6th Grade Science - Earthquakes
Holt Science and Technology - Eatch Science. c 2005. Chapter 8
Terms
undefined, object
copy deck
- flexible pipes
- help prevent water and gas lines from breaking during an earthquake
- elastic deformation
- when the rock can only be stretched to a certain point before breaking(does lead to e quakes)
- S wave
- a seismic wave that causes particles of rock to move in a side-to-side direction, the secondary seismic wave
- Alabama's earthquake level is
- low
- theory that states that sections of active faults that have relatively few earthquakes are likley to be the sites of strong earthquakes in the future is called
- gap hypothesis
- West Coast
- part of the contenental US that has the highest earthquake-hazard level
- newest technology
- is what architects and engineers use to design and build structures to withstand earthquakes
- S-P time method
- the simplest method seismologists use to find an earthquake's epicenter
- XII
- is the highest intensity level on the Modified Mercalli Intensity Scale
- gap hypothesis
- a hypothesis that states that a major earthquake is more likely to occur along the part of an active faults that have had relativley few earthquakes in a certain period of time
- base isolators
- act as shock absorbers during an earthquake, makde of layers of rubber or steel wrapped around a lead core; absorb seismic waves to avert their travel through the building
- what are some plans you can make now for things to do during an earthquake
- find safe places in each room, make a plan with others where to meet after the earthquake
- what is the best thing to do if you are indoors during an earthquake
- crouch or lie face down under a table or desk in the center of a room
- Plate Motion: Convergent
- Fault Type: Reverse
- seismic wave
- a wave of energy that travels throught the Earth, away from an earthquake in all directions
- lowest level of intensity on the Modified Mercalli Scale describes an earthquake
- not felt by most people
- 18
- number of major earthquakes with magnitude 7.0 to 7.9 happen on average in the world each year
- active tendon system
- a weight in the building's base, similar to the mass damper
- deformation
- the bending, titling and breaking of the Earth's crust; the change in the shape of rock in response to stress
- common way to retrofit an older home for earthquakes
- is to securely fasten it to its foundation
- focus
- the point along a fault at which the first motion of an earthquake occurs
- Plate Motion: Divergent
- Fault Type: Normal
- body waves
- seismic waves that travel through the Earth's interior
- intensity
- is the degree to which people feel an earthquake and the amount of damage it causes
- plastic deformation
- deformation that is like clay, moveable, does not cause earthquakes
- retrofitting
- the process of making older structures more earthquake resistant
- seismogram
- first step in finding an earthquake's epicenter is to collect several of these from different seismographic stations
- when rock is elastically deformed, energy builds up in it - seismic wave occur as this energy is
- released
- seismologists
- are scientists who study earthquakes and sesmic waves
- areas along a fault where relatively few earthquakes have taken place are called
- seismic gap
- what can you do to make your home safer before an earthquake
- put heavier things on lower shelves and prepare food, water and first aid kits
- seismology
- the study of earthquakes
- earthquake hazard
- This measures how likley an area is to have damaging earthquakes in the future, it is determined by past and present seismic activity
- mass damper
- What is a weight placed in the roof that is computer sensored to move and counteract an earthquake
- how is the strength of earthquakes related to how often they occur
- the higher the magnitude of the earthquake, the less frequently they occur
- seismogram
- a tracing of earthquake motion created by a siesmograph
- seismograph
- an instrument that records vibrations in the ground and determines the location and strength of an earthquake
- aftershock
- an earthquake that occurs after a larger earthquake in the same area
- Plate Motion: Transfrom
- Fault Type: Strike-slip
- cross braces
- steel braces in between the floors that support the building during earthquakes
- earthquake zone
- area where earthquakes are common; where a large number of faults are located
- magnitude
- the measure of the strength of an earthquake
- surface waves
- seismic waves that travel along the Earth's surface
- Ricther scale
- measures the magnitude or strength of an earthquake
- elastic rebound
- the sudden return of elastically deformed rock to its undeformed shape
- seismic gap
- area along a fault where few earthquake have happened recently but where strong earthquakes have happened before
- P wave
- a seismic wave that causes particles of rock to move in a back-and-forth direction, the fastest seismic wave
- fault
- a break in the Earth's crust along which blocks of the crust slide relative to one another; due to tectonic forces
- not all seismologists believe that the following is an accurate way to forecast earthquakes
- gap hypothesis
- epicenter
- point on Earth's surface directly above an earthquakes starting point, or focus
- San Andreas Fault
- An earthquake zone in California where the Pacific Plate and the North American Plate slide past each other, frequently causing earthquakes
- what is the best thing to do if you are outdoors during an earthquake
- lie face down away from buildings, power lines and trees and cover your head with your hands
- 100
- is the number of times stronger a 5.0 earthquake is compared to a 4.0 earthquake (in magnitude)
- earthquake kit should contain
- flashlight, food that won't spoil, water, first aid kit, radio, fire extinguisher, medicine, batteries, clothes