Growing up in Umdloti, I have had many fond memories of this particular spot.
So here is my first earth cache!
The first sedimentary sequence deposited on the new basement was the Cambrian to Ordovician Natal Group (490 million years ago).
The rocks overlying the Natal Group is a thick unit of tillite that was deposited in a glacial environment by retreating ice sheets about 300 million years ago.
At this time South Africa was part of the supercontinent Gondwana, which was situated near the south pole and covered with ice. Rocks imbedded in the slowly moving ice sheets scoured and polished the underlying older rocks giving rise to glacial pavements. Striation directions indicate that ice flow was from north to south - valuable information when it comes to reconstructing Gondwana. The Dwyka Group forms the lowermost and oldest deposit in the Karoo Supergroup basin. This basin extended across much of southern Gondwana and records 120 million years of geological history.
Tillite is mostly a very fine-grained, blue-grey rock comprised of clay matrix with inclusions (or clasts) of many other fragments picked up by glaciers during their travels.The tillite in KZN often weathers to a characteristic yellowish colour. In the Durban area, cliffs near the mouth of the Umgeni River, and quarries in the Westville area offer the best exposures of tillite.
More samples can be found to the left of GZ and further down the beach towards Durban.
As is already evident, the rock series of KwaZulu-Natal – with the notable exception of the coastal region’s Cretaceous and Cenozoic marine sediments – belong to the ancestral Gondwanaland and are thus older than the province itself. Because the Basement rocks were formed deep within the earth’s crust, their component minerals are often unstable at the surface and prone to rapid decay into clay, sand and grit.
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At this location you will need to answer/describe and hopefully snap a memory of this amazing spot that has kept me and my family coming back for the last 29+ years.
This Cache is best done at low tide. But High tide is just as spectacular! So I suppose the change of tides is the best time!
With all of the ocean, please be ever watch full of the sea with youngsters! And be careful when exploring, the rocks are sharp and lots of drop offs!
At GZ you will meet an age old formation. Carved but nature, and standing strong against the most aggressive, unpredictable and purely awesome force of nature.. The Ocean!
The only way to enjoy this is to get to GZ and explore, sadly you will however notice one item which you will need to answer in the questions below.
To claim this Earth Cache please email me the following answers. Do not post them on the cache page.
1: What rock type do you think this structure is made of?
2: In your own words what do you think cause this form of erosion?
3: At the following reference point (S 29° 39.981 E 031° 07.338) describe the object you are brought too. How does it differ to everything else around you and what do you think caused this / or is it made of another type of rock or mineral?
4: At GZ, the published co ords. It is a bit of a climb, be careful, but once there take a moment and look around. Enjoy! Pretty much in the middle of this pillar, is a clump of something? (not grass!) Describe it?
5: Describe one NEGATIVE item that you notice all around GZ! In your own words describe what the main cause of this is.
Now for the questions that CAN be added to the online log..
6: Describe the view, the day and the ocean.
7: This is not required but nice to have. You need not take a pic of yourself if you do not desire, but pics of the views (except question 3 and 4) would be nice.
And one last feel good request;
If you feel up too it, please can you look at Question 5 again and maybe do one or two things to reduce it. It may not be much but it will be a start!