Chapter 25.3 & 25.4 Flashcards
What is the boundary that marks a density change between layers?
Discontinuity
How are discontinuities identified?
By using seismic waves
What are shadow zones?
Areas where seismic waves aren’t recorded
What is another name/term for “Shadow Zone”?
Dead zone
Between which degree range do “Shadow Zones” fall?
105-140 degrees
Is the Outer Core a liquid or a solid?
Liquid
Is the Inner Core a liquid or a solid? Why?
Solid, because of the pressure
What makes up the Lithosphere?
Crust and uppermost mantle
What is the Asthenosphere?
A plastic-like layer on which Earth’s plates move.
Which elements make up the mantle?
Calcium, Aluminum, Iron, and Magnesium
Which elements make up the Core?
Iron and Nickel
The measure of a fluid’s resistance to flow
Viscosity
The chemical compound silicon dioxide, SiO2, which is a common ingredient in most magma
Silica
Volcanoes that tend to be small, have heights in the hundreds of meters range, and have short eruption cycles
Cinder cone volcanoes
Broad, flat structures composed of layer upon layer of lava flows
Shield Volcanoes
Volcanoes that are large and steep-sided, often thousands of meters high and tens of kilometers across the base, and composed of layers of both lava and ash
Composite volcanoes
What is molten, or liquid rock, stored inside Earth called?
Magma
Where is the Ring of Fire located?
On the Pacific Ocean shoreline
Which two specific locations, have volcanic activity, due to divergence?
East African Rift Valley and Mid-Atlantic Ridge
Are hot spots stationary?
Yes
What can hot spots create?
Islands (Hawaiian Islands)
If the viscosity is higher, will the fluid flow more quickly or slowly?
More slowly
If magma has a high viscosity, will it contain more or less silica?
More silica
What is Pyroclastic Material?
Any solid material that erupts from a volcano
What is the smallest Pyroclastic Material?
Volcanic Ash
What is the largest Pyroclastic Material
Volcanic blocks and bombs
What types of gases erupt from a volcano?
Water Vapor, Carbon Dioxide, and Sulfur Dioxide
What is the eruptive style linked to?
Temperature and composition
How are volcanoes classified?
According to their size, shape, and the materials that erupt
What are the three types of volcanoes?
Shield, Cinder Cone, and Composite
