Week 5, Chpt 3, 4 Flashcards
(26 cards)
Directivity
Earthquake acting like lasers.
As a rupture moves along a fault line, seismic waves radiating from the rupture can bunch together to create a concentrated pulse of energy.
What can really hard shaking be due to?
Difference in the ground or directivity.
Precursors to Earthquakes
Clustered foreshocks
Crustal strain
Level changes in wells
Gases in wells
Eruption style depends on
Viscosity
Volatiles
Volumes
Our atmosphere is convective as long as
temperature gets lower with altitude.
Scoria
Bigger blocks that are a result of volcanic eruption. These are found closer to the vent.
A cloud of hot gas with rock particles in it. It flows down the volcano travelling faster than 100km/hour and 700 degrees Celsius.
Pyroclastic Flow
What is the process that drives volcanoes?
The Earth’s efforts to release heat.
Element
A pure substance that cannot be separated into other materials.
The smallest part of the element that retains the characteristics of the element.
Atom
Molecule
2 or more atoms bonded together.
A pure substance that can be subdivided into 2 or more elements.
Compound
Mineral
A naturally occurring solid, formed by geological processes.
Has a crystalline structure and a definable chemical composition.
Inorganic.
5 ways to form new mineral crystals
Solidification of a melt Percipitation from a solution Solid-state diffusion Biomineralization Percipitation from gas
Characteristics of minerals
color streak luster crystal shape hardness specific gravity cleavage magnetism reaction with acid
Mineral classes
silicates oxides sulfides sulfates halides carbonates native metals
Extrusive igneous rock
Rock that forms by freezing lava above ground.
Melting Conditions
Decompression melting
Flux melting
Heat transfer melting
Factors that control the cooling time of magma that freezes below the surface in the intrusive realm
Depth of intrusion
Shape and size of magma body
Presence of circulating groundwater.
Molten rock extrudes as
lava flows or pyroclastic debris.
Textures of igneous rock
Glassy, fine-grained, coarse grained.
Magma comes to the surface because
it’s buoyant.
Lahar
Volcanic ash mudflows.
Caldera
When large volumes of magma are erupted over a short period of time, structural support for the crust above the magma are lost. This creates a cauldron like depression.
