For the resolution
For the resolution, go to the rocky parish level.
Log on to âFound Itâ and send me your answers via the geocaching messaging system (Message Center) or via mail. Be sure to indicate the name of the cache! I'll analyze your answers and contact you if I have any problems.
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> Questions <
1. Look carefully at the pink area
1.1. Describe the rock you can see (texture, grain thickness, etc.)
1.2. Is this area a lava flow ?
2. Look carefully at the green area
2.1. Describe the rock you can see (texture, grain thickness, etc.)
2.2. What differences do you observe compared to the pink area ?
To validate the Earth you must attach to your log a photo of yourself (it is not necessary to show a photo of your face) in the park (do not show the location of the Earth)
You don't need to send me your photo by email, I will contact you if there is any problem.
Any log not accompanied by this photo will be deleted.
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> Hell's Hollow Park <
South of the city, between the districts of La Fontaine-du-Bac and Landais, its volcanic origins make it a unique place where pozzolana, volcanic bombs and final lava flows emerge from the vegetation. Its four hectares of rolling meadow invite you to stroll among hazel trees, conifers and other rose bushes.
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> Why rocks here? <
The Puy de Gravenoire is a cone directly overlooking the village of Royat, 4 km southwest of Clermont-Ferrand, cut by an old quarry. It is located 8 km east of the range. From the foot and the flank several flows depart, one to the north, 1 km long towards Royat and the Tiretaine valley and the others towards the east over 6 km, carrying the town of Beaumont, then separating into two tongues and going to cover the plateaus of St Jacques and CĂ©zeaux between Clermont-Ferrand and AubiĂšre. The debris avalanche from the Puy de Gravenoire covered an area where 30,000 inhabitants currently live. One of the ends of one of the flows is visible in the Creux de l'Enfer park (block of eroded basalts)
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> What is basalt? <
Basalt is a type of volcanic rock that forms from the solidification of molten lava. It is an igneous rock, meaning it was formed by the cooling and solidification of magma or lava. Basalt is one of the most common rock types on Earth and is found in various locations around the world, both on land and beneath the ocean floor.
Basalt is known for its dark color, typically ranging from black to dark gray, and its fine-grained texture. It is composed primarily of minerals such as pyroxene, plagioclase, feldspar, and sometimes olivine. Basalt can have a range of compositions, but is generally rich in iron and magnesium, and low in silica.
Basalt possesses several unique properties that make it useful for various applications. For example, it is known for its durability, strength, and resistance to wear and erosion, making it ideal for construction materials such as road aggregates, concrete, and building stone. Basalt is also used to manufacture fiber reinforcement materials, known as basalt fiber, which are used in a wide range of applications, including automotive parts, aerospace components, and sporting goods.
Basalt also has significant geological significance. It is a common rock type in volcanic regions and is associated with volcanic activity, such as volcanic eruptions and lava flows. Basalt lava flows, in particular, can cover large areas of land and create vast basalt plateaus, such as the Columbia River Plateau in the United States and the Deccan Traps in India. These plateaus have significant impacts on the local landscape, ecology and geology.