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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
Vulcano - fumaroles - photo INGV Roma 1 - one click to enlarge

Vulcano - fumaroles - photo INGV Roma 1 - one click to enlarge

At Vulcano, in the Aeolian Islands, the INGV communicates that the fumarolic temperatures on the edge and inside the crater are on average stable or slightly decreasing.
The CO2 flux in the crater area remains at high values. CO2 fluxes at the base of the La Fossa cone and in the Vulcano Porto area remain at medium-high values.
The SO2 flux in the crater area is at a high and slightly decreasing level.
Geochemistry of thermal aquifers: Physico-chemical parameters in Camping Sicilia and Bambara wells
remain stable
Local seismicity: Slight increase in the frequency of occurrence of events of lower frequency (VLP). No earthquake with Ml >= 1.0 was located in the area of ​​the island of Vulcano.
Deformations - GNSS & Clinometry do not show substantial variations
Continuous gravity stations did not record
significant changes during the period under review.

Mean daily and mean weekly flow (respectively black and blue curve) of SO2 emitted by the fumarolic crater field of Vulcano recorded by the FLAME-DOAS network (INGV-OE). The vertical bar indicates the intraday SO2 flux variability. - one click to enlarge

Mean daily and mean weekly flow (respectively black and blue curve) of SO2 emitted by the fumarolic crater field of Vulcano recorded by the FLAME-DOAS network (INGV-OE). The vertical bar indicates the intraday SO2 flux variability. - one click to enlarge

CO2 levels appear to be strongly dependent on the intensity of soil exhalations and meteorological conditions, both highly variable in space and time, which makes the predictability of locally hazardous conditions extremely difficult.

Volcanic gases therefore continue to pose a danger to the resident population of the city of Vulcano Porto.

 

Source: INGV OE weekly bulletin on 16.01.2022 (issued on 18.01)

Piton de La Fournaise - main thermal anomalies at the eruptive cone measured on 01.19.2022- OVPF & al.

Piton de La Fournaise - main thermal anomalies at the eruptive cone measured on 01.19.2022- OVPF & al.

A field mission, post-eruption, carried out on January 19, 2022 at Piton de La Fournaise by OVPF teams, in cooperation with EMZPCOI, BRGM and ONF, and with the assistance of SAG, the PGHM shows that:

The degassing continues on the eruptive site in two main sectors which feed small plumes dispersed by the wind: on the northern edge of the eruptive cone, a fumarolic zone with abundant deposits of yellow sulfur sublimats and on the lava tunnel within the lava field.

No molten material is visible on the surface, neither in the crater nor on the lava field. The measurements taken on the ground show that the emissions of sulfur compounds (SO2 and H2S) are diluted very quickly with distance from the emission zones.

The main thermal anomalies are located on the edges of the cone and are related to the circulation of hot fluids and within the lava field; there is no significant thermal anomaly near the crater floor.

Piton de La Fournaise - transition to "Vigilance" phase - photo archives B. Duyck

Piton de La Fournaise - transition to "Vigilance" phase - photo archives B. Duyck

Following the observations made by the volcanological observatory of Piton de la Fournaise (OVPF) and the field reconnaissance carried out on January 19, 2022 by the services of the OVPF, the geological and mining research office (BRGM), the National Forestry Board (ONF) and the High Mountain Gendarmerie Platoon (PGHM), the conditions for a partial reopening of the Piton de la Fournaise enclosure have been met. The prefect of La Réunion has decided to return to the VIGILANCE phase of the specific ORSEC system of the Piton de la Fournaise Volcano from Friday January 21, 2022 at 8 a.m.

Access to the upper part of the enclosure remains strictly limited to the following three marked trails:
• the Pas de Bellecombe – Formica Léo – Rivals – Cratère Caubet trail,
• the Pas de Bellecombe – Formica Léo trail – access trail to the Dolomieu crater observation site (access from the north of the crater),
• the Kapor trail to Piton Kapor.

Sources: OVPF-IPGP & Reunion Prefecture 20.01.2022

Mauna Loa's summit caldera, Moku‘āweoweo, photo archives 2019 Civil Air Patrol - USGS HVO - click to enlarge

Mauna Loa's summit caldera, Moku‘āweoweo, photo archives 2019 Civil Air Patrol - USGS HVO - click to enlarge

The Mauna Loa volcano is not erupting.

Seismicity rates remain slightly elevated above long-term background levels, but have not changed significantly over the past week.

Other Mauna Loa monitoring data streams — ground deformation, gas concentrations, visual appearance in webcams — show no significant changes.

Current volcanic alert level: Advisory
Current Aviation Color Code: Yellow.

 

To read : "Mauna Loa - History, hazards, and risk of living with the world's largest volcano" ... or how to prepare for a future eruption on a historical basis:

https://geonarrative.usgs.gov/maunaloa/

 

Source: HVO-USGS

Barren island - image Sentinel-2 bands 12,11,4 from 10.01.2022 - click to enlarge

Barren island - image Sentinel-2 bands 12,11,4 from 10.01.2022 - click to enlarge

The Global Volcanism Program reports based on a Darwin VAAC advisory that between 5 p.m. and 10 p.m. on January 8 and between 12 p.m. and 5 p.m. on January 9, ash plumes from Barren Island reached 1.2 km (4,000 ft) above sea level. and drift W and WSW.

Barren Island, a possession of India in the Andaman Sea about 135 km NE of Port Blair in the Andaman Islands, is the only historically active volcano along the N-S volcanic arc extending between Sumatra and Myanmar.

 

Sources: Global Volcanism Program and VAAC Darwin

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