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Protomylonite

A rock classification type
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A mylonite where less than 50% of the rock volume has undergone grain size reduction.

i. A mylonitic rock produced from contact-metamorphosed rock, with granulation and flowage being due to overthrusts following the contact surfaces between intrusion and country rock.

Ref: AGI

ii. A coherent crush breccia whose characteristically lenticular, megascopic particles faintly retain primary structures. It is a lower grade in the development of mylonite and ultramylonite.

Compare with: ultramylonite.


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Unique IdentifiersHide

Mindat ID:
48670
Long-form identifier:
mindat:1:1:48670:1

Classification of ProtomyloniteHide

Internet Links for ProtomyloniteHide

References for ProtomyloniteHide

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