seismographtremorCUSTER, S.D. (AP) – The U.S. Geological Survey says a small early morning earthquake rumbled in the Black Hills.
 
     KOTA radio  reports that sensors detected the quake in Custer State Park near the Black Hills Playhouse and Center Lake at about 2:45 a.m. Thursday.
 
     The location is about 8 miles south of Mount Rushmore, or 20 miles south-southwest of Rapid City.
 
     It registered 3.5 on the Richter scale at a depth of 4 kilometers.
 
     The USGS says it is unlikely that many felt the quake unless they were very close to the epicenter. There are no reports of damage.