Estimating Locations and Magnitudes of Earthquakes in Eastern North America from Modified Mercalli Intensities

Bakun, William H.

doi:10.1785/0120020087

Cited by 75 publications

(78 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We also find that the regression underestimates the uncertainties of the location and magnitude of the 1819 Allah Bund earthquake, for which a location has been inferred from mapped surface deformation. Comparing our inferred attenuation relations to those developed for other regions, we find that attenuation for Himalayan events is comparable to intensity attenuation in California (Bakun and Wentworth, 1997), while intensity attenuation for cratonic events is higher than intensity attenuation reported for central/eastern North America (Bakun et al, 2003). Further, we present evidence that intensities of intraplate earthquakes have a nonlinear dependence on magnitude such that attenuation relations based largely on small-to-moderate earthquakes may significantly overestimate the magnitudes of historical earthquakes.…”

supporting

confidence: 61%

“…A comparison of our results with the results of Bakun et al (2003) could be complicated by uncertainties associated with their results. In particular, the intensity values for calibration events used by Bakun et al (2003) have not been systematically reinterpreted and may suffer from the same problems that formerly plagued available intensity values for India.…”

Section: Comparisons With Previous Attenuation Studiesmentioning

confidence: 58%

“…Figure 5 compares intensity attenuation relationships in India with those from eastern North America for a hypothetical M w 6.5 earthquake. For all epicentral distances, the attenuation relationship of Bakun et al (2003) predicts higher intensity observations in eastern North American compared to cratonic India. In contrast, the relationship developed by Atkinson and Wald (2007) agrees with that for cratonic India above intensity V but below intensity V, and these two relationships diverge sharply, with larger intensity values being predicted to greater distances in eastern North America.…”

Section: Comparisons With Previous Attenuation Studiesmentioning

confidence: 89%

“…However, previous authors have inferred systematic differences in both peak ground motion attenuation and weak-motion attenuation between eastern North America and other stable continental regions worldwide (Bakun and McGarr, 2002;Miao and Langston, 2008). Both Bakun et al (2003) and Atkinson and Wald (2007) have developed relationships between intensity and epicentral distance for eastern North America (Table 2). Figure 5 compares intensity attenuation relationships in India with those from eastern North America for a hypothetical M w 6.5 earthquake.…”

Section: Comparisons With Previous Attenuation Studiesmentioning

confidence: 95%

“…In particular, the intensity values for calibration events used by Bakun et al (2003) have not been systematically reinterpreted and may suffer from the same problems that formerly plagued available intensity values for India. To further investigate the difference revealed in Figure 5, we directly compare attenuation from earthquakes of similar magnitude in eastern North America and cratonic India.…”

Section: Comparisons With Previous Attenuation Studiesmentioning

confidence: 99%

See 4 more Smart Citations

Intensity, Magnitude, Location, and Attenuation in India for Felt Earthquakes since 1762

Szeliga¹,

Hough²,

Martin³

et al. 2010

Bulletin of the Seismological Society of America

179

132

View full text Add to dashboard Cite

A comprehensive, consistently interpreted new catalog of felt intensities for India (Martin and Szeliga, 2010, this issue) includes intensities for 570 earthquakes; instrumental magnitudes and locations are available for 100 of these events. We use the intensity values for 29 of the instrumentally recorded events to develop new intensity versus attenuation relations for the Indian subcontinent and the Himalayan region. We then use these relations to determine the locations and magnitudes of 234 historical events, using the method of Bakun and Wentworth (1997). For the remaining 336 events, intensity distributions are too sparse to determine magnitude or location. We evaluate magnitude and location accuracy of newly located events by comparing the instrumental-with the intensity-derived location for 29 calibration events, for which more than 15 intensity observations are available. With few exceptions, most intensity-derived locations lie within a fault length of the instrumentally determined location. For events in which the azimuthal distribution of intensities is limited, we conclude that the formal error bounds from the regression of Bakun and Wentworth (1997) do not reflect the true uncertainties. We also find that the regression underestimates the uncertainties of the location and magnitude of the 1819 Allah Bund earthquake, for which a location has been inferred from mapped surface deformation. Comparing our inferred attenuation relations to those developed for other regions, we find that attenuation for Himalayan events is comparable to intensity attenuation in California (Bakun and Wentworth, 1997), while intensity attenuation for cratonic events is higher than intensity attenuation reported for central/eastern North America (Bakun et al., 2003). Further, we present evidence that intensities of intraplate earthquakes have a nonlinear dependence on magnitude such that attenuation relations based largely on small-to-moderate earthquakes may significantly overestimate the magnitudes of historical earthquakes.

show abstract

supporting

confidence: 61%

Section: Comparisons With Previous Attenuation Studiesmentioning

confidence: 58%