answersLogoWhite

0

Earthquake magnitudes are measured using seismometers. Based on the amplitude of the seismic waves, seismologists can make a preliminary estimate of the moment and Richter magnitudes of the earthquake.

For a more accurate estimate of the energy released, seismologists use the moment magnitude scale (MW).

It is calculated from the seismic moment (M0 - which has the unit of dynes/cm =where 1 dyne/cm = 1x10-7 N/m) which is derived based on the elastic moduli of the crust where the earthquake occurred, the length of the slip surface and the cross sectional area of the slip surface as follows:

M0 = G x AFx DF

Where:

G = Shear modulus of the rock mass

AF = Area of the rupture along the fault

DF = average displacement on AF

In order to make the moment magnitude scale (Mw) consistent with older magnitude scales such as the Local Moment (or "Richter") scale the seismic moment (M0) is converted into a logarithmic scale using the following equation:

Mw = 2/3 x log10 x (M0) - 10.7

This ultimately yields a dimensionless number and as such, Moment Magnitude has no units.

Earthquake intensity is measured using the Modified Mercalli Scale. The scale indicates the perceived damage from an earthquake. These parameters are subjective: they depend on the conditions of buildings and the opinions of witnesses. In order to make the measurements more objective, ground accelerations as measured by seismometers are also used to calculate earthquake intensity.
On the Richter scale.
sizemograph

User Avatar

Wiki User

10y ago

What else can I help you with?

Continue Learning about Earth Science

What is the range of mantitude for earthquakes and what sacle is used to measure them?

The magnitude of earthquakes typically ranges from <0 (microearthquakes) to >9 (great earthquakes). The most commonly used scale to measure earthquake magnitude is the Richter Scale or the moment magnitude scale.


How is intensity or energy of earthquakes measured?

The intensity of earthquakes is measured using the Modified Mercalli Intensity (MMI) scale, which assesses the effects of an earthquake at a given location. The energy released during an earthquake is measured using the moment magnitude scale (Mw), which takes into account the seismic moment and rupture length of the earthquake.


What it measured on the Richter scale?

The Richter scale measures the magnitude of seismic waves produced by an earthquake, which provides an estimate of the energy released at the earthquake's source. A higher Richter scale number indicates a stronger earthquake.


Write a note on earthquakes?

Earthquakes are caused by the sudden release of energy in the Earth's crust, leading to the shaking and movement of the ground. They can cause destruction of buildings and infrastructure, as well as trigger landslides and tsunamis. Earthquakes are often measured using the Richter scale to quantify their magnitude.


Why can't you use a Mercalli scale to measure undersea earthquake?

Earthquakescan be measured using the Mercalli Scale, which ranks earthquakes on their effects, such as how they were felt and the damage they caused. Undersea earthquakes can't be measured with this scale because they do not cause this type of damage

Related Questions

How are some earthquakes measured?

they are measured by a Richter scale


Are all the earthquakes in the world measured the same way?

All earthquakes are measured on either the Richter scale or the Mercalli scale.


How is an earthquakes energy measured?

Magnitude


What is measured on the ritchet scale?

The intensity of earthquakes is measured on the Richter Scale.


How are earthquakes impact measured?

Earthquakes are monitered by a device called a Richter Scale.


What intruments scientist use for earthquakes?

Earthquakes are detected and measured using seismometers or seismographs.


What ways are earthquakes measured?

Earthquakes are measured using seismometers that record the seismic waves produced by the shaking of the ground. The two main scales used to measure earthquakes are the Richter scale, which measures the amplitude of seismic waves, and the moment magnitude scale, which considers the total energy released by an earthquake. These scales provide a numerical value called the magnitude to quantify the earthquake's size.


What do you mesure earthquakes in?

an earthquake is measured with a seismograph and its strenght with a Richter scale


How are earthquakes predicted and measured?

Earthquakes are measured using a seismograph. There is no exact science to predicting an earthquake. Scientists can only project the possibility of an earthquake occurring. This is based on measured seismic activity within a specific concentrated zone.


What units are typically used to measure the magnitude of earthquakes?

Earthquakes are typically measured using the Richter scale or the moment magnitude scale, which are both units of measurement for the magnitude of earthquakes.


What are the scales in the magnitude of earthquake?

Large earthquakes (magnitudes greater than 8) are measured using the MMS (moment magnitude) scale. Small and moderate strength earthquakes (those with magnitudes less than 7) are measured using the Richter magnitude scale and earthquakes with magnitudes between 7 and 8 are measured using the Surface Wave magnitude scale.


How is the size of earthquakes measured?

They use a richter scale to measure intensity and magnitude.