distribution and prediction of volcanos Flashcards
what are the characteristics of a
composite volcano
Tall
Explosive
Less frequent eruptions
what are the characteristics of a shield
volcano
flat
slow flowing lava
more frequent eruptions
where do most volcanoes occur
on plate boundaries
over hot spots
What is the Volcanic Explosivity Index (VEI)?
A relative measure of the explosiveness of volcanic eruptions.
What factors determine a volcano’s VEI value?
The volume of material ejected, eruption cloud height, and qualitative observations.
Is the VEI scale limited?
No, it is open-ended, but the largest eruptions in history have a magnitude of 8.
What VEI value is given to non-explosive eruptions?
0, for eruptions ejecting less than 10,000 m³ of volcanic material.
What does a VEI 8 eruption represent?
An eruption ejecting 240 cubic miles of material with a cloud column over 20 km high.
How do volcanoes vary in size?
From small cinder cones a few hundred feet tall to massive mountains.
Do all volcanoes have the same shape?
No, some have perfect conical shapes, while others are more irregular.
How long can volcanic eruptions last?
Some erupt once for a few days, while others remain active for millions of years (e.g., Iceland).
What are the key characteristics that define a volcano type?
Eruption type
Eruption style
Eruption period
Rock type
Volcanic features
What factors influence a volcano’s eruption dynamics?
Magma chemistry, gas content, lava flow properties, and eruption rate.
What are the two most well-known types of volcanoes?
Composite volcanoes and shield volcanoes.
