Why is molten lava hot

The pool of magma in a magma chamber is layered. The least-dense magma rises to the top. The densest magma sinks near the bottom of the chamber. Over millions of years, many magma chambers simply cool to form a pluton or large igneous intrusion.

If a magma chamber encounter s an enormous amount of pressure, however, it may fracture the rock around it.

The cracks, called fissure s or vents, are tell-tale signs of a volcano. Many volcanoes sit over magma chambers. An eruption reduce s the pressure inside the magma chamber. Large eruptions can nearly empty the magma chamber.

The layers of magma may be document ed by the type of eruption material the volcano emits. Gases, ash, and light-colored rock are emitted first, from the least-dense, top layer of the magma chamber.

Dark, dense volcanic rock from the lower part of the magma chamber may be released later. In violent eruptions, the volume of magma shrinks so much that the entire magma chamber collapses and forms a caldera. All magma contains gases and a mixture of simple element s. Being that oxygen and silicon are the most abundant elements in magma, geologists define magma types in terms of their silica content, expressed as SiO 2.

These differences in chemical composition are directly related to differences in gas content, temperature, and viscosity. This type of magma has a low gas content and low viscosity, or resistance to flow. Mafic magma also has high mean temperatures, between o and o Celsius o and o Fahrenheit , which contributes to its lower viscosity. Low viscosity means that mafic magma is the most fluid of magma types. This lava cools into basalt , a rock that is heavy and dark in color due to its higher iron and magnesium levels.

The Hawaiian Islands are a direct result of mafic magma eruptions. This results in a higher gas content and viscosity. Its mean temperature ranges from o to o Celsius o to o Fahrenheit. This more gaseous and sticky lava tends to explode violently and cools as andesite rock. Intermediate magma most commonly transforms into andesite due to the transfer of heat at convergent plate boundaries.

Andesitic rocks are often found at continent al volcanic arcs, such as the Andes Mountains in South America, after which they are named. As a result, felsic magma also has the highest gas content and viscosity, and lowest mean temperatures, between o and o Celsius o and o Fahrenheit. These trapped bubbles can cause explosive and destructive eruptions.

These eruptions eject lava violently into the air, which cools into dacite and rhyolite rock. Much like intermediate magma, felsic magma may be most commonly found at convergent plate boundaries where transfer of heat and flux melting create large stratovolcano es. Magma exists as pockets and plumes beneath the surface of the Earth.

Photograph by Carsten Peter, National Geographic. Mysterious Magma. Magma is usually studied as lava or igneous rock. In , the Icelandic Deep Drilling Project created a well that uses magma to generate geothermal energy. Normally, geothermal energy is created by pumping water into hot volcanic bedrock, creating steam that is then harnessed to generate electricity.

This huge increase in temperature allowed just one magma well to generate roughly 36 megawatts of electricity, powering 36, homes. In comparison, one single wind turbine generates between 1 to 3 megawatts. Also called a collision zone. Also called the average. Also known as a composite volcano. Media Credits The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.

Media If a media asset is downloadable, a download button appears in the corner of the media viewer. Text Text on this page is printable and can be used according to our Terms of Service. Interactives Any interactives on this page can only be played while you are visiting our website. Oct 27, May 12, Did you find your answer in the article, Dutin? Andrew Apr 20, Apr 20, Tord Larsson Apr 13, Apr 13, Mar 31, Music really does a lot to set the scene.

Maybe we should do a Wonder about that? Lava bro Mar 30, You're welcome, Lava bro. Ryan Mar 30, Can you find Lava anywhere aother than inside a volcano or from one???????? Mar 30, In lamps? TIKZ Mar 28, Mar 29, Drew Mar 27, Mar 27, Thanks for the head's up, Drew.

That's good looking out. Andrew Mar 27, Mar 24, Jackson Mar 23, I found it interesting that the red and orange part of lava is cooler than the white part which is hotter. Mar 23, Connor Mar 23, I thought that lava can get up to 2, degrees was cool. NAthan Mar 23, How can we help you, Nathan? Dominic Mar 23, That was teally cool and swag and dope and beastmode!!!!!! Thanks for all the compliments, Dominic! Chuggingtion Mar 22, Mar 22, Gavin Mar 21, Not sure how to answer that one, Gavin.

Mar 21, Glad you liked this one, Janessa! It was pretty "cool" learning about it, huh? I Love lava! A valcano will erupt on top of you in Glad you liked this one, Antonio! Lava has been a hot topic lately. Nathan Mar 20, Mar 20, Glad you liked it, Nathan!

Gavin Mar 20, Or maybe really hot? Feb 17, Feb 3, What's up, Ignacio? How did you like this lava Wonder? Unomoness Jan 26, Wonderer Jan 26, Jan 26, Hi, Unomoness! Thanks for greeting the people! Jan 15, Taylah Mar 20, TJ Maldonado Jan 26, That is sooooo cool i want too see a fat volcano :O. Jan 19, Chloe Jan 19, The video is sadly I love this is so cool!!!!!!!!!!!!!!!

So glad the video lived up to your expectations! We aim to please here at Wonderopolis! Mailee Jan 19, I love learning about lava and Other stuff to!!! Awesome, Mailee! We love learning new things, too! Hey Wonderopolis!!!!!! I have NOT seen the video yet but just looking at it looks so cool! This video looks way cooler then the What is a Volcano video! HeadshotGenerations Dec 14, Dec 14, Heehee, for sure, HeadshotGenerations! Toasty Dec 13, Dec 13, Thanks for letting us know how you feel, Toasty!

LALA Dec 2, Dec 2, Aaron Dec 2, Dec 4, Travis Dec 2, Thanks for sharing what you thought of this Wonder, Travis.

Queen Eleinen el-in-nin of R May 13, Oct 28, May 18, Feb 9, Yes, it is, kyrra! We hope you learned more about lava from reading this Wonder!

Feb 4, Mar 3, Jan 20, Dec 3, Oct 16, Amelia May 6, Lava is really hot!!!! Gnarly wonder dude and dudettes!! Carleigh Oct 21, Oct 23, For sure, Carleigh! Wonderopolis May 6, Niko Davison Nov 25, I never knew that.

Wonderopolis Nov 26, We're glad you learned something new with us, Niko! Thanks for stopping by Wonderopolis! Emma Apr 8, Wonderopolis Apr 8, Vincent's Class Mar 20, Rhyolitic magma is high in potassium and sodium but low in iron, magnesium, and calcium. It occurs in the temperature range of about o C to o C o F to o F. Both the temperature and mineral content of magma affect how easily it flows. The viscosity thickness of the magma that erupts from a volcano affects the shape of the volcano.

Volcanoes with steep slopes tend to form from very viscous magma, while flatter volcanoes form from magma that flows easily. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.

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