The area bounded by the Scioto River to the south and west, and the Whetstone (Olentangy) River on the east lies upon bedrock which is called Monroe and Columbus limestone. Formed over 350 million years ago, this bedrock outcrops in a north-south band through Ohio, shown on the USGS map below at the intersection of Devonian and Silurian strata. This rock played a significant role in the development of the area, because it was quarried from the many quarries in the region, such as is shown in the image above. The stone was utilized in many applications, including stone walls, homes, roads, flux for steel mills, and for the construction of buildings such as the state capitol building in Columbus and Orton Hall on the Ohio State University campus.
Gently sloping alluvial fans formed at the mouth of many ravines in this area. The ravines furnished the silt that over time was laid in the fans. Several such fans on the Scioto flood plain can be seen looking north as you drive along Dublin Road. Several such fans on the Scioto flood plain can be seen looking north as you drive along Dublin Road. The ravines furnished the waste now laid in the fans. Several of these photos are from the USGS book "Geology of the Columbus Quadrangle", by Stauffer, Hubbard and Bownocker, published in 1911 by authority of the Legislature of Ohio.
Gently sloping alluvial fan at the mouth of a ravine near Grandview.
Columbus limestone near Grandview
The upper image is a section of bedrock along a line drawn through Columbus from west to east. The lower image is a closeup of the region near Grandview.
Rock terrace near Marble Cliff, looking nearly north across terrace top to drift bluffs beyond.