Vocab
Forces per unit area acting on a material
Stress
Sensitive instruments that can detect the vibrations caused by seismic waves
Crustal rocks fail when stress exceeds the strength of the rocks. The resulting movement occurs along a weak region in the crustal rock called a
What is the result of shaking causing a building’s supporting walls to collapse and the upper floors to fall one on top of the other
Pancaking
The numbers in the Richter scale are determined by the height, called the _________, of the largest seismic wave
amplitude
Wave generated by vertical motions of the seafloor
Tsunami
Often the slowest but most destructive type of wave
Surface Wave
These faults form as a result of horizontal and vertical compression that squeezes rock and creates a shortening of the crust. This causes rock on one side of the fault to be pushed up relative to the other side.
Reverse
What are factors that determine the severity of damage produced by an earthquake.
Earthquake Hazards
The _______ scale is a rating scale of the energy released by an earthquake, taking into account the size of the fault rupture, the amount of movement along the fault, and the rocks’ stiffness
Fracture in rock along which movement occurs
Fault
The second set of waves to be felt during an earthquake
S-Waves
What type of fault occurs when tension causes vertical movement downward along a fault plane.
Normal Fault
Where is the probability of earthquakes much greater than elsewhere on Earth.
Seismic Belts
Which scale uses roman numerals to inidicate the damage and earthquake has casued.
Modified Mercalli Scale
Scale that rates the magnitude of a quake
Richter Scale
These waves squeeze and push rocks in the direction along which the waves are traveling
Primary waves or P-waves
This is caused under conditions of low stress when a material, such as rock, is compressed, bent, or stretched. When the stress is removed, the material returns to its original shape.
Elastic Deformation
Earthquake-_________ ______ along a fault can indicate whether the fault ruptures at regular intervals to generate similar earthquakes
Earthquakes are classified as _______ depending on the location of the focus.
shallow, intermediate, deep
Section of an active fault that has not experienced a significant earthquake for a long time
Seismic Gap
The point on Earth's surface where surface waves originate and then spread out
Epicenter
Explain what type of strain causes strike-slip faults
Shear
In areas with sand that is nearly saturated with water, seismic vibrations can cause the ground to behave like a liquid in a phenomenon called
Soil liquefaction
Seismologists determine the distance to an earthquake’s epicenter by measuring the separation on any seismogram and identifying that same separation time on the
Travel-time Graph