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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
The ongoing eruption at Halema'uma'u, at Kīlauea's summit, is occurring from a number of vents in a complex located in the western half of the crater. The tallest cone in this complex is about 19 meters (60 feet) tall and is shown in this photograph. -USGS photo by L. Gallant dated March 4, 2022 / AVO - USGS - one click to enlarge

The ongoing eruption at Halema'uma'u, at Kīlauea's summit, is occurring from a number of vents in a complex located in the western half of the crater. The tallest cone in this complex is about 19 meters (60 feet) tall and is shown in this photograph. -USGS photo by L. Gallant dated March 4, 2022 / AVO - USGS - one click to enlarge

The Kīlauea volcano is erupting. Its USGS volcanic alert level is at Watch - aviation code: Orange

Over the past week, lava has continued to erupt intermittently from the western vent of Halema'uma'u Crater. All lava is confined within Halema'uma'u Crater in Hawai'i Volcanoes National Park.
Sulfur dioxide emission rates remain elevated and were last measured at around 2,200 tonnes per day (tpd) on March 8, 2022, during eruptive activity.

Summit tiltmeters show several patterns of deflation and inflation over the past week.

Kilauea / Halema'uma'u - HVO thermal webcam from 2022-03-11 / 8:30 PM HST

Kilauea / Halema'uma'u - HVO thermal webcam from 2022-03-11 / 8:30 PM HST

Seismicity is high but stable, with few earthquakes and ongoing volcanic tremors.

Disturbances to a magma or lava body, such as the underground magma reservoir at Kīlauea Volcano's summit or its present-day lava lake, can occur for a variety of reasons, including rising gas pockets or falling wall rocks in a lava lake. When a body of magma or lava is disturbed, the fluid it contains can react by vibrating or lapping in various ways. For decades, scientists have interpreted seismic signals at volcanoes in Hawaii and around the world as evidence of migration or accumulation of underground magma, which can be used to look for signs that may indicate an impending eruption. In recent years, scientists have learned new ways to use these seismic signals to resolve properties of subsurface magmatic systems that might otherwise not be measurable.

The top graph shows a 2013 seismic record of a normal shallow magnitude 2 earthquake that occurred a few miles south of the summit of Kīlauea Volcano. The bottom plot shows a 2013 seismic record of magma resonance after a large boulder broke away from the walls of Halema'uma'u Crater at the summit of Kīlauea Volcano and then touched the surface of the lava lake. Note the different time scales; the normal earthquake only lasted about 20 seconds in total, while each cycle of magma oscillation lasted 40 seconds and the vibrations continued for more than 20 minutes in total. - Doc. USGS / VolcanoWatch

The top graph shows a 2013 seismic record of a normal shallow magnitude 2 earthquake that occurred a few miles south of the summit of Kīlauea Volcano. The bottom plot shows a 2013 seismic record of magma resonance after a large boulder broke away from the walls of Halema'uma'u Crater at the summit of Kīlauea Volcano and then touched the surface of the lava lake. Note the different time scales; the normal earthquake only lasted about 20 seconds in total, while each cycle of magma oscillation lasted 40 seconds and the vibrations continued for more than 20 minutes in total. - Doc. USGS / VolcanoWatch

Note that compared to earthquakes, the movement of magma generally produces relatively slow vibrations, where the ground rises and falls over several seconds or tens of seconds.

 

Source: HVO & USGS – Volcano Watch: Magma chamber music can tell a revealing tale.

Suwanosejima – 11.03.2022 / 9:58 p.m. – ash plume at 1,600 m. above the crater – JMA webcam

Suwanosejima – 11.03.2022 / 9:58 p.m. – ash plume at 1,600 m. above the crater – JMA webcam

The JMA informs the activity status of Suwanosejima from March 7 to March 11 / 15:00.

Active eruptive activity continues at Otake crater on Suwanosejima.
The eruptive plume accompanying the episodes rose to a maximum of 1,700 m above the crater rim.
The large volcanic bombs disperse up to about 400 m from the center of the crater.
Volcanic earthquakes occurred throughout the period.

 

Source: JMA

 Great Sitkin - photo archive 14.01.2022 AVO / Skeehan, Steve - click to enlarge

Great Sitkin - photo archive 14.01.2022 AVO / Skeehan, Steve - click to enlarge

Outpouring of lava from a vent in the summit crater of Great Sitkin Volcano has continued at a slow rate over the past week. Analyzes of satellite radar images collected on February 28 and March 11 suggest a slightly increased rate of lava effusion during this period, with an advance of the southern lobe of about 65 feet (20 m) and extrusion in all directions around the vent. Most of the flow was covered in snow over the past week except for the front of the lava flow lobes and the portion near the summit vent. Moderately elevated surface temperatures consistent with lava outpouring were detected in satellite data when the volcano was not obscured by cloud cover. The overall level of seismicity was very low.

The erupting lava has overshot the rim of the summit crater and is flowing into small valleys on the southern, western and northern flanks of the volcano. The terrain is steep in these areas, and blocks of lava could break off from the end of the flow lobes without warning and form small rock avalanches in these valleys. Such an avalanche from the flow front of the southern rim of the crater was observed in satellite data from March 7, 2022. These avalanches can release ash and gas and could travel several hundred meters beyond the lava flows; they would be dangerous to anyone in those areas.


Current volcanic alert level: Watch
Current Aviation Color Code: Orange

The Great Sitkin is monitored by local seismic and infrasound sensors, satellite data, web cameras, and remote infrasound and lightning networks.

 

Source: AVO

Galapagos / Wolf volcano - thermal anomalies as of 03.11.2022 / 8:10 p.m. - Doc. Mirova_MODIS_Latest10NTI

Galapagos / Wolf volcano - thermal anomalies as of 03.11.2022 / 8:10 p.m. - Doc. Mirova_MODIS_Latest10NTI

In Galapagos, thermal anomalies are still reported at Wolf Volcano on March 11, 2022: The FIRMS system recorded 91 thermal alerts. The MIROVA system recorded 2 moderate thermal alerts, 1 high (471 MW) and 1 very high (1840 MW).

In the MOUNTS system, 31.8 tonnes of SO2 were recorded, with data from March 10.
Seismicity comes down to a single Volcano-tectonic earthquake (VT)
Thanks to the images provided by the GOES-16 satellite, we can see the thermal anomalies caused by the advance of the lava, as well as the weak columns of gas coming from the flows and the wind.

 

Source: IGEPN

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