Kenilworth Cutting Outcrop of Sandstone – Image by WGCG
This image and text below are extracted from the WGCG Interpretation Board – click to see all of it as a PDF in new window
This outcrop tells a story of when Kenilworth lay just north of the Equator in a semi-desert climate with marked wet and dry seasons. The rivers were seasonal. When it rained, the river moved a lot of sand which it laid down as sand bars, but with the main flow in channels on either side. In the dry season, flow almost ceased exposing the sand bar and then muds settled out in the channels
What can we see?
The outcrop (photo above) consists of beds of mudstone (originally mud) and sandstone (originally sand).
- Bed A is a thick bed of sandstone
- Follow the surface above Bed A – this is a bedding plane at the top of the sandstone and is gently arched.
- See how this bedding plane drops away to right and to left
- A bed of mudstone (Bed B) (now weathering and eroding) overlies the sandstone
- In the centre of the section at ‘X’ the bedding planes dip (slope) into the section at 10° away from you into the hill slope.
- In places e.g. at ‘Y’ thin beds dip at steep angles (15°) away from you (i.e. to the south-east); this is an example of ‘cross-bedding’(See PDF)
What does the outcrop tell us?
- The cross-bedding and the shape of the sand grains (See PDF) tell us that the sands were moved by a river flowing away from you. So, imagine you are standing in the bed of this river . . .
- Bed A is an upstanding sand bar with river channels to either side.
- At times flow slowed down (Bed B) and muds were laid down in the channels as drapes over the sand.
Image and text above are extracted from the WGCG Interpretation Board – click to see all of it as a PDF in new window
Partners are shown on the PDF and are gratefully acknowledged.
They include Warwickshire County Council, Sustrans and The Greenway Trust – http://www.thegreenwaytrust.org.uk/geology