US Geological Survey estimates earthquake magnitude is 6.8

As we've been reporting today's earthquake in Kumamoto was initially recorded at a 7.1 magnitude. And in its most recent update, the Japan Meteorological Agency lists its provisional magnitude value as 7.1. But, the US Geological Survey, external has estimated the quake's magnitude was 6.8. Earthquake magnitude figures are often updated as seismologists obtain and analyse new data. As a result, it can often take days for a consensus to be reached on the best overall estimate of a quake's magnitu