Hawai'i is one of the places where volcanism occurs away from a plate boundary.
This is because of two reasons. Firstly, Hawai'i is situated at a point where the crust
thins to about 5 km; secondly, beneath the Hawai'ian island is a rising plume known
as a hotspot. Although most textbooks theorize that these hotspots remain fixed in position, there is evidence that theHawai'ian hotspot has moved slightly.

Nonetheless, the theory still applies. The Pacific plate moves over the hotspot, and as it does
a volcanic island is formed. But the plate continues to move on, so a chain of volcanoes is generated, the oldest becoming extinct and ultimately being eroded away into a form of
seamount. In the case of Hawai'i, the Pacific plate has moved northwest, and the oldest
(dormant) volcano is Kuaui. The youngest is Hawai'i, and the latest active volcano is Loihi,
off the coast of the main island.

LOIHI

Location 18.92 N 155.27 W
Elev. Below Sea Level 969 m
Loihi is Hawai'i's latest active submarine volcano,
and its most notable eruption was in 1996.

THE EVENTS OF 1996

The largest earthquake swarm ever recorded at ANY Hawai'ian volcano occurred from
17 July 1996. By the end of August, over 4,000 earthquakes had been recorded.
More than 40 of these were between 4 and 5 in magnitude.
There were one, probably two summit eruptions.
Loihi's summit underwent dramatic changes;
A third new pit crater was formed
Significant deposition occurred
Hydrothermic activity was enhanced

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