In the Northern part of the beach you can walk across the remains of an ancient desert. The red rocks were deposited as muds by a desert river in flood about 400 million years ago when Britain lay South of the equator. When the mud dried out it cracked and left the polygon shapes many of us have seen on dried mud today. As the desert sediments were gradually compacted the mud hardened to form sandstone. The brilliant thing is that the 400 million year old cracks still remain. You can also see cream coloured blobs in the sandstone.This is caused by carbonate precipitating as the sun dried out the mud.
In the Southern half of the bay is grey limestone deposited 360 to 330 million years ago by the compaction of the bodies of sea creatures. You can see many fractures and joints caused by the the limestone being dissolved by acidic rain water.
To log this cache please email me the answers to the following questions.
1. What is the geological era known as when a. the sandstone was laid down and b. the limestone.
2. What is the name for the cream coloured nodules in the sandstone.
3. Observe both the sandstone and the limestone closely. Describe the differences in colour, texture and how they have been weathered.
4. How high would you say the limestone cliffs are? What can you observe at the foot of the cliffs. Describe their shape and explain why they are there.
5. Take pictures of yourself or gps with the sandstone behind you and the limestone cliff behind you (optional) OR
6. A fun optional activity for kids old and young. Draw in the sand the cracked patterns that appear on the sandstone. Take an optional photo of your work!
TAKE CARE Be aware of sinking mud and sand on the sandstone end of the beach and take care near the cliffs on the Northern end.Also be mindful of the tide.