Algeria, El Asnam: 1980-2016

The El Asnam cluster is named for the town of El Asnam, on the Mediterranean coast of Algeria. On October 10, 1980 a magnitude 7.1 Ms earthquake (known as the El Asnam earthquake) occurred nearby. Since then the town has been renamed "Chlef". About half the 68 events in the cluster are associated with the 1980 El Asnam sequence over the next several years. There is virtually no local-distance arrival time data for events in the 1980s and depth control for these events is based mainly on teleseismic depth phases. For more recent events there is good local-distance station coverage for depth control, as well as calibration of the hypocentroid. The arrival time dataset suffers from the almost complete absence of S phase data at local [...]