isograd

American  

[ahy-suh-grad] / ˈaɪ səˌgræd /

noun

• isograds
  plural

1. an imaginary line, or one drawn on a map, connecting all the points on Earth where metamorphism of rocks happened under roughly the same temperature and pressure conditions.

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isograd Scientific  

/ ī′sə-grăd′ /

1. A line on a map connecting points on the Earth where metamorphism of rocks occurred under the same pressure and temperature conditions. These lines are established on the basis of the distribution of index minerals and are useful in reconstructing the tectonic history of a given region.

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Other Word Forms

Noun Inflected Forms

• isograds
  plural