Q:

What is the difference between magma and lava?

A:

Magma and lava are the same substance in two different forms. Magma is molten rock that is found beneath the earth's crust, while lava is what magma becomes once it reaches the surface and erupts from a volcano or crack in the earth.

Magma can also contain many other components besides just molten rock, including gases and crystals. This mixture maintains a temperature between 1,600 and 2,400 degrees Fahrenheit. The molten rock often contains silicon, iron, carbon, aluminum, magnesium and different alkalis. Magma is heated by geothermal convection and pressure. Typically, it is found several kilometers beneath the earth's surface.

The composition of lava determines whether its flow is explosive, fast-moving or slow and highly viscous. Temperature plays a less significant role in the look and feel of the volcanic rock that forms once the lava cools down. Pumice is one igneous volcanic rock that is shaped by its composition and the type of eruption. As lava violently shoots into the atmosphere, it rapidly cools and decompresses, allowing air bubbles to permeate the rock, leaving a bubble-marked texture and a light weight. Obsidian, on the other hand, is a high-silica rock that forms from quick-cooling lava found on the ground in highly viscous flows.


Is this answer helpful?

Similar Questions

  • Q:

    What is magma made out of?

    A:

    Magma is a liquefied mixture of rock, crystals and dissolved gas. While this fits the general description of magma, it has three distinct observed types: basaltic, rhyolitic and andesitic.

    Full Answer >
    Filed Under:
  • Q:

    What is a volcanic neck?

    A:

    A volcanic neck, also called a lava neck or volcanic plug, is a cylindrical-shaped volcanic landform created when magma hardens inside the vent of a volcano, according to the University of Wisconsin. Examples of volcanic necks include Devil's Tower in Wyoming, Lizard Head in Colorado and Morro Rock in California.

    Full Answer >
    Filed Under:
  • Q:

    How does a volcanic neck form?

    A:

    A volcanic neck forms when lava inside a caldera cools after magma stops feeding the mountain, and then the outside of the extinct volcano erodes after millions of years. The cooled lava remains intact because it is harder than the surrounding rock that eroded. Perhaps the most famous volcanic neck in the United States is Devil's Tower in Wyoming.

    Full Answer >
    Filed Under:

Explore