Kanmantoo group – 529 million years ago
Dark grey metamorphic rocks of the Kanmantoo group seen on the platform and cliffs below were derived from Gondawana. These were deposited as fine silt in the subsiduary ocean basin during the Cambrian period, after deep burial and metamorphism by heat and pressure they were thrust up, folded, uplifted and eroded. At this time Australia was north of the Equator.
Cape Jervis formation - 280 million years ago
Blanketing ice sheets moved slowly northwards gouging valleys into the Kanmantoo group bedrock. Layers of clay and sand containing boulders were deposited as glacial fill beyond the edges of the melting ice is now exposed in the cliffs. Australia moved south during the Perrenian period, this part of Gondawana was near the South Pole.
Point Ellen formation - 43 million years ago.
About 43 million years ago Australia separated from Antarctica and is still moving northwards
At about 18 million years ago the glacial sediment were under the sea and were covered by a fossil bearing limestone called the Point Ellen Formation. When Australia was about 125 km south of its present position on the earths surface.
To log this Earth cache
1 Compressional forces from the east and west created what event?
2 What colour granite is released from erosion of the Cape Jervois formation?
3 Pick one of the sedimentary rock groups found below and describe ie size, colour shape etc or alternately pick a time period and describe how you think the area would have looked ie climate, flora-fauna etc
Optional any photos of this great scenic location to add to the gallery would be appreciated.
Hope you enjoy visiting Morgan’s Beach go for a walk and explore the beach and rockpools and tell us your adventures in the logs !!!!!