Question: what is the biggest earthquake ever recorded in the united states

title: 1960 Valdivia earthquake
text: There is evidence that a similar earthquake and landslide occurred in 1575 in Valdivia . This earthquake was of similar strength and also caused a Riñihuazo . According to the chronicle of Mariño de Lobera , corregidor of Valdivia in 1575 , a landslide blocked the outflow of the lagoon of Renigua . Several months later in April , it caused a flood . He said that the Spanish settlers had evacuated and waited on high ground until after the dam burst , but many aboriginals died in the flood waters . While the 1575 earthquake is considered the most similar one to the 1960 one it differ in not having caused any tsunami in Japan .