An earth cache with parking close by.
To claim the cache you will need to visit the GSP given, look for clues to answer the questions and email or message your answers to me.
You are welcome to log your find and send your answers at the same time
From the car parking (which you may have to pay for) head down to the beach either by the steps or the ramp. Here you will find a golden sandy beach with many groynes, (those wooden things that stretch out into the sea)
On the beach and especially around the groynes you will find many pebbles, you are looking for ones which are white on the outside and darker in the middle, many will be broken open so they are easy to identify.
When you have found some examples please read below to find out what you are looking at
Cretaceous white limestone, also known as chalk, such as is found close to this location, was formed between about 140 and 60 million years ago. These particular outcrops were formed towards the end of that period. It is made up of millions of skeletons and shells of long dead creatures deposited in of the floors of warm shallow seas.
This rock is also scattered with quite easily found fossils but you have to know what to look for. You may find evidence of small creatures in the rocks but that's not the focus of this EarthCache
If you were looking at a rock face, to the east, of this beach you might find embedded in the rock other, much larger objects which are the focus of the questions below, here is a hint as to what you are looking for.
Embedded in the white rock would be strange fist sized (or smaller) objects which are a different type of rock. The exact mode of formation of these globules is not yet clear but it is thought that it occurs as a result of chemical changes in compressed sedimentary rock formations, during the process of diagenesis. One idea is that a gelatinous material fills cavities in the sediment, such as holes bored by sea creatures and that this becomes silicified. This hypothesis certainly explains the complex shapes of the nodules that are found. Certain types of this rock, such as that from the south coast of England, contain trapped fossilised marine flora. The actual name of this type of rock should be familiar to you but if not, it is on the notice board.
This rock is a hard, sedimentary cryptocrystalline form of the mineral quartz, categorized as a variety of chert. It occurs chiefly as nodules and masses in sedimentary rocks, such as chalks and limestones. Inside the nodule, it is usually dark grey, black, green, white or brown in colour, and often has a glassy or waxy appearance. A thin layer on the outside of the nodules is usually different in colour, typically white and rough in texture.
If you were to break these nodules open by cracking two together they will shatter to give sharp edges, however the action of the waves has weathered and eroded these sharp edges and all you can now see is rounded stones with traces of the original softer limestone clinging to the nodules
So now you know what you are looking for and you should have enough information to answer the questions below.
Questions
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Please find a few examples of the chert, sometimes called flint and a few examples of other stones from the beach. Please compare them for hardness and durability,( you can do this by tapping or rubbing them together) tell me their similarities (by describing the different types of stones) and how they are different and explain the reasoning for your answers.
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Please given me an idea of the percentage of flint/chert in the piles of stone.
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Please tell me the number of the wooden groyne the GPS reference is closest to.
If you feel willing and able, please include a photo of your visit, but be careful not to give away answers the questions above.
Thanks for visiting the cache and I hope you thought it was worth a stop.
treboR