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Site content related to keyword: "Mount Cuba"

Outcrop Bc32-a: The Mt. Cuba Picnic Grove

Rock Outcrop Bc32-a: The Mt. Cuba Picnic Grove

The Mt. Cuba Picnic Grove provides an opportunity to look at the gneisses and amphibolites of the Wissahickon Formation. The large boulders of gneiss lying beside the steps are peppered with dark-red garnets and elongated nodules of dull-white sillimanite. These sillimanite nodules (1/4" to 3/4" long) are abundant in the gneisses at Mt. Cuba and are an interesting feature of these highly metamorphosed sedimentary rocks. Alternating layers of gneisses and amphibolites crop out on the east side of the track. The gneisses show some typical upright folds and fractures. Contacts between the layers trend northeast, parallel to the regional trend of the Appalachians.

Outcrop Bc32-b: The Mt. Cuba Railroad Cut

Rock Outcrop Bc32-b: The Mt. Cuba Railroad Cut

The Mt. Cuba railroad cut is narrow and deep, and much of the rock is covered with dirt and soot from the train. The rocks are interlayered gneisses and amphibolites, with gneisses predominating in the south end of the cut and amphibolites in the north end. Folding is well developed, but the angle of the sunlight as it shines on the walls of the cut will determine which of the folds will be the easiest to see. A 4" amphibolite layer outlines the fold in this part of the outcrop. Wonderful examples of the effects of rock type on folding styles can be seen in the cut and in many of the rocks piled north of the cut.

What are GeoAdventures?

The Wilmington Western Railroad follows the Red Clay Valley through the Delaware Piedmont cutting through many of the Piedmont rock units.

GeoAdventures are designed to allow the reader to learn about a particular geologic point of interest in Delaware’s Piedmont province and then take a short field trip to that area. Want to know more about the Wilmington blue rock or Brandywine blue granite? Take the Wilmington Blue Rock GeoAdventure and go see just what the blue rock looks like.