CUSEC Earthquake Impact Analysis Tool: Disclaimer & Terms of Use

The CUSEC Earthquake Impact Analysis Tool is based on outputs from FEMA’s Hazus loss estimation software, which estimates potential impacts caused by earthquakes and other natural hazards. The tool provides users with a way to visualize, explore, and analyze potential earthquake impacts at the state and county levels.

As such, it is intended for planning purposes only to help emergency planners make informed decisions about potential impacts from various earthquake scenarios. The scenario information and data provided within the tool are based on hypothetical events and best available data.

The following information regarding variables, source data, and limitations of current earthquake modeling software should be considered when interpreting data provided within the tool. 

Earthquake Variables

Because of the many variables associated with earthquakes, the CUSEC Earthquake Impact Analysis Tool should not be used as the definitive predictor of impacts from a given earthquake scenario. Variables that could affect impacts from an earthquake include:

• Epicenter and magnitude
• Depth of the earthquake
• Soil conditions, including depth to groundwater
• Proximity of the epicenter to people, buildings, and infrastructure
• Timing of the earthquake
• Aftershocks or sequence events

Scenario Data

Care has been given to use authoritative sources for earthquake scenarios, ground motions, and other hazard maps presented within the CUSEC Earthquake Impact Analysis Tool. Given the variables previously identified and the hypothetical nature of the scenario data used, the impact analysis results may not be fully representative of what may occur during an actual earthquake event.

Limitations of Hazus

FEMA’s Hazus 6.1 software was used to generate loss estimations for the scenario data included in the CUSEC Earthquake Impact Analysis Tool. Although a powerful tool for assessing potential losses from natural disasters, Hazus has several limitations. These include:

• Default Data: Hazus relies on a generalized dataset and default building inventory, which may not accurately or fully reflect local conditions. Without significant effort to verify and update this data, the accuracy of the loss estimations can vary significantly depending on the quality of the input data.

• Generalizations: Hazus uses broad generalizations for certain aspects of the default inventory (for example: building construction type, replacement values for buildings and infrastructure, soil type, etc.). While these generalizations can be customized to generate more accurate loss estimations, it can be a time-consuming and expensive process to do so.

• Aftershock and Sequence Modeling: It is common after earthquakes for there to be aftershocks which may also cause injuries and damage or further damage previously impacted buildings and infrastructure. Further, some seismic zones such as the New Madrid Seismic Zone, have produced sequenced earthquakes, where there are multiple, high magnitude (e.g. M7.0 or greater) events over a period of time. While not technically aftershocks, these sequenced earthquake events.

Given the nature of earthquake variables, scenario data, and limitations of Hazus, users of the CUSEC Earthquake Impact Analysis Tool should base their planning and assumptions generated accordingly.

Additionally, all data and representations of data obtained from the CUSEC Earthquake Impact Analysis tool are provided without warranty or guarantee of accuracy. The tool is intended for planning and simulation purposes only.

For questions or additional information, contact cusec@cusec.org.