🧪 Geography Tectonics Simulation

This simulation follows one narrow, well-defined slice of tectonics — how a locked transform (strike-slip) fault behaves between earthquakes. Two plates creep past each other at a constant rate, but friction locks the fault down to a chosen locking depth, so the crust above it stores elastic strain instead of slipping freely. A survey fence line crossing the fault bends smoothly according to the same interseismic velocity profile real GPS networks measure near faults like the San Andreas, while a live stress bar tracks the accumulating slip deficit against the fault's strength. When the deficit reaches that threshold — or you trigger it manually — the fault ruptures in a stick-slip earthquake: the fence snaps forward by the released slip, the stress bar resets, and the cycle begins again exactly as Reid's 1906 elastic rebound theory describes.