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Minimal recorded earthquakes

Richter, C. F. and Nordquist, J. M. (1948) Minimal recorded earthquakes. Bulletin of the Seismological Society of America, 38 (4). pp. 257-261. ISSN 0037-1106. doi:10.1785/BSSA0380040257.

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The magnitude of an earthquake was originally defined (Richter, 1935) as the common logarithm of the maximum displacement, expressed in microns, of the trace written by a standard torsion seismometer at an epicentral distance of 100 kilometers. When this trace amplitude is one micron the magnitude is accordingly zero.

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Additional Information:Copyright © 1948, by the Seismological Society of America. Manuscript received for publication March 3, 1948.
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Caltech Division of Geological Sciences447
Issue or Number:4
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:47736
Deposited By: George Porter
Deposited On:31 Jul 2014 22:18
Last Modified:11 Feb 2022 16:11

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