Travel through deep time
100 Ma
Ma = million years ago. Older reconstructions have greater uncertainty. MERDITH2021 uses a paleomagnetic reference frame, so deep-time longitude is less constrained.
What this means
The geology layer shows the mapped surface unit at the clicked location. It does not tell you what rock is at foundation, tunnel, aquifer, or well depth. Paleoposition is a plate-model reconstruction, not a measured historical coordinate. Model uncertainty grows deeper in time.