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Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 CONT

The transition from kyanite to andalusite is known as the andalusite isograd, while the transition from andalusite to sillimanite is called the sillimanite isograd.  2, record 1, English, - sillimanite%20isograd

Record number: 1, Textual support number: 2 CONT

Note that if were making a geologic map, we could draw a line on the map that separates the pelitic rocks containing only Pyrophyllite from those containing Kyanite + Quartz. Such a line (a surface in 3 dimensions) is called an isograd (iso - same, grad - grade). In this case, since it represents the first appearance of Kyanite, we call it the Kyanite Isograd ... If we continue walking along the direction that T & P increased in these rocks during metamorphism, we would eventually come to another place where in the pelitic rocks the mineral assemblage changes. This time the change is from Kyanite + Quartz to Sillimanite + Quartz. Again, we can draw a line on the map that indicates this change in mineral assemblage, this time calling it the Sillimanite Isograd. Just like before, this represents the point on the phase diagram, above, where the geothermal gradient intersected the boundary for the reaction ... Because the sandstone and the limestone do not contain Kyanite, the isograd does not appear in these rocks, but we can still extrapolate its position across the map or outcrop.  3, record 1, English, - sillimanite%20isograd

Record number: 1, Textual support number: 1 OBS

isograd: A line or surface (either imaginary or in a diagram) joining points where the rock originated under the same conditions of pressure and temperature, as indicated by similarity of facies or metamorphic grade.  4, record 1, English, - sillimanite%20isograd

Record number: 1, Textual support number: 2 OBS

sillimanite isograd: term used at Natural Resources Canada - Earth Sciences Sector.  5, record 1, English, - sillimanite%20isograd

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 OBS

Un isograde représente une ligne sur une carte résultant de l'intersection d'une surface isograde avec la topographie. Elle représenterait une réaction métamorphique et serait implicitement diachrone à cause du temps requis pour mobiliser la chaleur, les fluides et les réactions dans les roches.  2, record 1, French, - isograde%20de%20la%20sillimanite

Record number: 1, Textual support number: 2 OBS

isograde de la sillimanite : terme en usage à Ressources naturelles Canada - Secteur des sciences de la Terre.  3, record 1, French, - isograde%20de%20la%20sillimanite

Record 1,  Textual support,  Spanish