9 May 2014

Friday fold: knuckling under in the Mesilla Valley shale

Posted by Callan Bentley

Here’s a fold I saw in Texas, in the Mesilla Valley shale, close to the contact with the Muleros Andesite at Cristo Rey:

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This is a pretty wild looking fold. Let’s zoom in on the most deformed portion:

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Annotation: white is top of the distinctive, blocky, buckled bed, and black is its bottom side. Red shows brittle fractures in that same bed:

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Looks as if it rolled over on itself and snapped…

Hope you haven’t snapped this week. I’m looking forward to rolling over another semester – today’s the day for my final exams, and then it’s into the first part of the summer: “finishing up long-neglected projects” time.