Could a big earthquake in California, Alaska, or Japan cause earthquakes in Washington or Oregon?
Historical data and theory suggests that earthquakes only provoke other shocks within a limited area around the fault rupture. Distant earthquakes have no direct effect on Washington and Oregon. Earthquakes in California, Alaska and Japan are caused by the interaction of different plates than the earthquakes in the Pacific Northwest. However, the 1992 Landers earthquake in southern California caused an increase in tiny earthquakes in geothermal areas as far away as The Geysers in northern California. • Q: Could bridges collapse due to seismic activity in the Pacific Northwest? A: Yes, even modern bridges have sustained damage during earthquakes, leaving them unsafe for use. More rarely, some bridges have failed completely due to strong ground motion. Several collapsed in the Northridge earthquake in January 1994, even though they had been strengthened. The January, 1995 Kobe, Japan earthquake also caused many bridges to fail. It is important to note that both of these earthquakes produ
