Tectonic Plates
Where are earth’s tectonic plates
Under the continents and oceans
What is magma
Melted (molten) rock
What do volcanos release that make them like safety valves?
Pressure from the collision of the plates below
What is an active volcano?
One that is erupting right now.
If boiling water heated by magma shoots out of cracks in the earth’s crust, what is it called? riser or geyser?
Geyser.
What do the plates sit on
A layer of molten magma
Where is magma found on our planet?
Below the earth’s crust.
T or F: Volcanos form when hot magma squeezes up through weak spots in earth’s crust?
True
T or F: A dormant (sleeping) volcano will never erupt again.
False: It is expected to erupt sometime in the future but no one knows when.
T or F: Old Faithful is a geyser that shoots about 10 gallons of steam into the air each time it erupts?
False. It shoots at least 2500 gallons of steam many times a day.
What makes the plates move around and bump into each other?
Hot magma
Which is hotter - boiling water or magma?
Magma. It can reach 1100 degrees or more.
Where would it be likely to find the weak spots in the earth’s crust that allow volcanos to form?
Where plates meet.
Is an extinct volcano expected to erupt again?
No. It has never erupted in human history.
Mount Saint Helens eruption caused the largest __________ in history?
Landslide
What builds up underground when the plates collide with each other?
Pressure
What is magma called after it flows out onto the ground?
Lava
T or F: A volcano eruption lasts only a few minutes?
False. Eruptions can last for day or months,
What did Krakatoa island eruption cause that killed 36,000 people on nearby islands?
100 foot tsunami
Can the same volcano erupt many times over many centuries?
Yes.
When rock above pressure caused by the plates colliding fractures, pressure (energy) is released suddenly and the ground shakes. What is this shaking called?
Earthquake
What’s another word for hardens in the sentence: Lava hardens into rock.
Cools
How are mountains formed from erupting volcanos?
Ash and fiery rock spew out the top, and eventually pile up and harden into a mountain
T or F: The Mount Saint Helens eruption created temperatures that were only a few degrees above where water boils?
False. Water boils at 212 degrees and the volcano’s temperatures where at least 1,100 degrees - more than 5 times boiling water.
T or F: Old Faithful and The Grand Canyon are both in Yellowstone park Which is in the far west of the United States.
True. Yellowstone Park is so big (3,468 square miles) that it falls in some part of each of the three states Wyoming, Montana, and Idaho.