Earthquake light

An earthquake light, also known as earthquake lightning or an earthquake flash, is a reported luminous phenomenon that is said to be associated with tectonic stress, seismic activity, or volcanic eruptions. Reports describe flashes, glows, luminous orbs, sheet-like lights, streamers, and other transient lights observed before, during, or after earthquakes and at varying distances from earthquake sites. Experts differ on whether the reports describe a single real phenomenon, multiple unrelated phenomena, or misidentified natural and artificial light sources, and there is no consensus on a confirmed geological mechanism. Some authors use the term more narrowly for lights reported close in time to seismic events, rather than for unexplained lights merely observed near faults or in earthquake-prone regions. Reports of luminous phenomena associated with earthquakes trace back to ancient historical accounts. Photographs from the 1960s Matsushiro earthquake swarm in Japan have been described as the first photographic records of earthquake lights. Later reports and recordings have accompanied earthquakes in Asia, Europe, and the Americas, though many individual cases remain difficult to evaluate because of limited images, eyewitness uncertainty, coinciding weather, and electrical-grid failures. Proposed explanations have included piezoelectricity, electrokinetic effects, triboelectric or fracture-electrification mechanisms, and rock-stress ionization models. Other reported lights have been attributed to non-seismic causes such as lightning, arcing power lines, or power-grid disturbances.