Earthquake or Explosion - Seismic Signal Identification in Eastern Russian using Amplitude Phase Ratios Obtained From Analog Records

Discrimination between earthquakes and chemical explosions is a significantproblem facing many regional seismic networks around the world. Bothearthquakes and chemical explosions are sources of elastic waves; thereforeboth are recorded by seismic networks. In this study various types of Pg/Sgamplitude phase ratios are explored as discriminants to distinguish betweenearthquakes and explosions. Amplitude information from 237 earthquakes(1.5<mb<4.9 10<?<916 km) and 247 explosions (1.4<mb<3.9 6<?<752km) recorded by short period analog seismometers in Eastern Russia wereused to calculate amplitude phase ratios of five different types. These amplituderatios were analyzed separately in two regions: the Yakutia and Magadanregions of Eastern Russia. It was found a tendency of chemical explosionsto have higher values than earthquakes for all types of amplitude ratios studied.The best earthquake-explosion discriminants found for both regionsallow for the classification of 86-92% of the ratios as being either earthquakesor explosions. This book is addressed to geoscientists particularly seismologistsand geophysicists interested in the field of seismic signal identification.