To claim a find on this EarthCache you will need to visit the location given, gather some information, perhaps by reading the listing below or looking around.
Then you need to ether email or message the answers to me, I tend to reply to emails quicker.
Please feel free to send your answers and claim your find at the same time.
Please take only photographs and leave only foot prints.
This is placed on a clear footpath which is called The Dales Way. The climb up from Windermere is gentle and easy to follow but can be wet.
The focus of this EarthCache is the 'flat' rock which seems to emerge out of the turf and is just after the gate you will have passed through, if you are going uphill with Windermere behind you. This rock is a slab of limestone which has been damaged by the passage of ice when glaciers were here during the last ice age.
The rock in particular is about 4m by 2m and has a flatish top. Look on the rock and you will find almost horizontal lines scored into the rock, they are all parallel and vary in depth from less than 1mm to about 3mm deep. These scores marks are plenty-full and though they look like they might have been made by a machine, they are so straight and parallel, they were in fact made from the passage of ice.
Much of the lake district was shaped by the passage of ice. There are many U shaped glacial valleys which were created between 100,000 and 75,000 years ago, this glacial period was popularly known as ‘the ice age’. These ice sheets passed over the area and scraped away the surface of soft land and earth exposing the harder rock below.
As the ice moved over this land it firstly broke off and rearranged the large rocks into the arrangement you see today in areas north of here. Then is would break off parts of the sedimentary rocks and tumble them over in front of the moving glacier smashing them into smaller pieces. As the bottom of a glacier moved it was ‘lubricated’ with a fine alluvium paste, this contained muds, small and larger stones and slushy water. All this acted as a grinding paste for any solid structures it passed over.
This process is called glacial scouring/scaring or glacial abrasion and is responsible for the U shaped glacial valleys that are common in post glacial landscapes, as it scraped away anything soft enough for it to move. Abrasion by glaciers in this area carried a large amount of material with them. Some of these sharp boulders were embedded in the bottom of the glacier and acted as erosive agents for the glacier. These rocks mean that the glacier acted like sandpaper, scouring along the valley floor, the sides and even the tops of small hills, the ice was so thick. The effects of abrasion were that the rock surface of the valley could be polished and the rock surface left behind may have shallow or deep grooves cut in them. These grooves are called striations and though more common on the valley floor can be found anywhere the ice passed over.
Hopefully you now know why this exposed piece of rock is marked in what seem like a machine tooled way, which it turns out was perfectly natural.
Please answer the questions below by either sending an email or message and I invite you to log your find and send your answers at the same time.
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Please describe the surface of the pale flat topped rock surface, concentrate on the marks, including their depth, length and frequency.
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Using a compass rose and some common sense, please indicate the probable direction of the passage of ice, with an explanation of your answer.
Thanks for visiting the area and attempting this cache.
treboR