196:
32:
79:
1442:
1334:
1553:
874:
1018:
waves, namely shallow earthquakes at distances >100 km from the seismic receiver, corrections must be added to the computed value to compensate for epicenters deeper than 50 km or less than 20° from the receiver.
1022:
For official use by the
Chinese government, the two horizontal displacements must be measured at the same time or within 1/8 of a period; if the two displacements have different periods, a weighted sum must be used:
982:
1125:
1223:
1342:
1234:
656:. Surface waves with a period near 20 s generally produce the largest amplitudes on a standard long-period seismograph, and so the amplitude of these waves is used to determine
1453:
1012:
776:
749:
708:
681:
654:
627:
547:
792:
1876:
1911:
1652:
987:
Several versions of this equation were derived throughout the 20th century, with minor variations in the constant values. Since the original form of
1791:
1679:
402:
1988:
917:
1029:
1653:
XU Shaokui, LU Yuanzhong, GUO Lucan, CHEN Shanpei, XU Zhonghuai, XIAO Chengye, FENG Yijun (许绍燮、陆远忠、郭履灿、陈培善、许忠淮、肖承邺、冯义钧) (1999-04-26).
602:
to develop magnitude scales based on teleseismic observations of earthquakes. Two scales were developed, one based on surface waves,
143:
1846:
115:
1973:
1896:
96:
122:
1983:
1978:
1881:
1712:
504:
1654:
1906:
129:
2014:
1901:
162:
111:
1657:(in Chinese). General Administration of Quality Supervision, Inspection, and Quarantine of P.R.C. Archived from
252:
100:
1932:
1891:
579:
433:
1839:
1437:{\displaystyle M_{s}=\log _{10}\left({\frac {A_{\text{max}}}{T}}\right)+1.73\cdot \log _{10}(\Delta )+3.27}
1329:{\displaystyle M_{s}=\log _{10}\left({\frac {A_{\text{max}}}{T}}\right)+1.54\cdot \log _{10}(\Delta )+3.53}
1768:
1548:{\displaystyle M_{s}=\log _{10}\left({\frac {A_{\text{max}}}{T}}\right)-6.2\cdot \log _{10}(\Delta )+20.6}
1176:
1886:
300:
53:
715:
William L. Ellsworth, The San
Andreas Fault System, California (USGS Professional Paper 1515), 1990–1991
497:
478:
438:
44:
1696:
Bath, M (1966). "Earthquake energy and magnitude". In Ahrens, L. H.; Press, F.; Runcorn, S. (eds.).
136:
1855:
1564:
381:
376:
20:
1832:
721:
571:
227:
89:
49:
1942:
443:
410:
551:
1993:
1163:
880:
567:
466:
394:
267:
247:
242:
237:
1585:
869:{\displaystyle M_{s}=\log _{10}\left({\frac {A}{T}}\right)_{\text{max}}+\sigma (\Delta )\,,}
566:
that travel along the uppermost layers of the Earth. This magnitude scale is related to the
1724:
1622:
990:
754:
727:
686:
659:
632:
605:
525:
490:
473:
428:
262:
179:
8:
1927:
1769:
CHEN Junjie, CHI Tianfeng, WANG Junliang, CHI Zhencai (陈俊杰, 迟天峰, 王军亮, 迟振才) (2002-01-01).
904:
328:
205:
1728:
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1770:
1740:
305:
272:
232:
1785:
1744:
1673:
1634:
1732:
1630:
1613:
Kanamori, Hiroo (April 1983). "Magnitude scale and quantification of earthquakes".
892:
277:
1162:
Vladimír Tobyáš and
Reinhard Mittag proposed to relate surface wave magnitude to
599:
295:
257:
1810:
195:
1658:
908:
595:
575:
1228:
Other formulas include three revised formulae proposed by CHEN Junjie et al.:
2008:
1937:
563:
1952:
1824:
343:
720:
Recorded magnitudes of earthquakes through the mid 20th century, commonly
31:
1015:
371:
338:
1748:
1736:
888:
884:
559:
555:
453:
333:
222:
187:
977:{\displaystyle \sigma (\Delta )=1.66\cdot \log _{10}(\Delta )+3.5\,.}
323:
217:
212:
1811:"The San Andreas Fault System, California (Professional Paper 1515)"
78:
1710:
594:
The successful development of the local-magnitude scale encouraged
448:
1120:{\displaystyle T={\frac {T_{N}A_{N}+T_{E}A_{E}}{A_{N}+A_{E}}}\,,}
583:
896:
353:
348:
1713:"Local magnitude, surface wave magnitude and seismic energy"
1773:(in Chinese). Journal of Seismological Research (《地震研究》)
578:
throughout the 1940s and 1950s. It is currently used in
1877:
Central
Weather Administration seismic intensity scale
1771:"Study of Surface Wave Magnitude in China (中国面波震级研究)"
1456:
1345:
1237:
1179:
1032:
993:
920:
795:
757:
730:
689:
662:
635:
608:
528:
1583:
786:
The formula to calculate surface wave magnitude is:
103:. Unsourced material may be challenged and removed.
1711:Vladimír Tobyáš and Reinhard Mittag (1991-02-06).
1547:
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1328:
1217:
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770:
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675:
648:
621:
574:in 1935, with modifications from both Richter and
541:
1808:
2006:
1655:"Specifications on Seismic Magnitudes (地震震级的规定)"
1648:
1646:
1644:
1840:
1704:
683:, using an equation similar to that used for
498:
1854:
1790:: CS1 maint: multiple names: authors list (
1678:: CS1 maint: multiple names: authors list (
1882:Environmental Seismic Intensity scale (ESI)
1641:
1907:PHIVOLCS Earthquake Intensity Scale (PEIS)
1847:
1833:
1608:
1606:
505:
491:
1113:
970:
862:
163:Learn how and when to remove this message
1612:
1577:
1134:is the north–south displacement in μm, A
887:of the two horizontal displacements) in
1603:
1570:
2007:
1691:
1689:
1138:is the east–west displacement in μm, T
19:For a review of magnitude scales, see
1828:
1695:
1218:{\displaystyle M_{s}=-3.2+1.45M_{L}}
101:adding citations to reliable sources
72:
25:
1700:. Pergamon Press. pp. 115–165.
1686:
13:
1698:Physics and Chemistry of the Earth
1533:
1422:
1314:
958:
927:
856:
14:
2026:
1887:European Macroseismic Scale (EMS)
1802:
562:. It is based on measurements of
1157:
1150:is the period corresponding to A
1142:is the period corresponding to A
590:) for categorising earthquakes.
194:
77:
30:
1938:Local magnitude (Richter scale)
1897:Medvedev–Sponheuer–Karnik (MSK)
1809:Robert E. Wallace, ed. (1991).
1717:Studia Geophysica et Geodaetica
1590:) AND BODY-WAVE MAGNITUDE (mb)"
88:needs additional citations for
1979:Mercalli–Cancani–Sieberg (MCS)
1762:
1536:
1530:
1425:
1419:
1317:
1311:
961:
955:
930:
924:
859:
853:
1:
1584:William L. Ellsworth (1991).
781:
1635:10.1016/0040-1951(83)90273-1
16:Earthquake measurement scale
7:
1558:
558:to describe the size of an
43:to comply with Knowledge's
10:
2031:
1984:Mercalli–Wood–Neuman (MWN)
1586:"SURFACE-WAVE MAGNITUDE (M
580:People's Republic of China
403:Coordinating Committee for
18:
1966:
1920:
1869:
1862:
1014:was derived for use with
891:, T is the corresponding
629:, and one on body waves,
434:Adams–Williamson equation
2015:Seismic magnitude scales
1856:Seismic magnitude scales
1565:Seismic magnitude scales
382:Seismic intensity scales
377:Seismic magnitude scales
112:"Surface-wave magnitude"
56:may contain suggestions.
41:may need to be rewritten
21:seismic magnitude scales
879:where A is the maximum
572:Charles Francis Richter
47:, as explained on Talk.
1948:Surface-wave magnitude
1902:Modified Mercalli (MM)
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564:Rayleigh surface waves
550:) scale is one of the
543:
519:surface wave magnitude
444:Earthquake engineering
1550:
1439:
1331:
1220:
1164:local magnitude scale
1122:
1009:
1007:{\displaystyle M_{s}}
979:
903:2 seconds), Δ is the
881:particle displacement
871:
773:
771:{\displaystyle M_{L}}
746:
744:{\displaystyle M_{s}}
722:attributed to Richter
705:
703:{\displaystyle M_{L}}
678:
676:{\displaystyle M_{s}}
651:
649:{\displaystyle M_{b}}
624:
622:{\displaystyle M_{s}}
592:
568:local magnitude scale
544:
542:{\displaystyle M_{s}}
467:Earth Sciences Portal
439:Flinn–Engdahl regions
405:Earthquake Prediction
1571:Notes and references
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687:
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633:
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526:
429:Shear wave splitting
97:improve this article
1928:Body-wave magnitude
1729:1991StGG...35..354T
1627:1983Tectp..93..185K
905:epicentral distance
329:Epicentral distance
1933:Duration magnitude
1737:10.1007/BF01613981
1545:
1434:
1326:
1215:
1117:
1004:
974:
883:in surface waves (
866:
768:
741:
724:, could be either
700:
673:
646:
619:
539:
306:Induced seismicity
253:Remotely triggered
2002:
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1967:Historical scales
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1961:
1912:Shindo (Japanese)
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584:national standard
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45:quality standards
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1943:Moment magnitude
1921:Magnitude scales
1870:Intensity scales
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1621:(3–4): 185–199.
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1863:Modern scales
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1751:on 2013-01-04
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153:November 2017
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114: –
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108:Find sources:
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86:This article
84:
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62:November 2017
55:
51:
46:
42:
39:This article
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1953:Energy class
1947:
1815:. Retrieved
1775:. Retrieved
1764:
1753:. Retrieved
1749:the original
1720:
1716:
1706:
1697:
1663:. Retrieved
1659:the original
1618:
1614:
1594:. Retrieved
1579:
1446:
1227:
1161:
1129:
1021:
986:
899:(usually 20
878:
785:
719:
593:
587:
570:proposed by
522:
518:
516:
423:Other topics
228:Blind thrust
159:
150:
140:
133:
126:
119:
107:
95:Please help
90:verification
87:
59:
50:You can help
40:
1994:Rossi–Forel
1146:in s, and T
1016:teleseismic
411:Forecasting
372:Seismometer
366:Measurement
339:Shadow zone
188:Earthquakes
1817:2008-09-14
1777:2008-09-14
1755:2008-09-14
1723:(4): 354.
1665:2008-09-14
1596:2008-09-14
885:vector sum
782:Definition
560:earthquake
556:seismology
454:Seismology
395:Prediction
334:Hypocenter
268:Supershear
248:Megathrust
243:Intraplate
238:Interplate
223:Aftershock
123:newspapers
1955:(K-class)
1745:128567958
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953:
940:⋅
928:Δ
922:σ
857:Δ
851:σ
820:
596:Gutenberg
324:Epicenter
301:Volcanism
263:Submarine
218:Foreshock
213:Mainshock
54:talk page
2009:Category
1786:cite web
1674:cite web
1559:See also
1170:, using
713:—
554:used in
474:Category
449:Seismite
180:a series
178:Part of
1974:GEOFIAN
1892:Chinese
1725:Bibcode
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1130:where A
600:Richter
273:Tsunami
233:Doublet
137:scholar
1813:. USGS
1743:
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1154:in s.
911:, and
893:period
354:S wave
349:P wave
290:Causes
139:
132:
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118:
110:
52:. The
1989:Omori
1741:S2CID
582:as a
206:Types
144:JSTOR
130:books
1792:link
1680:link
1543:20.6
1447:and
1432:3.27
1401:1.73
1324:3.53
1293:1.54
1203:1.45
937:1.66
598:and
517:The
258:Slow
116:news
1733:doi
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1495:max
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