Geologists may be close to cracking one of the biggest seismological mysteries in the Pacific Northwest: the origin of a powerful earthquake that rattled seven states and provinces when Ulysses S. Grant was president. Preliminary evidence points to a newly discovered fault near the town of Entiat in Chelan County, Wash. The find adds to a growing body of evidence that Central and Eastern Washington are more quake-prone than previously thought, and will help refine seismic risks in an area that's home to 1.5 million people, more than a dozen hydropower dams and the Hanford nuclear reservation, said Craig Weaver,...