This EarthCache takes you to Rigg War Memorial, it commemorates the War dead of both World Wars. It is carved from Dalbeattie granite.
Please be respectful to the memorial and the location.
🤔 What is granite?
Granite is a common type of igneous rock. Igneous rock is one of the three main rock types , the others being sedimentary and metamorphic. Igneous rock is formed through the cooling and solidification of magma or lava. Igneous rock may form with or without crystallisation either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks. Granite can be white, pink, or gray in colour, depending on their mineralogy. Granitic rocks mainly consist of feldspar, quartz, mica and amphibole minerals, which form an interlocking matrix of feldspar and quartz with scattered darker biotite mica and amphibole (often hornblende) peppering the lighter colour minerals.
🤔 We are here to examine a feature in the granite.
We are here to look at a Xenolith. Xenoliths are odd shaped, which are a different colour than the bulk of the granite rock. Xenolith is greek for a foreign rock, bascially it is a piece of rock trapped in magma. As explained above, granite is an igneous rock, this is a type of rock formed through the cooling and solidification of magma. A xenolith is a rock embedded in magma while the magma was cooling. As the molten material rises, it tears off bits and pieces of the magma pipe, or roof / wall of a pluton in which it was travelling in which it is traveling. These bits and pieces, trapped in the magma but not melting into it, become xenoliths. Crystals that are torn from the sides of magma pipes are called xenocrysts. As the magma flows out on to the surface of the Earth, or remains as a body within the crust, it is cooled, and various types of igneous rocks could be formed. Xenoliths usually have a different colour and density when compared to the surrounding rock, they can be small or large.
The specific xenolith we are interested in is above the lettering the memorial.
This being an EarthCache, in order to log it, I ask that you answer the below questions. Please send them to me, and do not include them in your log. You can send them to me by using the message facility or email, both of which can be found by looking at my profile.
1. Please describe the xenolith, in terms of shape and size.
2. Please explain how the xenolith has come to be here.
If anybody would like to expand to this series please do, I would just ask that you could let Just-Us-Two know first at justustwo1013@gmail.com so they can keep track of the memorial numbers and names to avoid any duplication.