Kaʻena Ridge, also referred to as the Kaʻena Volcano, is a submerged remnant of an ancient shield volcano that is to the north of and once comprised the northern section of the Hawaiian Island of Oʻahu.
Kaʻena Ridge | |
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Kaʻena Ridge Location of Kaʻena Volcano in the Hawaiian Islands | |
Highest point | |
Elevation | −3,937 ft (−1,200 m) |
Coordinates | 21°49′19″N 158°46′19″W / 21.82194°N 158.77194°W |
Geography | |
Location | Hawaii US |
Geology | |
Mountain type | Submerged shield volcano |
Last eruption | Pleistocene? |
Kaʻena Ridge was the oldest of the three volcanoes to form Oʻahu and it was also the shortest when it grew out of sea level. It was about 3,000 ft.[1]
Activity from Kaʻena began roughly 5 million years ago.[2][3] Despite being Oʻahu's oldest volcano, it broke sea level 400,000 years after the Waiʻanae did.[2] This is due to Kaʻena being built on a lower sea depth, whereas other Oʻahu volcanoes were built on pre-existing ridges.[3]
Around 3 million years ago, Kaʻena, Waiʻanae and Koʻolau simultaneously emerged. Kaʻena would later submerge below sea level at an unknown date.[2]
In its current state, the crest of the Kaʻena Ridge extends 35–55 km wide and is located 75–100 km northwest of Kaʻena Point, the westernmost tip of Oʻahu.[4] there is a disputed eruption that occurred near the volcano on May 22nd 1956[5]