Please beware of loose rocks though for the purposes of this Earthcache it is not necessary to climb on the rock face. The cache is wheelchair accessible but please note the approach is on an incline.
Sedimentary rocks, such as the Kirkburton sandstone you see here, are normally deposited as horizonal layers. Here though, you can see layers within that are at an angle to the main plane and this is an example of cross bedding. Look at the rock face, you can see many lines not all in the same direction.
Cross-bedding is formed by sediments that have been carried over the edge and down the slope, carried by water or blown in the wind. The stone here was formed 310 million years ago in the Carboniferous period by one or more large rivers coming from the mountains to the North East. Sand that has been carried by currents (in river, coastal and marine environments) develops a distinctive curved shape.
There are 2 main types of CROSS BEDS based on their shape along a cross section perpendicular to the flow direction.
TABULAR (or Planar) With bounding surfaces that are flat/level.
and
TROUGH With bounding surfaces that are curved.
Cross beds always dip down in the direction towards which the water or air was flowing. If the flow is shallow, beds do not form. If the water is quite deep and speed is low, or the grains are large trough cross beds will form but if the speed increases or the grains are smaller, tabular cross beds will form.
Geologists can tell a lot from this about what an area was like millions of years ago. How the sediment was transported, where it came from, the age between the different layers, and what the environment was like at the time. The style and the size of the beds can be used to estimate the speed of the current and the direction they are dipping determines its approximate direction.
There is a board at GZ with further information and, although not a part of this Earthcache, there is an information board at the suggested Trailhead Waypoint. This tells much of the history of the area and how, in 1855, the fall of Sevastopol was celebrated here!
IN ORDER TO CLAIM THIS EARTHCACHE please message or email via our Geocaching Profile the answers to the following questions
1. Look at the cliff face. What type of cross bedding can you see here?
2. Where in the cliff face is the cross bedding more evident (top, middle or bottom)?
3. In which direction was the current flowing (right to left or left to right) and explain the reason for your answer.
4. At approximately what angle (in degrees) from the horizontal does the cross bedding lie?
5. Upload a photo of yourself (or a personal item that will prove your visit) with your log. Please ensure the photo does not give away any of the answers!
PLEASE NOTE that logs not fulfilling these requirements will be deleted.
Congratulations to DoodleMaster and SnowHunter5 for FTF