BackgroundThe oldest of the volcanoes comprising the island of Hawaii, Kohala forms an oval shield constructed along two NW-SE trending rift zones at the NW tip of the island. Large valleys cut into the NE flanks, including the dramatic Waipio Valley, correspond to the headwall region of the massive Pololu debris avalanche that extended 130 km NE. A caldera that apparently formed during the shield stage was buried by post shield lavas. The youngest volcanic series (the Hawk volcanics) are Potassium-Argon age dated between 0.26-0.06 million years ago.
Source: Smithsonian / GVP volcano information
See also: Sentinel hub | Landsat 8