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The Grenville Province as a shear zone
Nature, 1977PALAEOMAGNETIC 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, 1986Abstract 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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Shear Zones and Mineralized Fissures [PDF]
, 1987 All researchers recognize the important implication of faulting for the geological setting of the Pechenga region. These were studied in most detail in the Pechenga ore field. According to Gorbunov et al. (1978), the geological structure of the Pechenga ore field was formed in five stages.
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Graphite and Shear Zone Evolution
2016Graphite is one of the most distinctive features of the Macraes deposit. Graphite occurs in schist host rocks as variably matured primary organic matter and as structurally-controlled hydrothermal precipitates. Hydrothermal graphite is particularly enriched in Macraes deposit, in micaceous shears.
Dave Craw, Doug MacKenzie
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Porosity network of a ductile shear zone
Journal of Structural Geology, 1995Abstract The permeability of ductile shear zones is assumed to be significantly higher than that of surrounding undeformed rocks, although lower than that of fracture systems. This assumption, which results indirectly from geochemical mass balance calculations, is checked in this paper by the tomography of the porosity network in a metre-wide ...
Géraud, Yves +2 more
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Large shear zones with no relative displacement
Terra Nova, 2008AbstractIn the Oman ophiolite, the large scale Makhibiyah shear zone, in Wadi Tayin massif was generated with no or little relative motion between the two adjacent blocks, in contrast with what is reported from otherwise similar shear zones in deep crust and upper mantle. This shear zone is asymmetrical with, along one margin an asthenospheric mantle (∼
Nicolas, Adolphe, Boudier, Françoise
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Journal of Structural Geology, 1998
Abstract Although many ductile shear zones are supposed to have developed by approximately simple shear flow, some must have formed under different conditions. A few types of such ‘non-simple shear zones’ have been proposed in the literature such as transpression-, transtension- and stretching-shear zones. This paper presents a full three-dimensional
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Abstract Although many ductile shear zones are supposed to have developed by approximately simple shear flow, some must have formed under different conditions. A few types of such ‘non-simple shear zones’ have been proposed in the literature such as transpression-, transtension- and stretching-shear zones. This paper presents a full three-dimensional
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Wind shears in the meteor zone
Planetary and Space Science, 1968Abstract Records of meteor drifts obtained during the I.Q.S.Y. with the radio-meteor technique have been used to resolve wind shears in the 80–100-km region of the upper atmosphere. Some theoretical aspects relevant to the technique of observation are being dealt with and comparison is made with wind shear data obtained by different methods. Two main
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Kinematic indicators in shear zones
1992Shear 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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Journal of Structural Geology, 1980
Abstract Shear zones may be classified into brittle, brittle-ductile, and ductile shear zones. The geometry and displacement boundary conditions of these zones are established. The geometric characteristics of ductile shear zones relevant to geological studies are described: orientations and values of principal finite strains, rotation, and ...
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Abstract Shear zones may be classified into brittle, brittle-ductile, and ductile shear zones. The geometry and displacement boundary conditions of these zones are established. The geometric characteristics of ductile shear zones relevant to geological studies are described: orientations and values of principal finite strains, rotation, and ...
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