Vocab
A long tube through which magma moves from the magma chamber to the Earth’s surface.
Pipe
What is an earthquake’s magnitude?
The amount of energy released by an earthquake
What is a volcano?
A crack in the Earth's crust where magma can reach the surface
What are the three main types of volcanoes?
Shield Volcanoes
Cinder Cone Volcanoes
Composite Volcanoes
What is geothermal activity?
Underground water being heated by magma
A string of islands formed by the volcanoes along a deep-ocean trench.
Island Arc
How does energy from an earthquake reach the Earth’s surface?
Through seismic waves
Where are most volcanoes found?
Ring of Fire/Plate boundaries
What are the two main kinds of volcanic eruptions?
Quiet
Explosive
What are two examples of geothermal activity?
Hot Springs
Geysers
The large hole at the top of a volcano formed when the roof of a volcano’s magma chamber collapses.
Caldera
Where does an earthquake start?
at the focus
What is a hot spot and where do they occur?
An area where the magma from the mantle grows so hot it melts through the crust, usually in the middle of a plate
Active - currently erupting volcano
Dormant - not currently erupting but may in the future
Extinct - not erupting and most likely will never erupt again
How does a volcanic neck form? What is the difference between volcanic sills and volcanic dikes?
Magma cools and hardens inside the pipe of a volcano
Sills squeeze in between rock layers, dikes moves across rock layers
A deposit of hardened magma in a volcano’s pipe.
Volcanic Neck
Describe the kinds of movement produced by each kind of seismic wave.
P Wave - squeezes and expands the ground
S Wave - moves the ground side to side and up and down
Surface Wave - shakes the surface side to side and makes it roll (like ocean waves)
How do hot spots form island arcs?
The plate moves across the hot spot, with land being created as the plate moves over it
Describe the process of how magma reaches the surface through a volcano.
Magma fills the magma chamber, gas pressure increases and forces it up the pipe, reaches the vents and spills onto the surface
What two landforms, that are not volcanoes, form from lava and ash?
Lava plateaus
Calderas
A slab of volcanic rock formed when magma squeezes between layers of rock.
Volcanic Sill
Name and describe the three ways we can measure earthquakes.
Mercalli Scale - damage at a certain location
Richter Scale - measuring the seismic waves
Moment Magnitude Scale - estimates the total amount of energy released by an earthquake
What are the two types of plate boundaries where volcanoes can form?
Converging
Diverging
Compare how the three main types of volcanoes are created.
Shield - lava flowing and hardening over itself from quiet eruptions
Cinder Cone - explosive eruptions with pyroclastic flows
Composite - alternating quiet and explosive eruptions
What kinds of landforms form from magma?
Volcanic Necks
Volcanic Sills
Volcanic Dikes
Batholiths