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5.9: A3 Schist

  • Page ID
    11142
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    Outcrop and Hand Sample Photos and Videos

    Click on the image to enlarge.

    These outcrops are only a couple hundred meters down the road from the A3 amphibolite. The schist shows distinctive foliation in outcrop.

    A3-schist-1-scaled-1.jpg
    A3-schist-2-scaled-1.jpg

    The hand sample shows the complex foliation in more detail. Pause the video when I show the side of the rock cut by a rock saw.

    Thin Section Photos and Videos

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

    Hornblende (green-brown in ppl, yellow-orange-blue in xpl), garnet, qtz, plagioclase.

    A3-schist-ppl-4x-300x225.jpg
    A3-schist-xpl-4x-300x225.jpg

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

    This thin section is super interesting! Especially for thinking about deformation events. It was made from the cut side of the hand sample shown in the YouTube video above.

    A3-schist-ppl-scaled-1.jpg
    A3-schist-xpl-scaled-1.jpg

    This page titled 5.9: A3 Schist 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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