Pwlldawnau and Penbwchdy, Pembrokeshire

The little inlet of Pwlldawnau and the headland Penbwchdy, viewed from adjacent to the Pembrokeshire Coastal Path at National grid ref. SM 8808 3692 (a nice place for a sandwich).

The prominent pale rock horizon consists of sandstone and conglomerate at the base of the Ordovician age Ogof Hen Formation. This rests unconformably on the underlying shales of the Cambrian age Lingula Flags. The far headland of Penbwchdy is comprised of a microtonalite sill, an igneous intrusion. If you zoom in on the photo you can see near-vertical columnar cooling joints in the sill.