The gently dipping Olive Hill Clay Bed of Crider (1913) crops out in belt about 15 miles \vidc and 60 miles long from the Ohio River near Portsmouth, Ohio, south-southwesterly to Frenchburg, Ky. (see inset map).
The purpose of the structure-contour map presented here is to aid exploration by showing the elevations at which the Olive Hill Clay Bed occurs. The strudure contours indicate the depths that mu;,t be reached in prospecting for the clay. The approximate depth of the clay at any one point is the difference between elevations of the structure and topographic contours. The clay has been thoroughly prospected along its out.crop belt and in most areas \Vhe re it lies under overburden less than 200 feet thick. The depth of the clay bed increase,; eastward from the outcrop belt, and large potential resources are likely to occur at depths greater than 200 feet.