EARTH SCIENCE
EARTHQUAKES
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
It is a measure of the amount of energy released by an earthquake, which is derived from the amount of displacement that occurs along the fault zone, and is more precise than the Richter scale.
|
|
|
It measures the height of the largest seismic wave recorded on the seismogram, and is more precise than the Mercalli Scale.
|
|
|
It rates earthquake intensity in terms of the damage caused to areas affected by the quake, and is more precise than the Richter Scale.
|
|
|
It is momentous! MOMENTOUS, I SAY!!!
|
Detailed explanation-1: -This is because, a moment magnitude scale measures the intensity of an earthquake based on the amount of displacement occurred along a fault zone while richter scale measures the intensity based on the amount of ground movement at a given point.
Detailed explanation-2: -The moment magnitude scale is based on the total moment release of the earthquake. Moment is a product of the distance a fault moved and the force required to move it. It is derived from modeling recordings of the earthquake at multiple stations.
Detailed explanation-3: -In particular, for very large earthquakes, moment magnitude gives the most reliable estimate of earthquake size. Moment is a physical quantity proportional to the slip on the fault multiplied by the area of the fault surface that slips; it is related to the total energy released in the earthquake.
Detailed explanation-4: -Seismic moment is measured in units of Newton meters (N·m) or Joules, or (in the older CGS system) dyne-centimeters (dyn-cm). The first calculation of an earthquake’s seismic moment from its seismic waves was by Keiiti Aki for the 1964 Niigata earthquake.
Detailed explanation-5: -Richter Scale is mostly effective for regional earthquakes no greater than M5. Moment Magnitude is more effective for large earthquakes Moment Magnitude uses more variables to calculate the energy released using seismic moment. Seismic moment combines the seismic energy with offset on the fault and rigidity of rock.