Showing papers in "Journal of Structural Geology in 1992"

TL;DR: In this paper, the authors used optical and TEM microscopy to identify three regimes of dislocation creep in experimentally deformed quartz aggregates, depending on the relative rates of grain boundary migration, dislocation climb and dislocation production.

TL;DR: In this paper, a plane strain model for a fault is presented that takes into account the inelastic deformation involved in fault growth, and the model requires that the stresses at the tip of the fault never exceed the shear strength of the surrounding rock.

TL;DR: In this paper, the authors present a synthesis of published data sets on the displacements and lengths of faults, including the geologic setting, the mode of faulting (normal/thrust/strike-slip), and the measurement methods used to obtain the displacement and length data.

TL;DR: In this article, a combined structural and fluid inclusion study on three gold-quartz vein deposits of the Val d'Or area (Abitibi, Quebec) consisting of subhorizontal extensional veins and E-W steeply dipping shear veins is presented.

TL;DR: In this article, an evolution of joint spacing distribution laws from initially negative exponential to log-normal and normal is found with increasing joint development, suggesting that an initiation of fractures according to a random process could explain real joint spacing distributions.

TL;DR: The relationship between the maximum cumulative displacement on a fault (D) and the maximum linear dimension of the fault surface (W) is given by the expression D = cWn, where the value of c is determined by rock properties as discussed by the authors.

TL;DR: In this paper, structural-kinematic analyses of the Caledonides of south Norway show evidence for a crustal extension that is far more widespread and substantial than previously thought.

TL;DR: In this article, two independent estimates of the degree of non-coaxiality during deformation were derived from tectonic features of deformed metachert including both sets of extended and shortened veins and quartz c-axis preferred orientation patterns.

TL;DR: In this article, the authors studied the effect of mechanical interactions between rigid particles on the development of preferred orientations of rigid particles in two-dimensional (2.5D) meshes.

TL;DR: The average rates or durations of processes in shallow to moderate level arc environments are the following: (1) crystal growth rates in magma of 10 −4 cm year −1; (2) growth rates of metamorphic porphyroblasts between 10 −5 and 10 −2 cm year−1 ; (3) long-term magma supply rates of up to 350 km 3 year − 1 ; (4) diapiric ascent rates for mafic plutons of 1 −3 m year −2 ; (5) cooling of pl

TL;DR: In this article, Displacement analysis along 170 mesoscopic faults and 36 mappable faults has been carried out to assess slip rates and to estimate the magnitudes and recurrence time intervals of earthquakes occurring along them.

TL;DR: In this article, the authors show that the joint pattern can reflect perturbations of the regional stress field around faults and that the corresponding joints converge at these points and are sub-parallel to the fault along the remainder of the fault plane.

TL;DR: In this article, the authors examined thrust-related folds exposed in Tennessee, Virginia, Wyoming and Montana that exhibit this geometry and showed that these folds evolved from an initial, brief stage of sinusoidal buckling to a later stage of fixedhinge kinking and thrusting.

TL;DR: In this article, the anisotropy of magnetic susceptibility was measured in 150 samples taken from 11 sites throughout the Vitrollian sequence of the Lagrasse structure (most external Pyrenean Zone).

TL;DR: The Argentine Precordillera (AP) represents a high-level fold-and-thrust belt which was formed during the Andean (Tertiary) crustal shortening.

TL;DR: In this paper, stable isotope systematics of veins and shear zones, as well as variation profiles of chemical elements across major shear zone, distinguish two types of fluid-rock interactions.

TL;DR: In this article, the authors investigated the initiation and development of polydiapirs by means of two-dimensional finite-difference models of gravitationally unstable triple-layered sequences of Newtonian fluids.

TL;DR: In this article, the authors investigated the mechanical interaction between two or more particles in Newtonian simple shear flow, and the experimental models allow observation of both the particle rotation and the deformation pattern around the particles.

TL;DR: In this article, the authors derived a power law distribution with exponents (− S ) of −0.45 to − 0.95 for singleline samples across an array of faults.

TL;DR: In this article, the phase boundary motion and cusp formation occurred during deformation in quartz-feldspar phase boundaries, which is consistent with the accommodation of some intracrystalline plastic strains by dislocation creep.

TL;DR: In this article, the deformation mechanisms and associated growth processes operating in omphacite during foliation development and veining have been studied in a km-scale eclogitic ductile shear zone from the Monviso meta-ophiolitic complex.

TL;DR: In this article, the authors reconstruct the initial configuration of both thin-skinned and deep-seated Oligocene structures that are now locally inverted, and separate the effects of oligocene extension from Liassic extension.

TL;DR: In this paper, a detailed analysis of deformation microstructures associated with a high-level fault in quartzite (Skiag Bridge, Assynt, NW Scotland) reveals a complex variation in the deformation mechanisms active during faulting.

TL;DR: The Coulomb-Navier failure criterion is applied to geological faulting in the general three-dimensional case of rocks containing arbitrarily oriented strength anisotropies and subject to non-Andersonian stress systems.

TL;DR: The Great Slave Lake shear zone as mentioned in this paper is a 25 km wide corridor of granulite to lower greenschist facies mylonites and cataclastic fault rocks developed in the deep-seated parts of an Early Proterozoic (2.0-1.9 Ga) magmatic arc, constructed on the upper (Rae) plate at the contact between the Archean Slave and Rae continents.

TL;DR: Asymmetric competent-layer and foliation boudinage in the Casco Bay area of coastal Maine formed during regional F 2 hinge-parallel elongation and distributed dextral strike-slip movement.

TL;DR: In this article, the authors show that the Alpujarride Complex suffered two shearing episodes defined by different kinematic and physical conditions, which correspond to a deformation in the brittle-ductile transition that led to the thinning of the crust thickened in the previous episode.

TL;DR: The Sumdum-Fanshaw fault system marks the tectonic boundary between the Alexander-Wrangellia terrane and inboard Yukon-Tanana and Stikine terranes and lies within a thrust belt that extends from southern Alaska to northern Washington.

TL;DR: In this article, the authors studied the influence of a pre-existing isolated perturbation in the shape of an otherwise planar layer on the location and shape of folds, and found that the influence is most marked when its average wavelength component is larger than the dominant wavelength (i.e. the wavelength of maximum growth rate).

TL;DR: In the Napperby Gneiss, central Australia, a distinctive group of elongate leucosomes occurs along the axial planes of mesoscopic crenulations that have harmonic, two-dimensional, kink band-like geometries as discussed by the authors.