GEOLOGY

Detailed explanation-1: -Sometimes earthquakes are referred to by the maximum intensity they produce. In the United States, we use the Modified Mercalli (MMI) Scale. The Mercalli Scale is based on observable earthquake damage.

Detailed explanation-2: -The highest rating, a XII, is applied to earthquakes in which structures are destroyed, the ground is cracked and other natural disasters, such as landslides or tsunamis, are initiated.

Detailed explanation-3: -Note: The Modified Mercalli scale is designed to describe the effects of an earthquake, at a given place, on natural features, on industrial installations and on human beings. The intensity differs from the magnitude which is related to the energy released by an earthquake.

Detailed explanation-4: -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.

Detailed explanation-5: -The Modified Mercalli scale measures the earthquake’s effect on people, property and ground damage. Roman numerals are used to rate the intensity and damage. An earthquake may have a different intensity rating at different locations. Damage is usually lessened with distance from the earthquake’s epicenter.