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Introduction :
Sandstone is a detrital rock that formed about 370 million years ago during the primary era in the Devonian period on the Famennian stage.
Sandstone's formation :
A detrital rock is a rock formed by the accumulation of sediments, so sandstone comes from the accumulation of sand banks deposited at the bottom of the sea that undergo the phenomenon of sedimentation: under their own weight, these deposits are packed and gradually sunk (phenomenon of subsidence).
By diagenesis (all chemical and mechanical processes that affect a sedimentary deposit), the sand grains are cemented by precipitation and crystallization of dissolved salts in the pore water.
If the degree of cementation is weak, the rock is so friable as if it's high, the rock is hard and consistent.
Sandstone is then, a sedimentary rock composed of grains of sand (quartz or silica) connected by a variable nature of cement (siliceous, calcareous or ferruginous) which the quality and color of the sandstone depends on: clear or yellowish white to grayish, the sandstone can also be colored in yellow, red or green by iron oxides.
The sandstone can sometimes be hillock: its surface has bumps.
Reminder on "Earthcaches": There is no container or logbook on the given coordinates. Just visit the site and answer the questions by e-mail.There is no need to wait for my reply, feel free to log immediately after. If the answers are incorrect, I will let you know. Happy caching!
To validate your visit:
1-. Which sandstone was used to built Lewarde's Church?
2-. Which nickname was given to the stone carvers of Lewarde? Why do you think it is so?
3-. Which form is drawn under your feet with stone blocks in front the church's door?
4-. What can we find in the sandstone wall at the left side of the church's door? From what it was formed?
5-. What can you see on the two pillars at the entrance of the church's gardens? At what height?
6-. What is the distinctive feature of the sandstone block you can find in the photo of the listing?
Pour faciliter vos recherches, sur la photo jointe au descriptif, les zones numérotées correspondent aux zones où vous pourrez trouver les réponses aux différentes questions.
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