Why might an earth quake have more than one intensity value?

Answer 1

Yes. The Mercalli intensity scale measures the effect of the earthquake on people and structures, and the intensity value will differ depending on how far you are from the epicenter.

For instance, a 5.5 magnitude earthquake may be damaging (intensity VII) around the epicenter, but 300 miles away it may be barely felt (intensity II).

The mercalli scale measures the intensity of an earthquake, where the Richter scale measures the magnitude.

Also you have to consider where the earthquake occurred. you can have a 9.0 quake in the middle of the Australian outback but there is hardly anybody there so you would have a low mercalli scale reading. If you had that same quake in San Francisco then you are going to have a seriously high number on the mercalli scale

Answer 2

The Modified Mercalli scale assigns a value to an earthquake from I to XII depending on it's intensity, with I being the lowest (only recorded by seismometers, not felt by humans) and XII being the highest (representing total destruction of all buildings).

Mercalli values are derived from a number of sources including witness reports of the perceived ground shaking in their location, the damage to structures and also measurements of the ground accelerations from seismometers (included to attempt to reduce the subjectivity of the scale due to it's reliance on human witnesses).

Answer 3

It depends what you mean by the MMS scale. This could either be the Moment Magnitude scale or the Modified Mercalli scale.

The Modified Mercalli scale was designed to measure the intensity of an earthquake whereas the Richter scale was used to measure the magnitude of an earthquake.

Magnitude is the amount of energy released by an earthquake and is the same no matter where it is measured. Intensity is a measure of the severity of ground shaking and damage caused by an earthquake at a specific point and so can vary depending on the specific local ground conditions and the distance from the epicentre where it is measures.

The Moment Magnitude scale like the Richter scale is used to find the amount of energy released in an earthquake. However they use different methods to calculate this value. Using Richter's technique, the magnitude is assessed by the amplitude of seismic waves as measured by a seismometer (after applying a correction based on the distance of the seismometer station from the epicentre). The Moment magnitude scale is based on deriving the "seismic moment" of the earthquake. This is calculated based on the cross sectional area of the fault surface that slipped during the earthquake, the size of the fault displacement and the elastic properties of the rock mass surrounding the fault. This difference in measuring techniques normally accounts for the difference in Moment and Richter magnitudes for a given earthquake.

Answer 4

It depends what you mean by the MMS scale. This could either be the Moment Magnitude scale or the Modified Mercalli scale.



The Modified Mercalli scale was designed to measure the intensity of an earthquake whereas the Richter scale was used to measure the magnitude of an earthquake.


Magnitude is the amount of energy released by an earthquake and is the same no matter where it is measured. Intensity is a measure of the severity of ground shaking and damage caused by an earthquake at a specific point and so can vary depending on the specific local ground conditions and the distance from the epicentre where it is measures.



The Moment Magnitude scale like the Richter scale is used to find the amount of energy released in an earthquake. However they use different methods to calculate this value. Using Richter's technique, the magnitude is assessed by the amplitude of seismic waves as measured by a seismometer (after applying a correction based on the distance of the seismometer station from the epicentre). The Moment magnitude scale is based on deriving the "seismic moment" of the earthquake. This is calculated based on the cross sectional area of the fault surface that slipped during the earthquake, the size of the fault displacement and the elastic properties of the rock mass surrounding the fault. This difference in measuring techniques normally accounts for the difference in Moment and Richter magnitudes for a given earthquake.

Answer 5

Because an earthquakes magnitude is different from its intensity. Intensity measures the affects of an earthquake at earths surface. Magnitude measures how much energy is released by an earthquake.

Answer 6

Earthquakes can generate multiple intensity values because the shaking and resulting damage can vary in strength and duration across different locations. Factors such as distance from the epicenter, local geology, and building construction can all influence the intensity experienced in a particular area. This variability is why different locations affected by the same earthquake can report different intensity values.

Answer 7

An earthquake might have more than one intensity value because there can be an aftershock.

Answer 8

It might have an aftershock perhaps? :3