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The main eruption of 1980 released ash, pumice, and gas. Smaller eruptions that occurred later produced very viscous lava that piled up into a lava dome.
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How does the viscosity affect of lava affect its flow rate?
Viscosity means how runny it is. Thus a lava with low viscosity will erupt fast and form long, wide spreading lava flows (eg Hawaii) and lavas of high viscosity will erupt slowly and form lava domes (eg Mt. St. Helens).
What caused mtshasta to erupt?
Mt Saint Helens was caused to erupt because when two plates collided together-the continential (named:North American Plate) was forced over the oceanic crust (named: Juan De Fuca) causing the top of the moutain to blow over the side of the mountian. The oceanic crust goes deeper and deeper into the continential crust that when soon it reaches the lithosphere (the mantle) causing it to melt into lava. Then the hot pressure shoots up the magma chamber and shoots out the top causing mt saint helens. Mt saint helens erupted on May 18, 2000 in Skamania County in Washington. This explosion cause tons of ash, hot rock, and gas. Over 57 people were sadly killed in this eruption. The mountain range that mt saint helens was located on was the Cascade Range which was firts descovered by Thomas J. Dryer. Mt saint helens was a Plinian volcanoe, which meaning when it explodes there is not much lava spewing from the top. It is mostly ash coming out over 5 miles per hour out of the volcanoe. Mt saint helens is now dead in the year of 2013. but it did last erupt in june 10, 2004. -sydney
What type of lava comes from what volcano?
Shield volcanoes will erupt basaltic lava. Cinder cones erupt basaltic lava or basaltic andesite lava. Stratovolcanoes often erupt andesite lava, but may erupt basaltic or rhyolitic lava and all intermediate types as well.
What type of valcano is Mount Saint Helens?
Mt. Saint Helens is a composite volcano. Composite volcanoes are formed by some alternating layers of tephra (rock debris thrown into the air by volcanic eruptions) and lava. Composite volcanoes usually erupt violently and are large and steep-sided.
Do cinder cones erupt felsic or mafic lava?
Composite volcanoes can erupt both mafic and felsic material, but intermediate material is the most common.
How does the viscosity affect of lava affect its flow rate?
Viscosity means how runny it is. Thus a lava with low viscosity will erupt fast and form long, wide spreading lava flows (eg Hawaii) and lavas of high viscosity will erupt slowly and form lava domes (eg Mt. St. Helens).
On Mount Saint Helens the hot lava melted the snow and caused a?
On Mount Saint Helens, the hot lava melted the snow and ice, and it caused surges of water that eroded and this mixed with loose rock debris. This created volcanic mudflows or lahars.
Does lava exit only through summit vents?
No. In some cases (like the mid-atlantic ridge), lava can erupt through rifts instead of the summit of a volcano; in other cases, such as Mount St. Helens, the 'lava' can erupt explosively and destructively through the side of a conical volcano.
What caused mtshasta to erupt?
Mt Saint Helens was caused to erupt because when two plates collided together-the continential (named:North American Plate) was forced over the oceanic crust (named: Juan De Fuca) causing the top of the moutain to blow over the side of the mountian. The oceanic crust goes deeper and deeper into the continential crust that when soon it reaches the lithosphere (the mantle) causing it to melt into lava. Then the hot pressure shoots up the magma chamber and shoots out the top causing mt saint helens. Mt saint helens erupted on May 18, 2000 in Skamania County in Washington. This explosion cause tons of ash, hot rock, and gas. Over 57 people were sadly killed in this eruption. The mountain range that mt saint helens was located on was the Cascade Range which was firts descovered by Thomas J. Dryer. Mt saint helens was a Plinian volcanoe, which meaning when it explodes there is not much lava spewing from the top. It is mostly ash coming out over 5 miles per hour out of the volcanoe. Mt saint helens is now dead in the year of 2013. but it did last erupt in june 10, 2004. -sydney
How was mount st Helen erupted?
Mt. St. Helens erupted by the pressure to make a volcano explode. Lava originates deep below the Earth's surface where it is still extremely hot, with magma at the bottom of the lava. a 5.1 earthquake triggered mt st helens to erupt
What made mt st Helens so explosive?
Mount Saint Helens' magma/lava composition is different to many volcanoes and is about 64%silica and 4% water.
Can a stratovolcano erupt blocky lava?
Yes. Stratovolcanoes can erupt blocky lava flows, basaltic lava flows, or may erupt explosively.
What type of lava comes from what volcano?
Shield volcanoes will erupt basaltic lava. Cinder cones erupt basaltic lava or basaltic andesite lava. Stratovolcanoes often erupt andesite lava, but may erupt basaltic or rhyolitic lava and all intermediate types as well.
Where do more active volcuranos ocurr?
Active volcanoes are found on mainly plate margins, with the few examples of hot spots all over the place (e.g. Moana Loa on Hawaii). Volcanoes found at constructive plate margins are more effusive and erupt basaltic lava (e.g. Iceland) and volcanoes found NEAR destructive plate margins are explosive and erupt either andesitic or rhyolitic lava (e.g. Mount Saint Helens-however this volcano might not erupt for quite a while whereas the other two example erupt very frequently).
Is Mt St Helens a lava dome?
No. Mount St. Helens is a stratovolcano. There is a lava dome in the crater.
What type of valcano is Mount Saint Helens?
Mt. Saint Helens is a composite volcano. Composite volcanoes are formed by some alternating layers of tephra (rock debris thrown into the air by volcanic eruptions) and lava. Composite volcanoes usually erupt violently and are large and steep-sided.
Why do some volcanoes erupt while others erupt quietly?
This is because of the time of volcano it is and the type of lava it excretes. A steep volcano will erupt with basaltic lava which is runny and can clog at the top. A shield volcano, however is different as the thick lava emitted just glops onward.
