 Complete the following phrase:  This was the strongest earthquake affecting Chile since the magnitude 9.5 1960 Valdivia earthquake the most energetic earthquake ever measured in the world, and it was the strongest earthquake worldwide since the 2004 Indian Ocean earthquake and until the 2011 Tōhoku earthquake. It is tied with the 1906 EcuadorColombia and 1833 Sumatra earthquakes as the sixth strongest earthquake ever measured, approximately 500 times more powerful than the 7.0 Mw earthquake in Haiti one month prior 