The Hawaiian Island Chain is a series of eight islands located in the middle of the Pacific ocean, approximately 2,400 miles west of the California coast and 3,850 miles east of Japan
. The chain runs in a northwest-southeast orientation ("\"), with the oldest islands in the northwest, getting progressively younger to the southeast.
Going in order from the northwest, the islands are1:
The chain began forming approximately 70 million years ago as the Pacific tectonic plate
began moving over a hot spot
. A hot spot is a plume of magma
rock that rises from within the Earth and pushes through the tectonic plates, forming volcanoes. In this case, the Hawaiian hot spot remained stationary and the Pacific
plate moved over it towards the northwest. Each time the plate moved to a new area, the hot spot produced another island
This is the reason Ni'ihau is the oldest island, and by the same token, Hawai'i is the newest. In fact, the island of Hawai'i is currently still over the hot spot (feeding its volcanoes
with fresh magma
), though it is slowly moving off of it. True to the hot spot theory, a new Hawaiian island is forming, 35km south of the Big Island
. Already named Loihi
, the island-to-be is slowly building on the seafloor
southeast of Kilauea
. Its top is 3000 feet below the water surface, and will break the surface in the next 10,000 to 100,000 years.
The islands are part of an immense underwater chain of volcanoes that extends more than 6000 km northwest of the Big Island, extending all the way north to the Aleutian Trench. This chain of more than 80 volcanoes consists of two parts: the Hawaiian Ridge (the Hawaiian Islands and Midway Island are a part of this) and more northernly, the Emperor Seamount Chain. All of these volcanoes were produced by the hot spot as the Pacific plate slowly moved over it. The amount of lava erupted to form the Hawaiian-Emperor chain is calculated to be at least 750,000 cubic kilometers -- more than enough to blanket the entire state of California with a layer of lava roughly 1.5 km thick.
1I have listed the islands as they are traditionally spelled (with glottal stops) but linked them without apostrophes for easy searching. See Hawai'i for more information.
2Another way to think about this is to visualize the iceberg hitting the Titanic. As the ship passed, the stationary iceberg punched holes in the hull, the oldest ones in the front (first to hit), the newest in the back.
Some of the statistics obtained from the US Geological Survey