15.3 Flashcards
magnitude
measure of energy released during an earthquake
can be described using the richter scale
richter scale
numerical rating system use to measure the amount of energy released during an earthquake
amplitude
size of seismic waves
increase of 1 on the scale represents an increase in amplitude of a factor of 10
moment magnitude scale
scale used to measure earthquake magnitude using values that can be estimated from the size of several types of seismic waves
what does the moment magnitude scale take into account
1) size of the fault rupture
2)rocks stiffness
3)amount of movement on the fault
modified mercalli scale
measures earthquake’s intensity on a scale from l to Xll
intensity
the amount of damage caused by an earthquake
the higher the number, the greater the damage
surface waves gradually ___________ in ________ with _____________ _____________ from the focus of an earthquake
decrease, size, increasing, distance
Depth of the Focus
another main factor in determining the intensity on an earthquake
shallow focus earthquakes make up how much percent of continental earthquakes
90%
Intermediate focus earthquakes occur how deep
70km to 300km
deep focus earthquakes occur how deep
300km to 650km
which focus earthquake does the most damage
shallow focus earthquakes
how do you determine the distance to an epicenter
analyze the arrival times of the s and p waves
if s waves arrives soon after p waves
the earthquake must have originated closely to the seismograph station
