Tonga’s Metis Shoal may be erupting
Posted by feww on February 3, 2009
Metis Shoal Submarine Volcano May Be Erupting
1. FEWW seismic analysis of Tonga Islands region in south Pacific Ocean (SPO) indicate that Metis Shoal, a submarine volcano located midway between the islands of Kao and Late (about 50 km NNE of Kao), may be about to erupt, or is currently undergoing a period of unrest.
2. Metis Shoal’s last known eruption occurred in 1995, which produced an island with a diameter of about 300 m and a height of 43 m after a solid lava dome was formed above the surface of water in SPO.
3. Since 1851 some 8 episodes of unrest have been recorded. In three, possibly five, of those occasions new islands were created (1858, 1967-68, 1979, 1995).
Metis Shoal
- Country: Tonga
- Region: Tonga Islands, SPO
- Volcano Type: Submarine volcano
- Last Known Eruption: 1995
- Summit Elevation: 43 m asl
- Latitude: 19.18°S 19°11’0″S
- Longitude: 174.87°W 174°52’0″W
4. Metis Shoal, a submarine volcano midway between the islands of Kao and Late, has produced a series of ephemeral islands since the first confirmed activity in the mid-19th century. An island, perhaps not in eruption, was reported in 1781 and subsequently was eroded away. During periods of inactivity following 20th-century eruptions, waves have been observed to break on rocky reefs or sandy banks with depths of 10 m or less. Dacitic tuff cones formed during the first 20th-century eruptions in 1967 and 1979 were soon eroded beneath the sea surface. An eruption in 1995 produced an island with a diameter of 280 m and a height of 43 m following growth of a lava dome above the surface. [Caption: GVP]
5. Waves break over Metis Shoal on February 19, 1968, more than a month after the end of a submarine eruption that began in December 1967 and produced an ephemeral island. Metis Shoal has produced a series of small islands during eruptions observed since the mid-19th century. Most recently, an eruption in 1995 produced a lava dome that built up to 43 m above sea level. Photo by Charles Lundquist, 1968 (Smithsonian Astrophysical Observatory). Caption: GVP
6. Map of the Tonga Islands, showing the island groups and location of Metis Shoal, which re-emerged as an island in June 1995. Source: GVP
Other Photos of Metis Shoal
7. Metis Shoal, sea level view. Source: MTU
8. Metis shoal, aerial view. Source: MTU
9. Metis Shoal aerial photo dated December 7, 2006. Source: GVP
Related Links:
- Global Volcanism Network Bulletin v. 20, no. 6, June 1995 Eruption builds new island
- Metis Shoal: Index of Monthly Reports (GVP)
- Two Volcanoes Erupt in Japan
- Volcanoes [Links page]
- Earthquake Forecast 2009 : Japan
- A New Era of Intense Volcanic Unrest May Have Begun
- Earthquakes [Links page]
Content of this post: 424 words, 9 paras/captions, 5 images, 1 list w/9 bullets
Fire Earth 
edro said
U.S. to upgrade volcano, earthquake monitoring
The U.S. government will spend $15.2 million to modernize equipment for monitoring U.S. volcanoes and improve warning systems, Reuters reported Interior Secretary Ken Salazar as saying on Friday.
“Salazar said $29.4 million will also be spent to double the number of seismic stations that monitor earthquakes across the country to 1,600.”
http://www.reuters.com/article/environmentNews/idUSTRE5392QP20090410
Don’t blame it on the equipment!
Ed Venzke said
What “seismic analysis” has been done that indicated unrest in Tonga?
feww said
FEWW “seismic analysis” refers to a combination of observation, examination and computation of
– Geometric relationships between volcanism and tectonics
– Distribution of volcanic vents relative to the faults and fractures
– Geometric calculations of collisional areas, regional deformation, favored pathways for magma
– Geodynamics of distribution of volcanic vents
– Active tectonic and volcanic features of ongoing land formations
– Morphotectonics and Paleoseismicity of the fault zone
Ed Venzke said
All of which boils down to “We have no data, but are just speculating and making it sound good with the word ‘analysis’ about possible volcanic activity here.” Thanks for clearing that up for me. You really should be more careful when you predict eruptions, or say something is undergoing unrest. Actually having evidence might be a first step.
feww said
Ed – this blog has done extremely well with its forecasts both on volcanism and seismic events. See Kermadec earthquake forecast dated September 30, 2008 at URL: https://feww.wordpress.com/2008/09/30/a-magnitude-7-earthquake-hits-kermadec-islands/
And the actual report dated December 10, 2008 at URL
Has the SI [or anyone else for that matter] ever made a forecast with such [any] degree of accuracy?
Of course not. You have no idea where to begin.
In the case of Metis Shoal the forecast clearly states: “Metis Shoal … may be about to erupt, or is currently undergoing a period of unrest.”
FEWW has no means of verifying whether any activity has occurred recently. However, the forecast is still valid, at least for the next few months [even longer.]
Still, the proximity of Metis Shoal to Hunga Tonga-Hunga Ha’apai [~ 66 nmi] makes the forecast quite unique. Is that what’s bothering you?
Are you upset because unlike FEWW, the Smithsonian has no idea where the next major Earthquake could strike, or a future volcanic eruption may occur?
Afraid we can’t share the model or reveal the methods right now, but the FEWW forecasts are published for everyone to see.
This blog is neither a licensed academic organization, nor an official science journal. The blog has no obligation [or intention] to release any more information than it’s already publishing.
FEWW is endeavoring to introduce a new dimension to earth sciences, and has no time for the “rocky earth” society.
Best wishes – FEWW
msrb said
Doesn’t he sound like another “science” historian phishing for information?
edro said
The ability to hear Earth’s natural rhythms helps hone the scientific focus.