Results 221 to 230 of about 52,091 (262)

Deformation in a complex crustal-scale shear zone: Errabiddy Shear Zone, Western Australia

Geological Society, London, Special Publications, 2004
Abstract Detailed mapping of four areas representing different geological units with varying formation histories within the crustal-scale Errabiddy Shear Zone shows an apparently simple temporal progression from foliation and mineral lineation development to folding and then to brittle deformation across the shear zone. However, in detail the
Occhipinti, Sandra, Reddy, Steven
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Ductile Shearing in Attur Shear Zone and its Relation with Moyar Shear Zone, South India

Gondwana Research, 2000
Abstract In the eastern part of southern Peninsular India, the charnockitic hills of the Madras block are cut across by the E-W trending Attur shear zone (ASZ) which is characterised by a thick (1 to 1.5 km) phyllonite zone, showing intense mylonitisation due to ductile shearing.
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Maximum entropy and shear strain of shear zone

Mathematical Geology, 1992
The principle of maximum entropy can be used to determine the shear strain in natural shear zones. When the margin of a shear zone is assumed, the principle leads to the truncated exponential distribution of the shear strain. Ifx is the distance remote from the shear zone center, which possesses the maximum shear strain, the shear strain γ (x) is given
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Formation and maintenance of shear zones

Geology, 2006
The processes that initiate and maintain prograde ductile shear zones are not well understood. We have performed shear experiments (γ = 1 to 3) on a fine-grained (100– 150 μm) gneiss (59% quartz, 28% plagioclase, 13% aligned but not interconnected biotite) to determine the evolution of deformation mechanisms that produce dramatic strain weakening and ...
Caleb W. Holyoke,, Jan Tullis
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On mylonites in ductile shear zones

Journal of Structural Geology, 1980
Abstract In this contribution, shear zones are treated as zones of inhomogeneous deformation in which strain softening has occurred. The mylonites which form in ductile shear zones are the softened medium. The development of mylonite microstructures and fabrics are discussed from this point of view.
S.H. White, S.E. Burrows, J. Carreras, N.D. Shaw, F.J. Humphreys   +4 more
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The Romeral Shear Zone

2019
The Romeral shear zone marks the geological boundary between the physiographic Central and Western cordilleras of the Colombian Andes. It demarcates and encompasses the main locus of deformation associated with the amalgamation and geological-structural evolution of the Northern Andean region during the Meso-Cenozoic, although as an ancient plate ...
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Kvalsund shear zone

data associated with Camryn Salo's honours thesis on the Kvalsund Shear Zone, Ringvassøya ...
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The Grenville Province as a shear zone

Nature, 1977
PALAEOMAGNETIC and structural data on the Grenville Province in North America are best explained if the Grenvillian ‘orogeny’ was caused by right-lateral simple shear of the entire Province. Relative displacement of the edges of the belt is estimated at 200–300 km.
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Terminations of ductile shear zones

Tectonophysics, 1986
Abstract We propose a plane strain model for ductile shear zone terminations in rocks that otherwise record no visible shear strain. This model may explain the strain distribution patterns in naturally occurring terminations of shear zone which show, in the XZ plane of finite strain, (1) a decrease in the area of finite strain and in strain ...
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Kinematic indicators in shear zones

1992
Shear zones are fundamental components of all continental margin orogenic belts, irrespective of style or age. They can occur at any depth in the lithosphere and may be cataclastic, transitional, or mylonitic. They dominate much large- and small-scale lithospheric deformation and control the formation and siting of many economic deposits.
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