USGS Multimedia Gallery
[music fades in]
Welcome to CoreFacts, where we're always short on time and big on science. I'm Danielle Eganhouse. Today's question is an interesting one.
What is the difference between "magma" and "lava"?
Scientists use the term magma for molten rock underground and lava for molten rock that breaks through the Earth's surface. Originating many tens of miles beneath the ground, magma commonly contains some crystals, fragments of surrounding (unmelted) rocks, and dissolved gases, but it is primarily a liquid composed principally of oxygen, silicon, aluminum, iron, magnesium, calcium, sodium, potassium, titanium, and manganese. Lava is red hot when it pours or blasts out of a vent but soon changes to dark red, gray, black, or some other color as it cools and solidifies. Very hot, gas-rich lava containing abundant iron and magnesium is fluid and flows like hot tar, whereas cooler, gas-poor lava high in silicon, sodium, and potassium flows sluggishly, like thick honey in some cases or in others like pasty, blocky masses.
And now you know. Join us again every weekday for a new CoreFact. For other CoreFacts, or for CoreCast, our in-depth science podcast, go to usgs.gov/podcasts. If you'd like to have a question featured on our show, give us an email at firstname.lastname@example.org or a phone call at 703-648-5600. Remember, long distance fees do apply.
CoreFacts is a product of the U.S. Geological Survey, Department of the Interior.
[music fade out]
Title: What is the difference between "magma" and "lava"?
Description: Listen to hear the answer.
Date Recorded: 6/24/2008
Usage: This audio file is public domain/of free use unless otherwise stated. Please refer to the USGS Copyright section for how to credit this audio.
Suggest an update to the information/tags?