Semester 2 Earthquake Material
The japanese myth about earthquakes was what?
a catfish
True/False: The most populated regions of the world are also places on the earth where earthquakes occur most often, mainly because many large cities were built long ago in costal regions used for shipping
true
True/false: Constructing earthquake-resistant buildings is cheaper than reinforcing older buildings to make them stronger
true
True/false: Like some other catastrophic events that occur on earth, earthquakes have had a part in shaping and reshaping the planet since long before recorded history
true
True/false: Scientists can know an earthquake's location depth, and magnitude within an hour of it occurring (anywhere in the world) thanks to the GSN
true
True/false: The US department of defense operates a specialized center to scan data from the GSN for evidence of nuclear tests
true
True/false: Today, seismic sensors are in locations as diverse as a dairy farm in Singapore, a snowy peninsula in Antartica, and a remote island nation in the South Pacific
true
True/false: earthquakes "interact," meaning that the stress changes produced by one earthquake can encourage others to occur nearby, thereby producing clusters of events
true
True/false:One of the greatest risks during an earthquake is personal injury falling debris
true
True/false:The San Francisco earthquake of 1906 sparked the beginning of modern seismology and helped scientists to develop the theory of plate tectonics
true
Why do earthquakes occur?
the energy that has been built up upon faults must be released - in the form of seismic waves
What is the location where the rupture of an earthquake begins and energy is released called?
the hypocenter, or focus
What is the hypocenter?
the point of failure where seismic waves originate
A wave that pulls and pushes through the body of earth moves the grounds how?
vertically
What are two events that do not relate to plate tectonics that can cause quakes?
volcanic activity and human activities such as mine blasting
What is a function the GSN does not serve?
weather research
Can people cause earthquakes?
yes
Do both types of body waves travel at a relatively constant speed?
yes
What is the most active seismic area on earth?
the ring of fire
What is amplitude also known as?
the swing of a wave recorded on a seismogram. By measuring this on the largest wave of a quake, seismologists determine the magnitude of a quake
Is there a limit to magnitude?
theoretically no - yet plates are limited in size, only so much energy can build up
True/False: If two seismograph stations receive data from an earthquake, the quake's location can be computed if P-Waves, S-waves, and surface waves have been received.
False
True/false: Stress forces from an earthquake get weaker as they move up a building
False: stress forces get stronger as they move up a building
What country believed that a giant mole caused quakes?
India
If two different seismograph stations receive data from the same earthquake, is it easier or more difficult to pinpoint the epicenter?
It is easier to pinpoint the epicenter as opposed to just one singular station receiving data
What are seismographs?
they are instruments that detect and record the movement and track the seismic waves generated by earthquakes
What is one catastrophic event that does not cause quakes?
extreme weather
True/false:The richter scale has a maximum magnitude of 10; it is not open ended
false the richter scale is open ended
True/false: A seismograph is a record of vibrations made by an earthquake
false: a seismograph records the vibrations, but a seismogram is a record of vibrations
True/false: Search and rescue dogs are used in the aftermath of an earthquake to locate survivors trapped in the wreckage of buildings. They are trained to track a scent by sniffing the ground
false: dogs sniff the air to track human scent within the wreckage
True/false: only about 10% of earthquakes are directly related to volcanic activity
false: only 5% of earthquakes are attributed to volcanic activity
True/false:The size and shape of a building does not affect its resistance to damage during a quake
false: size and shape does matter
True/false: The focus is also called the epicenter
false: the focus is the breakage point (also known as the hypocenter), whereas the epicenter is the point on the surface directly above the focus
What did Aristotle hypothesize as to how quakes are caused?
he thought that winds were drawn into the interior, which caused fires that swept through underground cavities trying to escape
How does an S-wave move the earth?
horizontally
What is magnitude a measure of?
intensity
What two things define the severity of an earthquake?
intensity and magnitude --> expressed in different ways
The Richter scale is a logarithmic scale, which means what?
it means that numbers are based on a scale of factors of 10
How many times more powerful is a magnitude 5.0 quake compared to a 1.0 quake?
it would be 10,000 times more powerful
What is magnitude versus intensity?
magnitude is related to energy released in absolute terms, intensity is a measure of effects on the surface (buildings, natural objects, humans, animals)--> represents the severity of shaking
What human events are capable of causing earthquakes?
mine blasts, nuclear explosions (underground tests), drilling for oil
Does a small earthquake precede larger quakes?
no, although foreshocks commonly occur before a quake, these are not necessarily considered as quakes. Most small quakes occur in isolation without a large event following
Where was the 9.1 earthquake that struck on Jan. 26, 2004 and resulted in tsunami that killed almost a quarter million people (227,898)?
off the coast of Sumatra, Indonesia
What did people in Europe believe caused earthquakes in the 1700s?
people believed that were a punishment or warning for those who were not sorry for their sins they had committed
What damage can be done to infrastructure by quakes?
power/gas lines can be ruptured or severed = fires
P-waves stand for what?
primary, or first waves
What are microquakes?
quakes below a magnitude of 2.0 that constantly occur throughout the world
What is the latest technology that has been adapted to serve the purpose of monitoring the movement of the crust?
radar equipment
What type of wave causes more damage to structures because of their design to hold more vertical weight than the structure's own along with ever-present gravity?
s-wave
S-waves stand for what?
secondary waves
The vibrations that are caused by earthquakes move in waves known as what?
seismic waves
What is synonym for seismometer?
seismograph
Why does pressure build along plate boundaries?
since plates have irregularities along their borders, while they move, they are halted by these irregularities which create friction, when these plates finaly break free from each other, the result is an earthquake
What sort of secondary effects can earthquakes produce upon the natural world?
slope instability, landslides
What do scientists use to locate the epicenter of a quake?
special math calculations are used to pinpoint the epicenter using a time distance graph
Why do the irregularities in the rock finally break creating an earthquake?
stress in the plate becomes greater than the strength of the rock
When earthquake energy reaches the surface, it is known as what?
surface waves
What tracks/detects the movement of earth?
the GSN-a global network of seismographs
What earthquake reinforced the belief of the 1700s that quakes were a punishment for wrongdoings?
the Lisbon, Portugal quake on Nov. 1, 1755
What are common metaphor can be associated with p and s-waves?
tortoise (s-waves) and the hare (p-waves)
How much time does each line on a seismograph represent?
30 minutes
What was the magnitude of the largest earthquake ever to hit georgia? When was it?
4.5 on March 3, 1914
How large must a magnitude be to be picked up worldwide?
5.0
What was the magnitude of the January 12, 2010 earthquake in Haiti?
7.0
What is the largest quake magnitude in recorded history since 1900?
9.5
What Russian god caused earthquakes?
According to Russian mythology, the god Tuli pulled the earth on a dog sled, and when the dogs stopped to scratch their fleas, earthquakes occurred
Where and when was the largest earthquake (recorded) in america?
Alaska, 1964
Where did ancient cultures believe that a frog caused earthquakes?
Mongolia
Which country believed that quakes were caused by their god kicking up his heels while dancing?
Peru
What type of wave causes the ground to move like the rocking of a boat?
Rayleigh waves
Do earthquake waves not follow?
a path
The South American(only some parts) myth about earthquakes was what?
a whale
Where are earthquakes most prone to happen?
active faults related on the boundaries of major tectonic plates
True/false: The Norse trickster, Tuli, caused quakes, imprisoned by the Gods and forced to lie on sharp stones while the venom of a poisonous snake dripped constantly on his face
false: the norse trickster's name is loki, not tuli, also snakes are venomous, not poisonous, that is why it drips venom, not poison
True/false: the richter scale is a scale of the measure of damage done by an earthquake
false: the richter scale measures the magnitude of a quake
Do P-waves travel faster or slower than s-waves?
faster, why the are primary
The shakespeare explanation to earthquakes was what?
"The Earth did shake when I was born" (Henry IV)
The main shock of an earthquake can trigger upwards of how many aftershocks?
1,000
When did Chang Heng invent the first quake detector?
132 A.D.
When could instruments effectively record vibrations?
1880
What are interesting factors in the Lisbon earthquake in 1755?
It was all saints day, buildings shook all over Europe, even the US was affected, 70,000 people killed, there were hideous aftershocks, fires burned, and there were sea waves
Who created the open-ended scale in 1935 at Cal Tech as a mathematical device to compare size of earthquakes?
Charles F. Richter
Where was the largest magnitude earthquake in recorded history?
Chile 1960
In which country did people believe that the earth rested atop the back of a giant tortoise and ox?
China
What is the network run by the USGS that is a permanent network of seismological sensors connected by a telecommunications network, serving as a multi-use scientific facility and societal resource for monitoring, research, and education, which has over 150 seismic stations distributed globally?
The Global Seismograph Network
What did the algonquin Indians believe caused earthquakes?
They believed that the earth reasted atop the back of a giant tortoise
What countries experience the most seismic activity? What plate causes this?
the USA, Canada, Chile, Japan, China, Indonesia, and the Philippines. These countries are along the Pacific plate boundaries, which is where 75% of all seismic energy is released
Where do quake waves travel through?
the body of earth
What event occurred in December of 2011 in Auckland, New Zealand that generated tremors?
a Foo Fighters concert where the crowd was jumping up and down
In what directions do earthquake waves move?
all directions
What is the magnitude of an earthquake measured by?
amplitude
Anything that generates seismic waves is known as what?
an earthquake
What is one thing earthquakes do not impact?
an increase in temperature
How many people were affected by the earthquake in Haiti? How many lost their lives?
approximately 3,500,000 affected, 316,00 estimated to loose life
Where is the focus located?
at the point of failure, it can be shallow or deep
What are P-waves and S-waves also known as?
body waves
What is intensity a measure of during a quake?
damage
What is one effect earthquakes can have upon the surface of the earth?
displacement of land
How are earthquakes unlike hurricanes, which can be monitored in their path of destruction?
earthquakes are unlike hurricanes because they are unpredictable
What accumulates before a quake?
energy builds up along faults, esp. close to the tectonic plate boundaries
