North Yorkshire Geodiversity Partnership

Ingleton Quarry, Precambrian
Malham Cove Carboniferous
West Burton Falls Carboniferous
Cleave Dyke Quarry, Jurassic


Geological Sites

Geological Sites

Rocks for us

Rocks For Us

Precambrian to Silurian – Ancient Roots

Precambrian, Ordovician and Silurian Periods (over 545 to 417 million years ago) – Ancient Roots

Over 500 million years old, the ancient roots of the Dales, the greywacke sandstones and slates of the Precambrian Ingleton Group, are seen in the quarries and waterfalls of the Rivers Twiss and Doe in Chapel le Dale, upstream from Ingleton, and further east near Horton in Ribblesdale.

diagram-01diagram-02The succeeding strata are missing, as this basement sequence was folded and eroded before it was overlain by the late Ordovician and Silurian rocks of the Windermere Supergroup. These grey slates and greywacke sandstones began life as muddy and sandy submarine flows (turbidity currents) (1 and 2) in a deep ocean basin, and were deposited over a time interval that spanned 446-417 million years ago.


Craven-Inliers0302Figure: Pre-Carboniferous rocks of the Craven Inliers (Source: Aitkenhead, 2002) © BGS (NERC)

Thornton-ForcePhoto: Thornton Force, Ingleton – Precambrian Ingleton Group rocks, unconformably overlain by the limestones of the Carboniferous, Great Scar Limestone Group