I think this should clarify a bit: The Richter Scale is logarithmic. That means that the difference between 1.0 and 2.0 is not the same amount as the difference between 2.0 and 3.0. When you go from 1.0 to 2.0, 2.0 is ten times more powerful than 1.0 was. When you go from 2.0 to 3.0, 3.0 is ten times more powerful than 2.0 was. So 3.0 is actually *100 times* more powerful than 1.0 was. The power becomes more and more vast as you work your way up the scale. The Richter Scale goes from 0, with no vibration at all, to 10, which is higher than any known earthquake. 0 - no vibration 1 - microquake, not felt by humans 2 - only machines would detect this level of vibration 3 - minor 4 - humans would feel a tiny bit of movement 5 - buildings would shake a small bit, maybe shift 6 - strong shake, some weak buildings might collapse 7 - very powerful - the San Fran earthquake was 6.9 8 - well built buildings destroyed - the 1906 San Fran earthquake was 8.2 9 - ground itself is moving violently 10 - massive upheavals http://www.bellaonline.com/articles/art27151.asp
