Ederney Quarry ASSI

Ederney Quarry is a special place because of its Earth Science interest. The area provides access to important rock exposures.

The rocks are sedimentary and a mix of limestones, sandstones and mudstones. They were originally deposited as soft sediment during the Carboniferous period of Earth history, around 350 million years ago. At that time, what was to become Northern Ireland was covered by shallow seas.

The rock sequence at Ederney Quarry records a move from deeper to more shallow water. Fossils are found throughout the range of rock exposures that help date the different layers and show us what kind of ancient life lived in the seas.

Ederney Quarry is also a ‘type locality’ for a particular layer of limestone, known as the ‘Ederney’ Limestone. This type of sites is important for geologists working on rocks of a similar age in other parts of the country.

Furthermore, the south face of the site records an ancient earthquake – the Aghaleague Fault. The relatively smooth rock is the fault plane i.e. where rocks moved past each other. Some folds can been seen in the rocks caused by this fault.