The NPDP Earthquake-Dam Mapping application draws upon two primary resources:
- NPDP Dams Directory (Go here to learn more), and
- Earthquake database (overview) comprised of a historic earthquake catalog and real-time earthquake data from the U.S. Geological Survey (USGS)
The real-time earthquake feed is automatically checked every five minutes. Earthquakes of magnitude 4.5 or greater are retrieved and the data for the event is entered into the NPDP Earthquake Catalog database.
Once an earthquake of M≥4.5 is identified, a search is carried out to identify any dams in the NPDP Dams Directory that are located in proximity to the event. The search criterion is a function of earthquake magnitude and epicentral distance. The criterion takes into account the high variability in earthquake ground motions and is intended to identify any dams that would ‘feel’ earthquake motions.
For each dam that is identified the NPDP Dam Incident database is automatically populated with an entry that identifies the earthquake that occurred and the epicentral distance.
The NPDP Earthquake-Dam Mapping Applications (http://npdp.stanford.edu/eq_map_overview) give you a range of tools for searching and mapping earthquakes and the dams that felt those earthquakes, or searching for a specific dam to see all earthquakes ‘felt’ at that dam site.