The producing fields of eastern Ohio lie along the west side of the Appalachian syncline where the normal southeast dip is broken by the minor structures which resulted from the Appalachian folding.

The most important structural feature is the broad northern development of the Burning Springs-Volcano anticline which is paralleled on the west by the deep Parkersburg syncline. This general uplift has a width ranging from 25 to 30 miles, and extends about 80 miles northeastward into Ohio from West Virginia.

Twelve shallow sands occur in the Pennsylvanian and Mississippian systems, and two deeper sands have been extensively developed.

The most consistent shallow sand accumulation has been along the general anticlinal structure, and is controlled by local structure, generally lacking any definite trend.

Geological work on the Pennsylvanian and Mississippian sands has been generally successful, but the interpolation of the structure of the deeper sands which lie in the Devonian and Silurian is made more difficult by the rapid eastward expansion of these two systems.

The Cambridge gas sand, which occurs near the base of the Devonian, has been extensively drilled in eastern Guernsey County, where the sharp reversal caused by the Parkersburg syncline is sufficient to overcome the westward convergence of the upper Devonian shales. If this sand is present along the entire length of this uplift, new fields may be discovered in the direction of Parkersburg. East of Guernsey County the dip is too sharp and the convergence too great to be overcome by such reversals as exist.

The Clinton sandstone, near the base of the Silurian, is the deepest producing horizon in eastern Ohio. From a heavy quartzose bed in the extreme eastern part of the state it pinches westward into isolated lenses, in the more porous of which the production occurs. This sand is absolutely devoid of water, which feature, together with the lenticular nature of the reservoirs, renders extensive geological work impractical.