The 1906 San Francisco earthquake resulted in surface displacement of up to 20 feet near the faultline. Did this lead to any major property disputes? Was there already a legal precedent for handling cases where the land under a property line literally moved on its own?

by hborrgg
jeffbell

The property line disputes were minor. Most areas along the fault had low density land use patterns.

In the 1906 earthquake the fault slipped along a section between Point Arena on the north coast and the San Juan Bautista in the south bay. Following the fault, it passes along the Santa Cruz mountains, under the Crystal Springs reservoirs, and off the coast south of what is now Daly City. It passes through Bolinas Bay, through Olemo and then back underwater. It rises again near Fort Ross and goes back offshore at Point Arena

The largest displacement (~7m) measured was in the Olema Valley, which was mainly used as dairy farm.

The displacement near Daly City was 3m, but again it wasn't really a city at the time. It was John Daly's ranch.

In Fort Ross it runs through an orchard, and then forms the bed of the Gualala river.

There was a flurry of legal activity after the earthquake, but it was mostly centered on collecting/disputing fire insurance policies in San Francisco. There was no anticipation of systemic slippage along the fault until the results were compiled into the Lawson report of 1908.

Luckily since 1972 we have the Cullen Earthquake Act (CA Ch3.16, Sect751.50) which provides the procedures and deadlines for filing for equitable remedies if your property lines have moved.

This is an issue in Berkeley where the Hayward fault is moving steadily at 1cm a year and the results are more visible. From my non-lawyer reading of the law, it requires an even like an earthquake, and doesn't really cover slowly creeping faults.