An easy EarthCache designed to be easy for beginners.
Along the beach at the town of Stansbury are prominent cliffs, an interesting geological feature that hold fossils and other evidence of life from millions of years ago.
Near the Stansbury Jetty, the cliffs lining the coast are predominantly made up of Port Vincent Limestone, deposited here during the Oligocene to Miocene times, by shallow seas which once occupied the St Vincent Basin, between 20-30 million years ago.
(https://www.futurelearn.com/info/courses/taking-on-the-climate-crisis/0/steps/261255)
Amongst the Port Vincent Limestone is evidence of many fossils:
- Sea-urchins (Echinoderms)
- Clams and oysters (Bivalves)
- Moss animals (Bryozoa, Polyzoa or Ectoprocta)
The cliffs also hold evidence of former caves and sinkholes. These areas stand out due to the fact they are now filled with mottled red and yellow clays.
After the seas had retreated, the limestone left behind was then exposed to erosion and weathering, which formed the caves and sinkholes amongst the rocks.
Following the seas retreating from the St Vincent Basin, natural processes over thousands of years caused the caves to be filled with the clays, the way you see them today.
The former caves and sinkholes are also thought to house the remains of fauna.
Geographically speaking, these caves formed at the same time as the cave systems at Naracoorte and on the Nullarbor, which are also home to many remains of fauna and megafauna. However, as of 2022, no evidence has yet been found of remains residing at Stansbury.
Logging Requirements:
Look at the cliff face at the given coordinates and answer the following questions:
- Can you see evidence of the former caves here? What natural processes filled them with the clay?
- Other than the different colour, what else is unique about these clays when compared to the rest of the cliff face?
- Include a photo of you or your team at the nearby bench, or a personal item or stamp if you prefer.
Please send messages via Geocaching message centre or email, answers posted in the logs will be deleted.
You can log the find immediately, if answers are supplied to CO within 14 days.
Please don't venture too close to the cliff.
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