Silurian dolomite along the shores of Lake Michigan. Cave Point, Door County, Wisconsin.
Tell me if you’ve heard this one: Two scientists walk into a metal show, and notice that fans behave like molecules in a gas.
Physics! Heavy metal! Also a mosh pit simulator that you can edit the parameters for. Neat.
Petrified tree trunk in Alaska, at a lake a few hours north of Anchorage. Rock hammers for scale; the trunk is also visible on the outcrop about three-quarters of the way up in the middle. The entire area had a ton of little coal seams, petrified wood, and leaf fossils. Scrambling along the near-vertical, highly weathered outcrop above the icy lake also added some spice to the trip.