It also should be noted that "21 tons" is an estimate by China Earthquake Networks Centre [1], so it can be deliberately understated. [1] http://www.theguardi

It also should be noted that "21 tons" is an estimate by China Earthquake Networks Centre [1], so it can be deliberately understated. [1] http://www.theguardian.com/world/2015/aug/12/china-explosion-earthquake-recording-instruments-beijing http://www.theguardian.com/world/2015/aug/12/china-explosion...