Friday Rocks #42: Mylolisthenite

[caption id="attachment_611" align="aligncenter" width="610"]Charlevoix mylolistelite Charlevoix mylolistelite[/caption]

The injecting mylolisthenite (pale-green rock filling fracture) was created during a meteor impact. It can be found near Charlevoix, Quebec (19T 407510.00 m E, 5260539.00 m N). Find out more about the Charlevoix impact crater in an old upsection post.  Mylolisthenite is a fine grained breccia which contains various clasts in a non-melt matrix (differentiating it from pseudotachylite).

Comments

  1. GalenJanuary 10, 2015 at 8:30 PM

    Wow, I'm a former Sudbury geologist and this is the first time I've heard the term mylolisthenite. We unofficially refer to the Sudbury Breccia as pseudotachylite. Really it is a world class example of an impact breccia whose isotope composition indicates it's the ground up equivalent of what's immediately around it. Sudbury is probbaly the biggest preserved impact structure in the world if you take into account its deeply eroded. Anyways, glad I came across your instagram/blog. Keep up the good work! Climbing pictures are where it's at too.

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  2. Tim SherryFebruary 7, 2015 at 3:05 PM

    Thanks, Galen. On the Charlevoix impact field trip we were told that there are pseudotachylytes at the impact center, but we didn't get the chance to see them. I would love to see the Sudbury impact sometime. Cheers!

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