a wave of energy that travels through the Earth, away from an earthquake in all directions.
move along Earth's surface, travel slower than S&P waves, are most destructive, produces up/down, back/forth, and around motions of the Earth's crust.
an instrument that records vibruation in the ground and determines the location and strenght of an earthquake
S-P time method
perphaps the simplest method by which seismologists find an earthquake epiceneter is the s-p the method.
the richter scale measure the ground motion from an earthquake and adjusts for distance to find its strength
a measure of the drgree nto which an earthquake is felt by people and the amount of damage caues by the earthquake,if any,is caues intensity
Mercalli Intensity Scale
a measure of the degree to which an earthquake is felt by people and the amount of damage caused by the earthquake, the intensity can range from I to XII
a hypothesis that a based on the idea that major earthquake is more likely to occur along the part of an active fault where no have occured for a certain period of time
is a weight placed in the roof of a building motion sensors detect building movement during an earthquake and send messages to a computer then signals control in the roof to shift the mass damper to counteract the building's movement
active tension system
work much like the mass damper system in the roof sensor notify a computer activater devices to shift a large weight to counteract the movement
act as shock absorbers durging an earthquake.They are made of layers of rubber and steel wrapped around a lead core.Base isolator absorb sesimic waves,preventing them from traveling through the bulding
are place between floors the braces counteract pressure that pushed and pulls at the side of a building during an earthquake
help prevent waterline and gas line from breaking engineers design the pipes with flexible jonts so that the pipes are able to twist and bend without breaking during an earthquake
how to calculate an epicenter . . .
scientists calculate the difference between arrival times of the P waves and S waves.
the boundary between tectonic plates that are sliding past each other horizontally.