+ 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

Moments, source dimensions and stress drops of shallow-focus earthquakes in the Tonga-Kermadec Arc



Moments, source dimensions and stress drops of shallow-focus earthquakes in the Tonga-Kermadec Arc



Physics of the Earth and Planetary Interiors: Stresses, slow deformations and fractures in the Earth, Pages 263-278. 1972.



Estimates of moments, source dimensions and stress drops were made for 34 shallow-focus earthquakes in the Tonga arc between 1963 and 1969. Moments were determined from mantle wave spectra and from long period P and S wave spectra. Source dimensions were estimated from the corner frequency of the P and S wave spectra using Brune's (1970) theory. From the moment and the source dimension, the stress drop was approximately determined. Source dimensions and the stress drops increase with moment, and stress drops are typically between a few bars and a few tens of bars for earthquakes with body wave magnitudes of about 512 to 7. In addition, the data suggest regional variations in stress drops. The earthquakes with relatively large stress drops did not occur along the main underthrusting zone of the arc that defines the boundary between the Pacific and Australian plates. These earthquakes, instead, reflect deformation within one plate of lithosphere, and not movement along pre-existing faults that separate two distinct plates. Thus, some of these earthquakes may result from the creation of new faults. High stresses might be expected for such earthquakes because of the high strength of unfaulted rock.

Please choose payment method:






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

Accession: 018268586

Download citation: RISBibTeXText

DOI: 10.1016/0031-9201(72)90010-6


Related references

Moments, Magnitudes, Source Dimensions, and Stresses of Shallow-focus Earthquakes in the Tonga-Kermadec Arc. International Union of Geodesy and Geophysics, 15th General Assembly, Moscow, 1971, Abstracts, 1971

Shallow-Focus Repeating Earthquakes in the Tonga-Kermadec-Vanuatu Subduction Zones. Bulletin of the Seismological Society of America 103.1, 2013

Spatial and temporal clustering of deep and shallow earthquakes in the fiji-tonga-kermadec region. Bulletin of the Seismological Society of America 57(5): 935-938, 1967

Focal mechanisms of deep and shallow earthquakes in the Tonga-Kermadec region and the tectonics of island arcs. Geological Society of America Bulletin 80(8): 1443-1469, 1969

Source dimensions and stress drops of small earthquakes near Parkfield, California. Bulletin of the Seismological Society of America 74(1): 27-40, 1984

Source parameters and stress drops of intermediate and deep focus earthquakes in the New Hebrides arc. Eos, Transactions, American Geophysical Union 60(46): 878, 1979

Earthquake mechanics and deformation in the Tonga-Kermadec subduction zone from fault plane orientations of intermediate- and deep-focus earthquakes. Journal of Geophysical Research: Solid Earth 112(B5), 2007

Seismic moments of the foci of the deep-focus earthquakes of the Fiji-Tonga region. Physics of the Solid Earth 16(4): 238-248, 1980

Source mechanism of shallow earthquakes in the Fiji-Tonga region. Individual Studies by Participants at the International Institute of Seismology and Earthquake Engineering 38(Pages 31-40, 2002

Source Parameters of Intermediate and Deep Focus Earthquakes in the Tonga Arc. International Union of Geodesy and Geophysics, 15th General Assembly, Moscow, 1971, Abstracts, 1971

Measurement of differential rupture durations as constraints on source finiteness of deep-focus Tonga earthquakes. Eos, Transactions, American Geophysical Union 85(47, Suppl, 2004

Stress drops in deep focus earthquakes. Eos, Transactions, American Geophysical Union 50(4): 237, 1969

Rupture characteristics of the 1982 Tonga and 1986 Kermadec earthquakes. Journal of Geophysical Research: Solid Earth 94(B11): 15521-15539, 1989

The focal mechanisms in deep earthquakes in the Fifii-Tonga-Kermadec region. International Union of Geodesy and Geophysics, General Assembly 14(2): 177, 1967

Analysis of the statistical distribution of stress drops and linear dimensions of faults generating earthquakes. Pages 109-116:, 1981