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Holker Estuary Cliffs EarthCache

Hidden : 7/23/2009
Difficulty:
2.5 out of 5
Terrain:
1.5 out of 5

Size: Size:   other (other)

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Geocache Description:

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This earthcache is located in the Holker Estuary. The area is known as Old Park Woods after the local caravan park. The earthcache here is for the limestone cliffs.

If you go to the GZ, you should be able to see the Limestone cliffs. This limestone is Carboniferous limestone. This means it was formed in a tropical sea which covered the UK 359 million years ago. This would have occured in the Dinantian sub period of the Carboniferous era.

Carboniferous limestone is a sedimentary rock made of calcium carbonate. It is generally light-grey in colour, and is hard. It was formed in warm, shallow tropical seas teeming with life. The rock is made up of the shells and hard parts of millions of sea creatures, some up to 30 cm in length, encased in carbonate mud. Fossil corals, brachiopods and crinoids are very much in evidence as components of Carboniferous limestone; indeed the rock is full of fossils.

Carboniferous limestone has horizontal layers (beds) with bedding planes, and vertical joints. These joints are weaknesses in the rock, which are exploited by agents of both denudation and weathering. They also lead to the most important characteristic of Carboniferous limestone - its permeability. Water seeps through the joints in the limestone. This creates a landscape that lacks surface drainage but which has all manner of characteristic surface and subsurface features. The Carboniferous Limestone has been folded and faulted by massive Earth movements which can be seen by the fact that the rocks are now above sea-level and no longer horizontal.


In order to claim this Earthcache as find please carry out the following requests.

1) Please take a picture of the cliffs with you or your GPS in the photo

2) Please take a picture of the bedding planes.

3) Estimate the height of the cliffs.

4) Take a picture of some aspect of the wildlife. This can be flowers, birds, fungi - anything you want.

Please include all photographs in the logs and email me the answers to the questions.

Additional Hints (No hints available.)