After a few miles of these "peripheral clay patches," as I'll dub them, the Quartzville tour enters a stretch with minimal alteration- there are a few highly altered spots, such as the one I'll be featuring next, but by and large the rocks are fairly fresh. As I mentioned in The August first post, the effects of the hydrothermal alteration in this district are very patchy and discontinuous, especially in the outer portions. Toward the center, it's a more consistent, multi-generational quartz breccia, with multiple episodes of fracturing and silicification, but even there, just a few steps can take you from one rock type to something that appears very different.
Photo unmodified. June 19, 2012. FlashEarth location (uncertain, but looks right, and close).
Is This Your Hat?
10 years ago
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