Missouri Geological Survey
Joe Gillman
The Central U.S. is Earthquake Country: The Science Behind EarthquakesHazard PreparednessResponse
Stress accumulation along plate boundaries from tectonic activity, most earthquakes occur at or near plate boundaries.
Plate Boundaries and Earthquakes
Earthquakes also occur in other regions not associated with plate boundaries. These are intraplate quakes. New Madrid Seismic Zone
Plate Boundaries and Earthquakes
Effects of Shaking: Geology Matters
Effects of Shaking: Geology Matters
Shaking intensity varies from area to area depending on the underlying geology. Thicker, soft sediments can amplify earthquake waves.
Floodplain
Bedrock
Soft sediment
amplification analogy:
Jell-O
Effects of Shaking:
Liquefaction, lateral spreading, sinkholes, landslides, ground fissures, groundwater disturbance.
Effects of Shaking:
Liquefaction, lateral spreading, sinkholes, landslides, ground fissures, groundwater disturbance.
Effects of Shaking:
Liquefaction, lateral spreading, sinkholes, landslides, ground fissures, groundwater disturbance.
Effects of Shaking:
Liquefaction, lateral spreading, sinkholes, landslides, ground fissures, groundwater disturbance.
Danger in the Central US: Regional Perspective
Colors show levels of horizontal shaking that have a 2-in-100 (2%) chance of being exceeded in a 50-year period. Shaking is expressed as a percentage of g (gravitational force).
Danger in the Central US: New Madrid Seismic ZoneActivity
1811-1812 Event
Recurrence Interval
Annual Activity
Probability
USGS Fact Sheet 2009–3071
What is the most likely earthquake we can expect today, not in 500 or
1000 years, but today?
Recurrence Intervals for New Madrid Earthquake Events
Impact of a M6.5 earthquake
Impact of a M6.5 earthquake
Impact of a M6.5 earthquake
Impact of a M6.5 earthquake
Impact of a M6.5 earthquake
Impact of a M6.5 earthquake
Impact of a M6.5 earthquake
Impact of a M6.5 earthquake
Impact of a M6.5 earthquake
Unreinforced Masonry construction (URM)
• 500,000 URMs in New Madrid region
• FEMA estimates 90% of casualties from URMs
Integration of geologic and geotechnical data into hazards planning
Integration of geologic and geotechnical data into hazards planning
• Bedrock characteristics• Surficial materials characteristics• Depth to water table• Slope stability
What does geologic characterization have to do with earthquake planning and preparedness?
• Damage prediction
• Emergency route planning
• Construction standards
• Emergency facility placement
• Loss estimation
Post Earthquake Technical Information Clearinghouse
-PETIC-
• Use of science information by EMAs requires interpretation and integration with those operations
• Critical need to document geologic and engineering effects of earthquakes by geologists and engineers
• Relieves overburdened EMA officials from the task of managing “science” requests
Purpose
• Facilitating coherent and methodical investigations of the physical impact of an earthquake
• Collection and assimilation of perishable data
• Single POC for exchange of information between EMs and scientific investigators
•Scientist pool
•Long term data management and archive
Objectives
Function of MGS Earthquake Response Plan
Activation:
• M >4.5 when damage is caused• At the request of SEMA/Public Safety
• Should be operational within 24 hours• Duration will be event dependent
• Located at MGS in Rolla with forward operations established as practical
Missouri PETIC
Additional Information
• Missouri Geological Survey – http://www.dnr.mo.gov/geology
• Central United States Earthquake Consortium - http://www.cusec.org/