GEOLOGY

Detailed explanation-1: -In theory, the Richter scale has no upper limit, but, in practice, no earthquake has ever been registered on the scale above magnitude 8.6. (That was the Richter magnitude for the Chile earthquake of 1960.

Detailed explanation-2: -The scale was calibrated by defining a magnitude 0 shock as one that produces (at a distance of 100 km (62 mi)) a maximum amplitude of 1 micron (1 µm, or 0.001 millimeters) on a seismogram recorded by a Wood–Anderson torsion seismograph.

Detailed explanation-3: -Numbers for the Richter scale range from 0 to 9, though no real upper limit exists. An earthquake whose magnitude is greater than 4.5 on this scale can cause damage to buildings and other structures; severe earthquakes have magnitudes greater than 7.

Detailed explanation-4: -The first widely-used method, the Richter scale, was developed by Charles F. Richter in 1934. It used a formula based on the amplitude of the largest wave recorded on a specific type of seismometer and the distance between the earthquake and the seismometer.

Detailed explanation-5: -The idea of a logarithmic earthquake magnitude scale was first developed by Charles Richter in the 1930’s for measuring the size of earthquakes occurring in southern California using relatively high-frequency data from nearby seismograph stations.