1650AlisonOrd.pptVIP

Localised Folding  Axial Plane Structures Alison Ord1 and Bruce Hobbs1,2 However, if the embedding medium weakens as the layer deflects or shows other more complicated deformation behaviour then the function F is no longer linear. We now explore the situation where a layering arising from metamorphic differentiation forms oblique to folding multi-layers early in the folding history. Thank you * 1Centre for Exploration and Targeting, Earth and Environment, The University of Western Australia 2CSIRO Earth Science and Resource Engineering, Australia. The structures developed in deformed metamorphic rocks are commonly quasi-periodic although localised and this suggests a control arising from non-linear matrix response is important in many instances. As such these structures add yet another layer of richness to the complexity of the folding process observed in non-linear layered materials. Localised folding with axial plane foliation, Bermagui, NSW, Australia. Photo: Mike Rubenach. Outcrop approximately 0.5m across. Localised folding, Kangaroo Island, South Australia. Outcrop about 1m across. Experimental deformation of layers of cloth (Hall, 1815). Model approximately 1m across Field sketches of folded quartz veins (Fletcher and Sherwin, 1978). Examples of non-periodic folding. Folded quartz/feldspar layers (white) crossed by a metamorphic layering (S-full line) from the Jotun Nappe, Norway. Photo: Haakon Fossen Metamorphic layering (full line) developed obliquely to initial bedding (dashed line) in deformed rocks from Anglesey, UK. Outcrop approximately 1m across. Foliations developed by coupled metamorphic/deformation processes. where x is the distance measured along the layer, P is a function of the mechanical properties of the layer, and F(x) is a function that represents the reaction force exerted by the embedding medium on the layer, arising from the deflection of the layer.? This theory expresses the deflection, w, of a single layer embed