Carrock Fell’s geology is unique in the Lake District in that it is predominantly composed of Gabbro, a rough igneous rock that also makes up the famous Black Cuillin on the Isle of Skye.
In the southeast along the lake shore they are composed of Triassic Santa Ana Formation and Jurassic dacite and gabbro.
The northern paragneiss zone contains lenses of various lithologies, such as calcareous schists, amphibolite, eclogite, peridotite (mostly thoroughly serpentinized) and gabbro.
His Habilitation was completed soon thereafter under the direction of W. Bruhns on the topic of the Gabbros in the area of Böllstein/Brombachtal.