Detachment fault
Encyclopedia
Detachment faulting is associated with large-scale extensional tectonics
. Detachment faults often have very large displacements (tens of km) and juxtapose unmetamorphosed hanging walls against medium to high-grade metamorphic
footwalls that are called metamorphic core complex
es. They are thought to have formed as either initially low-angle structures or by the rotation of initially high-angle normal faults modified also by the isostatic effects of tectonic denudation.
Examples of detachment faulting include:
Detachment faults have been found on the sea floor close to divergent plate boundaries characterised by a limited supply of upwelling magma. These detachment faults are associated with the development of oceanic core complex structures.
Extensional tectonics
Extensional tectonics is concerned with the structures formed, and the tectonic processes associated with, the stretching of the crust or lithosphere.-Deformation styles:...
. Detachment faults often have very large displacements (tens of km) and juxtapose unmetamorphosed hanging walls against medium to high-grade metamorphic
Metamorphic rock
Metamorphic rock is the transformation of an existing rock type, the protolith, in a process called metamorphism, which means "change in form". The protolith is subjected to heat and pressure causing profound physical and/or chemical change...
footwalls that are called metamorphic core complex
Metamorphic core complex
Metamorphic core complexes are exposures of deep crust exhumed in association with largely amagmatic extension. They form, and are exhumed, through relatively fast transport of middle and lower continental crust to the Earth's surface...
es. They are thought to have formed as either initially low-angle structures or by the rotation of initially high-angle normal faults modified also by the isostatic effects of tectonic denudation.
Examples of detachment faulting include:
- The Snake RangeSnake RangeThe Snake Range is a line of high mountains in eastern White Pine County, in east-central Nevada in the western United States. Typical of other ranges in the Basin and Range Province, it runs in a north-south direction, in this case for approximately...
detachment system of the Basin and RangeBasin and RangeThe Basin and Range Province is a vast physiographic region defined by a unique topographic expression. Basin and Range topography is characterized by abrupt changes in elevation, alternating between narrow faulted mountain chains and flat arid valleys or basins...
Province of western North America which was active during the MioceneMioceneThe Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene... - The Nordfjord-Sogn Detachment of western Norway active during the DevonianDevonianThe Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya , to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya...
Period - The Whipple detachmentWhipple MountainsThe Whipple Mountains, 'Avii Kur'utat in the Mojave language, are located in eastern San Bernardino County, California. They are directly west of the Colorado River, Parker Dam, and Lake Havasu; south of Needles, California; north of Parker, Arizona and Vidal, California; and northeast of Vidal...
in southeastern California
Detachment faults have been found on the sea floor close to divergent plate boundaries characterised by a limited supply of upwelling magma. These detachment faults are associated with the development of oceanic core complex structures.