Search results
Results From The WOW.Com Content Network
Energy release associated with rapid movement on active faults is the cause of most earthquakes. Faults may also displace slowly, by aseismic creep. [2] A fault plane is the plane that represents the fracture surface of a fault. A fault trace or fault line is a place where the fault can be seen
An active fault is a fault that is likely to become the source of another earthquake sometime in the future. Geologists commonly consider faults to be active if there has been movement observed or evidence of seismic activity during the last 10,000 years. [1] Active faulting is considered to be a geologic hazard – one related to earthquakes as
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 ...
In the case of a fault-related event, it refers to the orientation of the fault plane that slipped, and the slip vector and is also known as a fault-plane solution. Focal mechanisms are derived from a solution of the moment tensor for the earthquake, which itself is estimated by an analysis of observed seismic waveforms. The focal mechanism can ...
In its most general sense, the word earthquake is used to describe any seismic event that generates seismic waves. Earthquakes can occur naturally or be induced by human activities, such as mining, fracking, and nuclear tests. The initial point of rupture is called the hypocenter or focus, while the ground level directly above it is the epicenter.
San Andreas Fault System (Banning fault, Mission Creek fault, South Pass fault, San Jacinto fault, Elsinore fault) 1300: California, United States: Dextral strike-slip: Active: 1906 San Francisco (M7.7 to 8.25), 1989 Loma Prieta (M6.9) San Ramón Fault: Chile: Thrust fault: Sawtooth Fault: Idaho, United States: Normal fault: Seattle Fault ...
For a fault being stressed to the point of an earthquake, these bonds begin to stretch and break. They do not have time to heal again. Once the critical distance has been achieved, there is a significant strength loss, and the fault begins to slide. Earthquakes only exist because there is a very large loss in frictional strength.
The thrust faults responsible for megathrust earthquakes often lie at the bottom of oceanic trenches; in such cases, the earthquakes can abruptly displace the sea floor over a large area. As a result, megathrust earthquakes often generate tsunamis that are considerably more destructive than the earthquakes themselves.