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French Unit 2 Study Guide

5.2: Changes in Factor Demand and Factor Supply

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Chapter 10 - Alcohols

GEOL 108, Crises of a Planet (Midterm)

Geology 108 Notes

1/15

What is a natural disaster?

Natural cause with negative impact
Sudden change
- Or not
High Death rate
Extensive Damage
- To structures
- Infrastructure
Minor events but occurring often

Emergency Manager Perspective

Expressed as a formula
R= H*E*V, Risk, Hazard, Exposure, Vulnerability

Sometimes a cascade

Many things relate to many others
- Harder to study
- Hard to evaluate
  - Need to consider odds of several things happening
- Easy to stir up irrational fears

FEMA Terminology

Four classes
- Emergency declaration (<$5M)
  - An unexpected event which places life and/or property in danger and required an immediate
- Major Disaster declaration (unlimited aid)
- Catastrophe (not official)
- Extinction level event (not official)

Four classes

Emergency declaration ( < $5M)
1. An unexpected event which places life and/or property in danger and requires an immediate response using routine community resources and procedures.
Major Disaster declaration (unlimited aid)
1. A disaster is an emergency considered severe enough by local government to warrant the response and dedication of resources beyond the normal scope of a single jurisdiction or branch of local government.
2. Often declared, come with resources, there were 47 in 2022, 70 in 2023.
Catastrophe (not official)
1. An event in which a society incurs, or is threatened to incur, such losses to persons and/or property that the entire society is affected, and extraordinary resources and skills are required, some of which must come from other nations.
Extinction level event (not official)
1. Geological evidence shows that they have happened on many occasions since multicellular life became abundant on the planet almost a billion years ago.

Potential to cause catastrophe
- Natural hazards vary greatly in their potential to cause a catastrophe.
- Floods, hurricanes, earthquakes, volcanic eruptions, large wildfires, and heat waves are the hazards most likely to have a high potential to create catastrophes.
- Landslides and tornadoes, because they generally affect a smaller area, have only a moderate potential to produce a catastrophe.
- Drought also has a moderate potential to produce a catastrophe because, although drought may cover a wide area, there is usually plenty of warning time before its worst effects are felt.
- Hazards with a low potential to produce a catastrophe include coastal erosion, frost, lightning, and expansive soils.
Toll of natural disasters
- Half of the total disasters (44 percent) occurred in Asia
  - where about two-thirds of the people (4.44 billion) on Earth live.
- Countries with medium-to-low income
  - suffered most from floods and storms.
- High-income countries
  - suffered greatest economic losses but lowest number of deaths.
- The United States, 0.34 billion people (4%),
  - experienced about 6% of the disasters.

Natural Disaster Cost

The average annual cost of natural hazards has increased dramatically over the last several decades
This is due to in part increase in world population
It is also a function of the increased value of properties at risk and to human spread to more hazardous areas

Toll of Natural Disasters in Perspective

World GNP is ~100 trillion dollars / year ($1014 dollars)
- US and Europe are each about $20T

World population is ~10 billion people (1010)
- US just 350 million

Natural disasters cost ~$100 billion / year ($1011)
- Locally traumatic
- Temporarily traumatic
- Small chance of much bigger ones
- Much of this cost is avoidable, the topic of this course.

Climate change could dwarf these numbers
COVID probably cost tens of trillions of dollars

1/17

Factor in fire?

Hydroclimate whiplash, an abrupt switch between very west and very dry conditions that is likely to occur more frequently as earth warms.
- The LA area received abnormally large amounts of rain in 2023 and early 2024, promoting plant growth.
- But less than 1 mm has fallen since 1 July, and brush and grass dried into tinder.
Real effect in study (for Asia), but projects only 3X effect by 2100
- Not yet a dramatic change
More people near wildland
- A factor that drove the intensity of the LA wildfires is the density of homes in steep terrain.
- Around the world, more people are moving into the wildland urban interface, where cities meet natural landscapes
- Fires that ignite at the interfaces can spread into purely urban areas with devastating results
- As population in the boundary zones grows, fires that start there are more likely to migrate into areas that are unequivocally urban, researchers say.
Academics in action
- Earth sciences research
  - How did smoke move through the basin
  - Effect of burnt run-off into the ocean
  - Landslides on the burnt surfaces
  - Samping pink fire retardants for metal pollution
- Caltech/JPL discussion
  - Can seismograms/satellites monitor fires in real time?
  - Already watching for landslides and lahars
- 80 person zoom in Viterbi
  - Engineering businesses to launch?
Disaster Agencies
- Federal Emergency Management Agency (FEMA)
  - The Federal agency that coordinates the response of Federal agencies to disasters and the communication of information about disasters between Federal agencies and the public, particularly within the first 48 hours following the event.

JFO, Joint Field Office
RSF, Recovery support functions
Communication Concepts and Systems
- Several systems are in place for communicating during disasters or alerting the general public to an imminent disaster:
  - Emergency Alert System
  - National Wireless Priority System
  - NOAA Weather Radio
  - National Terrorism Advisory System
  - Wireless Emergency Alerts
  - Radio (short-wave) Amateur Civil Emergency System (RACES)
- Social media can be an effective tool for communicating information to the general public and for situational awareness gathering.
Cal OES (California Office of Emergency Services)
- The California Governor’s Office of Emergency Services (Cal OES) began as the State War Council in 1943.
- With an increasing emphasis on emergency management, it officially became OES in 1970.
- In 2003, with the State increasing its focus on terrorism prevention after the attacks of 9/11, the Governor’s Office of Homeland Security (OHS) was established through an Executive Order by Governor Gray Davis.
- In 2004, the California Legislature merged OES and the Governor’s Office of Criminal Justice Planning, which was responsible for providing state and federal grant funds to local communities to prevent crime and help crime victims
- In 2009, the California Legislature merged the powers, purposes, and responsibilities of the former OES with those of OHS into the newly- created California Emergency Management Agency (Cal EMA).
- On July 1, 2013, Governor Edmund G. Brown Jr.’s Reorganization Plan #2 eliminated Cal EMA and restored it to the Governor’s Office, renaming it the California Governor’s Office of Emergency Services (Cal OES), and merging it with the Office of Public Safety Communications.

Los Angeles Emergency Management Department
- Big cities have this scale operation
  - Seattle, Portland, Los Angeles
  - Assigned chairs, lots of communications pre-configured
Ways to help
- Land use planning
  - Restricting where and what people can build
  - Almost any attempt to regulate land use in the public interest is likely to ignite political and legal opposition
  - Some are most concerned with economics, others with safety, others with the environment
- Insurance
  - Insurance for some natural hazards is simply not available. Landslides, most mudflows, and ground settling or swelling are too risky for companies, and each potential hazard area would have to be individually studied by a scientist or engineer who specialized in such a hazard
- Big government
  - Disaster assistance is often provided without a large cost-sharing component from states and local organizations. Thus, local governments continue to lobby Congress for funds to pay for losses but lack incentive to do much about the causes
- Public education
  - The best window for effective hazard reduction is immediately following a disaster of the same type
  - Studies show that this opportunity is short—generally, not more than two or three months
Role of Insurance
- Insurance brings significant benefits by
  - Promoting financial stability,
  - Helping relieve the burden on governments for providing protection of citizens via social security, encouraging loss mitigation, and
  - Generally making people more aware of the reality of risks and their consequences through information and pricing signals.
- The most significant contribution of insurance is the provision of risk sharing, risk transfer abilities and loss prevention measures.
- The security of insurance encourages high-value investments such as purchasing a house or spending money on infrastructure.
- The affordability of insurance is an important social issue.

US Disaster relief less when news is distracted

A study of the influence of mass media on U. S. government response to 5,000 natural disasters occurring between 1968 and 2002.
- These disasters took nearly 63,000 lives and affected 125 million people per year.
U. S. relief depends on whether the disaster occurs at the same time as other newsworthy events, such as the Olympic Games, which are obviously unrelated to need.
To have the same chance of receiving relief, the disaster occurring during the highest news pressure must have six times as many casualties as the disaster occurring when news pressure is at its lowest, all else equal.
Relief decisions are driven by news coverage of disasters and that the other newsworthy material crowds out this news coverage

Heat Waves
- Depends on country/state/location/organization
- Typically form near high air pressure system
- Example of how scientists choose a field
  - Geochemistry, atmospheric science, oceanography, stellar astrophysics.
The 2003 Europe Heat Wave
The 2010 Russia Heat Wave and Wildfires

Four biggest disasters

WWII
1918 Spanish flu
Great Chinese famine
COVID
- Population
  - USA- 340,000,000
  - World- 8,000,000,000
- Fatalities so far
  - USA- 800,000
  - World- 7,000,000
- Politicization of issues

Important Terms and Concepts

R=H*E*V
Some disasters are cascades
Dollar cost of natural disasters
Cycle of mitigation implementation
What is FEMA
Roster of chores in disaster response
Disparities of news coverage
Impact of the worst disasters in the century
Issues in the response to COVID

1/22

Plate Tectonics Notes:

Core, mantle, crust
Formation of the Earth
- In process of differentiation iron sank to center, lighter material floated upward to form crust
Earth’s history
- 15 Billion years (Ga), age of universe
- 4.5 Ga, age of solar system/earth
- 4.0 Ga, Mars size impactor→ Moon
- 3.9 Ga, small continents, Co2 atmosphere
- 2.5 Ga, large continents

Formation of the Moon

Giant impact
- Formed spray, which gradually coalesced
Capture theory
Multiple impacts
Co-formation theory
- Theories so far have fundamental problems
- All happened about 4.5 billion years ago

What’s Interesting about the Earth?

Quantities we want to know
- Motions, forces, stresses, viscosity, temperature, composition, history of planet, life
Quantities we can measure
- P & S wave velocities (seismology), density (seismology and gravity), surface rock, geochemistry, plate motions (geodesy), magnetic field and its history

1/24

LA Fire cost
- $250-275B
  - Previous record $200B hurricane Katrina in 2005
  - Worse than entire 2020 fire season
  - Might still go up
- $35-45B of it is insured
  - Low fraction slows recovery
  - Federal aid depends on Trump (and Congress)

Liquids versus solids
- Liquids flow: viscosity h resists
- Solids deform: rigidity G resists
- Maxwell characteristic time t=h/G
  - h is viscosity and G is elastic springiness
  - t = 10^-12 seconds for water
  - t = 10^6 years for Earth's crust
- Time scale of deformation < t: solid
- Time scale of deformation > t: liquid
- Examples silly putty, salt-water taffy, glacier ice, tar

Isostasy: crust is less dense than mantle, like wood floating on water
Crust is thicker where land is and thinner where oceans are
- That determines where our oceans are

Composition
- Crust
  - Oceanic
  - Continental
- Mantle
- Core
  - Fluid outer core
  - Solid inner core
Strength
- Lithosphere
  - outermost rigid layer
- Asthenosphere
  - weak layer below
- Lithosphere
- Mesosphere
  - lower strong layer

More central points
- There are about 10-15 big plates
- The boundaries between plates are faults
- Earthquakes are essentially the plates moving past each other jerkily.
- Three geometries where plates meet
  - Convergence
  - Divergence
  - Sideways (transform) motion

More points
- Earthquakes on boundaries
  - Mostly shallower than 50 km depth
  - Deepest earthquakes ~700 km depth
- Moves cm/yr, mantle 3000 km deep
  - Circuit takes ~ 1B years
    - π x 3x 103 (km r) x 102 (cm/m) x 103 (m/km)
  - Pangea ~200 M years ago
  - Rhodinia ~ 1B years ago
- More details in pre-lab reading
- Lab exercise on magnetic stripes

“Solid” Earth system
- Evolution of plate tectonics
Atmosphere and oceans
- Rise of oxygen
Rise of life
- Punctuated with big impacts

1/27

New study of heat deaths
- Now, cold deaths > 10 X heat deaths
- From now to 2100
  - Cold-related deaths are projected to fall
  - While those caused by extreme heat rise
  - 2.3M extra deaths
  - Heat total will be 50% more than cold total
- Affects elderly the most
- Amplified by heat islands in cities
- Mitigation actions are available
An Earth Timeline
- Hadean
  - 4.6 to 4 (Ga) Bya
- Archean
  - 4 to 2.5 Bya
- Proterozoic
  - 2.5 to 0.5 Bya
- Paleozoic
  - 500 to 250 Mya
- Mesozoic
  - 250 to 65 Mya
- Cenozoic
  - Since 65 Mya
Elastic Rebound
- A fault remains locked (by friction) while
  - Stress slowly accumulates
  - Gradually twisting the rock
  - Takes decades to centuries
- Then it suddenly slips in an earthquake,
- Releasing the stored-up stress,
- Takes seconds to minutes
- Energy is released
  - Surface that moved heats up
  - Vibration coming off produces sounds
  - Cracking of the rock, break the bonds
Ways to deform Rock
- Ductile: folding, stretching and thinning
- Brittle: faulting, often seismic
- Types of Stress: Compressive features, tensional Features

Convergent Boundaries
- Subduction zones- common, long lived
  - Continental or oceanic plate over oceanic plate
    - Explosive volcanism
Collision zones - shorter-lived (10 My)
- Continental crust hits continental crust, leads to mountain building
  - Both sides are too buoyant to sink
Continental plate over Oceanic Plate
- Plate boundary: site of largest earthquakes
- Eg: Peru Chile Trench
Subduction
- Elastic Rebound in a subduction zone
- Asthenosphere: a semi-solid layer of Earth's upper mantle that's located below the lithosphere
Thrust Fault- convergence
Normal fault-divergence
Divergent Boundaries
- Most frequently: mid-ocean ridges
  - Examples: mid-Atlantic ridge, many ridges under Pacific and Indian oceans
- Less frequently: rift valleys on land
  - Will turn into mid-ocean ridges once old land has spread far enough apart
Mid-Ocean Ridge Spreading Centers
- Plates move apart, new plate created
- Normal faulting
- Fewer and smaller earthquakes
- Brittle only at shallow depths (0-5 km)
- Far from civilization, little damage
  - Except in Iceland
Transform boundaries
- One plate slides sideways past another plate
  - Mostly ocean-ocean contacts
  - Some continent-continent contacts (like San Andreas fault)
- Least common boundary, usually vertical
Transform fault-contact between two plates that slide horizontally past one another, commonly connecting two mid-ocean ridges

1/29

San Andreas accumulation
- Wee see strain accumulate with GPS
  - Global Positioning System
- Steady strain rate over several centuries
  - Distributed across zone about 100 km wide
- Only top 20 km of fault are brittle and locked
  - Deeper rocks flow due to higher temp
- Earthquake prediction
  - If build up of strain is steady and featureless, there may be no clues of coming quakes
Terms and Concepts
- Formation of Earth
- Earth layering
- Convective motor of plate tectonics
- Cause of topography
- Three types of boundaries
Geodesy vs Seismology
- Somewhat separate issues
  - Geodesists study slow motions
  - Seismologists study fast motions
- Geodesy (GPS, LIDAR, InSAR)
  - Geodesy is better for longer periods, permanent.
  - Position to 1cm, maybe 1mm
- Seismology (seismometers)
  - Acceleration down to ground noise
  - Seismometers better for vibrations
  - 100(1000)-s period and faster
GPS Constellation
- 31 satellites
  - 20,000 km up,
  - 12 hours orbits,
  - Broadcast a signal back to Earth,
  - Takes at least 4 to determine location,
  - Usually 6 or more
- Accurate to about 1mm, 2mm vertically
- Selective availability:
  - Intentional errors,
  - 10m horizontally,
  - 30m vertical,
- For navigation:
  - Turned off in 2000
GPS (Global Positioning Satellite)
- Now “GNSS”
  - Global Navigation Satellite System
- We can watch the plates move
  - Guides cars, watches, kids’ phones
- Originally guided (and still guides) cruise missiles
InSAR
- Interferometric synthetic aperture radar
- Dedicated satellite
  - Sends out millions of signals
  - Then listens for each echo
  - Scans the ground with 100m square pixels

1/31

Geodesy shows grounds movement
- We can see how ground shifted in earthquakes (Pishan, China, 2015)
How faults break
- Rupture begins, at a place on fault where stress has exceeded strength
  - Crack spreads outward over planar fault surface from focus
  - 2-3 km/sec (near shear-wave velocity)
  - Rupture means sliding, releasing tectonic motion
- Larger area implies larger magnitude and longer duration of rupture
Energy released from cracking and sliding travels outward
- These vibrations are felt and cause damage
- Only a small amount of damage is caused by offset of the fault

Vocabulary

Focus - point where the rupture started (3 numbers)
Hypocenter - location (same as focus) plus the time of quake beginning (4 number)
Epicenter - surface projection of hypocenter (2 numbers)
Rupture - sliding of one side of the fault against the other
Trace - surface line of fault
Scarp - slope at the trace of thrust or normal fault

Vocabulary

No dominant pattern as to where hypocenter is on the fault plane
Generally, only part of a fault ruptures in each quake
Usually, big faults have been recognized beforehand
Many earthquakes do not break up to the surface
Sometimes several cracks with different orientations break at once in a single earthquake

Magnitude scales

Richter magnitude scale
- Logarithmic scale based on the maximum amplitude of ground motion, recorded on a standard seismograph, correcting for the distance to the source
  - M_L = log₁₀ (amplitude of seismograph) + distance correction
Mercalli intensity scale
- Rates quakes by how it feels
Seismic moment magnitude scale
- Depends on the rupture area. Provides better estimate of earthquake size for big earthquakes than the amplitudes recorded on a seismograph

Definition of Seismic Moment

M₀ = μ D S where
- μ is the rigidity of the rock
- D is the amount of slip (offset,
dislocation) between the two sides of the fault
- S is the surface area that ruptured
Units are force times length
Newton-meters, dyne-cm
Varies over many orders of magnitude

(Moment Magnitude)

M_W = 2/3(log M₀) - 6.0
- where M₀ is seismic moment in Newton-meters
Is now replacing other magnitude scales, such as
Richter magnitude or surface wave magnitude.
Provides a consistent measure of size of earthquakes from the smallest microearthquakes to the greatest earthquakes ever recorded

Magnitude vs fault rupture sizes

Magnitude 8 = 500 km
Magnitude 7 = 70 km
Magnitude 6 = 10 km
Magnitude 5 = 1.5 km
Magnitude 4 = 300 m
Magnitude 3 = 100 m
Magnitude 2 = 20 m

More factoids

Largest amount of slip is generally near the middle of the fault rupture plane
- Near the edges, there is less slip
Slip is generally in the same direction across the entire fault rupture plane
- (Not always.)

Fault planes do not open or close much,
- the two sides just slip sideways.
A point on the fault plane slips at a fairly constant rate
- around ~1 meter per second

What is a wave?

A wave is a disturbance that travels far through a medium while particles of the medium move only a small distance back and forth, and do not experience much net translation
- Science vs popular usage
Eg: ripples on a pond, the wave at sports events

Seismic wave radiation

Radiation- waves that travel carry energy outward
- Eg
  - Light energy from space heater
  - Water waves from a splash, few m/sec
  - Sound waves from a speaker, 300 m/sec
- Seismic waves (motions) are just vibrations of the ground, as sound waves are vibrations of the air

Generation of seismic waves
- P waves
  - Longitudinal, material moves back and forth (vibrates) in same direction that wave travels
    - Produces compression/dilation cycle
  - Fastest type of wave, so arrives first
    - Termed Primary or P wave
  - Typical velocities in crust: 5-7 km/sec
  - Travels through solids, fluids, or gas
    - Not vacuum, nothing to vibrate
- S waves
  - Shearing, material moves back and forth perpendicular to the direction
    - The wave travels in a twisting motion
  - Slower than P wave, arrives second
    - Termed secondary wave
  - Typical velocities in crust: 3-5 km/sec
    - P waves travel 5-7 km/s
  - Travels through solids, but not fluids
    - Because there is no restoring force for the perpendicular motions
- Surface waves, these do the most damage
  - Raleigh waves
  - Love waves

Ruptures are moving sources

Cracks spread along fault at 2-3 km/s
- Remember that “particle motion” is just ~1 m/sec, factor of 103 slower
Vibrations travel through rock at slightly faster speeds
- Speed depends on wave type
Some directions from earthquake receive more energetic shaking than other directions
- Different “radiation” patterns for P waves, S waves, Love waves, and Rayleigh waves

Where is energy?

In waves, energy has two forms
- Strain or deformation - like the energy stored by deforming a spring - 1/2 kx2
- Motion or vibration - kinetic energy in physics - 1/2 mv2
- Vibration is the most damaging, but either kind of energy can cause damage

Amplitude of seismic waves

Amplitude is strength of shaking
- Depends on magnitude
- Determines amount of damage, w/ duration
Amplitude decreases with distance from the earthquake
- energy spreading out over larger area
P wave smallest
- 3-6 km/s
S waves larger
- 1-4 km/s
Surface waves largest
- 0.5 – 2 km/s

2/3

Seismometer design

Essentials
- A heavy weight
- A way to record the motion of the weight
- A spring to keep the weight away from the sides
- A pivot so weight only moves in one direction
Luxuries
- Electronics to extend frequency response
- Far from sources of noise
  - An airtight box
  - A firm anchor for the seismometer
  - Burial for quiet surroundings, far from ocean and wind
Milne-Shaw seismometer
- One of first seismometers, globally distributed in 1890s
Data recovery
- Driving to recording site
  - Still often used
- Telephone lines
  - Bad during large quakes
- Microwave transmission
- Satellite phone
- Internet
- Cell modern
Modern portable seismic motion
- Buried seismometer with a wire to a computer with a big hard drive, plus batteries and a big solar panel
OBS, Ocean Bottom Seismometers
- Better coverage of Earth’s surface
- Very expensive
  - Hard to emplace
  - Can’t transit signals back
- Science targets
  - Oceanic volcanoes
  - Hot spots
  - Subduction zones
  - Detection of nuclear explosions
Refraction- object in water, rays kink

Because the waves travel at different velocities
- As waves radiate outward from the earthquake, through the Earth, they separate into a predictable pattern with
  - P waves arriving first, then S waves, then surface waves
    - P wave serves as a warning to take cover or shut down critical facilities
    - Warning ranges from a few to 100 seconds
    - Get 1-3 s of warning for each 10 km in distance
Epic SCEC simulations
- Nearly worst case for Los Angeles
- Run on large supercomputer
- 4x real time
- Basis for Shakeout, statewide exercise for preparedness

Important Terms and Concepts

How GPS, InSAR, and LIDAR work
Use for plate tectonics, earthquakes, & volcanoes
Seismic wave speed vs earthquake rupture velocity
Concept of a wave
Meaning of moment and magnitude
Seismometer principles
P, S, and surface wave properties
Wave reflection and refraction

2/5

Santorini alarm
- Accelerating swarm of earthquakes
  - Mainly in last week
  - Up to M5s
  - Near famous supervolcano
- Not that dangerous
  - Moving away from volcano
  - 1/20 chance of a bigger quake after every earthquake
  - For a swarm, just sum over all quakes
  - Change of an M7 not so large, wouldn’t be that damaging
- Probably either
  - Magma moving underground
  - Or water percolating underground
  - “Slow slip” progressing along fault
3 levels of predictability
- Time Independent Hazard
  - Earthquakes are a random process in time
  - The recent past doesn’t matter
    - Except to set long-term earthquake rates
  - Such calculations can be used in
    - Building design and and planning of land use
    - For the estimation of earthquake insurance
- Time Dependent Hazard
  - Include a degree of predictability in the process
    - The seismic hazard varies with time
  - Perhaps the hazard increases with passing time after the last event
    - characteristic
  - Or seismic hazard instead decreases with time
    - Due to the tendency of earthquakes to cluster in space and time
- Aka Earthquake forecasting
  - We predict risk of an impending earthquakes on a time scale of minutes to years
  - The forecast is probabilistic
  - Relevant authorities might prepare for an impending event weeks to months ahead of time
  - Practical roadblocks include
    - Identifying reliable precursors
    - The likelihood of missed events or false alarms, involving changes in behavior for up to several months, resulting in a loss of public confidence
- Deterministic prediction
  - Earthquakes are inherently predictable
  - We reliably know in advance
    - Their location (latitude, longitude and depth),
    - Magnitude, and
    - Time of occurrence
  - Benefits
    - Planned evacuations,
    - Machines in safe positions, and
    - Prepped for recovery
Probability
- How often you expect something to happen
  - Example - flipping a coin lands on heads 50% of the time
- Reported as percent (50%), decimal (0.5) or fraction (1/2)
- Must be between 0% and 100%
- We may say for an M>7 in the next 30 years
  - 80% probability
  - 4 out of 5 chance
  - 0.8, and it matters which
- And we can’t repeat the game
  - Or even easily check how well it’s working.
Hazard and Risk
- Hazard – probability that an area will be shaken
- Risk – Probability of a loss
- Hazard is what seismologists predict
  - Includes earthquake probability
- Risk is what insurance companies, the government, etc. need to know.
- Risk = hazard vulnerability value
Seismic Hazard
- I - Estimate future long-term seismicity rate from
  - Use past locations of felt earthquakes,
  - Fault locations and geological recurrence times
  - And deformation rates
- II - Calculate ground-shaking probability
  - From source-magnitude probability and
  - Path and site effects
- Such calculations can be used in
  - Building design and planning of land use
  - For the estimation of earthquake insurance.
- Remember uncertainty!
Probability of damage
- Find the faults
- Find faults' segmentation
- Find segment properties
  - Magnitude
  - Recurrence interval
- Sum up motions from all segments of all faults
  - Hazard
- Then figure out expected
- Damage
  - Risk
Fault Zone Segmentation
- Characteristic quake model
  - Only one segment breaks at a time
- Segments defined by
  - Ends of fault traces
  - Fault intersections?
  - Changes in rock type along fault?
- Best guesses - segment defined from prior quakes.
- Not clear whether the concept of fault segmentation is accurate or useful.
History of Wasatch Fault Segments

From this history

10 events in 1300 years
- An event every 130 years, on average
- About 25% chance in next 30 years
- (that’s 30 years / 130 year repeat time)
But we know the history
So another guess would be
- Last event 167 years ago
- They’re overdue!
But events are not regularly timed
- Clustering model?

Consensus of experts

New Zealand example, the “Cooke method”
- 2017, NZ government gave us a test
  - Weighted our forecasts by how high we scored
- Gave us the NZ facts to assess
- Then announced earthquake danger as estimated by experts

Cost Benefit Analysis

Benefit-cost ratio:
- Calculate annual benefits
- Multiply by lifetime
- Calculate projected cost of special earthquake construction
- Take ratio to get benefit/cost ratio

Would it be better to spend money on new schools, hospitals, etc.

Or not spend it at all
- (i.e., cheapskates WA & OR)

Definitions

Sequence: Set of quakes that are related
Foreshock: Quake followed by a bigger quake in same sequence
Mainshock: Biggest quake in a sequence
Aftershock: Quake after the biggest quake in a sequence
Corollaries: One never knows that an event is a foreshock until the
mainshock comes along
1. Aftershocks can turn into foreshocks

Difference between mainshocks, foreshocks, and aftershocks
- Little to None

Mainshocks

Largest magnitude earthquake in a sequence
Larger mainshocks
- Longer fault
- Longer duration of rupture
- Bigger peak slip
- Bigger strain larger volume of rock
- Have more aftershocks

2/7

Forecasting and Prediction
- Prediction framework
- Earthquake statistics
- The right way to forecast
- And arguing with Russians
- And others
NSF Cuts?

Foreshocks

Smaller earthquakes that precede the mainshock
- Often by just hours
Few in number
- Only half of mainshocks have even one foreshock
Near mainshock hypocenter
- Part of the nucleation process
Equal chance of M1, 2,3…

Aftershocks

Smaller earthquakes soon following the largest earthquake of a sequence (the mainshock) near mainshock rupture zone
- Follow almost all shallow earthquakes
- Cover ruptured area
- Can number in thousands
- Can last for years or decades
- The most predictable (and well-studied) earthquakes
Cause of aftershocks?
- Every time there is an earthquake,the volume of rock around the rupture is strained, that is, twisted or squeezed
- Sometimes, the strained rock breaks
- Often, it takes a while for it to break, so the aftershocks may appear seconds to years after causative quake
- But we don’t know for sure why there is a delay
  - Cracks growing
  - Viscous rocks slowly flowing
  - Fluids percolating

1989 M6.9 Loma Prieta example

40-50 km long thrust rupture
- On San Andreas?
Extends to 12 km depth
Slightly dipping to southwest
Focus near middle of bottom of rupture
Two M 5 foreshocks 6 months earlier
- Very near focus, “prediction”
Aftershocks
- Fill rupture zone

Distribution of sizes

Like for mainshocks, there are many more small aftershocks in a sequence than big aftershocks
If mainshock has M 6
- 1 or 2 aftershocks with M 5 to 6
- 10’s of M 4 to 5
If mainshock has M 8, an M 7 aftershock is likely
Omori’s Earthquake
- The decay of aftershock activity following the 1891 Nobi, Japan, earthquake... for over 100 years!
To make an earthquake prediction need to state:
- Time interval in which quake will occur
- Region in which quake will occur
- Magnitude range of predicted quake
  - Small quakes occur more commonly
  - Easy to predict there will be magnitude 3 somewhere in SoCal next month, but not useful
Possible precursors
- Change (increase or decrease) in number of earthquakes
  - For example, foreshocks
  - Difficult to distinguish such changes from random variations
- Ground uplift or tilt
- Radon emission
- Electrical resistivity
- Seismic wave velocity
Clustering of seismicity
- Whenever there’s a quake, it becomes more likely that more quakes will come soon
  - 5% chance that any quake will be followed by a bigger quake in a week
  - With passing time (and no quake) , odds return to normal
1997 - Quake panel admits prediction is difficult
- The leaders of the program have always maintained that prediction of the Tokai earthquake is possible
  - The M8 Tonankai earthquake that occurred in the same region in 1944 showed “clear precursors” that could have acted as a warning.
- The Japanese government has approved a report by seismologists that clearly admits for the first time that earthquake prediction is difficult
China discouraging predictions
- Unofficial earthquake warnings
  - 30 in the last 3 years
  - Brought factories and business to a halt
  - None has been accurate
- New law
  - Requires high standard of scientific reasoning
  - Or else predictors will be penalized
  - Being enforced with latest earthquake
9/29/16 L.A. Earthquake Advisory
- USGS monitors seismicity
- USGS issues warnings
- No other entity!
Many wacky predictions
- 1/12/99: “The world has been void of M6 quakes for too long. Expect an M6 or larger in China or New Zealand.”
- •1/27/99: “Well, the M6 hit in Columbia, not in China, and unfortunately in a populated area.
- Damage is severe.”
  - Douglas Ian McKenzie
  - Physics degree at Sonoma State University, mechanical engineer
  - Complained to my Chair about class web page on prediction
Real Predictions
- Parkfield seemed to repeat every 22 years
  - Was supposed to happen in 1989 or so
  - Lots of equipment put out in 1980s
- Broke in 1857, 1881, 1901, 1922, 1934, 1966?
- We finally got the quake Sept 2004
  - Last week someone mentioned it’s due again.
- Or were those really similar events?
- (Easy to misinterpret spurious patterns)
Still today
- Friedmann Freud at “NASA”
  - Tricked Nature in 2014 news article
  - Rocks spark and heat and charge before quakes!
  - Only he knows “physics”
- Earthquake lights
- Warm ground
- Animal anomalies
- Good scientist in his field
GEOCOSMO REAL EARLY WARNING SYSTEM
- Provides 2 to 3 days lead time before any major earthquake
- Satellites on geostationary and low-Earth orbits
- Regional ground station networks and other ground assets
- Monitors the range of signals that the Earth produces when stresses build up deep below to dangerously high levels, heralding an increased probability of a major seismic event
- Never again a major earthquake will strike “out of the blue”
- Occasional false positives have to be accepted
- Disappeared in 2023!
Vladimir Keilis-Borok
- Invented complicated but sensible method
  - Claimed it was 5-10 times more powerful that it really was
  - Kept changing parameters so it retroactively worked better
- Very distinguished scientist
  - Member of 7 National Academies
  - Came with references from a Nobel Prize winner
  - Played major role in nuclear weapons treaty negotiations
- I suggested he put out a press release documenting his results
- It mentioned an ongoing prediction for LA
  - 50% chance of M > 6.4 in 9 months
  - Really more like 5%, included desert to the east
  - The press ran with it
  - Luckily, it didn’t happen
After prediction failed
- KB claimed forecast had only a claimed chance of 50%
- Subsequent predictions pushed successes down to a random rate for the next 18 forecasts, with zero successes
  - Seemed completely useless
- Further analysis suggests a success rate 2-4 times random guesses
  - More powerful than guesses, but much less than 50% success.
- KB passed away in 2013
- His collaborators continued and attacked others’ forecasts.

Some important terms and concepts

Three levels of forecasting and predictability
Hazard vs risk
Process for estimating seismic hazard
Expert consensus
Foreshock, mainshock, aftershock
Three prediction requirements
Only precursor so far – seismicity clustering
Past and current skepticism of prediction among experts

2/10

California Earthquake Awareness

Historical Earthquakes and Seismology
Moderate earthquakes have occurred in Massachusetts, impacting brick chimneys and stone walls without causing recorded deaths.
Early earthquake investigations led to the establishment of geological surveys and societies, and the introduction of geology courses in colleges.
Robert Mallet, an Irish engineer in the 1850s, was a key figure in early seismological research. He is considered the "father of seismology". Mallet compiled historical earthquake catalogues and created maps showing areas disturbed by earthquakes.
John Trask compiled annual earthquake lists published in the proceedings of the new California Academy of Sciences from 1856 to 1865.
John Branner implemented a corps of observers who noted the time and intensity of earthquake shocks, sending these notes to the compiler with minimal delay. Branner started a "felt" catalog in 1916.
The 1906 San Francisco earthquake led to advancements in science but also a cover-up of the danger.

General Overview

The presentation covers earthquake science and policy.

It includes an introduction to natural hazards and how earthquakes work.
It aims to increase California earthquake awareness and discuss earthquake early warning systems.

Historical Earthquakes and Seismology

Moderate earthquakes have occurred in Massachusetts, impacting brick chimneys and stone walls without causing recorded deaths.

Early earthquake investigations led to the establishment of geological surveys and societies, and the introduction of geology courses in colleges.
Robert Mallet, an Irish engineer in the 1850s, was a key figure in early seismological research. He is considered the "father of seismology". Mallet compiled historical earthquake catalogues and created maps showing areas disturbed by earthquakes.
John Trask compiled annual earthquake lists published in the proceedings of the new California Academy of Sciences from 1856 to 1865.
John Branner implemented a corps of observers who noted the time and intensity of earthquake shocks, sending these notes to the compiler with minimal delay. Branner started a "felt" catalog in 1916.
The 1906 San Francisco earthquake** led to advancements in science but also a cover-up of the danger.

Mitigation and Preparedness

Progressivism- among scientists and engineers in California's history has influenced approaches to hazard mitigation.

People prepare for future earthquakes by constructing sound buildings and developing contingency plans.
Following the 1906 San Francisco earthquake, efforts were devoted to mapping the state’s earthquake risks and urging improved construction methods.
A committee recommended a network of seismometers reporting to a central bureau to improve seismographs and a group of cooperating observers to report quake information to create a catalogue of earthquakes on the Pacific Coast.
After the San Fernando earthquake, engineers strengthened building codes without extensive lobbying.

The Politics of Hazard Mitigation

Some Californians viewed destruction by earthquakes as inevitable and unalterable, favoring "dogged persistence and denial" as a response.

Following the 1906 earthquake, Mayor Eugene Schmitz and others downplayed the disaster to avoid scaring off financing for rebuilding the city.
In the mid-1920s, Bailey Willis gave speeches, newspaper interviews, and cultivated allies to convince engineers, architects, businessmen, and the general public of the need for a concerted public relations campaign.
After the 1925 Santa Barbara earthquake, the Chamber of Commerce sent pictures showing minimal damage, and a group of bankers telegraphed eastern cities emphasizing that reconstruction did not require assistance from non-Californians.
Robert T. Hill was offered money to write a formal brief to counteract Willis’s prediction.
A major Caltech donor threatened to cut off funding for earthquake research, leading to a reluctance to publicize warnings.

Earthquake Prediction Efforts

In 1905, Akitsune Imamura predicted Tokyo would suffer a great earthquake, but Omori denounced this prediction.
The Ad Hoc Panel on Earthquake Prediction reported to the President’s Science Advisory Committee in 1965.
By 1970, most agreed that the sections of the San Andreas Fault that had ruptured in 1857 and in 1906 posed the greatest hazard for the future.
Louis Pakiser of the U.S. Geological Survey asserted that experts would be able to predict earthquakes within five years if research funds were forthcoming.
In January 1974, Jim Whitcomb (Caltech) predicted that a magnitude 5.5 earthquake would strike near Riverside in early 1974. There was indeed a strike-slip earthquake just east of Riverside on January 30, albeit only of magnitude 4.1.
In 1975, the Chinese successfully predicted the Haicheng earthquake.
In April 1977, Caltech’s Whitcomb predicted an earthquake of magnitude 5.5 to 6.5 in the Los Angeles basin within the next twelve months.
The Palmdale Bulge, an uplift along a segment of the San Andreas Fault, raised concerns and led to increased calls for prediction research funding.
On July 28, 1976, a magnitude 7.6 earthquake hit the Chinese city of Tangshan without any effective warning.
By 1979, most of the Palmdale bulge had deflated without a great earthquake.
The 1979 magnitude 5.7 Coyote Lake earthquake struck within the most heavily instrumented portion of the San Andreas fault zone, but no anomalies were found in the data recorded before the earthquake.

Building Codes and Safety Measures

The 1933 Long Beach earthquake led to the Field Act and local building codes with earthquake provisions, increasing the earthquake resistance of California’s building stock, especially schools.

The state geologist delineates a zone centered on active faults to limit building. Any fault showing movement within the past 11,000 years is deemed active, with construction restrictions within 50 feet.

Funding and Research

Earthquake engineering and seismology came to depend on funding from military agencies and the National Science Foundation.
From 1958 to 1961, federal support for seismology jumped sixtyfold, from $500,000 to $30,000,000.
In the mid-1970s, budget cuts targeted earthquake research.

More Recent Events

More recent events in 1971, 1989, 1994, and 2014 near California cities have fine-tuned problems and fixes.

The 1994 Northridge earthquake (MW = 6.7) caused $40-50 billion in damage and occurred on a previously unknown fault.
The 2014 South Napa quake (M = 6.0) caused many injuries, no deaths, and an estimated $300M in damage.

Important Terms and Concepts

Cause of earthquakes unknown until ~1900
Initial efforts constructed catalogs with observers
1906 San Francisco event- science advanced, cover-up of danger
1923 Tokyo earthquake- great disaster
Bailey Willis and 1933 Long Beach- teaching danger to Californians
Nuclear weapons and power plants– new uses for seismology
1970s efforts at prediction- spawned research but few predictions
More recent events in 1971, 1989, 1994, 2014 near California cities fine-tuned problems and fixes

2/12

3 M3.5 Quakes on the San Andreas
- 21 concentrated events total
  - 5-8 km depth, probably more compact
  - 0.5 km spread in map view
- 2 of M3s on 10th, 1 on 11th
Scares people
But 5% chance rules says
- Tiny chance of danger > M5
If GPS moves, then worry

Likely damage pattern

Fire was the biggest problem
- Water mains broken
Burned for 3 days
- Stopped by dynamited fire breaks
Caused some new building codes

Seismological Society of America

Distrusted seismometers for locating faults
John Branner implemented a corps of observers
Branner started “felt” catalog in 1916
Harry O. Wood built seismometers
Bailey Willis worked with Wood to map the faults of CA issued in 1923
Robert T Hill was best known for work on geology and petroleum resources in Texas

Tokyo 1923

M7.9
Great Kanto earthquake
World’s 3rd largest city
143,000 killed
600,000 houses destroyed

1925 Santa Barbara Earthquake

On June 29, 1925, an M6.8 earthquake
Numerous brick and reinforced concrete structures in the central business district were destroyed
12 people killed and scores more injured
Crumbling buildings

Santa Barbara quake response

Chamber of Commerce sent more than a thousand pictures via air mail to newspapers nationwide ostensibly showing that damage had been minimal.
The president of a group of bankers also sent telegrams to about 20 eastern cities emphasizing that reconstruction did not require assistance from non-Californians.
The San Francisco Chronicle stated that Maine and New York were as much subject to earthquakes as California and that no place could claim to be safe from natural calamities.

1927 Lompoc earthquake

Nov 4, M7 earthquake
Landslides, railroad disruption
2m tsunami
Killed or stunned many fish
Not far from current Diablo Canyon nuclear power plant

Insurance companies awaken

The cost of earthquake insurance increased 5-10 fold after the Santa Barbara earthquake
A survey showed that most buildings in CA were not earthquake resistant

Progress in early 1930s

Rugged instruments capable of recording even the strongest motions were developed
45 strong motion seismographs installed across the state
Several earthquake recorded in these years showed spikes of motion in which accelerations exceeded 0.10g
Initiation of work on the Uniform Building Code for CA

1933 Long Beach Quake

M6.4 on Charles Richter’s new earthquake scale struck near Long Beach
- 120 deaths
- At least $40 million in property damage

Improvements post-1933

The Field Act and the numerous local building codes that now included earthquake provisions increased the earthquake resistance of much of California’s building stock, especially its schools
90% of city schools were strengthened
Reconstruction project cost more than $30 million

After WWII

Not much damage, not much progress
Seismologists turned to the new civil defense orgs
Federal support for seismology research increased a hundredfold
Seismologists and engineers rejected tactics employed by grassroots activists

Change of focus

Charles Richter on seismology
As the 1950s passed without any military attack on the continental United States, civil defense groups expanded their activities to include natural hazards as well as military threats

Scientists integrated with agencies

When experts decided to push more vigorously for expanded seismic safety measures in late 1960s and 70s

2/14

California mitigation

1964 Good Friday earthquake- Plate tectonics

1960 M9.5 earthquake in Chile
Instruments improved
On Good Friday, March 27, 1964, M9.2 (9.4?) earthquake struck Alaska

Prediction Program

Seized the opportunity to lobby for a comprehensive national research program
Frank Press was leading seismologist
Earthquake prediction research program focus
Study fault zones in Ca, Nevada, and Alaska
Seismographs, strainmeters, magnetic, and gravity devices on fault zones
$137 million over several years

Hard to Sell

Only about 10 US deaths per year
Leaked panel’s deliberations to the news media
Newspapers responded enthusiastically to earthquake prediction
In the late summer of 1965, the proposal was released even w/o gov endorsement
Earthquake prediction only a heightened risk over several weeks or more
Real estate values, public morale, suffer greatly
UCSB social critic Garret Hardin
Charles Richter
Press panel saw engineering as less impt than earthquake prediction or other geological research
Increased funding proposed for earthquake engineering
Report was not publicly released until after presidential election

Incremental progress, new report

By 1970, most agreed with Clarence Allen that the sections of the San Andreas Fault ruptured in 1857 and 1906 posed hazard for future
San Andreas Fault became densely instrumented

1971 San Fernando earthquake

M7.1
- 6 am on Feb 9, 1971
- 65 deaths
- $500M in losses
- 30,000 buildings had been damaged
- Iconic San Fernando Mall damage
Very similar to 1994 Northridge
Freeways vulnerability exposed, unexpected damage to some buildings, nearly breached a big dam

Progress After Quake

Engineers strengthened building codes without having to lobby legislators or general public
Seismic design provisions needed strengthening
Codes were changed to address problems

1972 Alquist Priolo Law

Limits building on a one-quarter-mile-wide zone centered on sufficiently well-defined and active faults

Dilatancy-diffusion theory

Rock dilate as they near failure, as numerous tiny cracks form and open up (when stress builds up near an earthquake fault)
- Vp, Vs change, ground swells and tilts, radon comes out, etc
- Complex pattern over time

Complex Theory

Normal way to do science
Everyone takes a guess
Useful result integrate and generalize

Haicheng 1975

Lots of foreshocks, which is not usually the case, 100,000s of lives saved

1975 Palmdale Bulge

From leveling surveys along 5 routes across southern San Andreas Fault
Along all 5 routes, surface bulged up by 6-10 in
Greatest amount of uplift occurred near town of Palmdale in northern LA county

Demise of Dilatancy-diffusion

On July 28, 1976, a magnitude 7.6 earthquake hit the Chinese city of Tangshan, about 100 miles east of Beijing, without any effective warning, killing perhaps 1,000,000 people
In 1976, Whitcomb quietly withdrew his prediction
By 1979 most of Palmdale bulge had deflated w/o earthquake

National Earthquake Hazard Reduction Program

NEHRP- a legacy of the optimism over earthquake prediction of mid-1970s
- And concern over seismic disaster foretold by Palmdale Bulge and Whitcomb prediction

1994 Northridge Earthquake

Jan 1994
Mw = 6.7, 20 by 20 km, 1-2m slip
Buried fault (blind thrust fault)
- Focus at deepest part of fault (18 km)
- Rupture did not reach surface
- On previously known fault
Still few aftershocks
$40-50 billion damage

2014 South Napa Quake

M = 6.0
- Many injuries, no deaths
- Damage estimated at $300M
- Long term impact $1B
- Many wineries reported losses
Not on a main fault
- Complicated surface rupture
Lots of afterslip

Impt Terms and Concepts

Cause of earthquakes unknown until 1900
Initial efforts constructed catalogs with observers
1906 SF event science advanced, cover-up of danger
1923 Tokyo earthquake great disaster
Bailey Willis and 1933 Long Beach teaching danger to Californians
Nuclear weapons and power plants- new uses for seismology
1970s efforts at prediction-spawned research but few predictions
More recent events in 1971, 1989, 2014 near Ca cities fine-tuned problems and fixes

2/19

Earthquake Hazards

Bay Area Soil conditions

Correlates with damage pattern
Strongest damage on water-deposited sediments

Soft ground areas

Mexico City badly damaged in 1985
M8.0 quake 400 km away
Extremely soft soil
10K deaths
Soft site common: LA, Bay Area, Tokyo, Salt Lake City, Anchorage, Boston, Istanbul

Extreme case: Soil Liquefaction

Santorini

Generally, quake hazard is from ground shaking
But fault trace ground shift can be devastating right on fault trace
Both greater ground shift and ground shaking in fault zone

Hazards of Faulting

San Andreas Fault zone in the Carrizo Plains
- Imagine tearing on fault trace
- And soft ground near fault
- How close is dangerous?
Generally, quake hazard is from ground shaking
- But fault trace ground shift can be devastating right on fault trace
Both greater ground shift and ground shaking in fault zone
Few structures can withstand ground rupture

1972 Alquist-Priolo Law- fault zone danger

Fault scarp in Nevada, 1954
Building straddling fault in Nicaragua, 1972 earthquake
1971 San Fernando quake
Hayward fault and stadium
UC Berkeley campus
SF water supply 1906

LA and aqueducts

Three major aqueducts feed 88% of LA’s water
An earthquake on the San Andreas could destroy key sections of the aqueducts, cutting off the water supply for more than 22 million people in SoCal
Los Angeles lags the San Francisco in this effort

Denali Fault rupture

Engineers estimated that the pipeline could be subjected to a magnitude 8.0 earthquake in which the ground might slip 20 feet horizontally and 5 feet vertically
The rupture crosses the pipeline within the 1,900 foot corridor

Daly City

San Andreas fault runs through it
Zoning ignore the fault

Relation of danger to faults in big quakes

Worst danger near faults
Most damage within 50 km
Occasional pockets of damage out to 100-200 km from rupture
Strongly depends on one’s building and setting

Soft sites: Soil Effects

Strength of shaking depends
- On earthquake size
- On distance to earthquake
- On “site effect”
Dangerous geology
Softness can vary on a fine scale
1906, for example, near-surface geology matters
Bad soil conditions
- Correlates with damage pattern
- Strongest damage on water-deposited sediments
- LA, Seattle, Bay Area