1) Explain the difference between hazard, risk and vulnerability?
Hazard – Potential threat to humans and their welfare
Risk – Probability of loss (deaths, injuries, damage, disruption of
economic activity) as a result of a particular natural event
Vulnerability – Potential loss, or degree of loss, from the event
o 0 = no damage
o 1 = total loss
2) What is a DISASTER?
Disaster – A hazardous event affecting a community in an adverse
way such that essential social structures and functions are
3) What is the difference between Prediction/Forecasting and Mitigation?
Prediction & Forecasting – statement that a particular natural
hazard will occur with a given probability during a certain time
frame in a specified geographic area.
Mitigation – Efforts to reduce or minimize the effects of natural
hazards on a community
Mitigation usually occurs after a prediction/forecast is made.
4) Are Natural Disasters predictable?
Mother nature is non-deterministic
Individual events are inherently unpredictable
Thus, we use statistics such as probabilities based on past trends
– since we do not fully understand many natural processes.
5) What is a Recurrence Interval? Recurrence interval – Average time interval between the
occurrence of two events of given magnitude
i.e. a flood of 6 meters which happens once every 50 years.
(Recurrence interval of 50 years)…
means that there is a 1 in 50 chance that such a flood will
occur in any one year. ~Earthquakes~ 10/10/2012 6:37:00 AM
1) What is an earthquake?
The shaking or vibration of the ground
2) Where do earthquakes mainly occur?
Along plate boundaries
3) What is plate tectonics?
The study of the movement of plates
4) How many types of plate boundaries are there? What are they?
5) Where do the most powerful and destructive earthquakes occur?
The most powerful earthquakes occur at convergent margins
They can either be caused by a subduction zone, wherein a
heavier oceanic plate converges and then submerges under
a lighter continental plate OR it can occur when 2
continental plates collide, in which their buoyancy creates
compression pressures that trigger an earthquake
6) What happens at a divergent plate margin?
Plates are being CREATED
2 plates move away from each other and magma from the
lithosphere rises and cools creating new crust.
The movement of plates away from each other is known as
VOLCANISM is a common occurrence at divergent plate
margins, because the splitting and thinning of plates that are
moving away from each other allows magma to reach the
surface, stimulating volcanic activity.
7) What are convergent margins? Explain the different types that can occur. Convergent margins occur when two plates slide into each
Plates are being DESTROYED
There are 2 types of convergent margins:
o Oceanic plate converges with a continental plate. The heavier,
denser, oceanic plate slides under the lighter, buoyant
continental plate SUBDUCTION ZONE
o Two continental plates converge into each other. Since they
are both light and buoyant, they compress at a collision zone
Earthquakes that occur at convergent margins are large and
8) What is a transform margin?
A transform margin is a plate boundary in which 2 plates
slide past each other, neither creating nor destroying plates.
The San Andreas Fault is a transform boundary
9) Explain what the Pacific Rim of Fire is.
It is an area circulating around the pacific ocean from
southeast asia up and around down to the south western
coast of South America
This area has the most seismic and volcanic activity – mainly
due to the Subduction zones (oceanic plates converging onto
Very explosive, dangerious seismic and volcanic activity
occurs on this rim.
10) What is the relationship between faults and earthquakes?
Earthquakes usually occur along fault lines
Faults are planes of weakness along which the Earth has
Movements on a fault can be either slow (ductile
deformation) or fast (brittle fracture)
o A fast movement on a fault is what results in
earthquakes. 11) What are the 3 types of dominantly vertical faults
1) Normal Fault – Tensional Forces
2) Reverse Fault – Horizontal Compression
3) Blind Thrust Fault – Horizontal Compression
12) What are horizontal faults?
o They are a small-scale version of transform margins
o Strike is to the left and Slip is to the right
o Strike is to the right and Slip is to the left
13) What is the difference between a focus and an epicenter?
The focus of an earthquake is the point of origin of the earthquake
along the fault line
The epicenter is the vertical projection of the fault line on the
14) What is Elastic Rebound Theory?
Refers to how rocks return back to their original shape and stress
level after an earthquake
Before fault rupture, rock deforms after rupture, rocks return to
their original shape and stress level.
But not very useful for predictions
15) Explain Richter magnitudes.
Measures the MAXIMUM AMPLITUDES of ground shaking
during seismic activity
It is a logarithmic scale
16) How often do earthquakes occur? And at what magnitudes?
There are ~800,000 earthquakes a year of magnitude 2.0-3.4 (so
most aren’t even noticed by humans)
An earthquake of magnitude 8 or higher occurs once in every 5-10
years (those people notice) 17) What are some factors that affect the destructiveness of an earthquake?
Strength of buildings
Nature of soil or bedrock upon which buildings are placed
Other local conditions
Distance to Epicenter
18) What is the San Andreas Fault? (Type of Plate Margin)
19) Briefly describe the earthquake of April 18 , 1906.
20) Is it likely that there will be another big earthquake in the San Francisco
Bay area within the next 20 years?
21) What is Cascadia?
22) Why does Quebec have so much seismic activity?
23) What are some effects of earthquakes?
24) List some appropriate building codes which can reduce earthquake
25) What are signs of warning for an earthquake? %Hurricanes% 10/10/2012 6:37:00 AM
A hurricane is a warm core, low pressure system with no front
attached, that develops over tropical or subtropical waters
characterized by wind speeds of at least 74mph.
1) What are economic costs of hurricanes?
Rebuilding of damaged infrastructure
Cost of evacuation
Impact on energy production
Cost of severe coastal erosion
2) What’s the difference between a hurricane, typhoon and cyclone?
o Hurricane – Atlantic/Eastern Pacific
o Typhoon – Western Pacific
o Cyclone – Indian Ocean
3) Briefly list or discuss the stages of a tropical cyclone
Tropical Depression – the first sign of an organized circulation
Tropical Storm – System becomes named, some indication of a
Hurricane/Typhoon – Eye forms + Spiral Rainbands form
4) What is a warm core?
Warmest air is located at the center of the storm (the eye)
5) Discuss why there are few, if any, hurricanes along the coastal regions of
The ocean temperatures are too cold