It is known that economic production of shale gas is currently possible only where shale is naturally fractured. The exploration problem is therefore to locate zones of fracture. In principle, extenstive zones of natural fracture in a thick shale can be identified by the measurement of seismic velocity from the surface. The technique of reflection velocity analysis uses differential reflection time of reflections observed at the surface (with various source-geophone distances) to infer the extent of the gas saturated fracture zones. This technique has been applied along an available seismic line in Southeastern Ohio. A continuous velocity analysis of the shale interval along this line was prepared, and areas of depressed velocity have been identified. These results, and the results of drilling in the first area of low velocity will be discussed.

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