A note on parochial metaphors and culture in science. In the 1990s I was working through a degree in geological science in the U.K. My particular interest was structural geology (deformation of rocks by folding, faulting, etc).

I went on to do a Ph.D., also based in the U.K., in thrust (compressional) tectonics in the French/Swiss Alps. I spent long summers doing fieldwork in the mountains, and wet English winters trying to piece together observations in a computer.

Many of the papers I read were written by North American authors working in the Canadian Rockies. They were abound with analogies with snow and snowploughs piling up snow, in the same way collisions of continents pile up mountains.

This made little sense to me. In Britain we have limited experience of snow, and a snowplough is a vehicle which sprays filthy slush to the side of the road.

These days I live in Norway, and regularly get to rearrange snow. When the conditions are just right, the snow plough (or large shovel-like thing you push by hand) creates these beautiful foreland-propagating imbricate thrust sheets before my very eyes.

Just like the Alps or the Rockies, but much, much, faster.