USGS investigates cause of false alarm Shake Alert notice

Bay Area residents received an erroneous 5.9 magnitude earthquake alert Thursday from the USGS Shake Alert system. USGS scientists quickly removed the automated alert about a quake in Dayton, Nevada east of Carson City. The Shake Alert Chief Scientist says it appears the data originated from five sensors in the area, and now scientists are examining whether an algorithm error might be to blame.