The Use of Lineament Mapping and Electromagnetic Surveying for Detecting Natural Fractures in the Devonian Shale

The natural fractures existing in the Devonian Shale of the Appalachian Basin provide the enhanced permeability necessary to make the shale economically productive. Lineament maps are the predominent means of tracing fractures at the surface, but interpretation errors that are associated with their construction limit their accuracy. This study uses an electromagnetic surveying technique to eliminate these inaccuracies. The first five wells sited with the aid of this method have all intersected fractures. Such surveys appear to be useful for optimizing the location of wellsites.