A Key to Determine Metamorphic Grades and Major Reaction-Isograds or Isograds in Common Rocks

  • Helmut G. F. Winkler
Part of the Springer Study Edition book series (SSE)


This chapter summarizes some highlights given in previous chapters in order to provide a key for the determination of metamorphic grades and reaction-isograds. High-grade granulitic rocks diagnostic of the regional hypersthene zone are not considered here because they are treated later. Sequences of isograds are indicated by selected mineral reactions in common rocks. A more precise determination of metamorphic grade may be achieved by referring to the details presented in each relevant chapter. Earlier, in Chapter 7, arguments were given for setting up major divisions of metamorphic grade within the large P-T field of metamorphic conditions. These are very-low-grade, low-grade, mediumgrade, and high-grade. With respect to pressure the metamorphic grades have been further subdivided:



Metamorphic Rock Ultramafic Rock Mafic Rock Metamorphic Grade Reaction Curve 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media New York 1979

Authors and Affiliations

  • Helmut G. F. Winkler
    • 1
  1. 1.Institute of Mineralogy and PetrologyUniversity of GöttingenFederal Republic of Germany

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