Displacement and strain patterns of extensional orogens

摘要: Rock fabrics that result from displacement in extensional orogens provide a means of identifying geometric models responsible for extension continental crust. Strain compatibility arguments indicate finite can be accommodated by displacements across (1) planar, nonrotating faults or ductile shear zones, (2) zones which rotate above horizontal detachment (the domino model), (3) as horizontally oriented, pure stretching component plastic model). Listric, normal zone geometries may develop the depth dependent change (in model) area loss planar Within framework these various models, effects superposed simple shear, extension, and on rock fabric are investigated. These components, sequentially simultaneously, determine state strain associated with given magnitude tectonic extension. The relationships between expressed graphs foliation dip (or ratio) versus illustrate different components single zone, whereas better regional scale. used field geologists to region measurements ratio orientation fluctuation foliation, distinguish possible data, evaluate influence attitude thickness upon amount displacement. Applications methods illustrated areas metamorphic core complexes Arizona Basin Range province North America Cordillera.