Earthquake magnitude, intensity, energy, and acceleration

Abstract

This supersedes Paper 1 (Gutenberg and Richter, 1942). Additional data are presented. Revisions involving intensity and acceleration are minor. The equation log a = I/3 − 1/2 is retained. The magnitude-energy relation is revised as follows: (20) log ⁡ E = 9.4 + 2.14 M − 0.054 M 2 A numerical equivalent, for M from 1 to 8.6, is (21) log ⁡ E = 9.1 + 1.75 M + log ⁡ ( 9 − M ) Equation (20) is based on (7) log ⁡ ( A 0 / T 0 ) = − 0.76 + 0.91 M − 0.027 M 2 applying at an assumed point epicenter. Eq. (7) is derived empirically from readings of torsion seismometers and USCGS accelerographs. Amplitudes at the USCGS locations have been divided by an average factor of 2 1/2 to compensate for difference in ground; previously this correction was neglected, and log E was overestimated by 0.8. The terms M2 are due partly to the response of the torsion seismometers as affected by increase of ground period with M, partly to the use of surface waves to determine M. If MS results from surface waves, MB from body waves, approximately (27) M S − M B = 0.4 ( M S − 7 ) It appears that MB corresponds more closely to the magnitude scale determined for local earthquakes. A complete revision of the magnitude scale, with appropriate tables and charts, is in preparation. This will probably be based on A/T rather than amplitudes.

Earthquake‐Spawning Faults in the Seoul Metropolitan Area and Their Seismic Implications

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Statistical bounds on how induced seismicity stops

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Comparative Analysis of Neogeodynamics of the Baltic Syneclise and the Northern Slope of the Voronezh Anteclise A

“…Отметим, что для каждого землетрясения, произошедшего на территории Воронежского массива, указан его энергетический класс. Для того чтобы объединить результаты этого сейсмического мониторинга с данными [USGS Earth-quake…, 2019;Seismic Catalogues…, 2020;Garetsky, Nesmeyanov, 2009], нами проведен пересчет энергетического класса в энергию, а затем в магнитуду по следующим формулам: K s =lgE; lgE=4.8+1.5M s , lgE=-1.2+2.4m b (предложена Рихтером) и m b =2.3+0.63M s (зависимость Гутенберга -Рихтера) [Gutenberg, Richter, 1956;Storcheus, 2008Storcheus, , 2011Zakharov, Smirnov, 2016] При проведении компьютерного моделирования новейшей геодинамики использовались ЦМР, данные о глубине поверхности фундамента Балтийской синеклизы [Zakashansky, 1963;Jubitz, 1983], батиметрическая карта Балтийского моря [Rudenko, Ryazheva, 2004], физико-механические параметры среды (коэффициенты Пуассона и внутреннего трения), информация о конфигурации достоверных и предполагаемых активных разломов. Моделирование выполнено в программе Reservoir Modeling System (RMS) 2013 компании «ROXAR».…”