Hazard Maps

RAPID-N is capable of estimating on-site hazard parameters away from the source location of the hazard, both for historical or scenario hazards. The parameter estimation is done by using the generic prop-erty estimation mechanism, which allows a wide range of estimators to be defined starting from simple equations up to advanced methods. Based on the available input data, the system tries to use the most appropriate methods available in the system for the estimation of the parameters. However, hazard pa-rameter estimation is not the primary aim of the system and therefore its capabilities in this respect are currently limited. In order to make use of the more precise on-site hazard parameter values calculated by advanced models or tools, the system supports the importing of external hazard parameter data in map form. Multiple hazard parameters are supported for each map and on-site values are found by 2-D spatial interpolation. Hazard map records are used to store map data.

The data fields of hazard map records are listed in Table 1.

Table 1. Hazard map data fields

For each hazard map, the natural hazard of interest should be selected from the list of hazards available in the system (Figure 1). The type of the hazard map indicates the format of the hazard parameter data. Currently, three types of hazard maps are supported by the system: ShakeMap XML, ShakeMap XML (Gzipped) and ShakeMap Text XYZ. All these types are used for earthquakes and include tabular PGA, PGV, intensity (MMI), and spectral acceleration (at 0.3, 1.0, and 3.0 s periods with 5% damping) data in regular latitude/longitude grids. Gzipped XML type is the compressed version of XML type with Gzip compression algorithm. Details of the formats can be found in the ShakeMap Manual (Wald et al., 2006). The bounds of the hazard map should be specified. Industrial plants within the map bounds are auto-matically determined by the system and displayed on the hazard map information page together with the bounds (Figure 5.2). Production date and source (as URL) of the hazard map can be indicated and descriptive notes can be entered. Bibliographical references of the hazard map can be cited by selecting required references from the available reference records in the system.

RAPID-N features a web agent application, which periodically follows the ShakeMap RSS feed of the USGS (USGS, 2011a). If a new ShapeMap is published for an earthquake that is found in the RAPID-N database, it is automatically downloaded in XML format and stored in GZipped format. For each Shake-Map a hazard map record is created and the ShakeMap is made available for natech risk assessment purposes. The agent uses date, source URL, and notes fields to store meta-data on the downloaded ShakeMap (Figure 1).