Natural Disasters

Earth proces that, upon interaction with human activity, causes loss of life and property

• without it there would be no hazard
• because of it, science of geohazards become more important every year

• more people living in hazard prone areas (disasters are becoming more frequent and since population is growing, more people move to marginal lands)
• populations becoming hyper-concentrated
• consumption of resources
• 50% of the population lives in cities -> increase to 70%

Yuriage, Natori

• geologic processes
• population growth
• can't lessen disasters

• must try to mitigate hazards
• changes in engineering practices (buildings)
• aducating people
• management plans

• Volcanoes, floods, earthquakes, storms, landslides, tsunamis, hurricanes, meteorites
• can ccur ith or without warning
• precoursers can occur

• Frequency vs. magnitude
• F: How oftern a given event occurs in a certain region
• M: how powerful (amount of energy released)
• Scope: area affected by a given hazard
• local
• regional
• global

Seismic energy is usually caused by brittle faults

• magnitude 7.7 - 8.3
• epicenter 2 miles offshore of San Francisco
• Huge fires

Magnitude of 7.0

• kills the highest number of people per year
• strike without warning
• no time for evacuation
• not a predictable trend to earthquake numbers, magnitude or location

• Reinforce buildings
• education
• disaster plan -> minimize casualties

Sumatra - earthquake occured at a convergent boundary

• Biggest earthquake in Japan in 1,200 years
• magnitude 9.0
• 33 ft high waves
• five continuous minutes of shaking

• monitoring
• building restrictions in hazard prone areas (hilo harbor and downt)
• Seawall construction
• cause early wave breaking
• prevent wave run up into urban areas
• Education
• warning
• evacuation
• general understanding (run to high ground)

• Bangladesh -> Gorgi
• Most widespread destructive weather hazard
• Saffir Simpson Hurricane Scale categories (1-5)

most costly and most deadly in US history

• storm surge
• wind
• -loss of power
• flying debris

• Monitoring
• Infrastructure (place for evacuation)
• Education and planning

• earth concentrates energy
• release energy violently

• 115BA
• The big bang thoery -> compressed matter which exploded and has been expanding in the universe ever since
• expanding and shifting towards the red end of the spectrum (red shift)
• Explosion/ Contraction
• Contraction -> when the light shifts to the blu/ violent of the of spectrum

• World is in this galaxy (3/5 out in one of the arms)
• Spiral Shape
• Two arms
• 100 thousand years across (240 billion stars)
• Flattened disc and central bulge

• Pluto -> to small and orbit is different (NOT part of the system)
• We are in a second generation star
• Saturn, Jupiter, Earth, Moon, Mercuy, Venus, mars, Uranus, Neptune
• Gravity -> the attraction between objects
• Earth 3rd planet out

• Showing (growing of the planets -> caused by gravity)
• (a) the formation of planetesimals from the dust of the solar nebula and
• (b) the formation of planets through the impacting and accretion of planetesimals

• Average terrestrial planet (mercury, venus, earth)
• Jovian planets (accumulation of gas)
• Free water -> only planet that has a vast amount
• Plate tectonics -> inside of planet is hot -> outside is cold
• Three types of rocks

• gravity pulls the heaviest to the center -> created the core iron/nickle
• planetary differentiation
• core/ mantel (liquid causes plate tectonics) / crust
• layering out of earth due to gravity by density
• Lightest outgassed from volcanoes

• Sedimentary
• Metamorphic
• Igneous

• Exogenic Cycle -> gets energy from the sun
• Heat to evapurate
• rivers/ flooding

• impact of asteroids during planetary accretion
• decay of radiocative elements -> Heat
• gravitational contraction -. friction between monucules -> Heat

• Gravity
• Every particle attract other particles
• g = a X b -> gravity is proportional to the mass of the two particles
• g= 1/d^2 gravity is inversly proportional to the squared distance of the two objects
• Sun affects less because its father from the earth compared to the moon
• g = Gab/d^2
• *G = universal gravitational constaant
• This force holds the universe, solar system, EVRYTHING together but it can also tare things apart

Atom -> Molecule -> Mineral -> Rock

• atoms fill outer shell with electrons e-
• BONDING -> atom donates to another atom its electron
• (ionic/ covelant) Ionic bonding
• Covalent Bonding
• form by sharing electrons
• Bodning creates minerals

• Solid (ice)
• Naturally occuring
• Homogenous -> minerals the same throughout
• Inorganic
• Specific chemical composition
• Specific structural arrangement (crystal/pattern)

• 1915 Alfred Wegener - Pangea
• Theory of continental drift and developed lines of evidence to his theory
• Theory failed because he did not provide a mechanism

It looks like the continents fit together

Animals interbreed before the continents separated

• Igneous needs a common source
• Metamorphic

• Sedimentary rock
• Mirrors climate across the world
• tropical regions (coral reefs)
• Deserts 30 degrees above and below the equator
• water sorted based on the size of the sediments

• Wegner failed to provide a physical mechanism, to explain the movement of huge boulders to other areas
• Wegner finds a mechanism - the gravitational pull of the moon towards earth moved the boulders

Old magnetism: there are stripes on the sea floor that goes from normal to reveerse polarity as you go across the ocean

• Magnetic field S -> N (reverse polarities)

Sediment is laying in order from oldest to the newest

There is a volcanic chain of mountains under water that goes from the North Pole to the South Pole

• When it cools they develop magnet and when magnetic field reverse than it changes polarization
• Sea floor is basalt (magnetite) when hot, poles are straight up
• Mariana trench is the deepest trench on earth

When continents were put to fit together the pole matched a common pole

• Concentrated along brittle boundaries
• Most earthquakes happen along the ring of fire

• Motion of the plates composing the Earth's lithosphere through subduction and seafloor spreading
• Lithosphere (rocky part of land) broken into plates, riding around like bumper cars
• Movement due to HEAT differential within Earth
• The edge of a continent may or may not consist with a plate

• Convection Cells (liquid portion) Mantel
• Cold = More Dense = Sink Down
• Hot = less dense = rise up

• Lithosphere
• Slab pull will cause land to converge, go underneath the lithosphere
• Push new layers

• Convergent - mountain/ island volcanoes
• The colder (ocean plate) and denser will go under and melt
• Divergent - coming apart
• Transforming Boundaries -
• 

Not Random -> Collections of them around tectonic plates

the worse earthquakes

• Rapid slip along the fault
• the elastic failue of the rock
• the stronger the rock the stronger the earthquake
• earthquakes can be seismic waves that come from the focus
• longer the time the force is applied = bend
• shorter time the force is aphe confiding pressureplied = break
• the confiding pressure
• temperature elastic behavior/ elastic failure

• Focus the physical position inside the earth
• Draw a line straight up from the focus it's the epicenter
• Fault the surface expression of the brakeage thrust fall

• 1. Destruction/ high death toll
• 2. Informationt About Earth's Interior - track earthquake and waves are received by seismometers, found about the temperature of the interior layers of the earth and the rock context
• 3. Seismology - valuable information about the shallow surface, where there are faults, oil and water sources
• 4. Formation & Exposure of Mineral Resources
• Copper was exposed through a fault
• 5. Contribution to GW and energy resources
• Oil Pools

• Building swaying/ pancaking
• Fire and explosion from fuel tanks and lines
• San Francisco huge fires
• Lisban, Portugal earthquake that caused a huge fire -> tsunami
• Liquefaction of sand and clay
• House, building, roads sink into the ground
• Landslides after the earthquake
• Philippines
• Tsunamis
• The after affects are the worse

• quantified earthquakes in roman numerals
• failed because of different levels of expertise/ human structure isn't always present/ depending material of buildings
• I: least damage - XII: worst damage

used today, shaking intensity to factor the geological material

was created for a specific area in San Francisco

• is a logarithmic scale of energy release
• Inverse relation between magniture and frequency
• The bigger they are the less frequent they happen

• P- compressional waves (fastest): the bunching up and expanding of waves
• S- Shear waves (hit next): more damaging than the P waves
• 

boundary between two media with different physical propertis (love and raleigh) SLOWEST but MOST DAMAGING

• P -> S -> Surface (doesn't include the large movements the can't be captured by the width of the paper)
• 

will get the 3 dimesional of the movement

• Radius of the circle s it can be anywhere within the radius
• Triangulation- network of seismographers
• Northeastern has a seismographer

• 1. Animal behavior: drop pressure, protp P wave can be identified
• Dogs
• Cats
• Snakes
• Aquatic Birds
• Horses

Stick- Slip Behavior (Kobe, Japan 1995)

• Disturbance layers tells you frequency
• Wetlands are region of constant of plant accumulation, pattern of inter-fingering and they knot up at the surface area, helps extend the historical record

• Parkfiel, CA 6.0 there will be another earthquake in Parkfield, California and it will be big
• Grey constant small earthquakes
• Red strained rocks, huge earthquakes even though less often

some change from water

• 1. The farther distance from epicenter the less damage
• 2. What is the Local Geology?
• San Francisco Marina District
• Unconsolidated sediment fill which is not safe to build on
• 3. Construction Methods
• How is your house built? (structural integrity)
• Mud, straw with heavy roof = BAD amplified movement
• Concrete with steel reinforcements = GOOD
• 4. Population, Density, Time of Day
• How many people are there?
• Where are they concentrate?

• We're learning that we can cause earthquakes by lubricating the faults, putting waste in our faults
• EQ's still very damaging and unpredictable
• Interesting proposal - Colorado, Rocky Mountain Arsenal
• Alaska most earthquakes

Boston is one of them

• Subduction zone earthquakes (convergent boundary)
• Juan de Fuca Plate -> North American Plate
• Caused the Seattle Needle to shake
• a pull apart area and the atlantic is a passive and moves along

• Arizona and Nevada
• Continental Rifting

• Volcano- related
• stic- slip behavior of the edges of the magma cooling
• Small earthquakes

• Ancient rift zone! (Reelfoot rift)
• Divergent
• New Madrid Earthquake rang the bells in Boston

• Near future there will be a huge earthquake
• Glacial rebound?
• Lithosphere that is used to a lot of pressure and it is doing a stick/ slip behavior
• Old pluton related?
• A pulse of magma which can cause a popping upwards
• Reactive of a rift system?
• SW/ NE regional compression?
• Squeezing of rocks will cause a popping upwards
• Fracture zone movement
• Stretching out of rock can cause a fracture
• Big ONE? Yes geologist have confirm a big earthquake
• Small earthquakes every other day
• Area of moderate seismic activity