July 23 , 2016. EN. Nevados de Chillan , Copahue , Bagana , Bromo .

Home / Bagana / July 23 , 2016. EN. Nevados de Chillan , Copahue , Bagana , Bromo .

July 23 , 2016. EN. Nevados de Chillan , Copahue , Bagana , Bromo .

July 23 , 2016.

 

Nevados de Chillan , Chile :

Nevados de Chillan volcanic complex (1-15 July).
The level of activity of the volcanic complex is at:
LEVEL YELLOW: changes in the behavior of volcanic activity – likely time for an eruption weeks / months.

Seven hundred and sixty-six (766) seismic events, among which twenty-nine (29) were related to rock fracturing process were recorded, called volcano-tectonic earthquakes (VT) with a local magnitude (ML) Maximum M 1, 5. The biggest event was located 1.9 km north-northwest of the active crater at a depth of 4.7 km. In addition, seven hundred thirty-seven (737) earthquakes related to fluid dynamics inside the volcano, called long-period events (LP) were recorded. The earthquake LP of greater magnitude was at M 2.5   with a reduced displacement (DRC) of 82 cm2. It stands out several LP type earthquake with magnitude (ML) greater  or equal than M 2.0  who were in the zone of active craters with depths between 4 and 5 km, without effect on the activity of area.

nevados de chillan

According to data provided by four (4) GNSS stations that monitor surface deformation of the volcanic complex, some small-scale variations were observed in the horizontal and vertical components, the calculated rate of displacement does not exceed 0.15 cm / month and 0.2 cm / month, respectively. In turn, the control lines that cross the complex showed a deformation rate of less than 0.2 cm / month. Furthermore, data from the two (2) inclinometers installed around the volcano, show no trends in relation to the internal deformation of the volcano, only small-magnitude variations are observed.

The images obtained by the cameras installed in the region, showed weak pulsatile surface activity , mainly characterized by an emission of white fumaroles associated with a high content of water vapor. It was not observed glow or night explosions during this fortnight.

sulfur dioxide emissions (S02) recorded on the Nevados de Chillan volcano by DOAS team at the Chillan station, located 3 km eastnortheast of the active crater, recorded an average value of 996 ± 641 t / d. Due to the pulsatile nature of the degasification, data show high variability and intermittent recording. However, there is an increase in the amount of valid measurements obtained during the first half, with which it is concluded that the increase in sulfur dioxide emissions from the previous month is registered.

 

nevados de chillan

The images published by the Group Sulphur dioxide (Ozone Monitoring Instrument, http://so2.gsfc.nasa.gov/) and NESDIS (National Environmental Satellite, Data and Information, OMI group, http: // satepsanone .nesdis.noaa.gov) reported no abnormalities in sulfur dioxide emissions.
Thermal radiation released by the MODIS MODVOLC on its website (http://modis.higp.hawaii.edu/) and Mirova (Middle lnfraRed, Observation of volcanic activity) on its website (http: / / www .mirovaweb.it /), surveillance systems that indicate significant changes in surface temperature, reported no heat alert in the volcanic complex region
.

Although the monitoring parameters have shown a tendency to equilibrium, earthquakes records LP of greater depth and breadth, as well as the increase in sulfur dioxide emissions during the last fortnight, suggest a greater dynamic in the magmatic system. This low energy could still affect the surface hydrothermal system allowing the emergence of new phreatic explosions and / or phréatosmagmatic eruptions of currently active craters. Therefore, the volcanic alert remains at yellow LEVEL. An area considered at high risk in the current state included a radius of 2 km around the active craters. Therefore, it is recommended to restrict access to this area.

Source : Sernageomin

 

Copahue , Chile :

The level of activity of the volcano is at:
LEVEL YELLOW: changes in the behavior of volcanic activity – likely time for an eruption weeks / months.

A total of six thousand twenty-eight (6028) seismic events, among which twenty-six (26) were classified as volcano-tectonic (VT) associated with rock fracturing processes were recorded. Similarly, with regard to the events associated with the fluid dynamics under the volcano, it was recorded five thousand nine hundred and nine (5909) long period earthquakes (LP) and ninety-three (93) earthquakes very long period (VLP).
Regarding the VT type of seismicity, local magnitude (ML) were less or equal than M1.6. The most energetic event was located on the northwest side (NW) 5.1 km from the Crater El Agrio with a depth of 1.2 km

 

copahue

In connection with the events related to fluid dynamics, local events LP had magnitudes (ML) less than M1.2 and a reduced displacement (DRC) of 3.0 cm2 while the VLP events had reduced displacement (DRC ) of less than 24.7 cm 2 and a magnitude (ML) of less than M1.1, all located around the crater.
During the month, it was registered a constant tremor, which was decreased in amplitude in the last days and is associated primarily with the release of particulate matter (gas and ash) from the crater El Agrio. It was noted fluctuating values DRC
generally less than 4 cm2, values considered low for this volcano. The dominant frequencies are concentrated in a bandwidth between 0.5 and 2.0 Hz.

Sulfur dioxide emissions (S02) recorded on the DOAS equipment in the Triplets station, located 5 km southeast of the active crater, have a mean value of 1.639 ± 1.548 t / d and a maximum value 8345 t / d, noted on July 6. This value is considered high for this volcano and could be associated with a new intrusion of magma.
During the days when weather conditions allowed the observation of the volcano, IP cameras installed close to the volcano recorded a constant degassing of the active crater El Agrio, presenting most of the time a grayish coloring, highlighting the presence of particles. A glow over the entire period was recorded with specific increases associated with the exhalations of gas at high temperature, and small phreatic explosions.

On July 3, an overview of the volcano with the support of the ONEMI observes that the pyroclastic cone observed in the previous month had a larger than seen previously, reaching a height of 40 m and a diameter of about 50 m. Similarly, ejections of incandescent pyroclastic material with ballistic trajectories reaching heights exceeding 50 m above the emission center are noted. The temperature of the gas emitted ranges from 500 and 900 ° around the cone.

copahue
– Thermal radiation released by the MODIS MODVOLC on its website (http://modis.higp.hawaii.edu/) and Mirova (Middle lnfraRed, Observation of volcanic activity) on its website (http: / / www .mirovaweb.it /), surveillance systems that indicate significant changes in surface temperature, noted thermal alerts associated with the volcano during the day of July 3, with the recording   a maximum of radiative power (GRP ) of 3 MW, value considered low.

The monitoring indicators indicate a decrease in the energy of the eruptive activity in recent days, and the reduction of the signal amplitude of tremor associated with this activity. However, emissions of sulfur dioxide and the constant presence of a constant glow indicates a permanent magmatic activity, with the possibility of further increases in activity affecting areas of the crater. Therefore, the limitation of access to the proximal area is recommended, within 2.5 km of the crater El Agrio and consequently the level of technical alert remains at LEVEL YELLOW.

Source : Sernageomin

 

Bagana , Papua New Guinea:

6.137°S, 155.196°E
Elevation 1855 m

Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 17-18 July ash plumes from Bagana rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted over 90 km W and NW.

 

Le volcan Bagana, en Papouasie-Nouvelle-Guinée. - via GVP

Bagana volcano, occupying a remote portion of central Bougainville Island, is one of Melanesia’s youngest and most active volcanoes. This massive symmetrical, roughly 1850-m-high cone was largely constructed by an accumulation of viscous andesitic lava flows. The entire edifice could have been constructed in about 300 years at its present rate of lava production. Eruptive activity is frequent and characterized by non-explosive effusion of viscous lava that maintains a small lava dome in the summit crater, although explosive activity occasionally producing pyroclastic flows also occurs. Lava flows form dramatic, freshly preserved tongue-shaped lobes up to 50-m-thick with prominent levees that descend the volcano’s flanks on all sides. Satellite thermal measurements indicate a continuous eruption from before February 2000 through at least late August 2014.

 

Source: Centre d’avis de cendres volcaniques Darwin (VAAC) , GVP.

 

Bromo , Tengger Caldeira  , Indonesia :

State of alert level of the volcano Bromo, the 23/07/2016: Waspada
White smoke is recorded, 300m high, moving toward the northwest.

Visual: The weather was sunny, calm winds, the temperature of 9 to 21 ° C, the G.Bromo volcano was clear. White smoke was seen thin, low to medium pressure, thick, coming from the crater, high of 50 to 400 meters above the crater moving toward the northwest.
Seismicity of 07/22/2016:
Tremor: Amplitude: 0.5 to 4mm with a dominant 1mm
1 x event TJ: Amplitude: 11 mm, length: 20 seconds to 59 seconds

 

Bromo

 Recommendations of the PVMBG:
Communities and visitors / tourists / hikers around the G.Bromo, following the alert, are not allowed to enter into the radius of 1 km around the active crater of G.Bromo.

Source : PVMBG

Photo : Oystein Lund Andersen

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