Day #93 Outcrop: Baked Contact(?), Green Sand Beach

I’ve been trying to find a nice example of a baked contact so that I could jump on the geomeme that Callan and Silver Fox started earlier this week. I thought about maybe using a skarn contact (I think I’ve got pictures of one somewhere), but that’s not exactly aligned with this meme. What I did find I’m not 100% certain qualifies as a baked contact, though I certainly think it might.

These shots are from a ledge above the famous Green Sand Beach near Ka Lae (South Point), Hawaii. My interpretation is that what we’re seeing here is a basaltic lava flow capping the littoral deposits that form the source of the eponymous green sand. This is one of those situations where I took the photos because there appeared to be something geologically interesting going on, even though I wasn’t exactly sure what it was. I’m not certain whether the rusty layer at the contact represents contact metamorphic baking from the lava flow, or later hydrothermal(?) alteration by groundwater, but in any case I think it’s the best I’m likely to do to keep the current geomeme going. Perhaps some more familiar with this locality or these sorts of processes can fill in the details or set the record straight.

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Baked Contact(?), Green Sand Beach

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A Closer Look at the Contact

And of course, the main attraction of this day’s hike was beckoning me to turn around and descend to collect a deskcrop. It’s not easy to linger on an undocumented curiosity when the siren below is singing her song…

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The Green Sand Beach – Eroding Littoral Cone

Explore this and all of my 2010 Deskcrops and Outcrops in Google Earth!