Elastic-rebound theory

Stress deforms the crust until the stress is released. This is when the crust will snap back to its original shape, except it is now a bit out of place.

Stress between two plates will produce a fault (a break in the Earth’s crust) which then will eventually cause an earthquake to relieve the stress.

The focus is the location on the fault where stress if first released underground. The epicenter is the location on the surface directly above the focus.

This is where the most damage from the earthquake will be found. It is also good to know where this location is so you are aware that stress is building up at this location. It would be good to monitor these areas in case of further stress build up.

Earthquakes are found at any type of boundary, they range from shallow to deep. The depth is dependent upon the type of boundary.

It only takes a very small amount of energy release to produce a shallow earthquake. Plates moving only slightly can produce this amount necessary. Look at the plate tectonics map. Look at how many long plate boundaries there are. The potential exists all along these boundaries.

Subduction boundaries produce deep earthquakes because the crust is being pulled down further causing stress to build up at a deeper depth.

In waves of energy (p, s and eventually l waves)

P waves move back and forth; S waves move side to side; and L waves are up and down rolling waves

P waves travel through all materials; S waves only travel through solids; and L waves only travel on the surface of the crust.

P waves are the fastest, although their velocity does change; S waves are second; L waves are the slowest

P waves move back and forth; S waves move side to side; and L waves are up and down rolling waves

P waves move crust parallel to wave movement; S waves move crust perpendicular to wave movement; and L waves move crust perpendicular to wave movement

A seismogram is the instrument that collects data about earthquake waves, and and the seismograph is the actual print out of the data.

To find the distance to te epicenter from that location; they can also determine the magnitude of the earthquake at that location.

It shows the relationship between arrival times of waves and the distance that they traveled in that amount of time. It is used to determine the distance to the epicenter from each location.

You need at least 3 seismogram locations, from the data on the seismograph and a time-travel graph you can determine the s-p interval which will help you identify the distance the epicenter is from that location. Once you have the distance you can use a compass to draw the radius circle for each location. Wherever the 3 circles intersect is the location of the epicenter. Having more than 3 locations will give you a more accurate location.

This is where the most damage is, and this is a location where stress builds up.

The Richter scale measure the amount of energy released at the focus in magnitude 1-10, and the seismic moment measures the total amount of stress released by the entire fault also in magnitude 1-10.

No, because we do not have the technology to know at what particular moment that stress is going to be released at what exact location, and at what magnitude.