CHARLES RICHTER (1900-1985) INTERVIEWED BY ANN SCHEID February 15-September 1, 1978 ARCHIVES CALIFORNIA INSTITUTE OF TECHNOLOGY Pasadena, California Subject area Seismology Abstract Interview in 1978 with Charles F. Richter, professor of seismology emeritus, in the Division of Geological and Planetary Sciences. A pioneer in seismology and active in the seismology and earthquake engineering fields for over fifty years, Richter’s name is known for the earthquake magnitude scale he developed in the 1930s for local earthquakes. Richter received his PhD from Caltech in 1928. In 1937 he joined the Caltech faculty and worked alongside Harry Wood in the Seismological Laboratory, which that year was transferred to Caltech from the Carnegie Institution of Washington and was situated in the San Rafael area of Pasadena. The interview covers a wide range of topics, including his graduate student years at Caltech, then headed by Robert A. Millikan; recollections of Harry Wood, Beno Gutenberg, and Hugo Benioff and their work in the early years of the Seismological Laboratory; the prospects for earthquake prediction; the role of the Bikini atomic tests in studies of the propagation of seismic waves; the tectonics of Japan; the importance of earthquake engineering; his consulting work with the L.A. Dept. of Water and Power; and his views on latter-day developments in the geology division and at Caltech. http://resolver.caltech.edu/CaltechOH:OH_Richter_C Administrative information Access The interview is unrestricted. Copyright Copyright has been assigned to the California Institute of Technology © 1979. All requests for permission to publish or quote from the transcript must be submitted in writing to the University Archivist. Preferred citation Richter, Charles. Interview by Ann Scheid. Pasadena, California, February 15- September 1, 1978. Oral History Project, California Institute of Technology Archives. Retrieved [supply date of retrieval] from the World Wide Web: http://resolver.caltech.edu/CaltechOH:OH_Richter_C Contact information Archives, California Institute of Technology Mail Code 015A-74 Pasadena, CA 91125 Phone: (626)395-2704 Fax: (626)793-8756 Email: [email protected] Graphics and content © California Institute of Technology. http://resolver.caltech.edu/CaltechOH:OH_Richter_C Reprinted from BULLETIN OF THE SEISMOLOGICAL SociETY OF AMERICA Vol. 25, No. 1, January, 1935 • AN INSTRU MENTAL EARTHQUAKE MAGNITUDE SCALE* BY CHARLES F. RICHTER In the course of historical or statistical study of earthquakes in any given region it is frequently desirable to have a scale for rating these shocks in terms of their original energy, independently of the effects which may be produced at any particular point of observation. On the suggestion of Mr. H . 0 . Wood, it is here proposed to refer to such a scale as a "magnitude" scale. This terminology is offered in distinction from the name "intensity" scale, now in general use for such scales as the Rossi-Forel and Mercalli-Cancani scales, which refer primarily to the local intensity of shock manifestation. The writer is not aware of any previous approach to this problem along the course taken in this paper, except for the work of Wadati cited below. Total original energies have been calculated ·for ·a number of shocks, using seis.mometric an'd other data; but such a procedure is prac­ ticable only for a limited number of cases, whereas it is desired to apply a magnitude scale to all or nearly all of the shocks occurrii1g. Mi·. Maxwell vV. Allen states that he has for some time employed an arbitrary scale for rating large earthquakes, based on the amplitudes of earth motion calculated from the. reports of distant stations. This labori­ ous procedure is not far removed in principle from that adopted in the following discussion. Doubtless it has also occunred to others, but has failed of general application because of its paucity of dependable results. In the absence of any accepted magnitude scale, earthquakes have oc­ casionally been compared in terms of the intensity on the Rossi-Forel or some similar scale, as manifested near the epicenter. Even when reliable information is obtainable, this method is obviously exposed to uncertain­ ties arising from variations in the character of the ground, the depth of the focus, and other circumstances not easily allowed for. In a region such as Southern California, where a large proportion of the shocks occur *[Received for publication June 17, 1934.] Charles Richter’s original paper, with signature, from 1935 on the creation of the earthquake magnitude scale that today bears his name. http://resolver.caltech.edu/CaltechOH:OH_Richter_C California Institute of Technology Oral History Project Interview with Charles F. Richter by Ann Scheid Pasadena, California Caltech Archives, 1979 Copyright e 1979 by the California Institute of Technology http://resolver.caltech .edu/CaltechO H :0 H_Richter_ C TABLE OF CON~ENTS Interview with Charles F. Richter Session 1 1-36 Family background; emigration from Germany to ~ew York, and eventually to Los Angeles (in 1909); grandfather's business i~ Ohio; attending USC preparatory school; influence of mathe­ matics irJ.structor, Hugh 1Villett; early interest in astronoL'ly (first scientific interest); college--freshman year at USC and transfer to Stanford; return to L.A. and odd jobs for three years. Hearing of Millikan's lect'J.res at ':L'hroop and being attracted to graduate study; studying with Paul Epstein; thesis problem on spinning electron suggested by letter from Ehrenfest to Millikan; Schrodinger; development of quantum Tiechanics; H.P. Robertson; narriage to Lillian Brand; Clinton Judy's informal discussion meetings on literary topics; fellow students (W. Houston, C. Eckart, I. Bowen, C. Millikan); Harry Bateman. Job offer from Seismological Lab and move there (1927); staff at Lab; state of seismology iL ~wenties; international data sharing; ~ong Beach earthquake (1933); support for seismology from insurance companies; ·.1se of portable i~stallations for measuring quakes; 1929 conference to evaluate progress of seis­ mology prograTI; invitation to Beno Gutenberg to join Lab staff; Gutenberg's work; Einstein; develop~ng Richter Magnitude Scale; recent progress on detection of micro-eart~quakes. Session 2 37-73 Great-grandfat~er 1 s political activities in Germany and emigration to New York; grandfather's influence on education; R.C. Tolman; E.T. Bell; Epstein's standards of excellence; H.P. Robertson; caTiping expeditions with Lorquin Natural History Cl·.1b; establishment of Seismological Lab funded by Carnegie Institution; Earry Wood, director of Lab; negative feelings about teaching, especially at first; war work on mathematical problems related to rocket project; subsequent war-related seismology OL geologically active areas in Pacific; change of administration froTI Millikan to DuBridge; problems with student body after war; beginning of interview system for admissions. Gradua~e students in seismology; Balches' donations to Seismology Lab after Caltech took over from Carnegie; contacts with Associates; contacts with press; quality of reporting abou~ earthquakes in popular press; changes in Institute after war; increasing faculty contacts with industry after the war; problems involved with recording atomic bomb tests; repercussions at Caltech of anti-communism of fifties; Lee DuBridge; trip to Japan (1959); exchange of seismographic information with Japanese. http://resolver. caltech. edu/CaltechO H: 0 H_Richter_ C TABLE OF CONTENTS continued Session 3 74-109 Safety of tall buildings; problems of earthquake prediction; Chinese efforts at prediction; prediction by Dr. Whitcomb at Caltech; earthquake swarms as possible prediction tool; triggering earthquakes artificially; characterizing faults worldwide; possibility of setting up instruments in underdeveloped nations; history of government agencies responsible for earthquake measurements--Geological Survey, Weather Bureau, and Coast and Geodetic Survey; role of insurance companies in study of strong motion; Caltech Earthquake Research Associates; attempts of real estate interests to modify earthquake safety regulations. R.C. Tolman; scientific discussions at Faculty Club lunch table; translating paper for von Karman; Beno Gutenberg; Harold Jeffreys; collaborating with Gutenberg on seismic waves and seismicity of the earth; Hugo Benioff. Session 4 110-129 State Geology Board for certifying geologists; consulting work after retirement (Lindvall, Richter and Associates), primarily on safety of dams and reservoirs; Chester Stock and paleontology at Caltech; John Peter Buwalda; anecdote about Harry Bateman; response to changes in Caltech's image as small research institution to more diversified school; addition of economics to humanities division; controversy over admission of women; publishing data on seismic waves caused by bomb tests. Session 5 130-155 Appointment to Seismological Laboratory as research assistant; gathering detailed information about seismic activity of Southern California; Benioff's work on instrumentation; working with Harry Wood; Wood's earlier work in history of California earthquakes; Maxwell Allen; relationship between Carnegie Institution and Seismo­ logical Lab; 1929 conference to evaluate Lab's progress; Wood's modification of Mercalli intensity scale; collecting data to make it possible to locate earthquake epicenters; Wood and Anderson collaboration on torsion seismometer; effect of Long Beach earthquake on Seismo Lab's activities; trip