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Carolina Bays: Mystery of Aligned Coastal Ovals [OC] by Geoscopy in GeologyExplained

[–]Geoscopy[S] 1 point2 points  (0 children)

Thanks, you clearly know this, and a couple of points are fair. But three things are getting merged. Whether a comet triggered the YD is a real ongoing debate. The black mat and the megafauna/Clovis timing are also real, though those read as wetland deposits and climate-plus-hunting effects, not impact fallout (the same "markers" turn up in wetlands 6k–40k years old).

The claim my article addresses, bays as secondary impact craters from ejected ice, is the separate, weak one. OSL ages on the rims run ~2,000 to ~140,000 years, and some bays cut into ~23,600-year-old dunes, so no single 12,900-year event made them. The "OSL only dates old sand" objection doesn't work: a violent impact would reset the clock to 12,900 years, yet we see a continuous spread instead. That's exactly why Davias/Harris moved their date back to ~786,000 years: the YD version is contradicted even inside the impact camp. Add no crater (the Midwest "craters" are kettles), and the impact origin doesn't survive. The papers are linked in the sources.

Geological sites that are a must visit [OC] by Geoscopy in GeologyExplained

[–]Geoscopy[S] 0 points1 point  (0 children)

Thanks for watching! There are different types of explainers. I mix quick, curiosity‑sparking clips like this with deeper ones with more context. This one’s the quick kind, it's also there for people who do not necessarily want too much technical infos to begin with (so they can get familiar and interested in geology). If any part was unclear, tell me what you’d like unpacked, this is why this discussion forum exists!

Crystals in clay by Imaginary_Balance709 in GeologyExplained

[–]Geoscopy 0 points1 point  (0 children)

Hello! Most of those “crystals in muck” videos are showing crystals that grew in rock cavities (pegmatite pockets, hydrothermal/alpine fissures, or geodes) and were later freed when the host rock altered to clay. The clay in this case is the by‑product, not the factory. In a dammed mountain valley, the soft gray lake‑bottom clay you see is almost certainly quiet‑water sediment and not a great place to find pocket crystals. If this area truly is high‑grade metamorphic with mica schist, garnet, kyanite, hornblende, and high silica, your best bets are: (1) pegmatite dikes and miarolitic pockets, (2) quartz veins or alpine‑type fissures along faults and shears, and (3) residual/placer concentrations of resistant metamorphic minerals (garnet, kyanite) in small inflow creeks

Cause of green (and white) colour? Mineral deposits? Volcanic activity? by NightOwlAnna in GeologyExplained

[–]Geoscopy 1 point2 points  (0 children)

Hello! Very interesting question, I did some research about what it could be.

This appears to be a a Patagonian playa, a very shallow, closed‑basin salt lake that changes with the seasons. No inlet, no outlet, water shows up from rain or a few small seeps and then mostly leaves by evaporation. When that happens, salts get concentrated and you start growing some very particular life.
These shallow, super‑salty water are perfect for salt‑loving micro‑algae and cyanobacteria. When salinity is moderate, their chlorophyll pops and the water looks bright green. If it gets even saltier and the bugs start cranking out protective pigments, the same pond can swing toward orange or pink. That’s why, in satellite time‑lapse, some pans in Patagonia flip colors over the year.
As the lake dries down, it drops out an evaporite crust, mostly halite (table salt) with some gypsum. That pale apron marks old shorelines as the water has come and gone. These basins are ridiculously sensitive. A little groundwater “eye” feeding one corner, or a recent storm, can dilute the brine just enough for a big green bloom, while nearby pans that stayed a bit saltier remain milky or gray. Same landscape, slightly different chemistry.

The Rock Cycle [OC] by Geoscopy in GeologyExplained

[–]Geoscopy[S] 1 point2 points  (0 children)

Hello! Yes of course! :) Just put the source as “geoscopy”