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Natty D Final
Natural Disastas Final
82
Geology
Undergraduate 4
05/15/2010

Additional Geology Flashcards

 


 

Cards

Term
What is the Nebular hypothesis?
Definition
- Solar system formation. Nebula: largest gaseous clouds, most likely made of hydrogen (75%0, helium (23%), and every other element (2%)
Term
Formation of Solar System
Definition
1. Contraction of Nebula: gaseous cloud contracting inward due to gravity
2. Flattening and Rotation of the nebula: flying saucer-ish shape; lots of gas in the middle
3. Formation of Planetary Rings: gases start differentiating. Protosun (greatest amount of gas) with rings: lightest is farther out, are very gaseous. Inner rings: metallic and rocky
4. Accretion of Planetary Rings: protoplanet circles around ring and sweeps up material in the ring and forms a planet
Term
Differences between terrestrial and jovian planets?
Definition
- Terrestrial planets: Mercury, Venus, Earth, and Mars
o Small compared to larger Jovian planets; must higher temperature because closer to the sun; rocky and metallic
o Silicon, iron, magnesium, aluminum are common on these planets
- Jovian planets: Jupiter, Saturn, Uranus, Neptune
o Outer planets: gaseous giants, large and cold
o Hydrogen, ammonia, methane are common these planets
Term
What is the composition of the earth's lithosphere?
Definition
The earth’s tectonic plates are composed of 100% lithosphere
Term
Where is oceanic crust created and destroyed?
Definition
- Created: Divergent plate boundaries at mid-oceanic ridges
- Destroyed: Convergent plate boundaries at deep oceanic trenches
Term
What is the composition of the earth’s tectonic plate? What type of volcanism occurs at each?
Definition
1. Divergent boundaries – two plates move away from each one another and causes the creation of the oceanic crust. Coincide with oceanic ridges. Normal (dip slip) faults occur here. Spreading center volcanism occurs here. When hanging wall moves down
2. Convergent Boundaries – two plates move toward one another and destroy the oceanic crust. Coincide with trenches. Reverse and Thrust (dip slip) faults occur here. Subduction zone volcanism. When hanging wall moves up
3. Transform Boundaries – two plates are sliding past one another and on oceanic crust is neither created nor destroyed. Right lateral and left lateral strike slip faults. Intraplate (hotspot) volcanism
Term
Where is the asthenosphere located?
Definition
Located below the lithosphere at depths >100km. it is hot, weak and mobile
Term
How does magma differ from lava?
Definition
- Magma – molten rock located below the Earth’s surface, forms intrusive igneous rocks
- Lava – molten rock expelled from a volcano during an eruption; above the surface, extrusive. Is magma that flows on the earth’s surface
Term
How does basaltic (mafic) magma differ from rhyolitic (felsic) magma?
Definition
- Mafic: Basaltic magma has a low viscocity (resistance to flow) and low explosiveness; 50% silica
- Felsic: Rhyolitic magma has a high viscosity and high explosiveness; 70% silica
Term
What type of magma is more likely to be associated with a Plinian-type eruption?
Definition
- Felsic magma (granite and rhyolite) is more likely to be associated with Plinian-type eruptions because of it is highly explosive and the magma has high viscosity
Term
Shield volcanoes
Definition
100% basalt; lava flow; non-explosive; much bigger than scoria scones. Ascends up gradually, most Hawaiian volcanoes are shield volcanoes
a. Mauna Loa - present, Hawaii
Term
Scoria Scones
Definition
100% basalt tephra; smallest; a little more explosive than shield volcanoes; look like a cinder
a. Ex. Paricutin, Mexico (1943, 1952)
Term
Strato Volcanoes
Definition
Composite cones; tephra and lava with average composition equaling andesite; most dangerous volcano highly exposive because of andesite; several layers including lava and tephra; Plinean; stron upward shape
a. Mt. St. Helen’s (1980)
Term
What impact events (or extinction events) are associated with the Deccan flood basalts?
Definition
Dated back 65 million years and coincides with KT extinction. It is a flood province in India
- Deccan: KT Mass Extinction; flood province in India; ~65 million years ago
- Siberian flood basalts: Perminean extinction
- Tunguska: none, it was an even not an actual impact site, the meteor is said to have exploded 8 km above the earth, shockwave traveled around the world twice, found huge devastation but no impact site
- Chicxulub: impact crate, Yucatan Peninsula, Mexico, name means “tale of the devil”, said to cause extinction of dinosaurs
Term
What are tektites?
Definition
- Tektites are natural glass objects, up to a few cm in size, formed by the impact of larger meteorites on the Earth’s surface, glassy spheres that are formed by impact melting
Term
Define deformation and stress
Definition
- Deformation: the change that a rock body undergoes in volume and/or shape
- Stress: the force that produces deformation
Term
Dip-slip faults
Definition
characterized by vertical movement and one piece of crust is moving up while another is moving down
o Normal – divergent boundary, hanging wall goes down causing tensional stress so the 2 sides are pulling away from each other
o Reverse (thrust) – convergent boundary, hanging wall goes up causing compression stress so 2 sides are moving towards each other (shortening length)
Term
Strike-slip faults (transform)
Definition
occurs when there is horizontal movement back and forth and one piece of crust is sliding over another, occurs when there is shear stress
o Left lateral: looking from 1 side the opposite side moves left
o Right lateral – looking from 1 side, the opposite side moves right
o Example: san andreas fault
o Wherever you have a bend in a strike slip fault you will always have a localized area of either compression or tension
Term
Base Shear
Definition
caused by surface waves (love); when side to side movement, sends the top and bottom of buildings in opposite ways, base collapses underneath building
Term
Resonance
Definition
caused by surface waves (Rayleigh); building is move in sync with the period of the wave-flexible building
Term
Liquefaction
Definition
oose ground material will become more compacted during severe earthquake vibrations. Water is then forced out of the small volume of pore space in the more compacted materials, rising upward to liquefy the upper surface
o Results in the sinking of buildings, lateral flow of the ground, and the development of blow holes
Term
Elastic Rebound
Definition
- Elastic rebound was discovered by studying the San Andreas Fault, as plates shift on opposite sides of a fault, stress builds up in rocks and they slowly deform until their internal strength is exceeded. Then a sudden movement along the fault releases the energy and the rocks rebound back to the original straight lines because plates are in constant motion
Term
Hypocenter vs. Epicenter
Definition
- Hypocenter – source of the earthquake (focus) below surface
- Epicenter – surface directly above the hypocenter
Term
Surface vs. Body waves
Definition
- Surface (L) waves – change in shape – restricted to traveling along the surface of Earth. Travel slowest but cause greatest amount of ground shaking
o Rayleigh: S-shaped; up and down motion (ocean waves in sync)
o Love: side to side motion (faster than Rayleigh)
- Body waves – change in volume – travel through Earth’s interior
o Primary (p) waves – waves of compression, changes in volume, move the fastest
o Secondary (s) waves – changes shape
Term
How many seismograph locations to detect an epicenter?
Definition
- 3 seismograph stations, called triangulation
Term
Know the difference between earthquake intensity and magnitude and how they are measured
Definition
- Intensity – effects of earthquake at any given location
o Scale that measures intensity is the modified mercalli intensity scale which characterizes effect and rates; 1 (low) – 12 (high)
- Magnitude – direct strength of earthquake, an estimate of the relative size or energy released
o Richter scale measures magnitude using P-S interval and amplitude of S-wave
o An increase of 1 magnitude on the Richter scale will result in a 10-fold increase in the amount of ground shaking and 30-fold increase in the amount of energy released
Term
Mass Wasting
Definition
- Down slope movement of material under the influence of gravity
- Adding water to a hillside will increase the weight, lubrication, and loss of cohesion, creating more landslides
Term
Slide (Mass-Wasting)
Definition
requires an intact body and must move down a well defined surface
• Slump: rotational slide on a curve surface
• Glide: transitional slide on a planar surface
Term
Flow (Mass-Wasting)
Definition
body moves internally and doesn’t stay intact (like fluid)
• Mud flow: soil that is completely saturated with water in a semi-arid environment that moves down valleys and mountains at a fast rate
• Earth flow: occur in wet environments and flow down hillsides at a slow rate
Term
Talus
Definition
slope of an embankment wall which is thicker at the bottom than the top to resist the pressure of the earth behind it; results of rock falls, accumulation of rock debris is at the bottom of the slope
Term
Atmospheric Heating
Definition
o Driven by solar radiation
o Equator is hotter because it gets direct sunlight; poles receive indirect sunlight
o Overtime hot air will work its way to the poles and the poles work colder air toward the equator (convection currents)
o Solar radiation proved the energy for wind and all forms of weather in the form of heat energy
o Influences on Atmospheric Heating:
• Continents
• Coriolis effect
Term
The Coriolis Effect
Definition
o Air mass bending of objects to the right in the Northern Hemisphere
o Air mass bending of objects to the left in the Southern Hemisphere
Term
Global Wind Patterns
Definition
o As air rises, it cools and expands and that is conducive to cloud formation and rainy conditions
o Air that is compressed and warm is conducive to clear skies
Term
- Continental polar air
Definition
cold and dry
Term
Continental Tropic air
Definition
hot & dry
Term
Marine Polar Air
Definition
Cold and wet
Term
Marine Tropic Air
Definition
Hot and wet
Term
Dominant direction of air movement across US
Definition
o From west-to-east
o It is controlled by high-speed winds (up to 600km/hr) in the upper atmosphere called the polar jet stream
Term
relationship of global warming to growth of the human population
Definition
- The burning of fossil fuels = increasing greenhouse gases
- Melting polar ice caps = rising sea levels
Term
Low Pressure Systems
Definition
When air rises it cools and expands, it is conducive to cloud formation and rainy conditions that travel across the Northern Hemisphere (better known as mid-latitude cyclones and more loosely known as lows, cyclones or storm systems) typically develop, intensify and dissipate over periods of 3 to 4 days. In the process, they travel thousands of miles, disrupt “normal” life as they go, are responsible for much of the precipitation that falls, and can encompass areas as large as the central US. They are much more common and more intense during the winter season that during the summer season.
o Example: equator, there is constant cloud coverage
Term
High pressure systems
Definition
as air descends it warms and compresses, conducive to clear skies and dry conditions tend to be of two types: either the semi-permanent systems that occupy the central portions of the Pacific and Atlantic Oceans, or the large systems that represent the large domes of cold (cool) air that invade southern latitudes following the passage of lows.
o Example: horse latitude
Term
In what way do regional pressure systems control the global movement of wind?
Definition
- Around low pressure systems, winds flow counter clockwise in the northern hemisphere, clockwise in the southern hemisphere
Term
Thunderstorms (early stage)
Definition
cold front moves under warm air causing the warm air to rise (updrafts), this causes the cloud to build (30,000 ft.); cumulus clouds
Term
Thunderstorms (Mature Stage)
Definition
updrafts + downdrafts, heavy rainfall. Hail formation
Term
Thunderstorms (Dissipating Stage)
Definition
only downdrafts, dry air, clouds dissipate, little rain
Term
Lightning
Definition
form of stratic electricity; shearing forces gives upper part of cloud a positive charge and the lower part a negative charge; generates 50,000 degrees F, (hotter than surface of the sun)
o Lightning within a cloud
o Lightning from cloud to cloud
o Lightning from cloud to ground
• Stream of electrons comes out of cloud “Step Leader”
• Each flux causes more electrons to buildup
• Flux continues until “step Leader” is 50m from ground
• Protons reach up from the ground to connect
Term
Thunder
Definition
must have lightning to have thunder
o Noise
o Heat creates immediate effect of thermal expansion causing sound waves to compression, this occurs at the same time as lightning
o Travels 1mile/5seconds
Term
Hailstorms
Definition
travels up and down the cloud through up and down drafts
o Born out of thunderstorms (do not correlate)
o Need unusually cold air to produce hail within cloud jet stream
o The bigger the hailstone (onion layers) the larger the updrafts were
Term
Tornadoes
Definition
- 70% of all tornadoes occur in North America
- 900 per year in the US
- Season: late spring, early summer
- Fastest winds on the planet
- Must have a thunderstorm to create a tornado
- Average wind: 100-200 mph
- Measured on the Fujita Scale F0 (low) – F5 (high.. 300 mph)
- Lateral speed: 40-65 mph (moves with the cloud, usually in the northeast direction)
- Formation:
o Jet stream will tilt the cloud creating a super cell
o Shearing forces cause the cloud to twirl, creating a vortex (1 km in diameter) that comes out of clouds
o Jet stream sucks air out causing really big drafts
Term
Hurricanes
Definition
- Occurs in a low-pressure systems, beings with a tropical depression where the wind speeds are greater than or equal to 23mph
- As it picks up more speed, turn into a tropical storm, and the wind speeds are greater than or equal to 40mph
- Once wind speeds reach 74 mph or greater, it is considered a hurricane
- The Sapphir-Simpson categorizes the Hurricane from category 1-5
- Hurricanes never form on the equator, but within 5-20 degrees north or south
Term
Hurricane? Cyclone? Typhoon?
Definition
- They’re all the same, given different names at different regions
o Atlantic: hurricane
o Indian: cyclone
o Pacific: typhoon
Term
How does the eye and eye wall of a hurricane differ from the rest of the storm?
Definition
- Eye: the calmest part of the storm, high-pressure
- Eye Wall: the most violent part of the storm; most rain, high winds, low-pressure system
Term
How does a hurricane differ from a tropical storm or a tropical depression?
Definition
- Tropical depression – ~23mph
- Tropical storm - ~40mph
- Hurricane - ~74mph
Term
What is the Storm Surge?
Definition
- Simply water that is pushed toward the shore by the force of the winds swirling around the storm, huge mound that sits directly under hurricane
Term
Where in the US are you more likely to experience thunderstorms? Hail storms? Tornadoes?
Definition
Midwest
Term
How would you determine how far away you are from a thunderstorm?
Definition
1 mile / 5 seconds
Term
What relationship does the jet stream have to the generation of hailstorms and tornadoes?
Definition
Jet streams create tornadoes
Term
In what way does the gradient and overall character of a stream change down slope?
Definition
- Gradient – the slope of a stream, the higher the gradient, the higher the velocity, the steeper the slope
Term
What is a drainage basin?
Definition
Drainage basin – area drained by a stream and its tributaries
Term
What is a divide?
Definition
- An high area that separates one drainage basin from another
Term
Main different Characteristics of an Upland Region Vs. a Lowland region?
Definition
- Upland region – far from base level, high gradient, low discharge, low velocity, and V-shaped valleys
- Lowland region – close to base level, low gradient, high discharge, high velocity, and wide valleys
Term
Fundamental differences between a Lowland flood and an upland flood?
Definition
- Upland flood – local and rapid, death count is usually high, but monetary damage is low. Flash Flood!
- Lowland flood – regional and prolonged, death count is low, but monetary damage is high. They test human endurance more than any other natural disaster. The lag time between rainfall and the peak of flood discharge is greater in lowland floods because it’s longer with more surface area
Term
Mt. Pele
Definition
destroyed the village of St. Pierre by a pyroclastic flow – people couldn’t leave because of election
Term
Mt. Vesuvius
Definition
destroyed Pompei and Herculaneum by pyroclastic flow
Term
Nevado del Ruiz
Definition
destroyed Armeno by Lahar
Term
Paricutin
Definition
the most famous eruption of a scoria cone
Term
Yellowstone
Definition
biggest eruption ever before human time – is a caldera now
Term
Mt. Rainier
Definition
produced lahar
Term
Mauna Loa
Definition
largest volcano on earth, 1 of 5 volcanoes that form the island of Hawaii – shield volano – non-explosive
Term
Lisbon (1775)
Definition
- Intraplate earthquake, 3 earthquakes struck in rapid succession over 2 hrs. 1st was the greatest magnitude 9.0, lasting 6-7 minutes.
- Greatest earthquake in recorded history, 60,000 people killed, tsunami caused 50 ft waves in harbor, and 12 foot waves in the Caribbean’s 3500 miles away
Term
New Madrid (1811-1812)
Definition
- Intraplate earthquake, in Missouri, often of large magnitude, probably occur long zones of weakened crust, recurrence intervals are large (500-800 years)
- 3 great earthquakes occurred over 53 days, 8.5 magnitude, 1500 aftershocks
- Damage covered 7 states, forests were flattened, chimneys damaged, produced a new lake and 2 waterfalls Mississippi river, caused river to reverse its course
Term
San Francisco (1906)
Definition
- Magnitude 8.3, 80% of the damage was caused by fires, water/gas lines ruptured. 3 days, burned 520 blocks.
- Ham and eggs fire was started by a housewife making breakfast without realizing her chimney had fallen away
- 700 deaths, 5000 deaths in the ensuing months due to diseases
Term
Alaska (1964)
Definition
- Anchorage, most violent earthquake in North America, magnitude 9.2
- Lasted 3-4 minutes, killed 131, 24 aftershocks
- Most extensive amount of crustal deformation recorded
Term
Haicheng (1975)
Definition
- First accurately predicted earthquake over a short time
- Magnitude of 7.6 destroyed 90% of city’s dwellings
Term
Tangshen (1976)
Definition
same area as Haicheng
- China. 250,000 people died, was not predicted because nothing unusual happened, 8 magnitude
Term
Loma Prieta (1989)
Definition
- Magnitude 7.1 in Santa Cruz Mountains, occurred along a 40km long segment of the san andreas fault
- 12,000 people displaced, 3500 injuries, 67 deaths, $7 billion property damages
- Nimitz freeway, Bay Bridge, Marina District were sites particulary damaged
Term
Landers / Big Bear (1992)
Definition
- 7.5 magnitude occurred on 3 faults trending: the Camp Rock, Emerson, and Johnson Valley faults
- large big bear quake, along a NE-trending fault, forming a lambda shape with San Andreas Fault, over time, might evolve into the main fault accommodating R-lateral movement b/w the pacific and north American plates
- 1 death, 400 injuries, 750 people homeless, 2 fatal heart attacks
Term
Northridge (1994)
Definition
- Magnitude 6.7, shook for 40 seconds, 61 people killed, thousands injured, 9 freeways, thousands of homes/buildings destroyed, damaged of $20-30 billion
- Northridge fault was unknown, fault planes hidden under surface
Term
Gros Ventre, Wyoming (1925-27)
Definition
- Rock glide involving sedimentary layers inclined towards a valley, permeable sandstone above impermeable clay layers, Gros Ventre River was being undercut at the base of the slope exposing the potential slide plane
- Slide dammed the river and formed a lake behind it, 2 years until the dam was breached by rising waters
- Wave of 15-ft water rush down river gorge and swept through the floodplain where Kelly had stood, only 7 drowned
Term
Vaiont Dam Disaster (1963)
Definition
- Alps of northern Italy, debris slide moved rapidly down slope into a reservoir behind the vaiont dam. Impact created a wave, overflowing dam by 100 m, and was still 70 m high downstream
- Killed 3000 people downstream. Caused by rocks dipping in the same direction as the glacial valley, rocks were composed of highly fractured limestone w/ numerous interbedded clay beds, heavy rains occurred two weeks before slide, adding lubrication.
Term
Yungay, Peru (1970)
Definition
- Earthquake hit high Peruvain Andes. Tore loose a huge block of snow, ice and rock setting in motion century’s worst landslides
- Involved 1000 m free fall of huge block of snow, ice and rock, smashing into ground, generating a gigantic debris avalanche. Hits peeds of 320 kph
- Killed over 25,000 died in about 4 minutes.
Term
Tri-State Tornado (1925)
Definition
- Heard before it was seen, headed toward school in Illinois, killed many schools and teachers, went down railroad track but the train survived by going high speed straight at it, 689 people died, had a mile wide impact path.
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