Earthquake lights are a poorly understood, often disputed phenomenon, where it is reported that lights show up in the sky at or near areas of tectonic stress. The idea of Earthquake lights was challenged hotly by the geological community, and it was not until the Earthquake swarms of 1965/1967 in Nagano, Japan that pictures were taken, and Earthquake lights were accepted by seismological community.
The lights occur during the Earthquake, although some reports have suggested lights before and after tectonic activity. They commonly have a blue-white hue and are the shape of auroras, although a much wider colour spectrum has been reported. In recent years the advancement of home video equipment has meant that many more of these lights are not just being reported they are being filmed too, and there are many great videos on You Tube.
So how do they occur? Well no one really knows. One theory is that intense electric fields are created piezoelectrically from the tectonic movement of rocks containing quartz, Another theory suggested that tectonic movement interrupts the ionospehere locally and the glowing/lights are an affect of this.
Some Studies have suggested that if we can understand Earthquake lights and their causes, we may be able to predict Earthquakes.
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