Paul Dennis edited geology2.tex  over 8 years ago

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evidence The seismic profile and geologic section shown in Figure 2 is taken across the north margin of the platform. The lack of deformation is evident in the section with the present basin topography essentially unchanged from the end of the Visean. Uplift and doming of the platform has resulted in the removal of between one to two km of Namurian and Westphalian sediment. The maximum cover for the platform is therefore somewhere between one and two km with maximum basin depths on the order of five km attained towards the end of the Carboniferous. for the top of the platformevidence  for high pore fluid pressures during the period of faulting with the development of mode I fractures and in places a pervasive mesoscale fracture network. Fracture dimensions range from sub-mm to fault widths of several metres. Fracture and fault vein fill at all the locations is dominated by white, sparry calcite often showing a syntaxial growth pattern with varying degrees of complexity as a result of repeated episodes of movement, brecciation and renewed hydrothermal mineral growth.Dirtlow Rake (GR) is a major WSW-ENE trending strike slip fault lying just to the south of Castleton. The width of the exposed fault is greater than 10m and it has been extensively worked over a greater than 10km length for Pb (galena) and Zn (sphalerite). Hydrothermal calcite occurs as large syntaxial and elongate, sparry crystals. The growth form often exhibits dog-tooth terminations indicative of growth into a void.