Добрый день, Коллеги. Важное сообщение, просьба принять участие. Музей Ферсмана ищет помощь для реставрационных работ в помещении. Подробности по ссылке
The origins of balanced sections lie in the petroleum industry in the 1950's and 19601s, most obviously in Calgary, Canada. The first published balanced sections are those by Bally, Gordy and Stewart 119661 of the Canadian Rockies. The concepts of thrust-terrain structural styles, upon which they are based, have been developing since Peach and Horne's [I9071 classic work on the Moine thrust zone in Scotland. To begin, how can we define a "balanced" section?
Footwall geometry and the rheoiogy of thrust sheets Thrust tectonics in the south central Pyrenees Structural history of high-pressure metamorphic rocks in the southern Vanoise massif, French Alps, and their relation to Alpine tectonic events Development of conjugate shear bands during bulk simple shearing Microscopic deformation mechanisms associated with mica film formation in cleaved psammitic rocks An examination of the cataclastic fabrics and structures of parts of Nisutlin, Anvil and Simpson allochthons, central Yukon: test of the arc-continent collision model Graphic determination of principal stress directions for slickenside populations: an attempt to modify Arthaud's method
Strain partitioning in the Helvetic thrust belt of eastern Switzerland from the leading edge to the internal zone Calcite fabrics in a natural shear environment, the Helvetic nappes of western Switzerland Development of planar and linear fabrics in Dauphinois shales and slates (French Alps) studied by magnetic anisotropy and its mineralogical control Obduction-related planar and linear fabrics in Oman Brittle to ductile transition due to large strains along the White Rock thrust, Wind River mountains, Wyoming Interaction of bed-parallel stylolites and extension veins in boudinage Foreland deformation in the Appalachian Plateau, central New York: the role of small-scale detachment structures in regional overthrusting Cleavage geometry and the development of the Church Bay Anticline, Co. Cork, Ireland The strain and textural history of thin-skinned tectonic zones: examples from the Assynt region of the Moine thrust zone, NW Scotland Strain discontinuities within the Seve-K61i Nappe complex, Scandinavian Caledonides The relation between regionally consistent stretching lineations and plate motions Origin and significance of compositional layering in Late Precambrian sediments, Blue Ridge Province, North Carolina, U.S.A. A probabilistic model for the persistence of early planar fabrics in polydeformed pelitic schists The origin of ribbon lineation within the southern Adirondacks, U.S.A.
Secondary iineation in a high-T quartzite <Galicia. Spain): an explanation for an abnormal fabric
Deformation microfabric development m chalcopyrite in fault zones, Mt. Lyell, Tasmania Fracture controlled feldspar shape fabrics in deformed quartzo-feldspathic rocks Deformation by solution-deposition, and re-equilibration of fluid inclusions in crystals depending on temperature, internal pressure and stress Microstructure and texture in experimentally folded singlelayer rock salt
Two-dimensional strain from the orientatton of lines in a plane
Polyphase late Palaeozoic deformation in the southeastern foreland and northwestern Piedmont of the Alabama Appalachians Fault-related folding in the Ramshorn Peak area, Idaho-Wyoming thrust belt A structural interpretation of a section of the Gavarnie nappe and its implications for Pyrenean geology The Gundahl complex of the New England Fold Belt, eastern Australia: a tectonic m~lange tbrmed in a Palaeozoic subduction complex The generation of ductile and brittle shear bands in a lowangle mylonite zone A study of white mica microstructure and microchemistry in a low grade mylonite Quartz microfabric of the Laxfordian Canisp Shear Zone, NW Scotland Shear bands+ crenulations and differentiated layering in ice-mica models Simulation of deformation of lattices: point-to-point analysis and applications The pole of the Mohr diagram An instrument for teaching clinometry
Finite strain patterns and their significance in Permian rocks of the Alpes Maritimes (France) Microstructural and fabric studies from the rocks of the Moine Nappe, Eriboll, NW Scotland
Incremental deformation and fabric development in a KCl/mica mixture Chlorite-mica aggregates:morphology, orientation, development and bearing on cleavage formation in very-low-grade rocks A possible relationship between augen gneisses and postorogenic granites in S.E. Sweden A new plot to display the strain of elliptical markers Erosion and the mechanics of shallow foreland thrusts Strain analysis of passive elliptical markers: success of destraining methods Secondary cleavages in ductile shear zones Grain size distribution and flow stress in tectonites
The Prina Complex in eastern Crete and its relationship to possible Miocene strike-slip tectonics Strain path partitioning within thrust sheets: microstructural and petrofabric evidence from the Mome Thrust zone at Loch Eriboll, northwest Scotland A geometrical and kinematical approach to the nappe structure in an arcuate foldbelt: the Cantabrian nappes (Hercynian chain, NW Spain) Age, budget and dynamics of an active salt extrusion in Iran Deformation of leucogranites of the crystalline Main Central Sheet in southern Tibet (China) Strain analysis and strain path modelling in the Loch Tollie gneisses, Gairloch, NW Scotland Petrological evidence for the development of refolded folds during a single deformational event
The calculation of a best-fit ellipsoid from elliptical sections on arbitrarily orientated planes Microfracturing in relation to atomic structure of plagioclase from a deformed meta-anorthosite A note on sand dyke orientations On the term 'soft-sediment deformation' An unusual 'crack-seal' vein geometry The relative deformation gradient and its application to cylindrical folds with deformed lineations Balanced cross-sections and their implications for the deep structure of the northwest Alps: discussion Balanced cross-sections and their implications for the deep structure of the northwest Alps: reply Letters to the Editors: The calculation of bulk strain in oblique and inclined balanced sections S--C Mylonites Flow stresses from microstructures in mylonitic quartzites of the Moine Thrust zone, Assynt area, Scotland A method for quantitatively analysing dynamic recrystallization in deformed quartzitic rocks Quartz ribbons in high grade granite gneiss: modifications of dynamically formed quartz c-axis preferred orientation by oriented grain growth Complex synkinematic and postkinematic garnet porphyroblast growth in polymetamorphic rocks Solution transfer syn-Si an inferred means of deriving fault fill in the Lake Moondarra area, Mt. Isa, Queensland, Australia, based on oxygen isotope results Comparison of neutron and X-ray diffraction in texture analysis of deformed carbonate rocks
Mohr circles of the First and Second Kind and their uoe to represent tensor operations Successive development of plane non-cylindrical folds in progressive deformation The curved translation path of the Parpaillon Nappe (French Alps) Thrust tectonics in the North Pyrenees A dislocation model applied to slump structures, Ainsa Basin, South Central Pyrenees Tectonic effects of old very large meteoritic impacts on Earth showing on satellite imagery: a review and speculations Erratum
Genesis of the Batinah m61ange above the Semail ophiolite, Oman Analysis of faulting in porous sandstones Displacement features associated with fault zones: a comparison between observed examples and experimental models Stress and displacement distributions around pyrite grains Interpretation of fracture and physiographic patterns in Alberta, Canada Strain and shape-fabric variations associated with ductile shear zones Dynamic analysis of rough cleavage in the Martinsburg Formation, Maryland Development of early comp6site cleavage in pelites from West Donegal
An understanding of the structural elements in the sub-surface is of great importance when establishing new constructions in bedrock, or surveying areas prone to rockslides. In this thesis the focus has been on combining methods within geology, structural geology, geophysics and engineering geology to reach an interdisciplinary understanding and predict sub-surface structures.
R ock masses deform under the action of forces. Rheology (from the Greek 'study of flow') is the branch of physics dealing with the deformation of materials. An understanding of rheology is a prerequisite for the study of deformed domains. Rheological properties of rocks can be described with or without reference to atomic processes (microrheology and macro-rheology).
The previous chapter dealt with planar geological surfaces. A geological surface which is curved is said to be folded. Most folding is the result of crustal deformation whereby rock layering such as bedding has been subjected to a shortening in a direction within the layering. To demonstrate this place both hands on a tablecloth and draw them together; the shortening of the tablecloth results in a number of folds.
Structural geology is obviously one of the more important subjects for geoscientists working in petroleum industry. Folds and faults in deformed rocks make traps for hydrocarbon accumulation. Also, large-scale deformations, the so-called tectonics, control the architecture of petroliferous sedimentary basins. It is the primary job of a structural geologist to interpret geological map and field data, and infer geometry of large scale folds and faults. However, geoscientists with varied specializations and working with different kinds of data may also be called upon to make structural interpretations.
Folds in ductile shear zones are common structures that have a variety of origins. These can be pre-existing folds that become modified or folds developed during the shearing event. Among the syn-shearing folds, a second subdivision is based on the relative age of the folded surface, which can be pre-existing or newly formed during the shearing event. In each of the three categories final fold geometry and orientation show complex relationships with the kinematic frame. The final fold geometry depends on the vorticity within the shear zone, the rheology and the initial orientation of the folded surface relative to the kinematic framework. It follows that folds are complex structures, difficult to use as kinematic indicators. However, in shear zones where undeformed wall rocks with pre-shear structures are accessible and where kinematics can be well established, folds can provide a valuable natural means to understand the initiation and evolution of structures under non-coaxial regimes. We point to the need of discriminating among different plausible categories, based on the nature of the folded surface and on the inherent structural features of each category. <...>
