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Phaneritic or not Phaneritic? That is the question

A cache by jazzyjessups Send Message to Owner Message this owner
Hidden : 03/04/2019
Difficulty:
2.5 out of 5
Terrain:
1 out of 5

Size: Size: other (other)

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Geocache Description:


This is a simple EarthCache with the educational element about the Phaneritic classification of Rock. 

 

The listed coords will bring you to the Steeple Morden Airfield War memorial. The picture below will ensure that you are in the correct place. My Jeep may not actually be parked there- but you can't miss the propeller.

At the Memorial you will see a piece of Granite on which you will be asked to answer some questions. But first the Earth science.

 

What is an Igneous Rock? An Igneous rock is  formed by the cooling of Molten rock. Igneous rock comes in two categories:  1. Intrusive and 2. Extrusive.  

 

1. Intrusive Igneous rock occurs when the cooling of molten rock occurs under the Earth's surface. As it cools under the Earth's surface it cools slowly which enables large crystals to form. The slower the cooling the larger the crystals form.

 

2. Extrusive Igneous rock occurs when the molten rock cools on top of the Earth's surface. As the rock is exposed to the Earth's elements such as rain etc the rock cools quickly and if crystals form they are usually quite small. Often not visible to the naked eye.

 

What is Phaneritic Rock? A Phaneritic rock is an igneous rock whose microstructure is made of crystals large enough to be distinguished by the naked eye.The Phaneritic microstructure is formed undergound when the molten rock cools and crystals grow.

 

What is Granite? Granite is a Crystalline (Contains crystals) igneous rock which is made mainly of Quartz, feldspar and mica.

 

Alkali Feldspar Granite: Alkali Feldspar Granite (many varieties known as "red Granite") is an igneous rock which is high in elements and also a Granite which is high in mineral potassium feldspar (K-Spar). The large quantity of K-spar gives the rock it's pinky red appearance.

 

 
A Phaneritic rock is an igneous rock whose microstructure  is
made of crystals large enough to be distinguished by the naked eye. The Phaneritic
microstructure is formed when magma deep underground cools slowly. The slower the cooling of
the rock the larger the crystals have time to grow.

 

So to the questions:

 

In front of the memorial and under the propeller you will find a piece of granite which is mounted on concrete. Please study the rock and answer the questions below. One can either e-mail me or message me with your answers. One can also log a find immediately after doing so. I will contact the cacher if I feel the questions have not been answered satisfactory.

 

Question 1.  Please tell me the dimensions of the piece of granite.

Question 2.  Please describe the piece of granite in terms of colour and mineral content.

Question 3.  What percentage of the rock would you say is Feldspar?

Question 4.  Do you think it is K-spar? Please justify your answer.

Question 5.  Do you think this rock is Phaneritic? Please justify your answer

Question 6. Please tell me what is written on top of the Granite.

Question 7. (Optional) To show you have visited the memorial - please take a photo of yourself or GPS with the propellor.

So what is a Phanerite Rock?
A Phanerite rock is an igneous rock whose microstructure  is
made of crystals large enough to be distinguished by the naked eye. The Phaneritic
microstructure is formed when magma deep underground cools slowly. The slower the cooling of
the rock the larger the crystals have time to grow.
So what is a Phanerite Rock?
A Phanerite rock is an igneous rock whose microstructure  is
made of crystals large enough to be distinguished by the naked eye. The Phaneritic
microstructure is formed when magma deep underground cools slowly. The slower the cooling of
the rock the larger the crystals have time to grow.
So what is a Phanerite Rock?
A Phanerite rock is an igneous rock whose microstructure  is
made of crystals large enough to be distinguished by the naked eye. The Phaneritic
microstructure is formed when magma deep underground cools slowly. The slower the cooling of
the rock the larger the crystals have time to grow.
References: Forbes.com, Geology.com, Wikipedia.

Additional Hints (Decrypt)

Va sebag bs ovt cebcryyre

Decryption Key

A|B|C|D|E|F|G|H|I|J|K|L|M
-------------------------
N|O|P|Q|R|S|T|U|V|W|X|Y|Z

(letter above equals below, and vice versa)



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