|
|
|
Probabilities,
Seismic Hazard & Earthquake Engineering
Q: Are earthquake
probabilities or forecasts the same as prediction?
|
| A: No. Probabilities
are estimated from the rate of aftershocks and these are sometimes
confused with the prediction of a particular event. |
Q: What is
the probability that an earthquake will occur in the Bay Area?
|
| A: Within the
next 30 years the probability is 67% that an EQ measuring >6.7
will occur in the Bay Area. |
Q: What is
the probability that an earthquake will occur in the LA Area?
|
| A: Within the
next 30 years the probability is 60% that an EQ measuring >6.7
will occur in Southern California. |
Q: What is
seismic hazard and how is it determined?
|
|
A: Seismic hazard is the hazard
associated with potential earthquakes in a particular area.
For further information, see:
Hazard Maps Help Save Lives and Property
|
Q: How will
my house hold up in an earthquake? Can the USGS send someone
out to evaluate my property?
|
|
A: Published maps will only provide generalized,
uninterpreted information about specific areas. Every property
consists of a unique combination of geologic and structural
factors that must be considered to determine what might happen
to a house during an earthquake. Therefore, an individual
site study is necessary. Geologic factors include: type of
underlying material, depth to bedrock, depth of groundwater,
and slope of land. Structural factors include: materials used
(wood or masonry) in construction, number of floors, design,
and retrofitting present.
As a publicly-funded organization, the U.S. Geological Survey
conducts regional hazard assessments in conjunction with State
and local agencies. We provide information that is used by
planning officials to mitigate hazards. The USGS does not
undertake assessments of individual private property. Site
studies must be arranged by the owner of the property with
geologists or engineers in private practice.
To locate a qualified professional, contact your State government
to determine its certification or licensing requirements for
professional geologists and engineers in private practice.
State boards of registration maintain lists of individuals
who meet requirements established in their State. A local
real estate company may also be able to recommend a qualified
professional.
|
Q: How are
engineers working to make roads and buildings safer?
|
|
A: Earthquake engineers are working
to make roads and buildings safer in the event of a major
earthquakes. This includes both improving the design of new
buildings and bridges as well as strengthening older units
to incorporate the latest advances in seismic and structural
engineering. The Federal Emergency Management Agency plays
a central role in funding research and development for the
purpose of mitigating the effects of earthquakes. See:
Earthquake
Mitigation
CUREE
EERI
MCEER
For further information, see:
UC
Berkeley
|
Q: What is
the USGS doing to mitigate and respond to earthquake hazards?
|
|
A: The U.S. Geological Survey
performs the following functions related to earthquake hazard
mitigation:
- Receives, analyzes, maintains, and
distributes data on earthquake activity worldwide. Satellites
link our National Earthquake Information Center in Golden,
Colorado to a network of seismograph stations. These stations,
located throughout the world, are maintained by the U.S.
Geological Survey, State geological surveys, universities,
research institutions, and foreign governments.
- Provides rapid notification of earthquake
events to civil defense and government officials in the
affected area, and to the public through the news media.
- Produces regional assessments of
earthquake hazards in conjunction with State and local governments.
This information is used by: local planners and building
officials in setting appropriate building and retrofitting
standards in an area government and civil defense officials
in planning for disaster recovery professionals conducting
detailed site assessments researchers engaged in basic and
applied research.
- Engages in basic research to learn
more about the nature of earthquake activity.
- Provides education on earthquake
hazards and safety to the public by publishing and distributing
literature, and through a variety of other outreach efforts.
|
Q: How do
I decide whether or not to get earthquake insurance?
|
|
A: You should consider the following
factors when deciding whether or not to get earthquake insurance:
- proximity to active earthquake faults
- seismic history of the region (frequency
of earthquake
- time since last earthquake
- building construction (type of building.
and foundation
- architectural layout
- materials used
- quality of workmanship
- extent to which earthquake resistance
was considered by the designer
- local site conditions (type and condition
of soil
- slope of the land
- fill material
- geologic structure of the earth beneath
- annual rainfall
- value of the building and its contents
- cost of the insurance and restrictions
on coverage (i.e. the deductible).
|
Back to Earthquake FAQ Main
page
|
|
