Richter Scale and the magnitude of the difference it represents

The measurement of the quake intensity on the Richter scale is quite different from other scales. It is measured in log and the base of the log is 31.6. So what would this imply when we compare two quake intensity, say 8 & 9. A magnitude of 9 is about 31000 more bigger than the magnitude of 8. This implies that the quake that recently stuck the north eastern part of India with a magnitude of 6.8 is thousand of times smaller than the one which stuck the Japan which was around 9. Northern India which lies on the Himalayan plate is very fragile because of the tension building under this plate forming a fault line. According to scientists there can be a possibility that this quake is just a miniature and the worse is waiting. So quake resistant buildings, better infrastructure which can withstand quakes of larger intensities are the need of the hour.