I'm a geochemist. In the past ten years I've fixed mass spectrometers, blasted sapphires with a laser beam, explored for uranium in a nature reserve, and measured growth patterns in fish ears, and helped design the next generation of the world's most advanced ion probe. My main interest is in-situ mass spectrometry, but I have a soft spot in my heart for thermodynamics, drillers, and cosmochemistry.
Nic, who does not yet have a blog, has asked me to post the following image for Where on (Google) Earth number 204. I'm going to assume the Schott rule is in effect, unless Nic says otherwise. So wait the allotted time, and go hunting. Post location and geology as soon as you surmise them.