The Rocks of Penny's Bend

Principal Rock Types:


Triassic Sedimentary Rocks

Diabase outcrop
Triassic Sediments
Triassic Sedimentary Rocks

Diabase - Diabase is a intrusive igneous rock that is approximately 200 million years old (Jurassic aged). The diabase intruded into the Triassic aged sediments as dikes and sills. Diabase is composed of minerals that contain abundant calcium, iron and magnesium in comparison to the Triassic sediments.  Because of the abundance of calcium, iron and magnesium, unique plant communities sometime develop on top of areas underlain by diabase. Diabase is more resistant than the surrounding Triassic sandstones and siltstones and often forms resistant ridges in the Triassic basin.  Penny’s Bend is mainly underlain by diabase. 

Triassic Sedimentary Rocks - Triassic sedimentary rocks consist of approximately 220 million year old (Triassic aged) sandstones, siltstones and mudstones that were deposited with in the Durham Triassic Basin. Rocks associated with the Durham Triassic basin are exposed along the Eno River east of Roxboro Road.

Please remember that rock and mineral collecting is STRICTLY PROHIBITTED on protected land!



Want to learn more about the geology of the Eno River area?

You may be interested in A Geologic Adventure Along the Eno River - A richly illustrated publication from the North Carolina Geological Survey.