Richter scale - A 75-year-old system to measure quake

Richter was a seismologist at the California Institute of Technology (Caltech) from 1927 until his retirement as professor emeritus in 1970.

According to the institute, Richter invented the Richter Scale in 1935 with collaborator Beno Gutenberg.

He authored two standard textbooks on seismology.

In 1980, Richter said the scale was established as the seismological lab needed a proper tool to keep track of the magnitudes of the 200 to 300 earthquakes that were studied annually.

Richter died in 1985.