Continental fault structure and the shallow earthquake source, Shortening of continental lithosphere: The neotectonics of Eastern Anatolia - A young collision zone, 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, Experimental Rock Deformation - The Brittle Field, The structure and rheological evolution of reactivated continental fault zones: A review and case study, Strike-slip partitioned transpression of the San Andreas fault system: a lithospheric-scale approach, Fault-zone weakening processes along the reactivated Outer Hebrides Fault Zone, Scotland, 1. Terra Nova, 1992. 7 possible paleostress stages operating from the Late Cretaceous to Quaternary were described. These approaches are illustrated by Our study shows that thickness and geometry of the MCT vary spatially along and across strike. This paper is part of the special publication Continental transpressional and transtensional tectonics (eds R.E. A shear zone is a zone in which strain is clearly higher than in the wall rock, and whose margins are defined by a change in strain, typically seen by rotation of preexisting markers or formation of a new fabric (Fig. Diffuse zone of shearing between quartzofeldspathic orthogneiss (right-hand side of photograph) and amphibolite-rich gneisses (left-hand side of photograph) in West Greenland. Fluid influx in the mid-crust has led to reaction softening of the rock aggregate as strong pre-existing phases such as feldspar are replaced by fine-grained, strongly aligned aggregates of weak phyllosilicates. The Red River Fault zone (RRF) is the major geological discontinuity that separates South China from Indochina. The zone is ACKNOWLEDGEMENTS parallel to a complicated shear zone i F. HorvBth, 0. We have used the conceptual framework of shear zones to delineate the structural break of the MCT at different structural levels in Sikkim Himalaya, India, and identified rock units on either of its sides by available protolith signatures. Importance of correct evaluation and determination of sense of shear in ductile shear zones requires precise observation, measurement and skill. Adjacent the shear zone, ptygmatic folds of quartzo-feldspathic veins in gneisses and crenulated cleavages that overprinted earlier schistosity surfaces in the quartz-mica schist also characterised this deformation phase. The clockwise deviation of the. Part of the work is also deals with deeper structure of the crust in the study area on the basis of geophysical indications. Especially the Slovak terminology of porphyroclast systems and boudins has never been formulated throughly. The work describes presence of backthrusts and reverse faults and possible mechanism and time period of their formation. It has been interpreted as a Precambrian suture, as a zone of strike-slip displacement, or as a zone of crustal shortening. Zuleika Shear Zone were visited over a strike length of ~200 km, from Chadwin in the north to Cave Rocks in the south. Inclusions weaker than the bulk material will develop flattening strains. Reactivated faults and shear zones exposed in the deeply exhumed parts of ancient orogenic belts present opportunities to study processes that influence the mechanical properties of long-lived fault zones at different palaeo-depths. Using a lithospheric-scale approach, the transfer of the displacement field from the penetratively deformed mantle to the strike-slip partitioned upper crust necessitates zones of accommodation in the mid- to lower crust, corresponding to the flat-lying detachments that underlie the San Andreas fault system. shear zones requires the innovative use of combinations of support systems such as rockbolts, shotcrete, forepoles and, in some cases, yielding steel sets. The thesis is devoted mainly to structural geology and tectonic research in the Považský Inovec Mts. Comparison with experimental data suggests that this produces a shallowing of the frictional-viscous creep ('brittie-ductile') transition and a substantial reduction in total crustal strength. The model consists of a seismogenic frictional slip regime overlying quasi-plastic mylonite belts wherein shearing is largely accommodated aseismically, due mainly to the changing response of quartz to deformation with increasing temperature. Seismic anisotropy (shear-wave splitting) and teleseismic analyses suggest that the upper mantle in the San Andreas region is thick and largely undeformed to the SW of the San Andreas fault, but thin and intensely sheared in a zone 50-100 km wide beneath the NE region of the San Andreas fault system. 1). When this correction is made assuming a strike-slip partitioned transpression model, contraction estimation from cross-sections is consistent with both the normal and tangential movements imposed by plate motion: there is no San Andreas discrepancy. 1A) (e.g., Sauber et al., 1994; Dixon et … Late arching and/or tilting of the region in which the shear zone resides has modified the original orien- tation and form of the shear zone even further. 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