October 26 , 2017.
Nevado del Ruiz , Colombia :
Subject: Bulletin of activity of the Nevado del Ruiz volcano.
The level of activity continues at the level: Activity level yellow or (III): evolution of the behavior of the volcanic activity.
With regard to monitoring the activity of the Nevado del Ruiz volcano, the COLOMBIAN GEOLOGICAL SERVICE reports that:
During the last week, the various monitoring parameters show that the Nevado del Ruiz volcano continues to exhibit unstable behavior.
The seismicity caused by the fracturing of the rocks that make up the volcano showed a decrease in both the number of earthquakes and the released seismic energy, compared to the previous week. The earthquakes were mainly located in the northern distal sectors, 6.7 km from the Arenas crater and, to a lesser extent, in the north-east, south-east, south, southwest and around the crater. The depths of the earthquakes ranged between 0.6 and 8.4 km. The maximum magnitude recorded during the week was 1.3 ML (Local Magnitude) for the October 18 earthquake at 4:13 am (local time), located 2.2 km southeast of Arenas Crater, at a depth of 3.5 km.
The seismic activity associated with fluid dynamics within the ducts of the volcanic structure showed a slight increase in the number of recorded earthquakes, and maintained similar levels in released seismic energy, compared to the previous week . This type of activity was mainly characterized by the occurrence of fluid earthquakes, long-period and long-term events, as well as tremor impulses. These earthquakes were mainly located near the crater Arenas.
Volcanic deformation measured from electronic inclinometers, Global Navigation Satellite System (GNSS) stations and radar images shows stability behavior. No significant deformation process of the volcanic structure has been recorded.
The volcano continues to emit water vapor and gases, including sulfur dioxide (SO2), as evidenced by the values obtained by the SCANDOAS stations installed in the volcano region and satellite image analysis. In monitoring the information provided by the MIROVA and NASA FIRMS portals, warnings associated with thermal anomalies were recorded on 17 and 20 October with an energy of 7 MW in the vicinity of the Arenas crater.
The column of gas and steam reached a maximum height of 1700 m measured on the summit of the volcano on 23 October. The direction of the dispersion of the column was governed by the direction of the wind in the zone, which during the week predominated to the northwest relative to the crater Arenas.
The Nevado del Ruiz volcano continues at the level of activity yellow .
Source : Ingeominas
Shinmoedake , Kyushu , Japan :
Elevation 1700 m
JMA reported that the eruption at Shinmoe-dake (Shinmoe peak), a stratovolcano of the Kirishimayama volcano group, began on 11 October and lasted almost continuously until the morning of 17 October. The eruption plume usually rose several hundred meters about the crater rim, though on 14 October the plume rose as high as 2.3 km. Sulfur dioxide flux exceeding 10,000 tons/day was also recorded. Cloudy weather conditions prevented webcam views during 19-20 October. Plumes rose 200-600 m on 21, 23, and 24 October. During an overflight on 24 October scientists observed a white plume rising from the active vent on the E side of the crater, and puddles in multiple low areas of the crater. The Alert Level remained at 3 (on a scale of 1-5).
Kirishimayama is a large group of more than 20 Quaternary volcanoes located north of Kagoshima Bay. The late-Pleistocene to Holocene dominantly andesitic group consists of stratovolcanoes, pyroclastic cones, maars, and underlying shield volcanoes located over an area of 20 x 30 km. The larger stratovolcanoes are scattered throughout the field, with the centrally located, 1700-m-high Karakunidake being the highest. Onamiike and Miike, the two largest maars, are located SW of Karakunidake and at its far eastern end, respectively. Holocene eruptions have been concentrated along an E-W line of vents from Miike to Ohachi, and at Shinmoedake to the NE. Frequent small-to-moderate explosive eruptions have been recorded since the 8th century.
Source: Agence météorologique japonaise (JMA) , GVP.
Photo : S Nakano
Fuego , Guatemala :
Type of activity: Vulcanian
Morphology: Composite Stratovolcan
Location: 14 ° 28’54˝Latitude N; 90 ° 52’54˝Longitude W.
Weather conditions: Partly cloudy.
Winds: from the NNW at 5 km / h
Precipitation: 54.8 mm.
The Fuego volcano maintains moderate to strong explosions, expelling gray ash columns at 4800 m. (15,748 feet), moving west and southwest over a distance of 12 kilometers. The explosions generate shock waves and moderate rumblings as well as avalanches of incandescent blocks on the flanks of the volcano. Ash falls are reported in the villages of Sangre de Cristo, El Porvenir, Panimache, Morelia and Hagia Sophia. Due to rainfall, there is still the probability that lahars will be generated in the ravines around the volcanic complex.
Source : Insivumeh
Photo : Getty
Turrialba , Poas , Rincon de la Vieja , Costa Rica :
Daily Activity Report for Turrialba, Poás and Rincon de la Vieja volcanoes:
October 24, 2017, updated at 11:00 pm
Turrialba Volcano: activity over the last 24 hours:
The Turrialba volcano continues with permanent degassing. No ash emission was detected. The plume is less than 500 m above the volcano.
The seismic activity during the last 24 hours has been characterized by signs of discontinuous volcanic tremors of low amplitude and relatively short but variable duration.
At the time of this report, the winds at the top of the volcano are directed mainly to the northwest.
Poas Volcano: activity over the last 24 hours:
The Poas continues with a permanent degassing. The plume is less than 500 m above the bottom of the crater. No ash emission was detected.
The level of seismic activity is low. In general, most of the seismic signals recorded on the Poas are essentially generated by background noise produced by external factors.
At the time of this report, the winds at the summit of the volcano are variable, but oriented mainly towards the East.
Rincón de la Vieja Volcano: activity over the last 24 hours:
During the last 24 hours, no eruption has been detected. The seismic activity continues with a regular spasmodic tremor.
OVSICORI-UNA remains vigilant on seismic and volcanic activity.
Source : Ovsicori
Piton de la Fournaise , La Réunion :
Activity Bulletin from Wednesday, October 25, 2017 to 21:00 (local time).
Since mid-October, a change is observed on the recordings of the volcanological observatory with:
– a resumption of inflation (swelling) of the volcano,
– low concentrations of SO2 (coupled with CO2) and H2S (coupled with H2O vapor) in the summit emissions of Piton de la Fournaise,
– a slight seismicity under the summit craters.
All these parameters will be followed and confirmed in the coming days.
Source : OVPF
Photo : J. Guichard.