Overblog
Editer l'article Suivre ce blog Administration + Créer mon blog

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 : #Actualités volcaniques
Agung - ash plume from 04.07.2018 / 12:20 local - photo Sudiana Wayan

Agung - ash plume from 04.07.2018 / 12:20 local - photo Sudiana Wayan

The seismicity of the Agung is dominated by low frequency earthquakes, consistent with an effusion and an open system.

The surface activity remains dominated by eruptions and ash emissions, as described yesterday 4 July at 12:20, accompanied by a plume rising to 2,500 meters above the summit; it lasted 1 minute 58 seconds, with an amplitude of 24 mm on the seismogram.

The flux of magmatic sulfur dioxide remains high, with 1,400 - 2,400 tonnes / day on 3 July, and 400 - 1,500 tonnes / day on 4 July.

The satellite images indicate ongoing effusive activity, with a dome growing by 4 to 5 million m³ last week, giving a total volume of 50% of the empty volume of the crater.

Source: PVMBG
 

Gunung Agung with Eruption and forest fires. Timelapse video, recorded at 7 am in Amlapura and from 11:15 - 15:36 in Datah, Karangasem, Bali. Music by Aleksandr Shamaluev - video Jacqueline Zwahlen - Beautiful panache between 1'24 and 1'50

At Anak Krakatau, Strombolian eruptions continue.

Since June 18, the earthquakes marking the emission of ash (Hembusan / orange) were followed by a few days of earthquakes of eruption (Letusan / yellow)

Aris, from Exploredesa, tells us about bombs issued more than 1,000 meters away, by Strombolian eruptions spaced less than 20 minutes apart, on July 3rd in the evening.

The last VONA, in orange, mentions a rash at 5:33 local time of 40 seconds, an amplitude of 38 mm max. on the seismogram and continuing ash emissions, drifting north.

Source: PVMBG & MAgma Indonesia

Anak Krakatau - Strombolian activity from 03.07.2018 / 21h05 local - photo Aris - Exploredesa

Anak Krakatau - Strombolian activity from 03.07.2018 / 21h05 local - photo Aris - Exploredesa

Anak Krakatau - seismicity during the period April - July 2018; & seismogram of 4-5 July 2018 - Doc. Magma Indonesia
Anak Krakatau - seismicity during the period April - July 2018; & seismogram of 4-5 July 2018 - Doc. Magma Indonesia

Anak Krakatau - seismicity during the period April - July 2018; & seismogram of 4-5 July 2018 - Doc. Magma Indonesia

In the East rift zone of Kilauea, the activity of crack 8 continues; the lava flow underwent temporary blockages on July 3 and 4, which caused overflows of the channeled flow near the Kapoho cone. These overflows towards Kapoho farm and Beach lots have destroyed some houses still spared until then.

Kilauea East rift zone - evolution of blockage of the channelized flow, with lava overflows - USGS pictures 03.07.2018
Kilauea East rift zone - evolution of blockage of the channelized flow, with lava overflows - USGS pictures 03.07.2018

Kilauea East rift zone - evolution of blockage of the channelized flow, with lava overflows - USGS pictures 03.07.2018

Kilauea East rift zone - Massive overflow of 04.07.2018 following the blockage of the lava flow, which is redirected to Kapoha farm and Beach lots - photo Bruce Omori

Kilauea East rift zone - Massive overflow of 04.07.2018 following the blockage of the lava flow, which is redirected to Kapoha farm and Beach lots - photo Bruce Omori

A slight spattering and gas emissions mark a small cone formed on fissure 22; the lava flow no longer glows, and probably stagnates.

Kiluaea East rift zone - fissure 22: spattering and gas emission at the little cone - photo Bruce Omori

Kiluaea East rift zone - fissure 22: spattering and gas emission at the little cone - photo Bruce Omori

Kilauea East - thermal anomalies remain "extreme" - Doc Mirova Modis at 04.07.2018 / 23:45

Kilauea East - thermal anomalies remain "extreme" - Doc Mirova Modis at 04.07.2018 / 23:45

The National Weather Service reports a storm over the active lava field of the rift zone on July 2, producing 1,200 shots in just 7 hours.

The NWS meteorologist says that the volcano played a major role in this stormy episode, being the basis of the emission of Pyro cumulus; the other actor being an air pocket colder than normal at a lower altitude, in relation to a system located 600 km north of Hilo.

Sources: HVO-USGS, Bruce Omori, and National Weather Service (via The Watchers / West Hawaii Today)

East Kilauea - Pyrocumulus and thunderstorms on lava flows - Doc. NWS 02.07.2018

East Kilauea - Pyrocumulus and thunderstorms on lava flows - Doc. NWS 02.07.2018

Clarifications from Brad Scott, volcanologist, about the crater lake on White Island / New Zealand:

Since April-hand powerful sounds from the crater have been heard by visitors; they ceased as the geothermal system adjusted to the new lake.

This lake is filling at a rate of 2,000 m³ per day ... same rate as in 2003-2004, 2007-2008 and 2013.

Previous lakes have drowned active gas mouths and other fumaroles, leading to localized activity of geysering and small geothermal eruptions, with occasional formation of small cones of tuff-debris around the vents.

If current lake filling continues at this rate, dome drowning is expected in 3-4 months.

White Island / NZ - new crater lake 03.07.2018 - photo GNS

White Island / NZ - new crater lake 03.07.2018 - photo GNS

White Island / NZ - new crater lake when it reappears - photo GNS 19.03.2018

White Island / NZ - new crater lake when it reappears - photo GNS 19.03.2018

However, observations during a recent surveillance visit to the island confirmed that volcanic activity remains at a stable and low level, with no sign of increasing volcanic disturbances. Therefore, current observations are consistent with minor volcanic agitation behavior and for this reason we remain at Volcanic Alert Level 1 and aviation color code remains green.

Source: GeoNet - 04.07.2018

Commenter cet article

Articles récents

Hébergé par Overblog