Sixteen states are at high risk of damaging earthquakes over the next 50 years and certain areas of the United States face a higher threat of temblors than previously thought, a federal geological survey agency said. The findings come from updated earthquake hazard maps that were released by the U.S. Geological Survey on Thursday. The maps are used to help define safe building codes, help emergency responders plan after a quake, and influence insurance rates, the report said. "The cost of inaction in planning for future earthquakes and other natural disasters can be very high, as demonstrated by several recent damaging events across the globe," Mark Petersen, chief of the USGS National Seismic Hazard Mapping Project, said in a statement.