Shared Flashcard Set

Details

Natural Disasters- Exam 2 (Baker-Treloar)
Earthquakes, Earthquake events, Volcanoes,
112
Environmental Studies
Undergraduate 2
04/06/2010

Additional Environmental Studies Flashcards

 


 

Cards

Term
Mt. Rainier
Definition
- Subduction in ROF
- Cascades
- potentially most dangerous in Cascades
- lahar will seriously damage
Term
Mt. St. Helens, 1980
Definition
- Subduction in ROF
- Cascades
- Large Landslides,lateral blasts,lahar and pyroclastic flows
- Most active in Cascades
Term
What are volcanic rocks classified as?
Definition
Igneous Rocks
Term
What are three types of volcanic rocks?
Definition
Andesite, Rhyolite, Basalt
Term
What type of tectonic setting do you find Andesite and Rhyolite Rocks?
Definition
Subduction Zones
Term
What type of tectonic setting do you find Basalt Rocks?
Definition
Mid Ocean Ridges and Hot Spots
Term
Basalt
Definition
-Dark color
-Low viscosity (flows easily)
-Quiet eruption
-Composition of ocean's crust
-Erupts Divergent plate boundaries (MORs) and Hot spots
Term
What are the two most common elements in the crust?
Definition
Silicon and Oxygen
Term
Which 2 elements are always found in minerals that make up volcanic rocks?
Definition
Silicon and Oxygen
*They control the viscosity
Term
Shield Volcanoes
Definition
- large volcanoes with broad, gentle slopes built by basalt flows
- Hot spot volcanoes
Term
Iceland, 1783
Definition
-Greatest lava eruption of historic times
-large basalt flow
-divergent plate boundary
-Laki fissure erupts for 8 months
Term
Iceland, 1973
Definition
-Most recent large basalt flow
-Nearly closed harbor at Heimaey
-divergent plate boundary
Term
Kilauea
Definition
-Most active volcano in the world
-Hot spot
-In the Ring of Fire
Term
What are the 2 types of Basalt flows?
Definition
Pahoehoe and aa
Term
Pahoehoe flow
Definition
Lava cools to form smooth,ropy texture
Term
aa flow
Definition
Lava cools to form rough, blocky texture
(sharp, no flip-flops)
Term
Lava Tube
Definition
-Tunnels beneath the surface of cooled basalt
-Inactive tubes
Term
What are the major gasses emitted from volcanoes?
Definition
-Water Vapor (50 %)
-Carbon Dioxide (CO2)
-Sulfur Dioxide (SO2)
Term
Which gas is responsible for global cooling?
Definition
Sulfur Dioxide
(Blocks some of the Sun before it heats up the Earth)
Term
Which gas is responsible for global cooling?
Definition
Carbon Dioxide
Term
Andesite and Rhyolite
Definition
-Gray-green-brown color
-High viscosity (doesn't flow easily)
-Explosive
-most common in Subduction zones (convergent plate boundaries) and Ring of Fire volcanoes
Term
Pyroclastics or "tephra"
Definition
-"Fire Fragments"
- More common with viscous magma (AKA andesite/rhyolite)
- Ejects fragments of ash, pumice, bombs, and blocks
Term
Eruption Column
Definition
-the mass of ash and gases forcefully blown up from a volcanic vent during an eruption
-cylindrical
-typical style of subduction zone voclanoes
Term
Plinian Eruption
Definition
-tall and large eruption column (approximately 30 miles)
- Examples: Vesuvius and Mt. St Helens, 1980
Term
Composite Volcano or "stratovolcano"
Definition
-Volcano made up of alternating layers of pyroclastics and lavaflows
- Most common in Subduction Zones and Ring of Fire
-Explosive eruptions
- Ex: West Pacific, Alaska
Term
Caldera
Definition
- A large depression in the summit of a volcano
- formed by collapse into underlying magma chamber
- usually more than 1 km across
- Ex: Mt. Pinatubo Caldera, Phillipines 1991
Term
Crater
Definition
- depression on the summit of a volcano
- less than 1 km
Term
Lava Dome
Definition
- Viscous lava solidifies in caldera or crater of a composite volcano
- Acts as a "plug"
-Ex: Mt. St Helens, 1980
Term
What is the difference between a shield volcano and a composite volcano?
Definition
Sheild Volcanoes: Fluid Basalt flowss
Composite Volcanoes: pyroclastics and lava flows (andesite, rhyolite)
Term
Pyroclastic Flows
Definition
- Mixture of hot rock fragments and gasses that pours at a high velocity down the flank of a volcano
- Dry flow
- Occurs in composite volcanoes (andesite and rhyolite)
- Moves at high speeds (100 - 200 mph)
- Occurs at convergent plate boundaries (subduction zones)
-Initiated by dome eruption or collapse
-Very destructive
-Ex: Soufriere Hills, Montserrat, 1997;
Term
Lahar
Definition
- Volcanic mudflow
- Follow large pyroclastic eruptions
- Rapidly flowing mixture of pyroclastics and water
- Originate from the melting of ice, rainfall, or the breakout of a lake
- Ex: Mt. St Helens 1980
Term
Pyroclastic Flow Eruptions
Definition
- Mt. Vesuvius, 79 AD
- Mt. Pelee on Martinique, 1902
- Mt. St Helens, 1980
-Mt. Pinataubo,Phillipines, 1991
Term
Lahar Events
Definition
- Nevado Del Ruiz, 1985
- Mt. Pinatubo, 1991
- Mt. St Helens
- Possibly Mt. Rainer
Term
What are the three ways to melt rock?
Definition
- Increase temperature
- Decrease pressure
- Add water
Term
Mt. Mazazma/Crater Lake
Definition
- Subduction zone in ROF
- Cascades
- Mt. Mazama collapsed to produce Crater Lake
- 42 x larger eruption then St. Helens
Term
Mt. Shasta
Definition
- Subduction Zone in ROF
- Cascades
- Erupted 3 times in last 30 years
Term
El Popo
Definition
- Subduction in ROF
- Mexico
- Danger to Mexico City
- 20 million people live close enough to be affected
Term
Nevada del Ruiz,Columbia South America, 1985
Definition
- Subduction in ROF
- Columbia/ South America
- City destroyed by lahar, evacuation called off
- new respect for fire and ice combination (deadly!)
Term
Krakatau, 1883
Definition
- Subduction in ROF
- Indian Ocean/ Indonesia
- generated 120 ft tsunami
Term
Tombora, 1815
Definition
- Subduction in ROF
- Indonesia
- largest eruption in historic time
- began global cooling, 1816- "year without a summer"
Term
Mt. Pinatubo, 1991
Definition
- Subduction in ROF
- Phillipines
- Plinian eruption
- Caused global cooling
- Pyroclastic flow
Term
Mt. Pelee, 1902
Definition
- Subduction OUTSIDE the ROF
- Martinique, Caribbean
- Pyroclastic flow destroyed town
- Only 1 survivor
Term
Soufriere Hills
Definition
- Subduction OUTSIDE the ROF
- Montserrat, Caribbean
- Most active volcano in Caribbean and anywhere
- Pyroclastic flows (forced evacuation of southern half of island and destroyed capital of Plymouth)
- Possibly next Krakatau
Term
Mt. Vesuvius, 79 AD
Definition
- Subduction OUTSIDE of ROF
- Italy, Mediterranean
- Pyroclastics flow
- Ash fall
- Buried Pompeii
Term
Long Valley Caldera
Definition
- No subduction or Hot Spot
- Calif, Sierra Nevada
- Soon-to-be huge eruption
Term
Yellowstone Caldera
Definition
- Hot Spot
- US
- Most debris from an eruption ever
- Obliterated mountain range
- Magma chamber is building
Term
Focus
Definition
Origin of earthquake or area of fault rupture, most are shallow, weak region in the fault
Term
What are some precursors to volcanic eruptions?
Definition
- Earthquake activity that steadily increase
- Volcano will swell
- Gas will be emitted
Term
Epicenter
Definition
Surface directly above focus, not always on fault
Term
Stress
Definition
Force applied (compressional, tensional, shear)
Term
Stress
Definition
Force applied (compressional, tensional, shear)
Term
Strain
Definition
Change due to stress (deformation in rocks)
Term
Elastic Rebound Theory
Definition
Explains how rocks respond to stress, why earthquakes occur
Term
Triangulation
Definition
Means of locating the epicenter, P and S wave time delay, needs to be 3 sources of data
Term
Paleoseismology
Definition
The study of historic earthquakes
Term
Seismic Tomography
Definition
3-D image of earth’s interior using P wave velocities because they go through liquids and solids
Term
Seismic Gap
Definition
Lack in seismic activity in an area along a fault or a subduction zone
Term
Resonance
Definition
Amplifying effect produced when the natural vibration frequency of ground or structure is matched by the frequency of seismic waves
Term
Liquefaction
Definition
Wet sand or oil can become liquid-like when strongly shaken
Term
Fault creep
Definition
Term
Ground displacement, Offset, Slip
Definition
- Fences and cracks that are moved during an earthquake
- Ground moves from earthquakes
Term
Chile, 1960
Definition
- Tsunami event
- 9.5 subduction zone earthquake
- Largest earthquake recorded
- Tsunami traveled to Hawaii and Japan
Term
Alaska, 1964
Definition
- Tsunami event
- 9.2 subduction earthquake
- Largest US earthquake
- Tsunami wave traveled to Northern CA
- Extensive ground rupture
- landslides
vi) liquefaction
Term
Cascadia Subduction Zone
Definition
- Tsunami event
- Has the potential to generate a magnitude 8 to 9 earthquake
- Happened 300 years ago
- Subduction event with major tsunami
Term
Indian Ocean, 2004 (Sumatra, Indonesia)
Definition
- Tsunami event
- 9.2 subduction mega thrust earthquake
- Tsunami generated
- Seismic gap
Indonesi
Term
What are other possible Tsunami events that could occur in the Pacific Ocean and Atlantic Ocean?
Definition
- Submarine landslides could cause a tsumani (Hilnia Slump in Hawaii, Big Island)
- Landslides around canary Island- Mega tsumani, volcano could cause 300 ft wave to Europe
Term
Turkey (Izmit), 1999
Definition
- Earthquake event
- Continental Transform plate boundary
- Main hazard: structural damage and tsunami
- 7.4 magnitude
Term
Haiti, 2010
Definition
i) Transform plate boundary
ii) Collapse of structures is main cause of death
iii) Fifth most deadly earthquake of that magnitude
iv) rupture search reveals no recent break in probable scarp
Term
San Fransisco, 1906
Definition
i) Magnitude 7.1
ii) Ground rupture was 265 miles long
iii) Extensive fires
iv) Epicenter was on the SAF
Term
Loma Prieta, 1989
Definition
- Mag 7.1
- event in the bay area
- liquefaction and fire
- epicenter on SAF in mountains
- great earthquake
- Last large earthquake
Term
Northridge, 1994
Definition
- Occurred on a blind thrust fault, NOT SAF
- Not on Plate Boundary
Term
New Madrid, 1811,1812
Definition
- In the middle of US
- 8.0 mag
- Great earthquake
Term
China, 1975
Definition
(1) Was predicted
(2) Evacuation was made
(3) 7.3 Earthquake
Term
Tangshan, China, 1976
Definition
(1) 7.6 magnitude
(2) Not on a plate boundary
(3) 93 percent of all homes destroyed
Term
Alaska, 1964
Definition
i) 9.2 subduction earthquake
ii) Largest US earthquake
iii) Tsunami wave traveled to Northern CA
iv) Extensive ground rupture
v) landslides
vi) liquefaction
vii) subduction event with major tsunami
viii) Ring of fire
Term
Mexico City, 1985
Definition
i) Subduction event
ii) In Ring of Fire
iii) 250 miles from epicenter
iv) Town built on ancient lake bed which amplified the seismic waves
v) Collapsed buildings due to resonance
vi) Not on a plate boundary
Term
Chili, 1960
Definition
i) Ring of fire
ii) 9.5 subduction zone earthquake
iii) Largest earthquake recorded
iv) Tsunami traveled to Hawaii and japan
v) Subduction events with major tsunami
Term
Tokyo, Japan, 1923
Definition
i) Subduction event
ii) In Ring of Fire
iii) Fire was worst hazard
Term
Kobe, Japan, 1995
Definition
i) Subduction event
ii) In Ring of Fire
iii) Most recent devastating earthquake in japan
iv) Liquefaction
v) Fire
vi) Most expensive natural disaster yet
Term
Indonesia, 2004
Definition
i) Subduction event with major tsunami
ii) Ring of fire
iii) Megathrust earthquake
Term
Iran
Definition
i) Continent- Continent Convergent plate boundary
ii) Bam Iran- 90 percent of building destroyed because adobe structures
iii) Has had many devastating earthquakes
Term
Pakistan, 2005
Definition
i) Continent-Continent Convergent plate boundary
ii) Massive deaths and destruction
iii) Almost entire towns had vanished
iv) 7.6 magnitude
Term
Sichuan, China, 2008
Definition
7.9
occured on reverse fault
- not on plate boundary
landlside
Term
What are the 2 types of body waves?
Definition
P waves and S waves
Term
P waves
Definition
- Primary Waves- compressional waves
- Felt first, fastest, in a push-pull manner (like a slinky)
Term
S Waves
Definition
- Secondary Waves, shear waves
- Move in a up and down motion
- Does not travel threw fluid
Term
Long L waves
Definition
c) Long L waves
i) Travel near surface after P and S waves strike
ii) Slower then body wave
iii) Low frequency waves
iv) Cause most of the damage
v) Love waves- side to side motion, don’t travel through water
vi) Rayleigh waves- rolling waves, vertical and horizontal shaking
Term
How do P and S waves help us understand Earth’s internal structure?
Definition
- Show the travel path and velocities which can be analyzed to show earths inner structure
Term
Magnitude
Definition
- measure of energy released during an earthquake
Term
Richter Magnitude
Definition
- Ml, measures largest amplitude on seismogram
- Logarithmic scale (5 is 10x stronger then a 4 and 100x stringer than a 3)
- Ground shaking is 10 times worse for each unit on a scale
Term
Moment Magnitude scales (Mw)
Definition
Newer scale, more reliable for large magnitude earthquake
(2) Measures strength of rock, rupture area along fault plane or subduction zone, displacement, slip, or offset along a fault
Term
Modified Mercalli Scale
Definition
1) measures intensity of ground shaking
(2) measure of the effects of an earthquake on humans, structures for the land itself
Term
Where does the San Andreas Fault (SAF) start and end?
Definition
- From Cape Mendocino to Gulf of CA
Term
The SAF is what type of fault?
Definition
- Right lateral strike slip fault.
Term
What plates are on either side of the SAF?
Definition
- North American Plate and Pacific Plate
Term
How fast are these plates moving past each other (cm/yr)? (SAF)
Definition
- 5 cm/yr
Term
What type of plate boundary was CA before the SAF?
Definition
- California was a subduction plate boundary from ~ 150 million to 28 to 24 million years, evolved into a transform plate boundary
Term
What is the name of the other major fault (east of the SAF) in the Bay area?
Definition
- Hayward Fault
Term
Is the probability for an earthquake along the SAF the same everywhere?
Definition
- No
Term
What was emphasized about Parkfield?
Definition
a) Earthquake capital of the world, 90 percent chance there will be an earthquake there
b) the most comprehensively instrumented section of a fault anywhere in the world.
Term
Where was the last great earthquake on the SAF?
Definition
- Mojave segment when it ruptured- 1857, 8.2
Term
Which of the 3 southern segments mentioned below ruptured during this great earthquake event?
Definition
- Mojave Segment, San BErnadino Segment, and Coachella Statement
Term
Creeping Section
Definition
i) santacruz to Parkfield (between LA and SF)
ii) Continuous motion
iii) strain released
iv) earthquakes never about 6.0
Term
"Locked"
Definition
- Sesimic Gap
Term
What is the concern about LA and the Coachella segment?
Definition
b) Energy will propagate north and bounce off the San Gabriel Mountains and straight into downtown LA
c) Coachella Evaluation- It’s been longer since there has been an earthquake, and energy will affect LA
Term
"Big Bend"
Definition
left bend in SAF northeast of LA and Santa Barbara regions causes shear stress to turn into compressional stress
b) Compressive stress causes:
i) Secondary faults:
ii) thrust and reverse faults
iii) Mountains
Term
What fault is a threat to Downtown LA?
Definition
- Puente Hills fault
Term
Where is the Rose Canyon Fault, Elsinore Fault, San Jacinto Fault, and SAF?
Definition
Southern CA
Term
Order of Faults from East to West
Definition
Rose Canyon Fault, Elsinore Fault, San Jacinto Fault, and SAF
Term
Where are the Mojave, San BErnadino,and Coachella valley segments along the SAF?
Definition
Southern CA
Term
Mojave desert
Definition
NOT next to fault
Term
New Madrid Fault Zone
Definition
Central US
failed anicent rift
not on plate boundary
Supporting users have an ad free experience!