A swarm of earthquakes near Sandpoint last April indicates that an ancient fault is active again, a University of Idaho researcher says. The quakes, widely felt in Bonner County, struck April 23 and 24 with magnitudes in the 4.1 to 4.2 range. They were larger than other recent quakes, which allowed scientists to study them in greater detail, said Daisuke Kobayashi, a doctoral student in UI’s geological sciences program. At first, researchers thought the earthquakes occurred along the Hope Fault, a major fault credited for past quakes in the area. But closer scrutiny revealed that the Purcell Trench Fault was responsible, Kobayashi said. “Before the quakes in April, we didn’t know if that fault was active,” he said/Becky Kramer, SR. More here.