SUBSURFACE STORAGE POTENTIAL OF THE ROSE RUN SANDSTONE (LOWER ORDOVICIAN) AND COPPER RIDGE DOLOMITE (UPPER CAMBRIAN), KNOX GROUP, IN NORTHEASTERN KENTUCKY
In the test well, the Rose Run was 32 ft thick, from 3,282 to 3,314 ft below the surface. The lower 13 ft of the formation was collected in whole core. Nine sidewall cores were collected from the upper part of the unit. Porosities from nine samples range from 8.61 to 23.82 percent with a mean porosity of 14.92 percent. Air permeabilities range from 1.5 to 3,144 mD, with a mean of 446.7 mD. The lower part of the Rose Run interfingers with the Copper Ridge Dolomite.
The Copper Ridge is 886 ft thick, from 3,314 to 4200 ft. Most of the Copper Ridge Dolomite is impermeable, but several zones have vuggy porosity with good permeability. Whole core was collected from 3,300 to 3,360.7 ft and 3,750 to 3,810.6 ft. The lower core exhibited vuggy porosity. Two samples from the upper core had porosities of 31.5 and 15.9 percent and permeabilities of 706 and 8.6 mD. Two samples from the lower core had porosities of 2.4 and 23.4 percent, and permeabilities of 2.9 and 29 mD. Sixteen other samples from the cores had porosities from 1.4 to 6.8 percent and permeabilities from 0.0001 to 0.37 mD, with a mean of 0.037 mD. Six samples had permeabilities of less than 0.0004 mD.
Separate step-rate tests were completed in both the Rose Run Sandstone and Copper Ridge Dolomite. Both showed good injectivity without breakdown or significant pressure buildup. Data collected should help future decision-makers evaluate the feasibility of these units, if needed for storage, in northeastern Kentucky and southeastern Ohio, along the Ohio River industrial corridor.