February 05 , 2018.

 

Mayon , Philippines :

MAYON VOLCANO BULLETIN , 05 February 2018 08:00 A.M.

Sporadic and weak lava fountaining, lava flow and degassing from the summit crater characterized Mayon’s activity yesterday. Two lava fountaining events yesterday produced 500 and 550 meter high ash plumes 10:38 AM and 1:52 PM both observed with rumbling sounds. The first event of these two events, lasting for an hour and fifty four minutes of sporadic lava flows, was accompanied by booming sounds audible within 10 kilometers of the summit crater. Throughout the night, quiet lava effusion fed lava flows in the Miisi and Bonga-Buyuan channels and barrancos between these with the exception of two weak lava fountaining events early this morning at 02:54 AM and 05:22 AM. These events were visually observed to have ejected high volumes of incandescent lava that have advanced to 3.2 kilometers and 4.5 kilometers, through the Miisi and Bonga-Buyuan channels respectively, from the summit crater.

 

A 15 minute long exposure show a star trail, and the full blood moon, over erupting Mayon volcano, near Legazpi city, Philippines.

A total of one hundred sixty four (164) volcanic earthquakes, most of which corresponded to sporadic and weak fountaining events, two (2) rockfall events and one (1) tremor event were recorded by Mayon’s seismic monitoring network. Sulfur dioxide gas emission was measured at an average of 1,583 tonnes/day on 02 February 2018. Electronic tilt and continuous GPS measurements indicate a sustained swelling or inflation of the edifice since November and October 2017, consistent with pressurization by magmatic intrusion.

Alert Level 4 remains in effect over Mayon Volcano. The public is strongly advised to be vigilant and desist from entering the eight (8) kilometer-radius danger zone, and to be additionally vigilant against pyroclastic density currents, lahars and sediment-laden stream flows along channels draining the edifice. Civil aviation authorities must also advise pilots to avoid flying close to the volcano’s summit as ash from any sudden eruption can be hazardous to aircraft.

DOST-PHIVOLCS maintains close monitoring of Mayon Volcano and any new development will be communicated to all concerned stakeholders.

Source : Phivolcs.

Photos : Pablo Squiza , TED ALJIBE.

 

Cumbal , Colombia :

Subject: Cumbal Volcano Activity Bulletin.
The level of activity of the volcano is maintained at the level:
YELLOW LEVEL ■ (III): CHANGES IN THE CONDUCT OF VOLCANIC ACTIVITY

Following the activity of the CUMBAL VOLCANIC COMPLEX, the COLOMBIAN GEOLOGICAL SERVICE informs that:

For the week from January 23 to January 30, 2018, the seismic activity recorded a decrease from the previous week, from 324 to 213 events, dominated by earthquakes related to the movements of fluids from a transient source over time. Most of the time, rock-fracture-type seismicity is located near the Mundo Nuevo crater (southwest of the Cumbal volcanic complex), with depths of up to 8 km on the upper (4700 m) and amplitude local maximum of M0.7 on the Richter scale.

Favorable climatic conditions on the summit made it possible to observe the emissions of 23, 24 and 29 January from the El Verde fumarole field, in the north of the volcanic complex. The emission columns were observed white, of low height and of direction of dispersion dispersed by the action of the wind.

The Colombian Geological Survey continues to monitor the evolution of the volcanic phenomenon and will continue to report in a timely manner if changes are detected.

Source : Ingeominas

 

Turrialba , Poas , Rincon de la Vieja , Costa Rica :

Report on the state of Turrialba, Poás and Rincón de la Vieja volcanoes in the last 24 hours, updated on February 4, 2018 at 11:00.
Turrialba: intermittent emission of ash and fine particles continuously.
Poás: the hyper-acidic lake receives progressively fewer contributions of magmatic fluids.

Turrialba Volcano:
Since yesterday afternoon, there is a continuous emission of fine ash from the west crater, relatively small, associated with seismic signals of continuous volcanic tremors of small amplitude but variable. The column of gas, aerosols and ashes does not rise beyond 300 meters above the summit of the west crater. The winds blew west – northwest. Sulfur odors have been reported in Coronado and Rancho Redondo, but so far no reports of ash fall have been reported. The OVSICORI-A volcanic aerosol monitoring instruments located in Coronado-San Jose have detected a significant increase in the concentration of sulfur dioxide (SO2) and aerosol PM10 gases, particularly in atmospheric air, during the morning of today, the 4th of February.

 

Although SO2 concentrations remained below the maximum allowable limit of 75 ppb, the concentration of P10 fine particles and PM2.5 in air for periods of time less than 24 hours were greater than or equal to values ​​equal to the maximum allowable of 100 ug / m3 and 35 ug / m3. The presence of this amount of PM10 and PM2.5 has the potential to affect the health of people particularly sensitive to environmental changes, young children, the elderly and people with respiratory diseases, cardiovascular and allergies. It is recommended to stay indoors and not exercise outdoors when there are these environmental conditions.
The level of seismic activity generally remains low and is characterized mainly by long-lived volcanic (LP) type earthquakes, and low amplitude volcanic tremors in relation to the movement of fluids (gas, water, or magma) to inside the volcano.

Poas Volcano:
It has not been observed or reported by the public, emissions, ash falls or perceptions of sulfur odors. The winds blow to the southwest.
Seismographs have a very low seismic level; sporadic and low-frequency volcanic earthquakes, products of activity in the hydrothermal system.
The hyper-acidic lake has a stable water level, strong evaporation in the central part and the northern part due to the flow of gas and heat through the underwater fumaroles (Fumarola B and Fumarola D). The milky pale green color of the lake indicates more hydrothermal than magmatic fluids, which corresponds to the gradual cessation of eruptive and fumarolic volcano activity.

The ratio of hydrogen sulphide gas and sulfur dioxide (SO2 and H2S) emitted by Poás shows a moderate increase on February 2 compared to the typical values ​​that have been observed in recent days (H2S / SO2 = 0.40 ). The reasons for these changes in emissions of these gases and lake conditions generally indicate that the Poas system is in a transition regime from a magmatic regime to a hydrothermal regime. This is characterized by the reduction of the flow of oxidizing gases and the heat emitted from the magma to the hydrothermal system. .

Rincón de la Vieja Volcano:
The seismic activity is weak, very weak low frequency volcanic earthquakes associated with fluid movements in the hydrothermal system are recorded very sporadically.
This morning, good weather conditions over the Rincon have observed on the webcam located 5 km north of the volcano, condensation of steam inside the main crater (the lake where there are fumaroles under -marines, and subaerial fumaroles existing on the inner walls of the crater). The vapors emitted by the crater of Rincón are transported by the prevailing winds to the South-West.

Source : Ovsicori

 

Mount Michael , South Sandwich Islands  :

Sunday, 4 February 2018
Thermal anomaly detected on Mount Michael

In a satellite image by Landsat 8 taken on the 31st January 2018, a thermal anomaly is present inside the summit crater of Mount Michael on Saunders Island. It is clearly an indicator that some elevated activity has been taking place inside the crater of Mount Michael.

It is posssible that some low level strombolian activity has been occurring or at least a lava pool is present on the crater floor.

Activity inside the crater of Mount Michael Volcano. SOURCE: Landsat 8/USGS/NASA.

Saunders Island is a volcanic structure consisting of a large central edifice intersected by two seamount chains, as shown by bathymetric mapping (Leat et al., 2013). The young constructional Mount Michael stratovolcano dominates the glacier-covered island, while two submarine plateaus, Harpers Bank and Saunders Bank, extend north. The symmetrical Michael has a 500-m-wide summit crater and a remnant of a somma rim to the SE. Tephra layers visible in ice cliffs surrounding the island are evidence of recent eruptions. Ash clouds were reported from the summit crater in 1819, and an effusive eruption was inferred to have occurred from a N-flank fissure around the end of the 19th century and beginning of the 20th century. A low ice-free lava platform, Blackstone Plain, is located on the north coast, surrounding a group of former sea stacks. A cluster of parasitic cones on the SE flank, the Ashen Hills, appear to have been modified since 1820 (LeMasurier and Thomson, 1990). Vapor emission is frequently reported from the summit crater. Recent AVHRR and MODIS satellite imagery has revealed evidence for lava lake activity in the summit crater.

 

Sources : southsandwichmonitoring.blogspot.fr , GVP

 

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