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This list covers all faults and fault-systems that are either geologically important [clarification needed] or connected to prominent seismic activity. [clarification needed] It is not intended to list every notable fault, but only major fault zones.
Globally most fault zones are located on divergent plate boundaries on oceanic crust. This means that they are located around mid-ocean ridges and trend perpendicular to them. The term fracture zone is used almost exclusively for features on oceanic crust; similar structures on continental crust are instead termed transform or strike slip faults.
The Queen Charlotte Fault is an active transform fault that marks the boundary of the North American plate and the Pacific plate. [ 1 ] [ 2 ] It is Canada 's right-lateral strike-slip equivalent to the San Andreas Fault to the south in California . [ 3 ]
In Cascadia, these events are marked by about two weeks of 1 to 10 Hz seismic trembling and non-earthquake ("aseismic") slip on the plate boundary equivalent to a magnitude 7 earthquake. (Tremor is a weak seismological signal only detectable by very sensitive seismometers.)
The Almanor Fault Zone contains both strike-slip faults, where the earth moves from side to side; and “normal” faults, “where there’s extension in the crust, so things are being pulled ...
A fault trace or fault line is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geologic maps to represent a fault. [3] [4] A fault zone is a cluster of parallel faults. [5] [6] However, the term is also used for the zone of crushed rock along a single fault. [7]
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 ...
As illustrated, an earthquake zone may start as a single crack, growing to form many individual cracks and collections of cracks along a fault. The key to fault growth is the concept of a "following force", as conveniently provided for interplate earthquakes, by the motion of tectonic plates. Under a following force, the seismic displacements ...