30 November 2016

“Drumsticks” of Islay tillite

Posted by Callan

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One fun thing about examining the Port Askaig Tillite in the field is to find odd-shaped exemplars of the unit lying on Islay’s beaches. My favorites were shaped like wands, or antennae, or perhaps the drumsticks freshly detached from a Thanksgiving turkey… a big clast at one end and then a thin septum of the finer-grained matrix to hang on to:

Here’s an example:

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The shape results from differential weathering of the matrix relative to the large clast. Another example is perhaps even more striking, with an ice-cream-cone morphology:

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I recently learned of a museum in Japan dedicated to rocks that look like faces. Perhaps some Ileach should found a museum dedicated to “drumstick stones”…