Doddington Chalk.
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Thanks for looking... Here is the Earth Science bit...
Chalk
Chalk is a soft white, finely grained material. It is a pure limestone and are built up in layers gradually over millions of years.
Chalk is formed by the remains of coccoliths, a single cellular phytoplankton, or an algae. They lived in the Cretaceous period, which is a period of time approximately 100 million years ago, (also a time period that dinosaurs roamed the Earth).
The algae lived floating in the upper levels of the oceans and when the algae died, they sank to the bottom of the sea. They combined with remains of all the other creatures and eventually formed Chalk.
Over millions of year the seabed has now become exposed in many areas across Western Europe, the most famous being The White Cliffs of Dover. This outcrop you can see here in Doddington is from the same formation as Dover. The map below shows the regions of Kent that Chalk is located.
Chalk that we see, for example at the White cliffs of Dover is unusual in the depth of the layer of chalk. this unusually large depth indicates that the conditions 100 million years ago, and for possibly many millions of years previous was very stable and the algae was flourishing.
Chalk in my opinion looks pretty cool under microscope. If the image shows these coccolith organisms, it is an unimaginably huge volume of cells which created all the chalk that can be seen throughout Kent.
The Chalk seen here is part of the "Chalk Group" this is a European unit of chalk deposited during the late Cretaceous Period.
It forms the White Cliffs of Dover, as well as the Cap Blanc Nez, on the other side of the English Channel. Additionally, the Champagne region of France is mostly underlain by chalk deposits, which contain artificial caves used for wine storage.
Some of the highest chalk cliffs in the world occur at Jasmund National Park in Germany and at Mons Klint in Denmark – both once formed a single island.
For comparison, White cliffs are about 110m or 360 feet in height, Mons Klint is up to 140m (460ft) high and Jasmund cliffs (pictured below) are up to 160m (525ft) in height.
Chalk has many uses, but not all chalk is the same substance. For example, the chalk here is made of calcium carbonate, CaCO3, which is Calcium, Carbon, and Oxygen. French chalk used to repair bicycle punctures is a natural magnesium silicate, and the chalk board chalk is actually gypsum, or calcium sulphate.
Chalk is more resistant to weathering than clays and soils that usually top it. Being more resistant to weathering, chalk outcrops and cliffs appear as the other materials (soils) surrounding it are washed away. Chalk, a porous rock, meaning there are spaces within the material, can actually hold a large volume of water within it. Water penetrates the chalk and is gradually released through drier seasons. You can often feel this to touch.
I hope that is some interesting nuggets of information about chalk for you to digest...
OK now for some questions...
1. At the posted coords, please look at the chalk and describe the formation, please describe the colour and any features you notice within the chalk face. (Is the chalk smooth, rough, fine, coarse).
2. Is the formation what you expected? If not what did you expect it to look like?
3. Please measure the features within the chalk? How big are they and what shapes are they?
4. Take an elevation reading. Are you higher than any of the top of the White Cliffs of Dover, or Mons Klint, or Jasmund?
5. How do you think this outcrop of chalk came to be visible?
Please submit answers to me and log your find.
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