Gas in commercial quantities was first discovered in 1964 in Harlem Township, Delaware County, by Federal Oil and Gas Company in their 1 Fronk well. This well had an initial production of 4,435 MCFGD after treatment, from the Black River Limestone (Ordovician). Following this discovery, several unsuccessful attempts were made through the 1970s to locate additional reserves in this area.

After an extensive geophysical investigation of the area, Industrial Natural Gas Corporation drilled the 1 Jackson well in 1982. This well had an initial production rate of 225 MCFGD and proved there were additional reserves in the field. Since then, numerous wells have been drilled defining this field, and more than 300 mmcf of gas has been produced.

The geology of the field is more complex than that associated with most oil and gas deposits within the state. The reservoir is located along a northwest-trending fault and fracture system. This fracture zone cuts a northeast-trending anticlinal nose. The reservoir rock is dolomitized Trenton and Black River Limestone. Trapping is accomplished by porous dolomite sections being surrounded by relatively impermeable limestone and dolomite.

This field provides a modern model to which future exploration for hydrocarbons in the Ordovician carbonates of Ohio may be keyed.

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