A
partially eroded pumice cone formed during an eruption that began on
August 7, 2006, is seen from the
north on December 18. By the end of the year wave erosion had destroyed
the cone.
Floating dacitic pumice from this eruption traveled as far as Australia.
Home Reef, a submarine volcano midway between Metis Shoal and Late Island
in the central Tonga islands, was first reported active in the mid-19th
century, when an ephemeral island formed. Eruptions in 1984 and 2006
also formed islands. Photo courtesy of
Royal New Zealand Air Force and Institute of Geological & Nuclear
Sciences, 2006/GVN.
Home
Reef, a submarine volcano midway between Metis Shoal and Late Island in
the central Tonga islands, was first reported active in the mid-19th century,
when an ephemeral island formed.
An
eruption of Home Reef in the Tonga Islands in March 23rd, 1984
produced an island with an
estimated size of 500 x 1500 m and a height of 30-50 m.
A plume to 12 km height was reported during the March 1-5 eruption,
and large amounts of
floating pumice were later encountered by passing ships. Photo by
P.J.R. Shepherd (Royal New Zealand Air Force; courtesy of John
Latter, DSIR, published in SEAN Bull., 1984).
An eruption in 1984 produced a 12-km-high eruption plume, copious amounts
of floating pumice, and an ephemeral island 500 x 1500 m wide, with cliffs
30-50 m high that enclosed a water-filled crater.
An eruption in the vicinity of Home Reef was reported on 2 March at 1107.
Intense submarine activity ejected a plume
to an altitude estimated by an airline pilot at more than 7.5 km. A surface
layer, probably pumice, extended 60 km to the
NE and was 20-30 km wide, enveloping Late Island (25-30 km to the NE).
Surface discoloration of the sea covered
a larger area. Another report at about the same time described a pumice
raft of the same dimensions drifting SW.
Before the eruption had ended, by 5 March at 1030, two small islands had
formed with a maximum elevation of about
20 m, enclosing a crater about 1,500 x 500 m. Island-forming eruptions
of Home Reef occurred in 1852 and perhaps in 1857.
Steam
clouds rise above a new island being built by the eruption at
Home Reef as seen from
the east about 2.8 km away on August 12, 2006. The island at this
time was ~1.5 km in diameter.
The eruption began on August 7 and lasted until about the 16th.
Widespread pumice rafts reached Fiji and as far as Australia.
Photo by Fredrik Fransson, 2006/GVN.
Another island-forming eruption in 2006 produced widespread dacitic pumice
rafts that reached as far as Australia.
Pumice rafts drifting from Tonga to Fiji occurred during August-October
2006. The source of these pumice rafts was Home Reef, which was first
observed to be in eruption on 9 August and was clearly building an island
by 12 August
This
is such a incredible coincidence to be able to actually see this
in the expanse of the Pacific Ocean!
The yacht 'Maiken' is traveling in the south Pacific when they
came across a weird sight...
It was sand in the water and floating ON TOP of the waves... This
is not a beach, it is volcanic stones
floating on the water. And then this was spotted... ash and steam
rising from the ocean...
And, while they were watching... A brand new island formed...
Pretty wild, huh?
The yacht Maiken left Neiafu on 11 August, passing the N side of Late
Island. After about 9 km the crew noticed brown, somewhat grainy streaks
in the water. The streaks became larger and more frequent as they continued
SW "until the whole horizon was a solid line to what looked like
a desert."
An eruption from Home Reef in early August generated large volumes of
pumice that floated to Fiji (over 700 km away)
in the following two months; an island was also created (BGVN 31:09).
Satellite data and imagery have been used to
confirm these observations and provide additional information about
this event
The island built by the eruption from Home Reef in early August was
directly observed on 14 November and 7 December.
The summit of the volcano on 20 November, 2008, was 9-10 m below sea
level, forming a relatively smooth-topped
summit region approximately 500 x 500 m in area
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