Search results
Results from the WOW.Com Content Network
A tectonic earthquake begins by an initial rupture at a point on the fault surface, a process known as nucleation. The scale of the nucleation zone is uncertain, with some evidence, such as the rupture dimensions of the smallest earthquakes, suggesting that it is smaller than 100 m while other evidence, such as a slow component revealed by low-frequency spectra of some earthquakes, suggest ...
Evidence of rupture propagation at velocities greater than S wave velocities expected for the surrounding crust have been observed for several large earthquakes associated with strike-slip faults. During strike-slip, the main component of rupture propagation will be horizontal, in the direction of displacement, as a Mode II (in-plane) shear crack.
Lateral propagation will continue until either the rupture reaches a barrier, such as the end of a fault segment, or a region on the fault where there is insufficient stress to allow continued rupture. For larger earthquakes, the depth extent of rupture will be constrained downwards by the brittle-ductile transition zone and upwards by the ...
Unique characteristics of slow slip events include periodicity on timescales of months to years, focus near or down-dip of the locked zone, and along-strike propagation of 5 to 15 km/d. [5] In contrast, a typical earthquake rupture velocity is 70 to 90% of the S wave velocity, or approximately 3.5 km/s.
This is backed up by evidence that the rupture of the 2001 Kunlun earthquake jumped more than 10 km across an extensional stepover. [3] The presence of stepovers during the rupture of strike-slip fault zones has been associated with the initiation of supershear propagation (propagation in excess of the S wave velocity) during earthquake rupture ...
The 1999 Düzce event is the most recent in a sequence of large earthquakes that have affected the North Anatolian Fault, starting towards the eastern end with the 1939 Erzincan earthquake, then propagating towards the west with events in 1942, 1943, 1944, 1951, 1957, 1967 and finally the 1999 İzmit event. At its western end the North ...
Gutenberg–Richter law fitted to the aftershocks of the August 2016 Central Italy earthquake, during the Aug 22 – Sep 1 period.Notice that the linear fit fails at the upper and lower end, due to lack of registered events.
In both the 2004 Indian Ocean earthquake and the 2008 Sichuan earthquake, the aftershock distribution in each case showed that the epicenter (where the rupture initiated) lay to one end of the final area of slip, implying strongly asymmetric rupture propagation.