Friday 29 October 2010

Spooky deskcrops

This month's Accretionary Wedge asks us to share photos of our favourite deskcrop, with bonus points if it is spooky. As one who moves, often, I have managed not to accumulate a personal collection of rocks, but rather catalogue them appropriately and store them in the collections of which every university I was with when I collected them. However, I have many photos on my computers of my samples. My personal favourite "spooky" rock photo is this back-scatter electron image of a monazite grain. Every time I see it I think I'm looking at the skull of some sort of humanoid creature.

This was one of the many grains in Tasmanian metamorphic rocks analyzed for U-Th-Pb dating for my PhD thesis. Analysis of a point near the optic lobe of the skull of this grain gave an age of 508 +/- 5 Ma for this grain, which is in good agreement with the main Cambrian metamorphism within Tasmania.

No comments: