What makes an eruption explosive?
If there is a lot of silica and a lot of water than the eruption will be explosive.
What makes an eruption non-explosive?
For an eruption to not be explosive it has to have only a little silica nad wtaer.
How are explosive and non-explosive eruptions different?
Non-explosive eruptions have lava flows while explosive eruptions shoot molten rock into the air.
What is produced by a non-explosive eruption?
Non-explosive eruptions form land and enlarge the volcanoes because there are continuous lava flows.
What is produced by explosive eruptions?
Explosive eruptions cause damage and shrink volcanoes.
What are some examples of pyroclastic material?
Volocanic blocks, Volcanic bombs, Lapilli, Volcanic ash
What are some examples of lava?
Blocky lava, Pahoehoe, Aa, Pillow Lava
True or False: Volcanic blocks are the biggest type of pyroclastic material.
What are volcanic bombs?
Volcanic bombs are pieces of pyroclastic material that harden in the air and flattened into a bomb shape.
What is Lapilli?
Lapilli is pyroclastic material that hardens in the air and is small like pebbles.
What is Blocky lava?
Blocky lava usually stays near the volcano and looks like a huge block.
What is Pahoehoe?
Pahoehoe is lava that flows slowly like wax.
What is Aa?
Aa is a type of lava that has a brittle crust and the lava underneath the crust continous to move.
What is pillow lava?
Pillow lava is formed when there is an eruption underwater. The pillow lava looks like a pillow but it's actually very hard.
What are positive effects of an explosive eruption?
Positive effects are that more land is built and the soil becomes evry fertile!
What are the negative effects of an explosive eruptions?
It can block the sun for days, it can kill plants-animals-people,
What is an extinct volcano?
An extinct volcano is a volcano that has no record of erupting. It is also a volcano that is showing no signs of erupting soon.
What is a dormant volcano?
A dormant volcano is a volcano that has erupted in the past and is showing signs of possibly erupting in the future. (asleep)
What is an active volcano?
An active volcano is a volcano that has erupted in the
What do scientists use to predict volcanic eruptions?
Scientist use satellites, thermal pictures, tillmeter, seismograph,
How do scientist predict volcanic eruptions?
Scientist use a tillmeter to see if there is a bulge, a seismograph to see if there is any seismic activity, ect.
What can a hot spot form?
It can form an island chain.
What is a hot spot?
A hot spot is a place on the earth's crust right above a mantle plume.
Where are most volcanoes found?
Most are found on tectonic plate boundaries, convergent/divergent boundaries, but most oftenly on the Ring of Fire.
How do volcanoes form on divergent boundaries?
At a divergent boundary there is a rift. This rift decreases pressure and this release of pressure causes an eruption which will eventually form a volcano.
How do Volcanoes form on a convergent boundary?
At a convergent boundary because the oceanic plate goes under the continental plate and melts. This melting oceanic plate forms magma which causes an eruption which will eventually form a volcano.
What are some characteristics of a shield volcano?
Non-Explosive, gently sloping sides, enormous, wide base, Example: Mauna Kea
How does a shield volcano get its shape?
It gets its shape from layers of very runny lava.
What are some characteristics of a cinder cone volcano?
steep sides, narrow base, small, occur in clusters, erode quickly, erupt for short periods of time, Example: Paricutin
How does a cinder cone volcano get its shape?
It gets its shape from pyroclastic material that comes from moderatly explosive eruptions.
What are some characteristics of a composite volcano?
broad base, steep sides, most common, also known as a stratovolcano, medium or large, Example: Japan's MT. Fugi
How does a composite volcano get its shape?
It gets its shape from explosive eruptions of pyroclastic materials followed by quieter outpourings.
How does magma form?
There is a constant temperature so when there is a release in presure the ro9ck will melt into magma.
a hole or crack in the earth's crust through which magma rises to the surface
the hot liquid that forms when rock partially or completely melts; may include mineral crystals
magma and fragments of rock that are ejectedinto the atmosphere during a violent volcanic eruption
magma that erupts onto the earth's surface
a mountain that forms when lava or pyroclastic material builds up around a volcanic vent
a large, gently sloped volcano that forms repeated, non-explosive eruptions of lava
a small, steeply sloped volcano that forms from moderatly explosive eruptions of pyroclastic material
Cinder Cone Volcano
a volcano made of alternating layers of lava and pyroclastic material; also called a stratovolcano
a funnel-shaped pit around the central vent of a volcano
a circular depression that forms when a magma chamber empties and causes the ground above to sink
a zone of thin, fractured lithosphere that forms between tectonic plates as they seperate
a place on Earth's surface that sits directly above a rising column of magma called a mantle plume
What were the signs that Mount St. Helens was becoming active and might erupt again? (the spring of 1980)
There was smoke and gases that were coming out of Mount St. Helens and there had also been various little earthquakes. Ther was also a slight bulge.