At White Sands, all of those conditions were met.

The lakebed sediments along the ancient shore of Lake Otero were fine-grained and cohesive — the kind of material that takes a crisp impression and retains it.

The footprints were pressed deep enough to survive the initial drying process.

The overlying sediments that accumulated after the lake level dropped buried them quickly enough to prevent weathering.

And the erosion that has brought them back to the surface in the modern period is gentle enough — driven by wind removing soft gypsum rather than by water carving channels — to expose the impressions without destroying them.

The result is that the footprint surfaces at White Sands are, in places, extraordinarily well preserved.