Volcanoes old and new in New Zealand

Two tidbits from New Zealand:

– A recent survey of volcanoes in the Kermadec Arc north of New Zealand suggest that there is abundant – and recent – undersea volcanism. Scientists from University of Washington (one of my former homes) and Southhampton University (UK) explored a number of submarines volcanoes including Rumble II West, Rumble III and Brothers, which are all located along the same arc of volcanoes as New Zealand’s own White Island and Mt. Edgecumbe. What they found was a change in the shape of Rumble III (1.4 km below the sea surface) since the last survey in 2007 – the summit crater has been filled and the height of the summit cone is almost 100 m shorter! Sounds like that would have been a significant eruption for that sort of physiographic changes to the volcanic edifice. Previous to this, the last known eruption at Rumble III was in 1986, but the only known eruptions are based on hydrophone evidence. They also found abundant “black smokers” on Brothers Volcano. The map of Rumble II West (above) also shows what appears to be a caldera-like feature with a new cone growing in the center. Studies like this always make me wonder how many eruptions occur under the surface of the ocean that go unnoticed.

– If you’re into historical accounts of volcanic eruptions (and who isn’t?), you might enjoy the snippet posted in the Otaga Daily Times from 1909 entitled “Little to fear from Ngauruhoe’s eruption”. Mt. Ngauruhoe (which is really just the youngest vent of Mt. Tongariro) erupted 100 years ago on March 11 (see above), the original articles reports that the eruption was “the finest seen in New Zealand for years.” The eruption in 1909 was one of many of the volcano in the 20th century, explosive eruptions of ash and debris with moderate intensity (VEI 2).
//Below are the comments from the original posting of this article.
doug Says:
March 12, 2009 at 1:33 am e
given the relative proportion of the earth that is covered by water compared to land and the various plate boundaries, should one assume that there are many more underwater volcanoes than those that reach above sea level (continental and island arc)?
gg Says:
March 12, 2009 at 4:50 am e
Do tell, Dr. K! Just want to say that I check the world earthquakes and volcanoes. We have underwater vents in Canada, even. If it’s on the Ring of Fire, and in water, I’d guess there’s a pretty good chance of underwater volcanoes.
New Zealand undersea volcanism at the Eruptions blog « The Volcanism Blog Says:
March 12, 2009 at 8:13 am e
[…] New Zealand undersea volcanism at the Eruptions blog 12 March 2009 Posted by volcanism in New Zealand, current research, geoscience, submarine volcanism. Tags: Kermadec Arc, New Zealand, undersea volcanism, volcano research trackback Dr Klemetti has an interesting post at his Eruptions blog today on undersea volcanism in the Kermadec Arc, north of New Zealand. A study by the University of Southampton and the University of Washington found evidence of a high level of volcanic activity in this area, with the delightfully-named Rumble III volcano having apparently filled in its crater and lost 100m in height since 2007. Eruptions has all the information and relevant links: Volcanoes old and new in New Zealand. […]
Bruce Says:
March 12, 2009 at 1:54 pm e
Wow! that’s almost like Indonesia!
Erik, I just had a thought, do you think the volume of rhyolite produced by the TVZ has something to do with the fact that the plate boundary is actually dissecting (or trying to) the submerged continent of Zealandia? I read one report a couple of years ago that theorized that melt from the plate boundary was being transferred north from the south of the North Island to be pooled under Taupo .. (this was also to explain the absence of volcanism south of Ruapehu) but couldn’t the volume of rhyolite simply be a product of the thickness of the Zealandia continent itself? Does anyone know of any other regions where plate boundaries are actually dissecting a continent (and no, I don’t mean rift scenarios).. Is there any comparable volcanism?
Thomas Donlon Says:
March 13, 2009 at 8:26 am e
Erik,
I’d be interested to link the location of these volcanoes with current earthquakes so that maybe we could get a sense ahead of time which volcanoes may continue to be active – or be in danger of erupting.
Now are all these volcanoes that you are talking about underwater? And how close are they to breaking through to the surface and how dangerous would that be? So if any breaks through to the surface would it pose any threat for worldwide climate? I am thinking anything that might be Pinatubo size or larger. We have gone a number of months with a dearth of meaningful sunspot activity. Even the occasional sunspot now is often tied in with the last sunspot cycle. A few degrees cooler – like what Pinatubo generated on top of a presently cooling off earth may translate into meaningful or substantial cooling.
Bruce Stout Says:
March 13, 2009 at 11:23 am e
To Thomas!
first thanks for your feedback on my post the other day.
The best way to trace the correlation between the earthquakes and these volcanoes is probably still via the USGS earthquakes site and then when one happens click on the link to Google Earth. I know there are plans to put the seabed into Google earth but I haven’t seen anything yet.
There has been a lot of earthquake activity along the Kermadec trench but from what I have seen most of it has been in the subducting Pacific plate rather than volcano related.
I’d like to see comparable studies for up near Tonga because they have positively huge rates of subduction up there and all that material must result in some volcanism someday, me thinks.
NZ is kind of strange because the axis of subduction flips completely along the Southern Alps and this seems to be holding up plate movement. The TVZ is actually a zone of attenuated crust (ie. extensional) like a rift zone but with a subducting plate underneath it providing the oomph. As far as I know this scenario extends up into the Havre trough NNE of NZ:
http://www.teara.govt.nz/EarthSeaAndSky/OceanStudyAndConservation/SeaFloorGeology/5/ENZ-Resources/Standard/2/en

Extremophiles, Volcanoes and You


Folks have been suggesting that life on Earth started near volcanic vents for a long time now (and of course, some people don’t buy it). Whether or not life sprung forth near hydrothermal vents, undersea black smokers or from the head of Zeus, it doesn’t really change the fact that we find organisms living in these places today, expanding what we might consider “habitable” by leaps and bounds. Case and point, researchers from CU-Boulder have recently found a community of micro-organisms happily living near the summit of Volcán Socompa (above) in Chile in the hydrothermal vents. Now, having done field work in the high Andes of Chile (at Volcán Aucanquilcha – say that three times fast), I can attest to the fact that it is as close to working on Mars as you might be able to get on Earth – dry, desolution, mostly lifeless, extreme day/night temperature variations, thin air, the whole nine yards. So, to find these communities shows just how hardy life can be when presented with challenges.
One interesting question not brought up in the article is how quickly might these communities develop. Socompa was last known to have erupted in 5250 B.C. (most likely). This might limit the amount of time for these micro-organisms to take a foothold at the summit of the volcano to at most ~7,000 years. This seems like a pretty reasonable time for life to reemerge after an eruption – the question would be from where did it arrive in a place as desolate as the high Andes of Chile after the eruption. Of course, this also begs the question of whether life like this could exist of Mars, but that is question best left untouched by me. To me, this is just another example of how no matter how destruction we think volcanoes are, life just keeps on coming back for more.
{Hat tip to reader Thomas Donlon for pointing this out to me.}

Eruptions Mailbag #2

I get a fairly steady stream of emails from Eruptions readers, some of which are very worth a post, but sometimes it takes me a while to get around to posting. This is my second attempt to catch up on these mailbag emails. Remember, feel free to email me questions or comments whether you want.

Thanks for the emails!

Ongoing submarine volcanism in the Mariana Islands


For those of you interested in what happens in the realm of submarine volcanism, I can pass on some tidbits I’ve gotten about NW-Rota 1, a submarine volcano in the Mariana Islands (see bathymetry above). Dr. Ed Kohut (Petrogenex), a friend of mine from my days at Oregon State Univ., is currently on a JAMSTEC research cruise in the Mariana Islands, visiting the area about NW Rota-1. He reports:

“We just reached NW-Rota 1. It is still actively erupting. To put that in perspective, it has been observed erupting every time it has been visited since 2003. Today’s actvity is not as vigourous as in past visits, but there are billowing sulfur laden plumes and the summit has increased ~15 meters since the last ROV visit  (in ’06?).”

Seems that this seamount continues to chug away under ~500 meters of seawater. It is most famous for the 2004 eruption that coated an ROV that visited the volcano with ash and molten sulfur during an eruption (all under water). Below is a short video from a 2006 research cruise of the vigorous behavior at the vent called “Brimstone Pit”, which produced the 2004 eruption. You can clearly see the ash, rock and gases being ejected from the vent, all under half a kilometer of seawater!

The big boulders of Tonga


This might not be directly related to a volcanic eruption, but it has been picked up by a lot of news sources, so I thought I’d give it a mention. A report from researchers at University of Texas hypothesize that some very large coral boulders (up to 10 meters tall) that can be found on the shores of Tongatapu are, in fact, tsunami deposits. That is news enough, but they go on to say that the tsunami could have been volcanically triggered (i.e., started by an eruption or volcanic landslide). The corals are ~122,000 years old and a soil has formed on the corals, so the event was likely thousands to tens of thousands years ago.
Of course, in most of the articles, there is little to back up the volcano provenance, but I’m sure they have more evident beyond the fact that Tonga lies in a volcanic arc (Tonga Arc to be specific) in the Pacific Ocean. There are likely quite a few volcanically-triggered tsunami deposits worldwide, but there are also many earthquake-triggered ones as well, so it will be interesting to see what evidence they have for the deposit being from a volcanically-triggered event. If it is, it is evidence for a fairly sizeable eruption in the Tonga Arc in the recent past (well, geologically speaking).

Active undersea volcanism near Fiji

Lobster and Dugong
The western Pacific basin is pockmarked with active and extinct volcanoes related to the subduction of the Pacific plate along almost all of its western boundary. An Australian National University research group recently discovered a pair of undersea volcanoes that would put any good mining geologist into a fit of joy. These volcanoes are spewing volcanic gases underwater that are very rich in metals like copper, lead, zinc and gold. All of these metals like to go into solution in acidic fluids like volcanic gases, and when these volcanic fluids meet the cold (and decidedly less acidic) seawater, they precipitate the metals (amongst other things). We have seen this before at mid-ocean ridges at black smokers.
These undersea volcanoes are by no means unique, but they are rather large (50-km wide, 4000-m tall) and active. Just looking at their morphology (see image above), they look like large shield volcanoes, such as Kilauea or any of the volcanoes (like Cerro Azul) in the Galapagos – just not at the surface yet. The researchers point out that they could be seen as modern analogs to some of the large volcanogenic mineral deposits that are rich in gold and copper (and other metals).
The volcanoes have been dubbed Dugong and, well, Lobster. I can’t wait until the next big eruption of Mt. Lobster!

Underwater volcanism caught in action

Undersea eruption
Most people don’t realize that a majority of the earth’s volcanoes are underwater. That is to say, the mid-ocean ridge system that runs along the bottom of all the major oceans can be considered one big volcano. However, thanks to its location deep underwater, we have only had second- or third-hand evidence of eruptions at mid-ocean ridges or seamounts.
Not any longer according to my graduate alma mater, Oregon State University. An active eruption was captured at Brimstone Pit in 2006, near Guam, by a team looking for hydrothermal activity at the sea’s bottom. The eruption appears to be a very gassy eruption – explosive undersea activity! The research team were able to record the sounds of the eruption from Brimstone Pit (also known by the less sexy name NW Rota-1) and see some of the glowing from the extruded lava (although apparently there wasn’t much lava that they could see). This is an exciting discovery – to catch an undersea volcano in action – because we don’t know much about what happens in large, underwater explosive eruptions, and we know that there are a number of undersea calderas off Japan that might be responsible for some unidentified ash found in Greenland and elsewhere.