Transpression and transtension zones

Abstract Transpression and transtension are strike-slip deformations that deviate from simple shear because of a component of, respectively, shortening or extension orthogonal to the deformation zone. These three-dimensional non-coaxial strains develop principally in response to obliquely convergent or divergent relative motions across plate boundary and other crustal deformation zones at various scales. The basic constant-volume strain model with a vertical stretch can be modified to allow for volume change, lateral stretch, an oblique simple shear component, heterogeneous strain and steady-state transpression and transtension. The more sophisticated triclinic models may be more realistic but their mathematical complexity may limit their general application when interpreting geological examples. Most transpression zones generate flattening (k < 1) and transtension zones constrictional (k > 1) finite strains, although exceptions can occur in certain situations. Relative plate motion vectors, instantaneous strain (or stress) axes and finite strain axes are all oblique to one another in transpression and transtension zones. Kinematic partitioning of non-coaxial strike-slip and coaxial strains appears to be a characteristic feature of many such zones, especially where the far-field (plate) displacement direction is markedly oblique (<20°) to the plate or deformation zone boundary. Complex foliation, lineation and other structural patterns are also expected in such settings, resulting from switching or progressive rotation of finite strain axes. The variation in style and kinematic linkage of transpressional and transtensional structures at different crustal depths is poorly understood at present but may be of central importance to understanding the relationship between deformation in the lithospheric mantle and crust. Existing analyses of obliquely convergent and divergent zones highlight the importance of kinematic boundary conditions and imply that stress may be of secondary importance in controlling the dynamics of deformation in the crust and lithosphere.

[1]  B. Tikoff,et al.  The deformation matrix for simultaneous simple shearing, pure shearing and volume change, and its application to transpression-transtension tectonics , 1993 .

[2]  T. Fitch.  Plate convergence, transcurrent faults, and internal deformation adjacent to Southeast Asia and the western Pacific , 1972 .

[3]  C. Teyssier,et al.  Strain modeling of displacement-field partitioning in transpressional orogens , 1994 .

[4]  A. Bally,et al.  Transpression, orogenic float, and lithospheric balance , 1990 .

[5]  J. Ramsay,et al.  The techniques of modern structural geology. Volume 2, Foldsand fractures , 1987 .

[6]  B. Dutton.  Finite strains in transpression zones with no boundary slip , 1997 .

[7]  J. Dewey,et al.  Shortening of continental lithosphere: the neotectonics of Eastern Anatolia — a young collision zone , 1986, Geological Society, London, Special Publications.

[8]  H. A. Lallemant,et al.  Role of extensional tectonics in exhumation of eclogites and blueschists in an oblique subduction setting: Northeastern Venezuela , 1990 .

[9]  M. Brown,et al.  Granite magma generation, ascent and emplacement within a transpressional orogen , 1992, Journal of the Geological Society.

[10]  A. Ribeiro,et al.  Constriction in a transpressive regime: an example in the Iberian branch of the Ibero-Armorican arc , 1994 .

[11]  N. Kusznir,et al.  Modelling of near-field subsurface displacements for generalized faults and fault arrays , 1993 .

[12]  R. Mccaffrey.  Oblique plate convergence, slip vectors, and forearc deformation , 1992 .

[13]  W. Jamison.  Kinematics of compressional fold development in convergent wrench terranes , 1991 .

[14]  J. Dewey,et al.  Active tectonics of the Andes , 1992 .

[15]  A. Gates,et al.  Three-dimensional shuffling of horses in a strike-slip duplex: An example from the Lambertville sill, New Jersey , 1996 .

[16]  W. B. Harland.  Tectonic transpression in Caledonian Spitsbergen , 1971, Geological Magazine.

[17]  Graham Yielding,et al.  The geometry of normal faults , 1990, Journal of the Geological Society.

[18]  S. Cox,et al.  Coupled grain-scale dilatancy and mass transfer during deformation at high fluid pressures: examples from Mount Lyell, Tasmania , 1989 .

[19]  D. Nieuwland,et al.  Modern Developments in Structural Interpretation, Validation And Modelling , 1995 .

[20]  T. P. Harding.  Petroleum Traps Associated with Wrench Faults , 1974 .

[21]  A. Gibbs.  Strike-slip Basins and Inversion: a possible model for the Southern North Sea Gas Areas , 1986, Geological Society, London, Special Publications.

[22]  R. Holdsworth.  Structural evolution of the Gander-Avalon terrane boundary: a reactivated transpression zone in the NE Newfoundland Appalachians , 1994, Journal of the Geological Society.

[23]  E. Lundin,et al.  Cenozoic compressional structures on the NE Atlantic margin; nature, origin and potential significance for hydrocarbon exploration , 1996, Petroleum Geoscience.

[24]  R. Holdsworth,et al.  Oblique simple shear in transpression zones , 1998, Geological Society, London, Special Publications.

[25]  Basil Tikoff,et al.  Oblique plate motion and continental tectonics , 1995 .

[26]  Nick Kusznir,et al.  A flexural-cantilever simple-shear/pure-shear model of continental lithosphere extension: applications to the Jeanne d’Arc Basin, Grand Banks and Viking Graben, North Sea , 1991, Geological Society, London, Special Publications.

[27]  J. Platt.  MECHANICS OF OBLIQUE CONVERGENCE , 1993 .

[28]  Basil Tikoff,et al.  Stretching lineations in transpressional shear zones: an example from the Sierra Nevada Batholith , 1997 .

[29]  B. Tikoff,et al.  Simultaneous pure and simple shear: the unifying deformation matrix , 1993 .

[30]  Nick Kusznir,et al.  3‐D subsurface displacement and strain fields for faults and fault arrays in a layered elastic half‐space , 1992 .

[31]  Angus M. McCoss.  Simple constructions for deformation in transpression/transtension zones , 1986 .

[32]  E. R. Engdahl,et al.  Earthquake source parameters and stress distribution in the Adak Island region of the central Aleuti , 1989 .

[33]  R. Holdsworth,et al.  The recognition of reactivation during continental deformation , 1997, Journal of the Geological Society.

[34]  Richard R. Jones,et al.  Strain partitioning in transpression zones , 1995 .

[35]  E. M. Anderson.  The dynamics of faulting , 1905, Transactions of the Edinburgh Geological Society.

[36]  W. Schwerdtner.  The solid-body tilt of deformed paleohorizontal planes: application to an Archean transpression zone, southern Canadian Shield , 1989 .

[37]  R. Holdsworth,et al.  Lateral extrusion in transpression zones: the importance of boundary conditions , 1997 .

[38]  D. S. Wood.  A Discussion on the measurement and interpretation of changes of strain in the Earth - Patterns and magnitudes of natural strain in rocks , 1973, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[39]  R. Holdsworth.  Short Paper: The Start-Perranporth line: a Devonian terrane boundary in the Variscan orogen of SW England? , 1989, Journal of the Geological Society.

[40]  P. Williams,et al.  Deformation path partitioning within a transpressive shear zone, Marble Cove, Newfoundland , 1996 .

[41]  A. Ries,et al.  The relation between regionally consistent stretching lineations and plate motions , 1984 .

[42]  H. Ramberg.  Particle paths, displacement and progressive strain applicable to rocks , 1975 .

[43]  R. Mccaffrey.  Slip vectors and stretching of the Sumatran fore arc , 1991 .

[44]  R. E. Wilcox,et al.  Basic Wrench Tectonics , 1973 .

[45]  P. Molnar.  Chapter 18 Brace-Goetze Strength Profiles, The Partitioning of Strike-slip and Thrust Faulting at Zones of Oblique Convergence, and the Stress-Heat Flow Paradox of the San Andreas Fault , 1992 .

[46]  H. Fossen.  Indication of transpressional tectonics in the Gullfaks oil-field, northern North Sea , 1989 .

[47]  A. Michael.  Energy constraints on kinematic models of oblique faulting: Loma Prieta versus Parkfield-Coalinga , 1990 .

[48]  D. Schultz-Ela,et al.  Transpression in an Archean greenstone belt, northern Minnesota , 1988 .

[49]  M. Ellis,et al.  Orogen-parallel extension and oblique tectonics; the relation between stretching lineations and relative plate motions , 1987 .

[50]  Basil Tikoff,et al.  Strain modeling of transpressional and transtensional deformation , 1994 .

[51]  D. Jiang,et al.  Kinematics of rock flow and the interpretation of geological structures, with particular reference to shear zones , 1995 .

[52]  John G. Ramsay,et al.  The techniques of modern structural geology , 1987 .

[53]  A. Cruden,et al.  Strain and vorticity patterns in ideally ductile transpression zones , 1994 .

[54]  B. Tikoff,et al.  Extended models of transpression and transtension, and application to tectonic settings , 1998, Geological Society, London, Special Publications.