Richter, Charles, 1900-1985

Seismologist. Died 1985.

Richter (1900-1985). Physicist (geophysics, seismology) best known as the seismologist who developed the magnitude scale that bears his name; received his Ph. D. in physics from Caltech, where he remained as a member of the faculty until 1970.

Biography

Charles Francis Richter was born April 26, 1900 on a farm near Hamilton, Ohio. His parents divorced when he was young and his mother resumed her maiden name, Richter. In 1909 the family moved to Los Angeles. Richter entered the University of Southern California (USC) at the age of sixteen and after one year transferred to Stanford, where he received his bachelor's degree in physics in 1920. He completed his schooling at Caltech, earning a PhD in theoretical physics in 1928.

Richter had planned to make his career in astronomy but when Robert A. Millikan asked him to become a research assistant at the Seismology Laboratory, sponsored by the Carnegie Institution of Washington, he accepted the position. Once involved, he believed that he was associated with an unexploited field and that he was getting in on the ground floor. Richter's entire career was spent at Caltech, except for 1959-1960 when he was a Fulbright scholar in Japan. He became assistant professor in 1937, associate professor in 1947, full professor in 1952 and emeritus in 1970.

A pioneer in seismology and active in seismological and earthquake engineering fields for over fifty years, Richter became known worldwide for the earthquake scale which he helped develop and which today bears his name. The Mercalli Scale, the most commonly used scale prior to Richter's, measured an earthquake's intensity at the point of the seismometers and not at the origin of the quake. What was needed was a means of ranking earthquakes measuring magnitude rather than intensity. At the suggestion of Beno Gutenberg, Caltech's distinguished professor of geophysics, Richter devised a scale in logarithmic terms. He developed a means of measuring an earthquake's strength at three or more points so that the point of origin could be determined. By comparing distance with recorded strength, the intensity of the tremor at the epicenter could be estimated.

Richter was an important influence on the education of most of today's seismologists. His book, Elementary Seismology, has been the standard textbook for beginning seismology students. He was co-author with Gutenberg of Seismicity of the Earth and author or co-author of over 200 scientific papers. A researcher, teacher and advisor, Richter made major contributions to the advancement of the science of seismology and to the public's understanding of earthquakes.

In 1971 he helped start the consulting firm of Lindvall, Richter and Associates that offered seismic evaluations of structures. He remained active in the firm following retirement from Caltech.

Among his numerous honors and awards was the medal of the Seismological Society of America. Richter held the presidency of SSA, was a fellow of the American Academy of Arts and Sciences, member of Sigma Xi and had the honor of being present at the dedication of the Charles F. Richter Seismology Laboratory at the University of California, Santa Cruz.