Olami–Feder–Christensen model

Summary

The Olami–Feder–Christensen model is a lattice model of earthquakes. Each site carries a stress that grows slowly and is partly passed to its neighbours when it reaches a threshold. Its rule is a continuous-valued cellular automaton that keeps only a fraction of the stress in each transfer, so the model is not conservative. It was introduced by Zeev Olami, Hans Feder and Kim Christensen as a simplified spring-block model of a fault. Its avalanche sizes follow a power law over a range of parameters, similar to the Gutenberg–Richter law. So it is a basic test case for self-organized criticality without conservation.