Ingleborough

Today's the day .......................... for a bit of geology

Had a little sortie across the border into Yorkshire today. It was bitterly cold with the odd flake of snow falling - and the tops of the Yorkshire Dales were quite white. This is Ingleborough, which at 2,372 ft (723 m) is the second highest peak in the Dales after Whernside.

It has such a distictive shape which owes everything to the unusual geology of the rocks that it is made from. At the base are ancient Silurian and Ordovician rocks over which lies a thick belt of Carboniferous Limestone - the 'Great Scar Limestone'. It is the great permeability of this limestone that has been responsible for engulfing all the streams flowing down from the mountain - which in turn have resulted in the incredible series of caves and caverns that are to be found on Ingleborough.

Above lies a horizontally-layered series of sedimentary rocks, predominantly shale and sandstone but with some layers of harder limestone sandwiched between, protecting the softer rocks and giving the 'tiered' effect. Then to cap it all (literally), the whole mountain is protected from erosion by 100 feet (30 m) of a very hard rock known as Millstone Grit which gives it its flat summit.

On the top of Ingleborough, the remains of an old walled enclosure have been discovered inside which foundations of Iron Age huts have been found. It has been a familiar shape in the landscape for a very long time ..........................