Examples of historic pyroclastic flows
By: Blaise Pascal
Other than causing tsunamis, creating lava flows, and pouring ash and gases into the air, volcanoes can be deadly in another way. Pyroclastic flows sometimes result from an eruption and can cause massive damage and loss of life. These flows can move at incredible speeds...
By: Keith Redfern
A volcanic intrusion occurs when molten material intrudes between or through beds of rock in the Earth’s crust.Volcanic activity occurs along the lines between tectonic plates. Tectonic plates are separate areas of the Earth’s crustal rocks which move over time. There are...
By: Jennifer Boyd
There are several different types of volcanoes but the one that forms some of the largest volcanoes in the world belongs to the group called “shield volcanoes.” A shield volcano can be as wide as three or four miles, and can stand as...
By: Elizabeth M Young
During the middle Pleistocene era, there were two oceanic plates: the Kula and Farallon plates. About 300,000 to 360,000 years ago, these two plates were subducted, or pushed beneath the western edge of the North American Plate and created a volcanic mountain that...
By: Eric Lannak
The emerald’s dark green color and shine have long made it a coveted and valuable stone. The first known emerald mines were in Egypt, dating to the fourth century BC, and Cleopatra used emeralds in her jewelry. The ancient Greeks likewise prized it, and...
By: Gareth Carmichael
Volcanic eruptions are one of the many splendid wonders Earth has to offer. Yes, they are devastating; yes they are, undeniably, natural disasters. That does not stop them from being truly magnificent to behold. Toxic plumes rising in the sky, competing with the densest of...
What are the traits of a shield volcano?
By: Keith Redfern
The most obvious trait of a shield volcano is its shape, which is gently sloping with an immensely wide base. A shield volcano is one from which mainly lava flows, and its shape relates directly to the acidity of its lava, which is alkaline.Along...
By: CJ Han
According to National Geographic, “Two important traits that characterize volcanoes are explosiveness and viscosity” (“Forces of Nature-Volcanoes”, 1996). Shield volcanoes are not explosive because they have basaltic magma with low viscosity. They also have low slopes connected to a central vent that form...
By: M E Skeel
When a volcanic eruption is imminent, the volcano will often eject tonnes of volcanic ash into the atmosphere. This material is produced by the explosive conditions in the volcano and is not a product of combustion, so the term ash is not accurate. Instead the...
By: Blaise Pascal
Granite is a very common type of rock that has been, and is still used for a variety of purposes. Its strength makes it an excellent building material used in the past and in the present, and it isn’t very porous or affected by...

 

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