science quiest

a hypothesis that sates that sections of active faults that have had relatively few earthquakes are likely to be the sites of strong earthquakes in the future

Gap hypothesis

Seismographs

Instruments located at or near the surface of the Earth that record seismic waves.

The greater the seismic activity, the higher the __________________

earthquake-hazard level

the point on Earth's surface directly above an earthquake's starting point

epicenter

The areas along a fault where relatively few earthquakes have occured

seismic gaps

When the waves reach a seismograph, the seismograph creates a

seismogram

Seismologists also use ________ to find an earthquake's epicenter.

seismograms

Seismograms can be used not only to determine and earthquake's epicenter and its start time, but also to find out an earthquake's ________

strength

A measure of the strength of an earthquake

magnitude

a measurement of how likely an area is to have damaging earthquakes in the future

Earthquake hazard

Each time the magnitude increases by one unit, the measured ground motion becomes ____ times larger.

10

Seismologists in the U.S. use this to measure earthquake intensity

Modified Mercalli Intensity Scale

The scale is a numerical scale that uses Roman numerals from I to XII to describe increasing increasing earthquake intensity levels.

Modified Mercalli Intensity Scale

Seismologists find an earthquake's start time by comparing _________ and noticing the differences in arrival times of_____________________

Seismograms, P waves and S waves

Each time the magnitude increases by one unit, the measured ground motion becomes 10 times larger.

The Richter Scale

measures the ground motion from an earthquake and adjusts for distance to find its strength.

The Richter Scale

The simplest method by which seismologists find an earthquake's epicenter

The S-P time method

Explain the difference between the Richter Scale and the Mercalli Modified Intensity Scale?

There are many differences between the Mercalli Scale and the Richter Scale. The Richter Scale measures the ground motion from an earthquake and adjusts for distance to find its strength. The data is collected using a logarithmic formula using high-frequency data collected from seismograph stations. Each time the magnitude increases by one unit, the measured ground motion becomes 10 times larger. The Modified Mercalli Intensity Scale measures the degree to which an earthquake is felt by people and the amount of damage caused by the earthquake. One differences is that the scale is a numerical scale that uses Roman numerals from I to XII to describe increasing increasing earthquake intensity levels. After the occurrence of an earthquake, scientists questionnaire citizens in the disturbed area requesting information about how intense the earthquake felt to them. After the questionnaire, the information furnished by other sources are used to assign an intensity within the felt area. I being the lowest intensity level and XII being the highest. Another difference is the way the scales describe the earthquakes. The Mercalli Scale describes the intensity of an earthquake bases on its observed effects, while the Richter scale describes the earths magnitude by measuring the seismic waves the cause the earthquakes. The two scales also have different measurement techniques. Lastly, the Mercalli Scale measures linear (in a straight line), but the Richter Scale measures non linear. This means that the Mercalli Scale uses observation and comes out linear when the graphed information comes out non linear. Although they are both seismographs, there are many differences between the Richter Scale and Mercalli Modified Intensity Scale.

the point inside the earth where an earthquake begins

focus

A measure of the degree to which an earthquake is felt by people and the amount of damage caused by the earthquake.

intensity.

An areas earthquake-hazard level is determined by...

past and present seismic activity