USGS: “Did You Feel It? (DYFI) collects information from people who felt an earthquake and creates maps that show what people experienced and the extent of damage. Report it Here – Tell Us! Find the earthquake you felt, and then tell us about it. Not in the list?  Search and View Past Earthquakes. This search is configured to return only events with DYFI products. You may enter additional search parameters for magnitude threshold, time window, and geographic area..” [This posting was prompted by a mild earthquake early this morning in Maryland. The DC Metro Area has experienced more earthquake activity than you may be aware of so this is a good site to use for national and global information.)