The U.S. Geological Survey released a new earthquake hazard map July 17, revealing increased seismic risks for many regions.
Updated for the first time since 2008, the new map incorporates research from the surprising 2011 earthquake in Virginia. With a 5.8 magnitude, it was one of the largest earthquakes to hit the East Coast and helped scientists gauge the possibility of larger events in that area. As a result, the new map concludes that the Eastern U.S. has a higher potential for bigger earthquakes than previously estimated.
While all states have some potential risk for an earthquake, scientists also concluded that 42 states have a reasonable chance of experiencing an earthquake in the next 50 years, which it notes is generally considered the typical lifetime of a building. The map also showed that 16 states are at high risk and have a relatively high likelihood of experiencing damaging ground shaking within the next 50 years.
As in the past, the West remains the most at-risk region for earthquakes. The 16 states with the highest risk include Alaska, Arkansas, California, Hawaii, Idaho, Illinois, Kentucky, Missouri, Montana, Nevada, Oregon, South Carolina, Tennessee, Utah, Washington and Wyoming, according to the report.
With a spike in earthquakes in Oklahoma and other regions of the central United States, researchers are examining whether industrial activities, such as wastewater disposal, are to blame. But no conclusive links have been found.
"Injection-induced earthquakes are challenging to incorporate into hazard models because they may not behave like natural earthquakes and their rates change based on man-made activities," the USGS said.
The government uses the updated report and maps to look at the potential ground shaking levels and does risk analysis based on things like how populated an area is and building construction practices, then considers that information when setting building codes. Local governments also use the information in setting emergency preparedness plans.
In terms of some good news, the new findings slightly lowered the risk of earthquakes in the California locales of Irvine, Santa Barbara and Oakland, as well as in New York City. But if you want to skip earthquakes altogether, head over to North Dakota, Minnesota, Wisconsin and Florida. These states are almost entirely in the "lowest hazard" category of the map.
A full copy of the 2014 update of the National Seismic Hazard Maps may be downloaded (PDF) here.
