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5.10: A4 Mylonite 1

  • Page ID
    11143
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    Outcrop and Hand Sample Photos and Videos

    Click on the image to enlarge.

    This is one continuous outcrop containing mylonite 1 (this page) and mylonite 2 (next page). Can you see the mylonite fabric (looks like a foliation) in the rock? The protolith of Mylonite 1 was probably one of the Cranberry Gneiss units.

    A4-Mylonite-1-A-scaled-1.jpg
    A4-Mylonite-1-B-scaled-1.jpg

    This cut hand sample shows the mylonite texture in more detail.

    Thin Section Photos and Videos

    1st = plane polarized light; 2nd = cross-polarized light.

    Hopefully you can see porphyroclasts (augens) and mylonite texture in the thin section images below. Porphyroclasts are mostly qtz, rusty brown layers are clays produced by shearing.

    A4-Mylonite-1-ppl-4x-300x225.jpg
    S5-Cranberry-xpl-4x-300x225.jpg

    Entire thin section scan. 1st = ppl; 2nd = xpl. 

    A4-mylonite1-ppl-scaled-1.jpg
    A4-mylonite1-xpl-scaled-1.jpg

    This page titled 5.10: A4 Mylonite 1 is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Elizabeth Johnson and Juhong Christie Liu (Virtual Library of Virginia) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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