Seismic and Infrasonic Analysis of the Major Bolide Event of 15 February 2013

Abstract

Online Material: Tables of moment tensor solutions, station M s estimates, infrasonic signal parameters; figures of velocity models, simulated vertical component displacement time histories and spectra, Green’s functions. A major bolide event causing damage and injuries in a region of the Russian Federation east of the Ural Mountains occurred at approximately 03:20 GMT on the morning of 15 February 2013. The meteoroid entered the Earth’s atmosphere traveling from east‐to‐ west before final disintegration near the city of Chelyabinsk. Widespread damage was reported across the region, affecting more than 7000 buildings in several cities and resulting in injuries to over 1500 persons. Many fragments of the meteorite several centimeters in diameter have been recovered from the region surrounding Chelyabinsk. The meteorite will probably be named the Chebarkul meteorite due to large fragments having been recovered from near Lake Chebarkul, west of Chelyabinsk and near the apparent termination point of the meteorite track (Tauzin et al. , 2013, and references therein). In this article, we will refer to the event as the Chebarkul bolide. During the period of atmospheric traverse the Chebarkul bolide was recorded on infrasonic stations located as far away as Antarctica (Le Pichon et al. , 2013), and the terminal air blast coupled with the solid Earth to generate seismic surface waves visible on broadband seismographs to distances of over 4000 km (Tauzin et al. , 2013). Very few such events are sufficiently energetic to produce well‐observed seismic signals beyond a few hundred kilometers from the source (Yamada and Mori, 2010). The first estimate of the equivalent yield of the air blast by P. Brown of the University of Western Ontario (http://www.jpl.nasa.gov/news/news.php?release=2013-061, last accessed 25 February 2013) was nearly 500 kilotons (kt) of trinitrotoluene (TNT). The event is believed to be the most energetic bolide to have occurred since the 1908 event …