Alden's Fotothing

Here's what I went to Jenner to see: eclogite. This rock type is what happens to basalt when you push it 30 kilometers down into the Earth and heat it up to around 400 C for a million years or so. It's quite rare at the Earth's surface, but a chunk of it a few hundred meters across popped up amid the rocky glop of the Franciscan subduction complex. The reddish grains are garnet and the blue groundmass is glaucophane.