Until 1970, Lōʻihi was thought to be an inactive volcano that had been transported to its current location by sea-floor spreading. The seafloor under Hawaii is 80-100 million years old and was created at the East Pacific Rise, an oceanic spreading center where new sea floor forms from magma that erupts from the mantle. New oceanic crust moves away from the spreading center. Over a period of 80-100 million years, the sea floor under Hawaii moved from the East Pacific Rise to its present location west, carrying ancient seamounts with it. When scientists investigated a series of earthquakes off Hawaii in 1970, they discovered that Lōʻihi was an active member of the Hawaiian-Emperor seamount chain.