What is the difference between a Richter scale and an Mercalli scale?
While the Mercalli scale describes the intensity of an earthquake based on its observed effects, the Richter scale describes the earthquake’s magnitude by measuring the seismic waves that cause the earthquake. The two scales have different applications and measurement techniques.
What is the Mercalli scale GCSE?
The amount of damage caused by an earthquake is measured by the Mercalli Scale. This is a measure of intensity , and changes according to which area you are measuring – damage nearer the epicentre would usually be greater than further away.
What is the Richter scale GCSE?
The Richter scale measures the magnitude of an earthquake (how powerful it is). It is measured using a machine called a seismometer which produces a seismograph. It is logarithmic which means, for example, that an earthquake measuring magnitude 5 is ten times more powerful than an earthquake measuring 4.
How are earthquakes measured GCSE?
All earthquakes are measured on the Richter scale . This scale measures the magnitude of an earthquake. It is measured using a machine called a seismometer , which produces a seismograph. The Richter scale is normally numbered 1-10.
What is the Mercalli scale?
The Mercalli Scale is based on observable earthquake damage. From a scientific standpoint, the magnitude scale is based on seismic records while the Mercalli is based on observable data which can be subjective. Earthquake Magnitude, Energy Release, and Shaking Intensity. Modified Mercalli Intensity Scale.
What does the Mercalli scale not tell you?
Unlike with the Richter scale, the Mercalli scale does not take into account energy of an earthquake directly. Rather, they classify earthquakes by the effects they have (and the destruction they cause). When there is little damage, the scale describes how people felt the earthquake, or how many people felt it.
Why is the Mercalli scale useful?
The Mercalli intensity scale (or more precisely the Modified Mercalli intensity scale) is a scale to measure t of earthquakes. Very often, non-geologists use this scale, because it is easier for people to describe what damage an earthquake caused, than to do calculations to get a value on the Richter scale.
What does the Mercalli scale measure?
The Mercalli Scale is based on observable earthquake damage. From a scientific standpoint, the magnitude scale is based on seismic records while the Mercalli is based on observable data which can be subjective. For example a level I-V on the Mercalli scale would represent a small amount of observable damage.
How is the Richter scale used?
The Richter scale and how it measures earthquake magnitude. The Richter scale calculates an earthquake’s magnitude (size) from the amplitude of the earthquake’s largest seismic wave recorded by a seismograph. Each increase of one unit on the scale represents a 10-fold increase in the magnitude of an earthquake.
How is the Mercalli scale measured?
The Mercalli scale bases its measurement on the observed effects of the earthquake and describes its intensity. The calculation for the Mercalli scale is quantified from the observation of the earthquake’s effect on the earth’s surface. It is also based on the effect on humans, objects, and man-made structures.
What specifically controls the Richter magnitude?
The Richter Magnitude Scale. The magnitude of an earthquake is determined from the logarithm of the amplitude of waves recorded by seismographs. Adjustments are included in the magnitude formula to compensate for the variation in the distance between the various seismographs and the epicenter of the earthquakes.
Why was the Mercalli scale created?
Although numerousintensity scales have been developed over the last several hundred years to evaluate the effects of earthquakes, the one currently used in the United States is the Modified Mercalli (MM) Intensity Scale. It was developed in 1931 by the American seismologists Harry Wood and Frank Neumann.
Which is more objective the Richter scale or the Mercalli scale?
The Richter scale is more objective, but the Mercalli scale is subjective. The Mercalli scale bases its measurement on the observed effects of the earthquake and describes its intensity. It is a linear measurement.
How big is an earthquake on the Richter scale?
A Richter scale is normally numbered 1-10, though there is no upper limit. It is logarithmic which means, for example, that an earthquake measuring magnitude 5 is ten times more powerful than an earthquake measuring 4. Earthquakes measuring 1-2 on the scale happen regularly, and they are so small that people cannot feel them.
Is the Mercalli scale used to measure earthquake strength?
The Mercalli Intensity Scale is only useful for measuring earthquakes in inhabited areas and is not considered particularly scientific, as the experiences of witnesses may vary and the damage caused may not accurately reflect an earthquake’s strength.
How is the intensity scale different from the Richter scale?
The Intensity Scale differs from the Richter Magnitude Scalein that the effects of any one earthquake vary greatly from place to place, so there may be many Intensityvalues (e.g.: IV, VII) measured for the same earthquake.