+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Moment magnitude-local magnitude calibration for earthquakes in Western Canada



Moment magnitude-local magnitude calibration for earthquakes in Western Canada



Bulletin of the Seismological Society of America 95(5): 1994-2000



Local magnitude (M (sub L) ) is the primary magnitude scale calculated for western Canada by the Geological Survey of Canada (GSC). Moment magnitude (M (sub w) ), derived from moment tensor analysis, provides a more robust estimate of the magnitude of earthquakes but is more demanding to calculate. Moment tensor analysis of regional seismic data for earthquakes with magnitudes larger than 3.5 in western Canada is now possible owing to the installation of more than 40 three-component broadband stations in western Canada, the Pacific Northwest of the United States, and southeast Alaska. More than 100 regional moment tensor solutions have been calculated in the Canadian Cordillera and Vancouver Island/Puget Sound region for 1996-2004 at the GSC. These solutions, along with 45 prior solutions, allow the calibration of M (sub w) -M (sub L) throughout much of western Canada. Continental crust events in the Canadian Cordillera and Vancouver Island/Puget Sound region are found to have M (sub w) = M (sub L) for earthquakes with M (sub L) > or =3.6. In contrast, earthquakes located within the subducting slab in the Vancouver Island/Puget Sound region, where there are complex source-receiver travel paths, have M (sub w) systematically larger than M (sub L) by nearly 0.6 magnitude units. The calibrations of M (sub w) with M (sub L) are an important result that will allow the western Canadian earthquake database to be used more effectively for tectonic studies and seismic hazard analysis.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 019472246

Download citation: RISBibTeXText

DOI: 10.1785/0120050028


Related references

Moment magnitude-local magnitude calibration for earthquakes off Canada's west coast. Bulletin of the Seismological Society of America 93(5): 2296-2300, 2003

Comparison of magnitude estimates for New Zealand earthquakes; moment magnitude, local magnitude, and teleseismic body-wave magnitude. Bulletin of the Seismological Society of America 99.3, 2009

Empirical relationship between moment magnitude and Nuttli magnitude for small-magnitude earthquakes in southeastern Canada. Seismological Research Letters 76(6): 752-755, 2005

Local magnitude, duration magnitude and seismic moment of Dahshour 1992 earthquakes. Annali di Geofisica 43(1): 95-103, 2000

Moment Magnitude MW and Local Magnitude ML Relationship for Earthquakes in Northeast India. Pure and Applied Geophysics 169(11): 1977-1988, 2012

Empirical Calibration of Local Magnitude Data Sets Versus Moment Magnitude in Italy. Bulletin of the Seismological Society of America 103(4): 2227-2246, 2013

Scaling relations of local magnitude versus moment magnitude for sequences of similar earthquakes in Switzerland. Bulletin of the Seismological Society of America 101.2, 2011

Moment magnitude local magnitude relationship for the earthquakes of the Shillong-Mikir plateau, Northeastern India Region: a new perspective. Geomatics Natural Hazards and Risk 3(4): 365-375, 2012

A Local Magnitude Relation for Earthquakes in the Western Canada Sedimentary Basin. Bulletin of the Seismological Society of America 107(3): 1421-1431, 2017

Automatic computation of moment magnitudes for small earthquakes and the scaling of local to moment magnitude. Geophysical Journal International 183.1, 2010

Body-Wave Magnitude mb Is a Good Proxy of Moment Magnitude Mw for Small Earthquakes (mb<4.5-5.0). Seismological Research Letters 84(6): 932-937, 2013

A revised magnitude-recurrence relation for shallow crustal earthquakes in southwestern British Columbia; considering the relationships between moment magnitude and regional magnitudes. Bulletin of the Seismological Society of America 95(1): 334-340, 2005

A local earthquake coda magnitude and its relation to duration, moment M<O) , and local Richter magnitude M<L). Eos, Transactions, American Geophysical Union: 2, Pages 1193. 1977., 1977

Moment magnitude determination for local and regional earthquakes based on source spectra. Bulletin of the Seismological Society of America 93(1): 203-214, 2003

Calibration of local magnitude in case of crustal earthquakes for Romania. Geophysical Research Abstracts 11, 2009