What is the smallest tephra?
What is the smallest tephra?
Stack #814034
| Question | Answer |
|---|---|
| rock fragments thrown into the air during a volcanic eruption is___ | tephra |
| the smallest tephra are___ | dust |
| fast moving clouds of gas ash and other tephra are___ | pyroclastic flows |
| what forms when the top/side of a volcano collapses into magma chamber? | caldera |
Which type of volcano is a small type of volcano with steep sides and made of loose particles?
stratovolcanoes
What are the four types of tephra?
Classification
- Ash – particles smaller than 2 mm (0.08 inches) in diameter.
- Lapilli or volcanic cinders – between 2 and 64 mm (0.08 and 2.5 inches) in diameter.
- Volcanic bombs or volcanic blocks – larger than 64 mm (2.5 inches) in diameter.
What is a broad and flat volcano called?
A shield volcano has a very wide base. It is much flatter on the top than a composite volcano. The lava that creates shield volcanoes is reltively thin. The thin lava spreads out. This builds a large, flat volcano layer by layer.
How many volcanoes erupt at the same time?
In theory, there is no limit on the number of volcanoes that could erupt at once other than the number of active volcanoes themselves: while it is thus theoretically thinkable, that all 600 volcanoes (on land) known to have had eruptions during recorded history erupt at once, this is so unlikely that it can be excluded …
Does the ground shake when a volcano erupts?
This is small but constant shaking possibly caused by the turbulent motion of the magma in the conduit. Typically when volcanologists are watching a volcano that is restless, the onset of harmonic tremor is a good sign that an eruption is likely to occur in minutes to days.
What happens to the ground when a volcano erupts?
On Earth, the lava comes up from the mantle (which is the layer under the surface). Once there’s enough molten rock — called magma — and enough pressure on it, a volcanic eruption occurs. In other places, lava, gases and ash flow out through vents. They can eventually create become cone-shaped hills and mountains.
What happens when lightning strikes lava?
The heat and friction create a differential in electric charge that sparks a strike. The lightning zaps in and out of the thick plumes of rising ash, making the ash so hot it sometimes turns into liquid.
Can a volcano be forced to erupt?
“Humans cannot stop or control an eruption,” Babb writes in an email, “but [humans] have taken some actions to control products erupted from a volcano.” Diverting lava flows, for instance. Babb points to Mount Etna and that 1983 eruption we mentioned earlier, which sent lava flowing into populated areas.
Can a volcano be prevented?
To date there have been no successful efforts to start, stop or reduce a volcanic eruption; however, the ideas exists and discussion is underway. However, if we are able to initiate a volcanic eruption we could schedule the event and prepare, properly evacuate and effectively eliminate risk to human well being.