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Earth of fire

Actualité volcanique, Articles de fond sur étude de volcan, tectonique, récits et photos de voyage

Publié le par Bernard Duyck
Publié dans : #volcanic activity, #Tectonics, #Tsunami
Hunga tonga- Hunga Ha'apai eruption- photo Taaniela Kula 14.01.2022 / 5:14 p.m. - TGS / via Matongitonga

Hunga tonga- Hunga Ha'apai eruption- photo Taaniela Kula 14.01.2022 / 5:14 p.m. - TGS / via Matongitonga

Some interesting info on the ongoing eruption at Hunga Tonga-Hunga Ha'apai.(HTHH)

The latest satellite images show the Tongan ash cloud approaching east of Kadavu at 11 p.m. FT. Much of southern Lau is also covered currently. (Fiji Earthquakes & Weather)

HTHH 15.01.2022 / 8:20 p.m. - Doc. WeatherWatch.co.nz

HTHH 15.01.2022 / 8:20 p.m. - Doc. WeatherWatch.co.nz

HTHH - 15.01.2022 - Fiji is currently sandwiched between a developing weather system to the west and a massive ash cloud from the Tonga eruption to the east. - Doctor. Fiji Earthquakes & Weather - one click to enlarge

HTHH - 15.01.2022 - Fiji is currently sandwiched between a developing weather system to the west and a massive ash cloud from the Tonga eruption to the east. - Doctor. Fiji Earthquakes & Weather - one click to enlarge

The massive shock wave from the eruption of the Hunga Tonga volcano today, January 15 (04 UTC) circled the globe at 1100 km/h and crossed Europe 15 hours later. Many weather stations record astonishing pressure changes of 2 to 3 mbar during the passage of several waves.

( Severe weather EU).

HTHH- shock wave velocity calculation - Doc. WeatherWatch.co.nz 15.01.2022 / 8:20 p.m.

HTHH- shock wave velocity calculation - Doc. WeatherWatch.co.nz 15.01.2022 / 8:20 p.m.

HTHH - the shock wave recorded in Slovenia (Europe) at 17,000 km as the crow flies from the eruptive site - Doc. Severe weather EU 15.01.2022 - one click to enlarge

HTHH - the shock wave recorded in Slovenia (Europe) at 17,000 km as the crow flies from the eruptive site - Doc. Severe weather EU 15.01.2022 - one click to enlarge

Evolution of HTHH according to satellite data

The new lands created by the eruption of December 2014-January 2015, and which connected the 2 small islands, are no longer visible on the SkySat / Planet satellite image of 01.15.2022. according to the radar images, the piontes of the islands were partly washed away.

These new lands were added on the edge of the islands and a major depression / intractrateric cliff. The mass collapsed, presumably generating the tsunami.

Hunga Tonga-Hunga Ha'apai - image archive sat. CNES Pleïade 19.01.2015 - one click to enlarge

Hunga Tonga-Hunga Ha'apai - image archive sat. CNES Pleïade 19.01.2015 - one click to enlarge

HTHH- image Sentinel-2 bands 4,3,2 from 02.01.2022 - one click to enlarge

HTHH- image Sentinel-2 bands 4,3,2 from 02.01.2022 - one click to enlarge

HTHH - SkySat/Planet image 15.01.2022 / 2:25 UTC

HTHH - SkySat/Planet image 15.01.2022 / 2:25 UTC

HTHH - Sentinel radar images between 11.12.2021 and 16.01.2022 at 6 a.m. - via Dr. Janine Krippner - one click to enlarge

HTHH - Sentinel radar images between 11.12.2021 and 16.01.2022 at 6 a.m. - via Dr. Janine Krippner - one click to enlarge

A map, created with April 2016 data from the R/V Falkor, by the Global Volcanism Program, showed details of the entire volcanic edifice. Measured on this quick Google Earth overlay, the diameter of the caldera rim is about 6 km. Recent eruptions have occurred on the N and NE sides. The red asterisk corresponds to the 2009 vent.

A map, created with April 2016 data from the R/V Falkor, by the Global Volcanism Program, showed details of the entire volcanic edifice. Measured on this quick Google Earth overlay, the diameter of the caldera rim is about 6 km. Recent eruptions have occurred on the N and NE sides. The red asterisk corresponds to the 2009 vent.

A map, created with April 2016 data from the R/V Falkor, by the Global Volcanism Program, showed details of the entire volcanic edifice. Measured on this quick Google Earth overlay, the diameter of the caldera rim is about 6 km. Recent eruptions have occurred on the N and NE sides. The red asterisk corresponds to the 2009 vent.

Tectonic context of the eruption:

Tonga sits above the Tonga-Kermadec subduction zone, where the Pacific plate is sinking beneath the Australian plate.
In this case, the melting is due to the addition of water, much like how adding salt can melt ice. (Dr. Judith Hubbard)

How does water enter subduction? Well, the subduction plate (the Pacific plate in this case) has been under the sea for tens of millions of years and is therefore soaked like a sponge.
During subduction, the plate gradually heats up, eventually releasing water molecules into the corner of the dominant mantle, which is hot but essentially dry and practically solid. With the addition of H2O (and/or CO2) this changes, and thus a water-rich magma is formed, which is typical of subduction zone volcanoes. (comment by Boris Behncke, INGV volcanologist)

Tectonics Tonga-Kermadec - Dr. Judith Hubbard 15.01.2022

Tectonics Tonga-Kermadec - Dr. Judith Hubbard 15.01.2022

Arc Tonga-Kermadec - Doc. NSF - one click to enlarge

Arc Tonga-Kermadec - Doc. NSF - one click to enlarge

Sources:

- Dr. Judith Hubbard, Dr. Janine Krippner, Boris Behncke

- Berrocoso, M., Torrecillas, C., Jigena, B., & Fernandez-Ros, A. (2012). Determination of geomorphological and volumetric variations in the 1970 land volcanic craters area (Deception Island, Antarctica) from 1968 using historical and current maps, remote sensing and GNSS. Antarctic Science, 24(04), 367–376. https://doi.org/10.1017/S0954102012000193

- Bulletin of the Global Volcanism Network (2015). BVGN, vol. 40, no. 1 (January 2015). http://volcano.si.edu/showreport.cfm?doi=10.5479/si.GVP.BGVN201501-243040

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