Induced seismicity in Basel
The largest event prompted concern from local residents. The six borehole seismometers installed near the Basel injection well to monitor the natural background seismicity and the geothermal stimulation recorded more than 13,500 potential events connected with the geothermal project, from which 3,124 were of sufficient quality to permit [hypocenter] determinations in the period 2–12 December 2006, which spanned the main stimulation and the decline in the event rate. During the post-stimulation period from 13 December 2006 onward, a further 350 locatable events were detected up to 2 May 2007, by which time events were occurring sporadically at around one per day. In all, locations for more than 3,500 events were determined.
1962 FIFA World Cup
The Valdivia earthquake, the most powerful earthquake ever recorded, occurred on 22 May 1960. With over 50,000 casualties and more than 2 million people affected, the earthquake forced the organising committee to completely modify the World Cup's calendar. Talca, Concepción, Talcahuano and Valdivia were severely damaged and discarded as venues. Antofagasta and Valparaíso declined to host any matches as their venues were not financially self-sustainable. Viña del Mar and Arica managed to rebuild their stadiums while Braden Copper Company, then an American company that controlled the El Teniente copper mine, allowed the use of its stadium in Rancagua. The most used stadium was the Estadio Nacional in Santiago, with 10 matches; the Estadio Sausalito in Viña del Mar hosted 8 matches, and the stadiums in Rancagua and far-away Arica (the only location that was not close to the other cities) both hosted 7 matches.