Orogenic uplift and collapse, crustal thickness, fabrics and metamorphic phase changes: the role of eclogites

  title={Orogenic uplift and collapse, crustal thickness, fabrics and metamorphic phase changes: the role of eclogites},
  author={John F. Dewey and Paul D. Ryan and Torgeir B. Andersen},
  journal={Geological Society, London, Special Publications},
  pages={325 - 343}
Abstract Coesite-bearing eclogites in several deep crustal metamorphic assemblages now exposed in extensionally-collapsed orogens indicate the tectonic denudation of more than 90 km of crustal rocks and pre-collapsed crustal thicknesses of at least 120 km. For mountain ranges and orogenic plateaux up to 5 km in elevation and average crustal densities of about 2.8, crustal thickness cannot exceed about 80 km unless pre-shortening crustal/lithosphere thickness ratios were less than 0.135 or some… 

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