Planning to respond to earthquake disasters and strengthening
homes, buildings utility lifelines and communications systems can
greatly reduce the impact of an earthquake.
These measures should be based on the best possible forecast of
the amount and distribution of future earthquake damage. The
amount of damage sustained by a building during a strong
earthquake is difficult to predict and depends on the size, type and
location of the earthquake, the characteristics of the soils at the
building site, and the characteristics of the building itself.
At present, it is not possible to accurately forecast the location or
size of future earthquakes. It is possible however to predict the
behavior of the soil (soil means the relatively loose and soft
geologic materials that typically overlie solid bedrock in the
Northwest) at any particular site. In fact, in many major
earthquakes around the world, a large amount of the damage has
been due to the behavior of the soil.
The Oregon Department of Geology and Mineral Industries has
created maps that identify areas in selected Oregon communities
that will suffer more damage, relative to other areas, during a
damaging earthquake. The analysis is based on the behavior of the
soils, and does not depict the absolute earthquake hazard at any
particular site. It is quite possible that, for any given earthquake,
damage in even the highest hazard areas will be light. On the other
hand, during an earthquake that is stronger or much closer than our
design parameters, even the lowest hazard categories could
experience severe damage.
Learn more about earthquakes on thr Oregon Department of Geology web page.