# What are the similarities and differences between the Richter and moment magnitude scales?

## What are the similarities and differences between the Richter and moment magnitude scales?

Moment magnitude estimates are about the same as Richter magnitudes for small to large earthquakes. But only the moment magnitude scale is capable of measuring M8 (read “magnitude 8”) and greater events accurately. Magnitudes are based on a logarithmic scale (base 10).

## What do Mercalli and Richter scale provide and measure?

The Richter scale measures the magnitude of earthquakes, and the Mercalli scale measures their intensity.

What are the similarities of intensity and magnitude?

Magnitude measures the energy released at the source of the earthquake. Magnitude is determined from measurements on seismographs. Intensity measures the strength of shaking produced by the earthquake at a certain location. Intensity is determined from effects on people, human structures, and the natural environment.

What is the difference between Richter scale and intensity scale?

The Richter Magnitude Scale measures the amount of seismic energy released by an earthquake. Intensity is how well you receive the signal, which can depend on your distance from the energy source, the local conditions, and the pathway the signal has to take to reach you.

### Why is the moment magnitude scale used today and basically replaces the Richter scale?

An earthquake has one magnitude unit. The magnitude does not depend on the location where measurement is made. Since 1970, the Moment Magnitude Scale has been used because it supports earthquake detection all over the Earth.

### What makes the moment magnitude scale more accurate than the Richter scale?

The main reason why the moment magnitude scale is the most reliable method of calculating the relative size of large earthquakes is that its underlying calculation process avoids the problem of magnitude saturation, because it is based on measurements of an earthquake’s total energy.

How does the Mercalli scale measure?

The Mercalli Intensity Scale measures the intensity of an earthquake by observing its effect on people, the environment and the earthâ€™s surface.

What is the used of Mercalli scale and Rossi Forel scale?

Intensity scales, like the Modified Mercalli Scale and the Rossi-Forel scale, measure the amount of shaking at a particular location. An earthquake causes many different intensities of shaking in the area of the epicenter where it occurs. In the United States, we use the Modified Mercalli (MMI) Scale.

#### How does the Mercalli scale work?

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.

#### How is the Mercalli scale used?

The Mercalli Intensity Scale measures the intensity of an earthquake by observing its effect on people, the environment and the earth’s surface. The Richter Scale measures the energy released by an earthquake using a seismograph.

What is the scale of the Richter scale?

The Richter scale is a base-10 logarithmic scale, meaning that each order of magnitude is 10 times more intensive than the last one. In other words, a two is 10 times more intense than a one and a three is 100 times greater. In the case of the Richter scale, the increase is in wave amplitude.