As far as I know it was Richardson & England (1979) in a paper called'
Metamorphic consequences of crustal eclogite production in overthrust
orogenic zones, published in EPSL 42, 183-90. They suggested the phrase
'piezothermic array' (p188) to replace 'metamorphic geotherm'
Dr Andy Barnicoat
Group Manager, Mineralisation and Geochemistry
Rock Deformation Research
University of Leeds
Leeds LS2 9JT, UK
Phone +44 113 233 5250
Fax +44 113 245 6233
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