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The superposition of individual strain components can be expressed at the tectonic scale involving oblique convergent margins and transpression / transtension tectonic regimes.<ref name=Jones&Tanner />

The superposition of individual strain components can be expressed at the tectonic scale involving oblique convergent margins and transpression / transtension tectonic regimes.<ref name=Jones&Tanner />

===Oblique convergent margins===

===Oblique convergent margins===

[[File:Obconv2.jpeg|500px|thumbnail|right|Block diagram illustrating strain partitioning at an oblique [[Convergent boundary|convergent margin]]. The obliquity of plate convergence (blue arrows) induces stress components that are normal to the margin (yellow arrow) and parallel to the margin (green arrow). Elevated magnitudes of the arc parallel component induces horizontal translation (red arrows) between the wedge and the backstop. Adapted and modified from Platt, 1993.<ref name=Platt93 />]]

[[File:Obconv2.jpeg|500px|thumbnail|right|Block diagram illustrating strain partitioning at an oblique [[Convergent boundary|convergent margin]]. The obliquity of plate convergence (blue arrows) induces stress components that are normal to the margin (yellow arrow) and parallel to the margin (green arrow). Elevated magnitudes of the arc parallel component induces horizontal translation (red arrows) between the wedge and the backstop. Adapted and modified from Platt, 1993.<ref name=Platt93 /> please click on the figure for a better image]]

Convergent margins where the angle of subduction is oblique will often result in the partitioning of strain into an arc parallel component (accommodated by strike slip faults or shear zones) and an arc normal component (accommodated through [[thrust fault]]s).<ref name=Platt93>Platt, J.P. (1993). "Mechanics of Oblique Convergence". Journal of Geophysical Research 98 (B9): 16,239–16,256.</ref><ref name=McCaffery92>McCaffrey, Robert (1992). "Oblique Plate Convergence, Slip Vectors, and Forearc Deformation". Journal of Geophysical Research 97 (B6): 8905–8915.</ref> This occurs as a response to shear stress exerted at the base of the overriding plate that is not perpendicular to the plate margin.<ref name=Platt93 /><ref name=Platt93 /><ref name=McCaffery92 /><ref name=Styron>Syron, Richard; Taylor, Michaeal; Murphy, Michael (2011). "Oblique convergence, arc-parallel extension, and the role of strike-slip faulting in the High Himalaya". Geosphere 7 (2): 582–596. doi:10.1130/GES00606.1.</ref>

Convergent margins where the angle of subduction is oblique will often result in the partitioning of strain into an arc parallel component (accommodated by strike slip faults or shear zones) and an arc normal component (accommodated through [[thrust fault]]s).<ref name=Platt93>Platt, J.P. (1993). "Mechanics of Oblique Convergence". Journal of Geophysical Research 98 (B9): 16,239–16,256.</ref><ref name=McCaffery92>McCaffrey, Robert (1992). "Oblique Plate Convergence, Slip Vectors, and Forearc Deformation". Journal of Geophysical Research 97 (B6): 8905–8915.</ref> This occurs as a response to shear stress exerted at the base of the overriding plate that is not perpendicular to the plate margin.<ref name=Platt93 /><ref name=Platt93 /><ref name=McCaffery92 /><ref name=Styron>Syron, Richard; Taylor, Michaeal; Murphy, Michael (2011). "Oblique convergence, arc-parallel extension, and the role of strike-slip faulting in the High Himalaya". Geosphere 7 (2): 582–596. doi:10.1130/GES00606.1.</ref>

The [[Coast Mountains]] of British Columbia are interpreted as a transpressive orogen which formed during the [[Cretaceous]].<ref name=CPCTect>Chardon, Dominique; Andronicos, Christopher; Hollister, Lincoln (1999). "Large-scale transpressive shear zone patterns and displacements within magmatic arcs: The Coast Plutonic Complex, British Columbia". Tectonics 18 (2): 278–292.</ref> Oblique subduction induced the development of several shear zones which strike parallel to the orogen.<ref name=CPCTect /> The presence of these shear zones suggest that strain is partitioned within the Coast Orogen which resulted in horizontal translation of terranes for several hundred kilometers parallel to the orogen.<ref name=CPCTect />  

The [[Coast Mountains]] of British Columbia are interpreted as a transpressive orogen which formed during the [[Cretaceous]].<ref name=CPCTect>Chardon, Dominique; Andronicos, Christopher; Hollister, Lincoln (1999). "Large-scale transpressive shear zone patterns and displacements within magmatic arcs: The Coast Plutonic Complex, British Columbia". Tectonics 18 (2): 278–292.</ref> Oblique subduction induced the development of several shear zones which strike parallel to the orogen.<ref name=CPCTect /> The presence of these shear zones suggest that strain is partitioned within the Coast Orogen which resulted in horizontal translation of terranes for several hundred kilometers parallel to the orogen.<ref name=CPCTect />  

[[File:TranpTrans2.jpeg|600px|thumbnail|center|Block diagram illustrating the difference between homogeneous and partitioned strain within transpressive and transtensive tectonic regimes. The partitioning of strain occurs through the development of a strike slip or shear zone (shown with red arrows) across the actively deforming region (brown). Adaptation and modification from (Teyssier et al, 1995;<ref name=TyesTik>Teyssier, Christian; Tikoff, Basil; Markley, Michelle (1995). "Oblique plate motion and continental tectonics". Geology 23 (5). doi:10.1130/0091-7613(1995)023<0447:OPMACT>2.3.CO;2.</ref> Fossen, 2012;<ref name=Fossen /> Jones and Tanner, 1995;<ref name=Jones&Tanner /> Sanderson and Marchini, 1984<ref name=Transpression />)]]

[[File:TranpTrans2.jpeg|600px|thumbnail|center|Block diagram illustrating the difference between homogeneous and partitioned strain within transpressive and transtensive tectonic regimes. The partitioning of strain occurs through the development of a strike slip or shear zone (shown with red arrows) across the actively deforming region (brown). Adaptation and modification from (Teyssier et al, 1995;<ref name=TyesTik>Teyssier, Christian; Tikoff, Basil; Markley, Michelle (1995). "Oblique plate motion and continental tectonics". Geology 23 (5). doi:10.1130/0091-7613(1995)023<0447:OPMACT>2.3.CO;2.</ref> Fossen, 2012;<ref name=Fossen /> Jones and Tanner, 1995;<ref name=Jones&Tanner /> Sanderson and Marchini, 1984<ref name=Transpression />)please click on the figure for a better image]]

Strain factorization is a mathematical approach to quantify and characterize the variation of strain components in terms of the intensity and distribution that produces the finite strain throughout a deformed region.<ref name=Transpression>Sanderson, David; Marchini, W.R.D. (1984). "Transpression". Journal of Structural Geology 6 (5): 449–458.</ref><ref name=RamsayHuber1 /><ref name=RamsayHuber2 /><ref name=Evans&Dunne>Evans, Mark; Dunne, William (1991). "Strain factorization and partitioning in the North Mountain thrust sheet, central Appalachians, U.S.A.". Journal of Structural Geology 13 (1): 21–35.</ref> This effort is achieved through matrix multiplication.<ref name=RamsayHuber1>Ramsay, John; Huber, Martin (1983). The Techniques of Modern Structural Geology Volume 1: Strain Analysis. London: Academic Press. ISBN 0-12-576901-6.</ref><ref name=RamsayHuber2>Ramsay, John; Huber, Martin (1987). The Techniques of Modern Structural Geology Volume 2: Folds and Fractures. London: Academic Press. ISBN 0-12-576902-4.</ref> Refer to the figure below to conceptually visualize what is obtained through strain factorization.

Strain factorization is a mathematical approach to quantify and characterize the variation of strain components in terms of the intensity and distribution that produces the finite strain throughout a deformed region.<ref name=Transpression>Sanderson, David; Marchini, W.R.D. (1984). "Transpression". Journal of Structural Geology 6 (5): 449–458.</ref><ref name=RamsayHuber1 /><ref name=RamsayHuber2 /><ref name=Evans&Dunne>Evans, Mark; Dunne, William (1991). "Strain factorization and partitioning in the North Mountain thrust sheet, central Appalachians, U.S.A.". Journal of Structural Geology 13 (1): 21–35.</ref> This effort is achieved through matrix multiplication.<ref name=RamsayHuber1>Ramsay, John; Huber, Martin (1983). The Techniques of Modern Structural Geology Volume 1: Strain Analysis. London: Academic Press. ISBN 0-12-576901-6.</ref><ref name=RamsayHuber2>Ramsay, John; Huber, Martin (1987). The Techniques of Modern Structural Geology Volume 2: Folds and Fractures. London: Academic Press. ISBN 0-12-576902-4.</ref> Refer to the figure below to conceptually visualize what is obtained through strain factorization.

[[File:SpFactor3.jpeg|600px|thumbnail|center|Conceptual illustration of strain factorization. This highlights how the order of superposition of pure and simple shear components produce differing geometries, as matrix multiplication is non-communicative. Adaptation and modifications from Ramsay and Huber, 1983;<ref name=RamsayHuber1 /> Ramsay and Huber, 1987<ref name=RamsayHuber2 />]]

[[File:SpFactor3.jpeg|600px|thumbnail|center|Conceptual illustration of strain factorization. This highlights how the order of superposition of pure and simple shear components produce differing geometries, as matrix multiplication is non-communicative. Adaptation and modifications from Ramsay and Huber, 1983;<ref name=RamsayHuber1 /> Ramsay and Huber, 1987<ref name=RamsayHuber2 />please click on the figure for a better image]]

==Influence of rock material rheology==

==Influence of rock material rheology==

At the grain and crystal scale, strain partitioning may occur between minerals (or clasts and matrix) governed by their [[rheological]] contrasts.<ref name=Carreras /><ref name=AGI>Neuendorf, Kaus; Mehl, James; Jackson, Julia (2005). Glossary of Geology (5 ed.). Alexandria, VA, United States: American Geological Institute.</ref><ref name=GoodwinTikoff>Goodwin, Laurel; Tikoff, Basil (2002). "Competency contrast, kinematics, and the development of foliations and lineations in the crust". Journal of Structural Geology 24 (6-7): 1065–1085.</ref><ref name=Japan>Michibayashi, Katsuyoshi; Murakami, Masami (2007). "Development of a shear band cleavage as a result of strain partitioning". Journal of Structural Geology 29 (6): 1070–1082. doi:10.1016/j.jsg.2007.02.003.</ref> Constituent minerals of differing rheological properties in a rock will accumulate strain differently, thus inducing mechanically preferable structures and fabrics.<ref name=GoodwinTikoff /><ref name=Japan />

At the grain and crystal scale, strain partitioning may occur between minerals (or clasts and matrix) governed by their [[rheological]] contrasts.<ref name=Carreras /><ref name=AGI>Neuendorf, Kaus; Mehl, James; Jackson, Julia (2005). Glossary of Geology (5 ed.). Alexandria, VA, United States: American Geological Institute.</ref><ref name=GoodwinTikoff>Goodwin, Laurel; Tikoff, Basil (2002). "Competency contrast, kinematics, and the development of foliations and lineations in the crust". Journal of Structural Geology 24 (6-7): 1065–1085.</ref><ref name=Japan>Michibayashi, Katsuyoshi; Murakami, Masami (2007). "Development of a shear band cleavage as a result of strain partitioning". Journal of Structural Geology 29 (6): 1070–1082. doi:10.1016/j.jsg.2007.02.003.</ref> Constituent minerals of differing rheological properties in a rock will accumulate strain differently, thus inducing mechanically preferable structures and fabrics.<ref name=GoodwinTikoff /><ref name=Japan />

==Individual deformation mechanisms==

==Individual deformation mechanisms==

[[File:MechPart2.jpeg|300px|thumbnail|right|Simplistic illustration of different deformation mechanisms which produce the finite strain. Citation for different types of deformation mechanisms acquired from (Passchier and Trouw, 2005)<ref name=Micro-tectonics>Passchier, Cees; Trouw, Rudolph (2005). Micro-tectonics (5th ed.). New York: Springer. ISBN 3-540-64003-7.</ref>]]Strain partitioning is also known as a procedure for decomposing the overall strain into individual [[deformation mechanisms]] which allowed for strain to be accommodated.<ref name=RamsayHuber1 /> This approach is performed from geometrical analysis of rocks on the grain - crystal scale.<ref name=RamsayHuber1 /> Strain partitioning of deformation mechanisms incorporates those mechanisms which occur both simultaneously and/or subsequently as tectonic conditions evolve, as deformation mechanisms are a function of strain rate and pressure-temperature conditions.<ref name=RamsayHuber1 /><ref name=Evans&Dunne /> Performing such a procedure is important for structural and tectonic analysis as it provides parameters and constraints for constructing deformation models.<ref name=Evans&Dunne /><ref name=Mitra76>Mitra, Shankar (1976). "A Quantitative Study of Deformation Mechanisms and Finite Strain in Quartzites". Contributions to Mineralogy and Petrology 59: 203–226.</ref>   

[[File:MechPart2.jpeg|300px|thumbnail|right|Simplistic illustration of different deformation mechanisms which produce the finite strain. Citation for different types of deformation mechanisms acquired from (Passchier and Trouw, 2005)<ref name=Micro-tectonics>Passchier, Cees; Trouw, Rudolph (2005). Micro-tectonics (5th ed.). New York: Springer. ISBN 3-540-64003-7.</ref>please click on the figure for a better image]]Strain partitioning is also known as a procedure for decomposing the overall strain into individual [[deformation mechanisms]] which allowed for strain to be accommodated.<ref name=RamsayHuber1 /> This approach is performed from geometrical analysis of rocks on the grain - crystal scale.<ref name=RamsayHuber1 /> Strain partitioning of deformation mechanisms incorporates those mechanisms which occur both simultaneously and/or subsequently as tectonic conditions evolve, as deformation mechanisms are a function of strain rate and pressure-temperature conditions.<ref name=RamsayHuber1 /><ref name=Evans&Dunne /> Performing such a procedure is important for structural and tectonic analysis as it provides parameters and constraints for constructing deformation models.<ref name=Evans&Dunne /><ref name=Mitra76>Mitra, Shankar (1976). "A Quantitative Study of Deformation Mechanisms and Finite Strain in Quartzites". Contributions to Mineralogy and Petrology 59: 203–226.</ref>