portray a distinct hydrogeologic structure within this aquifer that is controlled by fracture orientation and type. Since all permeable features strike approximately east-west, local transmissivity is strongly anisotropic. However, this directional dependence is somewhat subdued by the gently dipping bedding-plane partings which permit some north-south fluid movement.

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