According to the theory, due to pressure in the rocks oxygen is one of the products of the chemical reactions in the rock. When it is under extreme pressure the oxygen gives off a positive charge which is reflected in readings in the ionosphere. The nature and of the charge, can give an indication of the pressure as it slowly build before a major earthquake. The number of lives save may be hard to imagine, but one of the most frightening aspects of an earthquake at the moment, is the fact that there is literally one minutes notice.