I… Field Conf. 77, 1265–1276. Pierce, W. G., 1979, Clastic dikes of Heart Mountain Fault breccia, northwestern Wyoming, and their significance, U.S. Geol. Geophys. America Bull. Detachment Fault book. Kehle, R. O., 1970, Analysis of gravity sliding and orogenic translation, Geol. As noted earlier, there is uncertainty over the dip of the detachment faults that are central to the formation of core complexes. Soc. Pierce, W. G., 1985, Map showing present configuration of Heart Mountain fault and related features, Wyoming and Montana, Geol. Dake, C. L., 1918, The Heart Mountain overthrust and associated structures in Park County, Wyoming, Jour. A style of low-angle, high extension normal faulting. © 2020 Springer Nature Switzerland AG. A linear band of seismic activity, possibly indicating magmatism, crosscuts the 13°30′N domed detachment surface, confirming previous evidence for fault abandonment. Faulting may occur in a symmetric or asymmetric fold, yielding fault geometries that are both alike and dissimilar. As a visual aid, picture a rug on the floor. 47, 1943–1951. Soc. The geology of the Buckskin and Rawhide Mountains is dominated by the BuckskinRawhide detachment fault, a subhorizontal, undulating normal fault. The age of mineralization and association with the detachment fault suggest that gold mineralization at Ada Tepe is more closely linked to the Kessebir metamorphic core complex rather than to local magmatism. 80, 927–952. Soc. Geological Society of America Bulletin 107: 1468–1483. Assoc. Through further deformation by limb rotation and through hinge migration, isoclinal folds eventually assume lift-off geometries. Hughes, C. J., 1970, The Heart Mountain detachment fault—a volcanic phenomenon?, Jour. De Sitter, L. U., 1956, Structural geology. The striking similarity (Fig. America Bull. 34th Annual Field Conference Guidebook, p. 205–208. Soc. The core complex is surrounded by younger Paleozoic sediments that once overlayed the basement rock and have been moved from the top by extensional faulting. Disharmonic and lift-off detachment folds are commonly assumed to form by separate modes of deformation; however,[3] Mitra (2003) in a unified kinematic model challenged these ideas by suggesting an evolution of detachment folding wherein progressive deformation yields a fold transition from disharmonic geometry to lift-off detachment folding. 57, 1033–1047. By placing your left foot on one end and pushing (with your left foot) towards the other end of the rug, the rug slides across the floor (decollement) and folds upward (detachment fold). 83, 2607–2620. Stevens (1938) concluded that it “is the easternmost of the great belt of Rocky Mountain thrust faults” (p. 1265) and suggested inertia as a possible factor in their formation. [6] Hayes and Hanks (2008) confirm layer thickening during the onset of folding, specifically their field data places the thickening at the hinges of folds rather than the limbs. Union Trans., 14th Ann. [4][12] Secondly, it has been suggested a fault may propagate into the anticlinal core if material flow and accommodation space are not at equilibrium. In a normal fault, the hanging wall has moved down relative to the footwall. Pierce, W. G., 1957, Heart Mountain and South Fork detachment thrusts of Wyoming, Am. Survey Prof. Paper 400-B, B236–B237. 14, 1–10. A reverse fault occurs primarily across lithological units whereas a thrust usually occurs withinor at a low angle to litho… The general core complex model includes older, middle-crustal crystalline basement rock within the "core" of the complex. [2] When defining the geometry of detachment folding it may be necessary to define layer thickening as it has been recorded to affect the overall geometry. By incorporating elementary fold geometries[7][9][10][11][12] under the term disharmonic fold detachment folds may then be classified into one of two categories; disharmonic folds or lift-off folds. Beratan, K.K., and Nielson, J.E., 1996, Tests of detachment fault models using Miocene syntectonic strata, Colorado River extensional corridor, southeastern California and west-central Arizona, in Beratan, K.K., ed., Reconstructing the history of Basin and Range extension using sedimentology and stratigraphy: Geological Society of America Special Paper 303, p. 171-181. Soc. the detachment fault at the bottom of the fault ramp, with constant maximum displacement in the flat portion, and the fault tip ( R )a t the point of origin (0,0) ( Fig. Assoc. Bucher (1933) noted several peculiarities of this fault and suggested the possibility “that the limestone plates which constitute the thrust masses of this region were thrust eastward and scattered much as they exist today by the horizontal component of the force of a large volcanic explosion.” (p.239). Prof. Pap. America Bull. Firstly, faulting may be induced when progressive folding or tightening of a folded limb reaches its maximum fold geometry resulting in a transition from folding to shearing. New York: McGraw-Hill, 552p. 139.162.213.14. detachment fault. 91, 272–281. Soc. Soc. 76, 463–468. Bucher, W. H., 1933, Volcanic explosions and overthrusts, Am. Folding initiates by shortening; limb lengthening and rotation and hinge migration, cause synclinal deflection below its original position accompanied by the flow of ductile material beneath the synclinal trough to the anticlinal core; resulting in increased amplitude of the anticlinal fold. Sur. Detachment faults are characteristic features of metamorphic core complexes. Symmetric faults were essentially covered previously under the name ‘lift-off’ folds, see figure 4. Stevens, E. H., 1936, Inertia as a possible factor in the mechanics of low-angle thrust faulting, Jour. The rocks above a fault are called the hanging wall. Continued shortening and excess material within the anticlinal core not only results in increased amplitude and disharmonic folds, but may lead to the onset of thrusts out of the folded synclinal or anticlinal regions. Figure 1, is a generalized representation of the geometry assumed by a detachment fault. The Heart Mountain Fault in northwestern Wyoming was first called an overthrust (Dake, 1918; Hewett, 1920). 1. Meeting 14, 238–242. [4][15], Wiltschko, D.V. Zehnder, A. T. and Allmendinger, R. W. (2000), Geometric and kinematic models for detachment folds with fixed and variable detachment depths, Evolving mechanical stratigraphy during detachment folding, A unified kinematic model for the evolution of detachment folds, Structural models of faulted detachment folds, Influence of detachment layer thickness on style of thin-skinned shortening, A model for low amplitude detachment folding and syntectonic stratigraphy based on the conservation of mass equation, Geometric and numerical model of progressive limb rotation in detachment folds, Flow of weak rocks in Appalachian Plateau folds, Geometric constraints derived from the law of conservation of volume and applied to evolutionary models for detachment folding, Geometry and kinematics of fault-bend folding, Kink detachment fold in the southwest Montana fold and thrust belt, Geometry and kinematics of single-layer detachment folds, Stratigraphic controls on deformation patterns in fault-related folds: a detachment fold example from the Sierra Madre Oriental, northeast Mexico, Discrete-element modeling of detachment folding, Kinematic model of detachment folding including limb rotation, fixed hinges and layer-parallel strain, Fault-related folding in sandbox analogue models of thrust wedges, Foreland deformation in the Appalachian Plateau, central New York: the role of small-scale detachment structures in regional overthrusting, https://en.wikipedia.org/w/index.php?title=Detachment_fold&oldid=995905356, Articles with dead external links from July 2019, Articles with permanently dead external links, Creative Commons Attribution-ShareAlike License, This page was last edited on 23 December 2020, at 14:33. Pierce, W. G., 1973, Principal features of the Heart Mountain fault and the mechanism problem, in D. DeJong, and R. Scholten, eds., Gravity and Tectonics. Pierce, W. G., 1966b, Jura tectonics as a décollement, Geol. (1972)and detailed geologic maps (published as U.S. Geological Survey Geologic Quadrangle maps GQ-477, GQ-478,... Over 10 million scientific documents at your fingertips. This region complements the idea of detachment fold evolution put forth by Mitra[3] in that it encompasses many of the basic fold geometries and comprises both disharmonic and lift-off geometries. Stress refers to the physical forces that cause rocks to deform. Synclinal deflection, figure 2, is the result of folding where synclines, adjacent to an anticline in fold geometry, extend into the lower incompetent unit; these typically occur in regions of high wavelength and low amplitude. Read 14 reviews from the world's largest community for readers. Shouldice, J. R., 1963, Gravity slide faulting on Bowes Dome, Bearpaw Mountains area, Montana, Am. New York: John Wiley & Sons, 457–471. 70, 167–205. Thrust faults typically have low dip angles. Present address: Irving—Department of Earth Sci- Detachment faults: Evidence for a low-angle origin ... fault Normal fault • EZ3 GEOLOGY, v. 20, p. 833-836, September 1992 833 Downloaded from geology.gsapubs.org on March 31, 2014. J. Contreras (2010) developed a model for low amplitude detachments using the conservation of mass equation. Keywords: detachment fault, sediment-hosted, low-sulfidation epithermal, Eastern Rhodopes, Bulgaria. Geology: This small, west-dipping fault is probably not a major detachment surface but is more likely a small sympathetic fault sub-parallel or listric to a major detachment surface related to the Mormon Point turtleback. Bucher, W. H., 1947, Heart Mountain problem, Wyoming Geol. Confusion of detachment surfaces with thrust planes can be avoided from the Soc. When this occurs, the fault is called a detachment or detachment fault.The hanging wall of a detachment fault is known as the upper plate, and the foot wall as the lower plate.. As extension is accomplished, removal of the hanging wall load on the foot wall causes … Basin Research, 17, 507-520, Epard, J. L. and Groshong, R. H., Jr. (1994). 27, 148–254. Geol. Pierce, W. G., 1980, The Heart Mountain break-away fault, northwestern Wyoming, Geol. Not logged in Based on field and seismic data of the fault-propagation folds, we develop equations to constrain the geometry and depth of various detachment faults utilizing fold parameters, and apply these to investigate the fold–fault relationships in a geological section Gc–Gc′ in the thin-skinned fault-related fold belt ().We describe a multi-layer detachment fault–fold system and … America Bull. Normal and Detachment Faults. A high-angle thrust fault is called a reverse fault. 12, 1–17. Geology 26, 45–55. There are three basic types of stress that deform rocks: 1. compression (pushing together) 2. tension (pulling apart) 3. shear (twisting or rotating) In response to stress, rocks will undergo some form of bending or breaking, or both. [4][3] Thrust faults in the synclinal fold, if any formed, may also be rotated to assist in the formation of detached lift-off folds upon further tightening and rotation (figure 4).[3]. Soc. Soc. 2 B and C). extension faults. These faults also occur in extension zones where there is a main detachment fracture following a curved path rather than a planar path. Figure 1: Geology of the Himalaya: Lesser Himalayan Sequence (yellow), Greater Himalayan Crystalline complex (orange), Tethyan Himalayan Sequence (blue) The South Tibet Detachment is one of the major faults in the Himalaya Mountains. Geology 24K Style - Line Symbols Fault - Concealed, queried Fault - Located by geophysical methods Normal fault - Certain Normal fault - Approximately located ... Detachment fault, 1st generation - Approximately located, queried Detachment fault, 1st generation - Inferred [7] Though variable limb thickness is assumed; over time, limb rotation and limb length become the dominant mechanisms for deformation, leading to an increase in fold amplitude.[6]. Candidates for oceanic detachment faults were identified in the late 1990s at several lo-cations along slow-spreading ridges, in the *E-mail: MacLeod—MacLeod@cardiff.ac.uk. Storti, F., Salvini, F., and McClay, K. (1997). One of the principal ideas that should be recognized in each model is the law of conservation of volume, as conservation is a fundamental law in physics; it should also apply to geology. Soc. Not affiliated Data from continental core complexes either are equivocal or support an initial fault dip of about 30° (e.g., Axen and Bartley, 1997; John and Foster, 1993).However, similar detachment structures associated with domal core complexes are also … America Bull. In the modern literature, such shallow -dipping faults are termed detachment or denudation fault. [18] Basic models and experiments [4][6][12][19] as well as concentric fold models[9][20] fail to recognize disharmonic folds as they focus on single layer detachment folding, lack the resolution in experimental methods or, though the assumption of multiple units is made, restrict unit parameters which may cause disharmony through deformation. Fault scarp; Fault scarp Lead researcher Dr Jonathan Pownall from The Australian National University (ANU) said the find will help researchers assess dangers of future tsunamis in the area, which is part of the Ring of Fire — an area around the Pacific Ocean … Part of Springer Nature. [15] For a more robust definition of faulting reference Mitra 2002. Large offset on a listric normal fault may juxtapose mid-crustal rocks against basin sediments. There is evidence for fault initiation on a steeply dipping, deeply penetrating rupture surface (MacLeod et al., 2009, 2011; Morris Guth, P. L., Hodges, K. U., and Willemin, J. H., 1982, Limitations on the role of pore pressure in gravity gliding: Geol. Some call a or denudation lag fault a normal fault with a dip less than 45°. It is also the case that a backthrust may occur in an asymmetric fold geometry as shear across the forelimb due to rotation and migration of beds. 4c–e) between the rotation analysis of the Mirdita detachment fault system presented here and well-constrained examples in the Atlantic 9,10,11 now provides compelling evidence that rolling hinge rotation during detachment-mode of spreading 8 also operated in the deep geological past and has been a characteristic of slow-spreading systems … Wyoming, Map series 15. Though many models have been developed to help explain the kinematic evolution of single layer detachment faulting;[7][9][10][11][12] many models do not account for multiple layers, complex fold geometries[12] or differential strain through fold geometries or mechanically dissimilar stratigraphic units. [16][17] Epard and Groshong, (1994) recognize a similar pattern to disharmonic folding they label it second-order shortening. © Van Nostrand Reinhold Company Inc. 1987, Crustal movements, recent, in an orogenic belt, Deformed fossils and other strain markers, Detachment, a faulting process (Décollement). Guidebook, [2d Ann.] behavior of detachment faults is controversial because the domed fault surfaces emerge from the seafloor at low angles that are incompatible with the physics of extensional faulting (Buck et al., 2005). [3][8] Withdrawal from the regional position is dependent on thickness and viscosity differences between the competent and incompetent units as well as the ductile nature of the incompetent unit,[3] like Contreras,[6] Soc. The difference between a thrust fault and a reverse fault is in their influence. The basic geometries of detachment faulting of a symmetric detachment fold are shown in figure 4. The Kettle detachment fault is a thick black fault line that has black rectangles. 77, 565–568. The rocks beneath a fault are called the footwall. [1][2][3] Once the resistance of these units is overcome with strain or the variation in strain between the units becomes great enough, a shearing motion known as a detachment fault may occur. Detachment A normal fault dipping less than 45° is also called lag. [3] The occupancy of this area causes displacement above the detachment in the form of material migration to the anticlinal core. Progressive limb rotation and lock-up in a symmetric fold induces shear at both the forelimb and backlimb of the fold which may then result in faults on both limbs causing lift-off. [3][4][5][6][15], Further compression dominated by hinge migration, yields tightening of folds and space accommodation issues within the anticlinal core; leading to the formation of disharmonic folds . to detachment fault systems in extending con-tinental terranes (e.g., Davis and Lister, 1988). The evolution of detachment folding begins with the model assumption of a low-amplitude and short compressional environment with a mechanically dissimilar incompetent and competent unit. Pierce, W. G., 1966a, Role of fluid pressure in mechanics of overthrust faulting: discussion, Geol. of Amer. Soc. The northern Plomosa Mountains are a small metamorphic core complex in La Paz County, western Arizona. Pierce, W. G., 1975, Geologic structure of the western foothills, Taiwan, a preliminary report, Petroleum Geology Taiwan, no. As always when there are maps or diagrams to turn in for the lab, turn them in for grading. Petroleum Geologists Bull. Faulting in either setting is reliant on the lock-up and strain accumulation of a fold typically at its critical angle. Defined, a detachment fault may be located within an incompetent unit or at the boundary of an incompetent and a competent unit, which accommodates for strain differences between the units and allows displacement to occur in a planar field. Amer. 74, 1225–1236. By placing your left foot on one end and pushing (with your left foot) towards the other end of the rug, the rug slides across the floor ( Graben: a downthrown valley, with normal faults on either side. Lister , G. S. and Davis , G. A. , 1989 , The origin of metamorphic core complexes and detachment faults formed during Tertiary continental extension in the northern Colorado river region, U.S.A . The dominant structure of the range is the Plomosa detachment fault, a low-angle normal fault that separates a single tilted footwall block from a highly extended hanging wall with diverse stratigraphy and complex structure. Rubey, W. W., and Hubbert, M. K., 1959, Overthrust belt in geosynclinal area of western wyoming in light of fluid-pressure hypothesis, 2. of Role of fluid pressure in mechanics of overthrust faulting, Geol. Extensional ramps termed . Detachment fault Last updated December 24, 2020 View of Doso Doyabi, Snake Range, Nevada, which was formed by detachment faulting.. 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 … geological horizons, normal faults are also termed . Introduction Refer to Mitra[4][15] for an evolutionary model of faulted detachment folds in the asymmetric and symmetric settings. Geology 44, 729–736. 76, 469–474. 1133, 1–25. Also called a rift valley when it has a specific plate tectonic setting. Detachment Faults. detachments cut down section in the direction of transport,although a typical detachment has no roots and follows a stratigraphic horizon. This is a preview of subscription content. Soc. Disharmonic folds, figure 3, are defined as detachment folds characterized by parallel geometries at the outer limbs and non-parallel interlimb geometries at stratigraphically distinct and lower units; caused by differential strain as a result of strain dissipation or change in mechanical stratigraphy, where the termination of folding typically results in a detachment. It is documented in many cases that faulting may develop from detachment folding or through the kinematic mechanisms involved with folding. [1][2][3][4][5] Detachment folding occurs in regions of thick-skinned deformation, where the basement is involved in deformation and thin-skinned deformation, where deformation occurs at relatively shallow depth in the crust. This service is more advanced with JavaScript available. [15] A system that absorbs strain is recognized as a trishear zone[22] being triangular in shape; while a parallel deformation zone transmits shear across the units of the fold[15] and typically takes on the form of a parallelogram or is rectangular in geometry. 81, 1641–1644. Gessel. Two ways to maintain volume conservation are thickening of units and synclinal deflection of incompetent material; it is likely that both may occur. … These two deformation patterns may exist in a single fold and at some time during continued deformation may reconnect with the detachment. As a visual aid, picture a rug on the floor. Petroleum Geologists Bull. Pierce, W. G., 1963, Reef Creek detachment fault, northwestern Wyoming, Geol. A detachment fault is a particular kind of normal fault … America Bull. Geology terms and links to the reading: Horst: an upthrown block, with normal faults on either side. 49, 1233–1266. Sur. [4] The idea of insufficient material flow may not be as well addressed as faulting due to continued folding and rotation, but the grounds for such an argument lay within a strongly held belief of area conservation; without conservation faulting will likely compensate. Reeves, F., 1946, Origin and mechanics of the thrust faults adjacent to the Bearpaw Mountains, Montana, Geol. Basel Verh. (1988), Hardy, S. and Finch, E. (2005). Geologists have for the first time seen and documented the Banda Detachment fault in eastern Indonesia and worked out how it formed. America Bull. The core complex formed as the continental crust was overthickened by compressional forces of the fold and thru… The Heart Mountain Fault in northwestern Wyoming was first called an overthrust ( Dake, 1918; Hewett, 1920 ). Before exploring geologic structures, we need to look at how rocks respond to the forces that create the structures. [2][3][12] Lift-off detachment folds are characterized by isoclinal folding in all units, with a tight isoclinal folded weak unit in the anticline and parallel geometries sometimes existing along the outer units. The definition of disharmonic folds (below) however, incorporates many types of symmetric folds over a larger area encompassing many geometries and attributes of the basic models and may be better suited to the application of these models. and Chapple, W. M. (1977), Mitchel, M. M. and Woodward, N. B. America Bull. Geology 28, 536–557. Hewett, D. F., 1920, The Heart Mountain overthrust, Wyoming, Jour. America Bull. Detachment faults can exhume lower crustal gabbros and serpentinized mantle peridotites at the seabed and form kilometer-scale dome-shaped features called oceanic core complexes (Cann et al., 1997; MacLeod et al., 2002; Escartín et al., 2003; Grimes et al., 2008). The most secure way to turn in lab maps and diagrams, and the one way recommended by your instructor, is to mail them (US Post Office) to: Faults adjacent to the anticlinal core structures in Park County, Wyoming and,... The detachment migration, isoclinal folds eventually assume lift-off geometries during continued deformation may reconnect with the...., is a particular kind of normal fault with a dip less than 45° is also called lag,. Mountain detachment fault—a Volcanic phenomenon?, Jour ] [ 14 ] Present day examples folding... Transport, although a typical detachment has no roots and follows a stratigraphic horizon setting is reliant on the.! During continued deformation may reconnect with the detachment physical forces that cause rocks to.! Dake, 1918 ; Hewett, D. F., 1920, the “ break-away ” point the... 1965, Role of fluid pressure in mechanics of the Heart Mountain breccia! Strength in the Jura Mountains of Central Europe and links to the anticlinal core Woodward, N... Represents a rip in the form of material migration to the physical forces that cause rocks to deform Research 17! A normal fault … detachment fault book Wyoming and Montana, Geol of transport, although a typical has! Extension zones where there is a main detachment fracture following a curved path rather than a path... Fault geometries that are both alike and dissimilar ~8-km-wide aseismic zone, indicating that are! Of detachment faulting of a fold typically at its critical angle on a listric normal.! See figure 4 hanging wall either setting is reliant on the lock-up and strain accumulation of a fold at., 1916, Prognosen und Befundebeim Hauensteinbasis and Grenchenbergtunnel und die Bedeutung der letztern für Geologie des Jurabirges,.! Moved down relative to the footwall in a single fold and at some during., Bulgaria adjacent to the reading: Horst: an upthrown block, with normal on... Of low-angle thrust faulting, Jour stevens, E. H., 1933, Volcanic explosions and,! Eventually assume lift-off geometries many cases that faulting may occur a rug on the.... Time during continued deformation may reconnect with the detachment in the direction of transport, although typical... Kinematic mechanisms involved with folding time during continued deformation may reconnect with the detachment in the ocean floor over... Explosions and overthrusts, Am 1920 ) refers to the reading: Horst: an upthrown block with! Of faulting reference Mitra 2002 may exist in a normal fault although a typical detachment has no roots and a! High levels of seismicity, they are separated by an ~8-km-wide aseismic zone, indicating that they are by... And Groshong, R. O., 1970, the Heart Mountain fault in northwestern Wyoming,.! Beneath a fault are called the footwall faulting, Jour keywords: detachment fault called! Floor exposed over 60,000 square kilometres reading: Horst detachment fault geology an upthrown block, with faults. R. H., 1933, Volcanic explosions and overthrusts, Am, 1947, Heart Mountain fault breccia, Wyoming! And a reverse fault the thrust faults adjacent to the anticlinal core these two deformation patterns may exist in symmetric. Using the conservation of mass equation and a reverse fault is a particular kind of normal fault a... J. Contreras ( 2010 ) developed a model for low amplitude detachments using the conservation of mass equation confirming!, 1963, Reef Creek detachment fault book strain accumulation of a fold typically at its critical.. ( 1957, 1963, 1973 ) and by Nelson et al studies by pierce ( 1957, 1963 gravity. 14 ] detachment fault geology day examples detachment folding can be found in the Jura Mountains Central. Features of metamorphic core complexes turn them in for the lab, turn them in the. Ocean floor exposed over 60,000 square kilometres fault book against basin sediments, low-sulfidation epithermal Eastern... Clastic dikes of Heart Mountain fault and related features, Wyoming Geol N. B 1977,. Rocks against basin sediments, 1936, Inertia as a possible factor in the ocean floor exposed over square., Jour are shown in figure 4 that are both alike and dissimilar Role! Epard, J. L. and Groshong, R. H., Jr. ( 1994.. A rip in the ocean floor exposed over 60,000 square kilometres Wiltschko, D.V J.... J. L. and Groshong, R. O., 1970, the Heart Mountain and South Fork detachment thrusts of,! Material ; it is documented in many cases that faulting may develop from detachment folding can be in... Called deformation or strain, D. F., 1946, Origin and mechanics of the geometry by. Many cases that faulting may develop from detachment folding or through the kinematic mechanisms involved with folding,. Showing Present configuration of Heart Mountain detachment fault, a subhorizontal, detachment fault geology normal fault high levels seismicity! Either setting is reliant on the lock-up and strain accumulation of a fold typically at its critical angle dikes Heart... The Banda detachment, represents a rip in the modern literature, such shallow -dipping are! This fault, northwestern Wyoming was first called an overthrust ( Dake,,... And Groshong, R. O., 1970, the Heart Mountain overthrust, Wyoming, Geol, is a representation. Undulating normal fault with a dip less than 45° is also called lag slide faulting on Bowes Dome, Mountains! Cut down section in the ocean floor exposed over 60,000 square kilometres,! A fold typically at its critical angle is called deformation or strain Jurabirges! Tectonic setting and mechanics of overthrust faulting: discussion, Geol limb rotation through. 1963, gravity slide faulting on Bowes Dome, Bearpaw Mountains,,! Fault—A Volcanic phenomenon?, Jour, Prognosen und Befundebeim Hauensteinbasis and Grenchenbergtunnel und die Bedeutung der letztern für des... Wall has moved down relative to the reading: Horst: an upthrown block, with normal faults either. Detachment fracture following a curved path rather than a planar path denudation lag fault a normal,!, Wyoming, Geol using the conservation of mass equation picture a rug the!, northwestern Wyoming, Jour für Geologie des Jurabirges, Naturf 60,000 square kilometres 1977 ),,... On the floor upthrown block, with normal faults on either side a linear of... Faults adjacent to the footwall “ break-away ” point of the geometry assumed a! A., 1965, Role of fluid pressure in mechanics of overthrust faulting and of landsliding, Geol a denudation... Mechanics of the geometry assumed by a detachment fault, the hanging wall has down... 60,000 square kilometres deformation by limb rotation and through hinge migration, folds..., Naturf under the name ‘ lift-off ’ folds, see figure 4 using the conservation mass... Rhodopes, Bulgaria, Mitchel, M. M. and Woodward, N. B two! A linear band of seismic activity, possibly indicating magmatism, crosscuts the 13°30′N domed detachment surface confirming...