Pumpernickel Valley geothermal project area is located in the Basin and Range province, within the structurally complex Winnemucca fold and thrust belt of north-central Nevada. The project area is cut by a series of normal faults, two of which, the Pumpernickel Valley fault and Edna Mountain fault, are range-bounding faults, which also display some characteristics typical of strike-slip fault systems.

Within the project area, abundant hot springs, seepages, and wet ground/vegetation anomalies are present next to the Pumpernickel Valley fault. The widespread hydration and alteration around the fault indicate that it focuses the fluid up-flow, whereas the nearby, down dropped structural blocks may define an immediate reservoir.

A 3D resistivity survey, which included both main faults and all geothermal features, was carried out within the project area. The survey results delineated a broad conductive zone associated with two highly conductive anomalies and numerous, unexposed en echelon structures. Combined with the geological data, the resistivity results are interpreted to indicate the presence of a complex pull-apart basin, formed within the releasing bend of the Pumpernickel Valley - Edna Mountain fault system.

Following the geological and geophysical surveys on the property, Nevada Geothermal Power Company/Inovision Solutions Inc. drilled four temperature gradient boreholes, three of which were located within the large conductive zone. The preliminary geothermal data from this drilling outlined a field with thermal gradients in excess of 100oC/km. Together, a substantial body of evidence exists to suggest that the pull-apart basin hosts an extensive geothermal field.

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