Resumen de The curious case of the 1919 Swaziland earthquake
The locations of seismic events during the early twentieth century were sometimes plagued by mislocations, especially in Africa where there were few seismograph stations. In this regard, it is common to find false earthquakes erroneously listed among true ones. Without critical assessment, such events, especially in historical catalogs, have remained in subsequent earthquake catalogs including modern ones. A number of these false earthquakes have been disclosed and their nature revealed and discussed in many places around the world (e.g., Giardini and Balassanaian, 1997; Albini et al., 2010; Grunthal and Walhstrom, 2011). The most difficult catalog records to identify and expose as false events are mislocated true earthquakes (e.g., Guidoboni and Ferrari, 1986; Bellettati et al., 1993; Stucchi and Camassi, 1997; Glavcheva, 2004; Grünthal, 2004; Albini, 2011). These mistakes can only be identified and corrected by reviewing earthquake catalogs starting from the most recent tracing back to earlier studies for reinterpretation (Camassi, 2004; Albini, 2011). The combination of felt effects and instrumental data has helped in the relocation of some earthquakes and in some instances, in the discarding of mislocated earthquakes.
The case of the 31 October 1919 Swaziland earthquake (Ms 6.5) is one example of a false earthquake found today in the catalog for Africa. The event was reported in the International Seismological Summary (ISS) bulletin with phases from 22 stations around the globe but was not reported in the popular media at the time, with no records of it having been felt even in the epicentral area. With the presence of missionaries, British agents, and many reporters in the region at that time, the lack of felt reports for this event raises the question "Did the event really occur in Swaziland or was this epicenter a mislocation?" Another event of...
