Volcanoes Flashcards
What is a primary characteristic of volcanic eruptions?
They can occur without warning and vary in intensity.
What may occur before a volcanic eruption?
Gases may be emitted, temperatures may rise, or vibrations may be felt.
What makes predicting a volcanic eruption challenging?
It’s difficult to predict the direction of lava flow, area of influence, and speed of movement.
How do scientists define an ‘active’ volcano?
A volcano showing signs of unrest, like unusual earthquake activity or significant gas emissions.
Define a volcano.
A natural crack in the Earth’s crust that links the surface to the mantle, allowing magma to erupt.
What is the difference between lava and magma?
Lava is molten rock that flows out from a volcano; magma is molten rock beneath the Earth’s surface.
What is a volcanic cone?
A cone-shaped hill formed from the accumulation of volcanic material around a volcano.
True or False: All volcanic eruptions are violent.
False.
Fill in the blank: A volcano can occur on the _______ or under the sea.
seabed
What is one factor that complicates the lifespan prediction of a volcano?
Variability in eruption patterns and signs of activity.
What materials are typically ejected during a volcanic eruption?
Magma and other volcanic materials.
Describe the shape of a composite volcano.
It is typically cone-shaped.
What is a significant feature of volcanic eruptions that may go undetected?
Unusual gas emissions or increased seismic activity.
