First of all, it was a 6.1 for Potsdam - check Raw Data for 39 stations :
http://www.freerepublic.com/focus/f-news/1211143/posts?page=129#129
First of all, you need to know a LITTLE about seismic evaluations. Potsdam is where??? indicating that its evaluation is based upon EUROPEAN stations (hint, hint). A tinfoil thread a while back had a EUROPEAN network initially ploted a 6.0 quake off Florida, upon further analysis, the actual location was off the west coast of Mexico. Secondly, I don't think you are qualified to analyze RAW data unless you are a seismologist. Secondly, US and Carribean seismic stations are closer to the epicenter and provide better data as to location and magnitude. The international seismic community recognizes this. Finally, even a 6.1 is still TOO SMALL to do what you are claiming.