-
What is a hazard?
A type of threat that hasn't happened yet, but there's potential for some serious damage
-
What is a natural disaster?
- -Causes significant property damage
- -Kills people
- -A natural event that has a negative effect on humans
-
What is a great natural disaster?
- -Effects many people
- -Covers a large area
- -Has a long recovery
- -Requires external assistance
-
-
What is mitigation?
Activities to reduce losses from future disasters, including prevention and protection
-
What are the methods of mitigation?
- Alter-modify the hazard
- Adapt-modify structures
- Avert-redirect the hazard
- Avoid-stay away
-
Who is Alfred Wegener?
He proposed the idea of continental drift and the supercontinent called Pangaea
-
Who is Harry Hess and Robert Dietz?
They proposed mantle convection, seafloor speaking, and lithospheric plates
-
What are some of the evidences that Alfred Wegener used and how do they support plate movement?
- -The fit of the continents
- -Matching geology (location of glaciers, fossils, and rock types)
-
What are some of the modern evidences for plate tectonics and how do they support plate movement?
- -Seafloor spreading
- -Mid ocean ridges
- -Magnetic stripes
- -Trenches
-
What are the layers of the Earth?
- -Inner (solid) and outer core (liquid)
- -Mantle (mesosphere has stiff rocks, asthenosphere is soft plastic, lithosphere is hard like rock)
- -Crust
-
What are the types of plate boundaries?
Convergent, divergent, transform
-
What features do you find at each type of plate boundary? Why?
-Convergent (trenches) plates create volcanoes and earthquakes. Divergent plates are mostly volcanoes. (mid ocean ridges) Transform plates earthquakes
- -Convergent: earthquakes are deep and huge, volcanoes are big and dangerous. Means coming together
- -Divergent: earthquakes are weak and shallow, volcanic activity is mild. Means going away
- -Transform: earthquakes are shallow and intermediate strength, no volcanoes. Means sliding across
-
What happens in subduction zones? AKA convergent plates
-Largest earthquakes, tsunamis, volcanoes
-
What is a hypocenter/focus?
Point where initial rupture occurs beneath the surface of the fault
-
What is an epicenter?
Point on earth's surface directly above focus, usually not on the fault
-
What is a scarp?
Where the fault plane broke the earth's surface, exposed area
-
What are the different fault types?
- -Normal fault: hanging wall moves down(divergent)
- -Reverse/thrust fault: hanging wall moves up (convergent)
- -Strike-slip fault: hanging wall moves laterally(transform)
-
How do you distinguish between a right and left lateral strike-slip?
- -Stand on a fault
- -Look down the fault line
- -What side moved toward you
-
What are the four types of waves? How are they different?
- Body Waves:P waves-parallel and compression called primary, moves 6km/s
- S waves-shear waves, called secondary, moves perpendicular to the wave, travels 3km/s
- Surface WavesLove waves-side to side movement, bad for buildings, most destructive
- Rayleigh waves-rolling surface, moves up and down
-
What is elastic rebound theory?
- The earth builds up energy and nice it is released the earth can't reset
- Ex. Rubber band
-
What are the main factors that contribute to shaking?
L and R waves
-
What does magnitude measure? How is it measured?
- -Richter scale or seismograph
- -Based on wave amplitude and ground displacement
-
What are the differences between Richter and Moment scales?
Richter scales are based on wave amplitude and ground displacement while moment scales are based on rupture dimensions
-
How do we triangulate earthquakes?
Calculates where the earthquake started by looking at 3 points
-
How does liquefaction occur?
- -Related with earthquakes
- -Water ills in the pore space between grains and eliminates all grain to grain contact
- -Whatever is on top will sink
- -Ground behaves like a liquid
- -Things less dense will rise
-
What are the key ingredients to liquefaction?
-
How does tsunamis, fires, and landslides relate to earthquakes?
-Ground shakes and cause land to move, tsunami's because of displace of the seafloor, fires due to breaking of gas pipes
-
What are the factors that affect shaking in earthquakes?
- -Distance to epicenter/fault
- -Depth of focus (hypocenter)
- -Direction of rupture
- -Local geology
-
What are the building types we discussed and how can you identify each of them?
- Unreinforced masonry buildings (old brick buildings)- Brick pattern, narrow windows
- Soft story (garage story)- Built on stilts or a garage
- Modern seismically safe home- Modern homes are up to code
-
What are the three types of volcanic rocks?
- Rhyolite-lighter color cause of iron, more silica Andesite-medium iron and silica
- Basalt-less silica, darker color
-
What is viscosity?
-The resistance to flow
-
What causes high viscosity?
High silica and lower temperatures
-
What causes an explosive volcanic eruption?
Viscous magma and high volatile content
-
Describe a composite volcano
- -High viscosity
- -High volatiles
- -High volume
-
Describe a shield volcano
- -Low viscosity
- -Low volatile
- -Large volume
-
Describe a cinder cone
- -Moderate viscosity
- -Moderate volatile
- -Low volume
-
Describe a lava dome
- -High viscosity
- -Low volatile
- -Low volume
-
What rock features could you get from a spatter cone?
- Low, steep sided hills or mound of welded lava fragments
- -Low viscosity, lots of gas
-
What is ash?
- -Broken up rock
- -It’s like sand and glass
-
What are the signs of an impending eruption?
- -Changes in gas emission
- -Earthquakes
- -Ground bulging
- -temperature increase
-
What are lahars?
Snow melts and ash mixes with it
-
What are pyroclastic flows?
-Big explosion where the ash falls into the air
-
What are fumeroles?
-Toxic gas
-
Describe the case study of Kratkatau
- -1883
- -Loudest sound ever (Heard over 2,000 miles away)
- -Vibrant sunsets
- -Led to Munch painting "The Scream"
- -Global temperature dropped by 2 degrees
- -Shock wave traveled the earth 7 times
-
Describe the case study of Eyjafjallajokull
- -No flights for about a week
- -Cost airlines about $1.7 billion
-
Describe the case study of Pinatubo
-Thousands saved due to forecast
-
Describe the case study of Mt. Tambora
- -Located by a subduction zone
- -Largest eruption in recorded history
- -Caused year without a summer
- -1816
- -Mary Shelley wrote Frankenstein
- -Joseph Smith Senior moves to New York
-
Describe the case study of Versuvius
-Pryroclastic flow was a problem
-
Describe the case study of Rainer
-Lahars was a problem
-
How do you classify a landslide?
What is the rock and how did it move and how fast is it moving
-
What are the classifications of landslides?
- Slides:Slump- slow
- Glide- rapid
- Flow:Avalanche- very fast
- Creep- extremely slow
- Fall:Rockfall-extremely rapid
-
What is the factor of safety and how is it calculated?
- -It is one magic number
- -If it's above 1 then it stays
- -If it moves below one it moves
- -Factor of Safety = Resistance Force/Driving Force
-
What are the factors that contribute to landslides?
- -Dipping beds (rocks that are flat but tilted)
- -Saturated soil
- -Steep slopes
- -Lack of vegetation/rock/soil type
- -Stupidity
-
What are bedding planes?
Ancient fault surfaces which are weakness planes
-
What are daylighted beds?
When the beds are exposed
-
How does water affect the stability of a slope?
- -Water is heavy and adds weight
- -It forces particles apart like air hockey
- -Allows for material to flow
-
What is the role of the angle of repose?
- -It is the angle that the slope can handle before it falls
- -Sand is 35 degrees
-
What is the role of vegetation in slope stability?
- -It holds soil and rocks in place
- -They remove water from the slope
-
What is water infiltration?
- -Watering the grass starts to saturate the slopes
- -Spring gets the most water in the ground due to snow melting
-
What is wave undercutting?
-The waves corrode the base of the cliffs causing them to fall
-
What is frost wedging?
- -A process that occurs in the mountains in the Spring
- -The snow melts and in the day time it expands the rocks causing wedges so the rocks aren't touching anymore and they slide off
-
Describe the function of clay in landslides
- -The enemy
- -Low strength
- -Very slippery
- -Holds moisture
- -Angle of repose is 9-12 degrees
- -Shale is clay compressed
-
What does removing the toe do to a slope?
-Toe resists movement so a landslide happens
-
How can you identify landslides?
- -Hummocky (irregular ground surface)
- -Cracks or terraces (scarps) on hillside
- -Mouth of a canyon
- -Natural springs
-
What are the methods of mitigation for landslides?
- -Inclinometers
- -Drainage control
- -Slope support/anchors
- -Vegetation
- -Geosynthetics
- -Retaining walls
- -Rock fall netting/mesh
- -Debris flow channels
-
What are the things necessary to make a good retaining wall?
- -Has to be super strong
- -has to have drains
-
Describe the case study La Conchita
- -1995 didn't kill anyone
- -2005 killed 10 people
- -Retaining wall didn't hold
- -Filed lawsuit against county
- -15 inches of rain in 15 days
- -Rapid mudflow
-
Describe the case study of Vajont Dam
- -1963
- -Italian government
- -Landslide fell into the dam causing water to rise over the dam
- -800 ft wave
- -2,000 deaths
-
What is base level and why is it important?
- -The lowest elevation to which a river will erode
- -Once it starts reaching base level it will start to meander
-
What is a drainage basin and what is its effect on flooding?
- -All the little rivers that drain into a big river
- -Bigger drainage basin means bigger flooding
-
What happens when a river is constricted? Widened?
- -Narrow stream means faster water and more erosion
- -Wider stream means slower water and more deposition
-
What is discharge?
-Volume of water that flows past a point in a given time
-
What is gradient?
-The slope of the stream channel
-
Describe a meandering stream
- -Happens at base level
- -Have good floodplains
-
What is an oxbow lake?
-Happens when a meandering lake erodes too much
-
Describe a braided stream
- -Happens at bottoms of mountains
- -Shallow
- -Overloaded with sediment
- -Faster water
- -Well defined floodplain
-
Where does erosion occur in lakes?
-On the outside of the bend
-
Where does most of the deposits happen in the river?
-On the inside of the bend
-
What is the outside of the bend called?
Cut bank
-
Describe flash flood
- -Upstream flood
- -In more mountain area with braided stream
- -Large amounts of rainfall over a short period
- -Water gathers in canyons with high amounts of energy
- -Results in alluvial fan by dumping all the sediment at the bottom of the canyon
-
Describe regional flood
- -Downstream flood
- -Meandering stream
- -Lots of rain over a large area that increases water levels and can last for weeks
- -Low topography
-
What is negative feedback?
-When something stops or slows a process
-
What is positive feedback?
-Something that continues the ongoing bad cycle
-
What is avulsion?
-River finds a new course
-
What are levees?
-Barriers to keep the water out
-
Describe the case study Hannibal, Missouri
- -Planned for 30 ft flood, built 31ft levee
- -River rose to 32 ft
- -Water standing in flood plains 30-60 ft deep
-
Describe flood frequency
- -The longer the small chance it will happen
- -1 divided by the number year flood
- Example: 50 = 2%; 500 = 0.2%
-
Describe the case study Yellow River-China's Sorrow
- -It picks up a lot of sediment so it looks yellow
- -High silt conent
- -1887 naturally killed 2,000,000 people
- -Second deadliest natural disaster in history
- -1931 naturally killed about 4,000,000 people
- -Seven cyclones hit in one year
- -Deadliest natural disaster in history
- -1938 Military blows levees to stop Japanese, it didn't work, and they didn't warn their people
- -Killed about 900,000 of their own people
-
Describe the case study of Johnstown, PA
- -1889
- -Two rivers surrounding city
- -Dam failed due to
- -Hunting and fishing club in charge of it, but didn't take care of it
- -Put up mesh net to catch fish but it blocked the spillway
- -Sold drainage pipes
- -Shaved the top of the dam for their carriages
- -Picked up lots of steel and factories burned
- -2,209 people died
- -American Red Cross came about with Clara Barton
-
Describe the case study Big Thompson
- -July 31, 1976
- -Night before 100th year of Colorado statehood
- -Raining in the mountains, not in valleys so people can't see
- -V shaped valley
- -12 to 14 in of rain in 4 hours
- -Flash flood
- -143 deaths
-
Describe the case study Cairo, Illinois
- -Between Mississippi and Ohio river
- -2011 getting ready to flood
- -Blew up levee to lead the flood to the farmers land instead of the city
-
What are the conditions for tornadoes?
- -Collision of air masses
- -High wind shear
- -Intense updraft
-
When is tornado season?
April-July
-
How do you measure tornadoes and what is it based on?
- -Enhanced Fujita Scale
- -Based on wind speed and damage
-
What is wind shear?
- -Wind blowing in different directions
- -Generates tornadoes
-
What lifts things up in a tornado?
-Low pressure
-
What do you do if there is a tornado coming?
- -Get underground
- -Inside first floor bathroom of your house
-
What is the Coriolis effect?
-Atmospheric circulation combined with rotation of Earth
-
Describe low pressure and high pressure
- -Low pressure is severe weather
- -High pressure is cooler temperatures and clear skies
- -Cold front means higher pressure
- -Low pressure and warm front is sever weather
-
What fronts have to meet for a tornado to form?
-Warm and cold
-
What type of air holds more moisture?
Warm air
-
How are severe thunderstorms generated?
-Warm moist air that moves upward, it cools, condenses, and forms cumulonimbus clouds
-
What are supercells?
- -Really big thunderstorms
- -There's an updraft that rotates upward causing a wall cloud which turn into tornadoes
-
What is the crest and wavelength?
- -The crest is the top of the wave
- -Wavelengths are the distance between one crest to another
-
What happens if you have a steep beach?
-You have a plunging breaker (tall waves that surfers go on)
-
What happens when you have gentle slopes?
-It's called a spilling breaker
-
What is wave refraction?
Bending of the wave due to something in the way
-
What is a sea stack, sea arch, and sea cave?
- -A stack of rocks in the sea
- -An arch in the sea
- -A cave in the sea
-
What is a headland?
- -Something that will eventually erode
- -A piece of land sticking out in the ocean
-
What is longshore drift?
-Waves coming at an angle and pushes the sand along the shore
-
What is a spit and how is it created?
-A peninsula of sand caused by longshore drift
-
What are barrier islands?
- -Large supply of sand
- -Due to longshore drift
-
What are groins?
-Rocks that stick perpendicular to a shore (used to build beaches/adds sand)
-
What are breakwaters?
-Parallel to the shore (used to build beaches/sand)
-
What are jetties?
-Basically the same things as groins but they come in pairs and they keep the bays open
-
What are seawalls?
A seawall causes beach erosion by focusing energy a its base on the sand
-
What are the atmospheric layers?
- From bottom to top:
- -Thermosphere
- -Mesopause
- -Mesosphere
- -Stratopause
- -Stratosphere
- -Tropopause
- -Troposphere
- (Change 6 degree per layer)
-
Where does extreme weather happen?
-In the troposphere and lowest part of the stratosphere
-
Describe lightning
- -Visible form of energy transfer
- -Caused by electrical imbalance in cloud
-
What do you do if you see lightning?
- -Go inside
- -Don't use corded phone
- -Get away from trees
- -Stay close to ground and in fetal position
-
When is hurricane season?
June-November with August-October being the worst
-
What are the ingredients for a hurricane?
- -Warm water (at least 80 degree F is fuel)
- -High humidity
- -Low pressure
- -Low wind shear
- -Warm moist air rises and condenses
- -Condensing releases heat
- -Starts to create thunderstorms over the oceans
-
What is the eye, and eye wall of a hurricane?
- The Eye:
- -High pressure
- -Center of it
- -Clear day when eye passes over
- Eye Wall:
- -Low pressure
- -Just to the left of the eye
-
What is the worst quadrant of a hurricane?
Right front
-
What are storm surges?
- -Low pressure of hurricane acts like a plunger, pulling ocean up
- -High winds push the water, stacking it up
-
How do you measure hurricanes and what is it based on?
- Saffif-Simpson Hurriane scale
- Based on wind
-
Describe the case study of hurricane Katrina
- -They predicated it a couple months prior
- -75 miles across from the middle to the East side
- -The "fish bowl" city flooded from being 12 feet under water on both sides to 22 feet
- -85% of people got out
- -80% of New Orleans was flooded
- -Water stayed there for a month
- -Most expensive natural disaster in U.S. history at $125 billion
- -1,600 people died
-
Describe the case study Tri-State Tornado
- -1925
- -3.5 hours
- -217 mile track
- -180 mph winds
- -Over 600 dead
-
What are the conditions for wildfires?
- -Dry conditions
- -Lightning
- -Wind drafts(causes fire to spread)
- -Debris flows after
-
Describe blizzards
- -Snow
- -35 mph wind
- -Visibility less than 0.25
-
What is karst topography?
- -Dissolution of rocks
- -Limestone dissolves easily
-
Describe stalactites and stalagmites
- -On the ceiling
- -On the ground
-
What is a sinkhole?
-A cavern underground
-
What is subsidence?
-Removing water from an area that cause ground to fall/sink
-
What happens to clay when it gets wet?
-It expands and dries as it shrinks
-
Equations I need to know:
- T=D/R (Time equals distance divided by rate)
- Tsunami is
 - Earthquake increase from one magnitude is 32x
-
What is lava?
-Hot molten rock erupted from a volcano
-
What is magma?
-Hot fluid below or within the earth's crust
-
At which tectonic settings would you find the three types of volcanic rocks?
Andesite and Rhyolite at convergent, Basalt at divergent
-
What is intensity and how do you measure it?
-It is the severity of the shaking and is measured with the Modified Mercalli Intensity Scale
|
|
