Magma

The rock is pulled down by movements in the earth’s crust and gets hotter and hotter as it goes deeper. It takes temperatures between 600 and 1,300 degrees Celsius (1,100 and 2,400 degrees Fahrenheit) to melt a rock, turning it into a substance called magma (molten rock).

Decompression melting takes place within Earth when a body of rock is held at approximately the same temperature but the pressure is reduced. This happens because the rock is being moved toward the surface, either at a mantle plume (a.k.a., hot spot), or in the upwelling part of a mantle convection cell.

The factors that mainly affect in the formation of magma can be summarized into three: Temperature, Pressure and composition.

Wet and Dry Melting In order for magma to form, wet or dry melting of rocks or minerals must occur. Dry melting occurs when minerals or rocks, with no carbon dioxide or water in them, are heated to a specific temperature. This temperature increases as pressure in the Earth’s layers increases.

Magma can rise when pieces of Earth’s crust called tectonic plates slowly move away from each other. The magma rises up to fill in the space. When this happens, part of Earth’s crust can be forced deep into its interior. The high heat and pressure cause the crust to melt and rise as magma.

Magma cools and crystallizes to form igneous rock. Igneous rock undergoes weathering (or breakdown) to form sediment. As the sedimentary rock is buried under more and more sediment, the heat and pressure of burial cause metamorphism to occur. This transforms the sedimentary rock into a metamorphic rock.

Plutonites , plutonic rocks or deep rocks are igneous rocks that are formed at great depths through extremely slow cooling of magmas . The resulting rock bodies, which can reach the earth’s surface through uplift processes and erosion, are called plutons or, if they reach very large dimensions, batholiths .

Since the lower mantle is the source of the magma, this means no more magma production. Though it will take a very long time for the earth to completely cool down. A billion years, if not more.

This will make life on Earth very difficult for human beings and other life forms. When the Earth has cooled completely, the movement in the mantle will also stop eventually. Then, the plates on the surface will no longer move and there will be fewer earthquakes and volcanic eruptions.

More than 80 percent of the Earth’s surface–above and below sea level–is of volcanic origin.

Molten material beneath the crust of the earth is called magma. A common misconception is that magma comes from the Earth’s molten core. It really comes from the mantle, the layer between the core and the crust. The mantle is solid, but it shifts and becomes fluid due to changes in temperature and pressure.

A dormant volcano is an active volcano that is not erupting, but supposed to erupt again. An extinct volcano has not had an eruption for at least 10,000 years and is not expected to erupt again in a comparable time scale of the future.

“What we are now saying is that with just a trace of carbon dioxide in the mantle, melting can begin as deep as around 200 kilometers. “When we incorporate the effect of trace water, the magma generation depth becomes at least 250 kilometers.”

The explosion of the Mount Toba supervolcano, located on the modern island of Sumatra, some 74,000 years ago, was Earth’s largest eruption in the past 28 million years.

Assab, a small port city in the Red Sea region of Eritrea, ranks as the hottest city in the world, according to climate data.

Death Valley

108.14°F