Shocked Quartz is also a clue as to an impact...............
Found this today on Carolina Bays:
In 2018, a Russian–American team quietly published a short but stunning report in Experiment in Geosciences that should be front‑page news for anyone following the Carolina Bays mystery. Working with sediments from three Bays about 10 km north of Myrtle Beach, South Carolina, they ran magnetically extracted grains under a Tescan Vega II SEM at the Geophysical Observatory “Borok” of the Russian Academy of Sciences.
What did they see? Pure nickel films coating ilmenite, magnetite, and quartz grains. Microparticles of native metals and alloys. Nanoparticles of pure Ni. All of it locked onto the surface of rounded sand grains as if flash‑welded there by intense heat
https://cosmictusk.com/nickel-films-in-the-carolina-bays-smoking-gun-fired-from-russia/