February 16 , 2016. EN. Nevado Del Ruiz , Momotombo / Telica , Cotopaxi .
February 16 , 2016.
Nevado Del Ruiz , Colombie :
Weekly activity report of the volcano Nevado del Ruiz, from 2 to 8 February 2016
The level of activity continue at level :
Activity level Amarillo or (III): changes in the behavior of volcanic activity.
Regarding the monitoring of the activity of the Nevado del Ruiz, the Colombian Geological Service reports that:
During the last week, the volcanic system continued to show unstable behavior. The recorded seismic activity is mainly associated with the fracturing of the rock in the volcanic structure. This type of seismicity was located mainly in the North and Northeast areas, and to a lesser extent, scattered in the North distals sectors, Southwest and North West of Arenas crater. Earthquakes depths during the week were between 0.7 and 8.1 km. Two increases in activity were highlighted during the 03 and 6 February.
The first increase was located in the Northeast area, at depths between 3.2 km and 6.4 km, with a maximum magnitude of 2.7 ML (local magnitude) at a depth of 5.3 km, corresponding to the earthquake on 3 February at 5:01 p.m. (local time). The second increase was located in the northern sector, at depths of between 4.3 km and 7.1 km, with a maximum magnitude of 3.6 ml (local magnitude) at a depth of 4.97 km, recorded at 20:39 (local time) on February 6. This event corresponds to earthquake of greater magnitude of the week and was reported as felt by the inhabitants of the area of influence of the volcanic edifice, as well as in the municipalities of Manizales and Villamaría (Caldas).
Seismic activity related to fluid dynamics inside volcanic conduits, was characterized by the occurrence of earthquakes long period (LP) and an episode of continuous tremor, recorded with a low energy level. These two signals are mainly located near the Arenas crater and in the South – Southeast sector of the volcano. These processes were accompanied by temperature anomalies, low to moderate, followed by satellite images provided by the system Mírová, from Italian universities of Turin and Florence. These thermal anomalies, on 03 and 07 February have been identified near the Arenas crater, confirming the instability of the volcanic structure.
The volcanic deformation measured from electronic inclinometers, global navigation satellite systems (GNSS) and satellite images, which record changes in the tilt, the position and shape of the volcano (respectively) during the last period evaluated recorded no change.
The volcano continues to emit into the atmosphere of significant amounts of water vapor and gases, including sulfur dioxide (SO2), as has been estimated by the permanent stations SCAN DOAS installed in the volcano area and satellite imagery.
The column of gas, steam and ash reached a height of 1500 meters above the summit of the volcano, on February 6. The direction of the dispersion of the column is in line with the prevailing wind in the area, which during the week showed a predominant direction towards the northwest over the volcano.
It is considered that the volcanic system continues to evolve. No new events that may indicate an acceleration of the process, involving greater instability of it requires the changes in activity level. While the instability of the volcano lasted for over five years, it is essential not to get used to a seemingly monotonous behavior of the volcano and monitoring official information that may be published by the Colombian Geological Service.
Source : SGC.
Momotombo / Telica , Nicaragua :
Explosion at Momotombo volcano, Nicaragua
15 FEBRUARY 2016. An explosion occurred at 1:04 pm in the Momotombo volcano on Monday 15 February, as reported by the Nicaraguan Institute of Territorial Studies (INETER).
The explosion lasted until 1:12 pm. Seen in real-time on webcams showing that Momotombo volcano expelled gases and ash.
On Sunday, the authorities of the National System for Prevention, Mitigation and Attention to Disasters (SINAPRED) expressed concern about the seismic activity in the Cerro Negro.
On Saturday February 13 , the Telica volcano experienced an explosion with expulsion of gases and ash, officials said.
Rosario Murillo, coordinator of communication and citizenship, during his daily official media report, said that the Momotombo registered high emission also added that US experts have arrived in the country to study the volcanoes that are currently recording activity.
15 FEBRUARY 2016. Authorities in Nicaragua activated emergency plans after explosions occurred at both the Momotombo and Telica volcanoes on Saturday. Meanwhile, the Masaya volcano has also witnessed an increase in seismic activity in recent days.
According to the Nicaraguan Institute of Territorial Studies (INETER), the Telica volcano, located in the Leon department, erupted at 8:28 a.m. Saturday morning, launching a column of ash and gas some 1,000 meters (3,280 feet) into the air. At least 20 smaller eruptions were recorded at the volcano in the subsequent hours. Ashfall was reported in some nearby communities.
About two hours after the first explosion at Telica, the Momotombo volcano – which had been essentially dormant for 100 years before exploding to life in December – launched a column of ash and gas more than 1,600 feet (500 meters) into the air.
There were no injuries reported in either event, though Civil Defense and municipal authorities said they were activating emergency plans in order to provide a rapid response should communities become at risk. Civil Defense authorities also visited communities near the Momotombo to coordinate evacuation routes should a major incident occur.
Sources : La Prensa. Costa Rica star.
Photo : Ineter.
Cotopaxi , Equateur :
On January 26, 2016, with the logistical support of an aircraft of MICS, a survey was held from Tababela airport to the Cotopaxi volcano with a Twin Otter aircraft FAE (452), commanded by Captain Urquizo, following the path shown in Figure 1
The conditions under which the flight took place were very favorable, because the volcano was completely uncovered and on the other hand, the high cloud cover remained on the volcano most of the time, so there was no solar radiation effect on the volcano for thermal imaging. During the approach the volcano, it was observed that the crater emitted a small column of water vapor, pulsating, which mostly remained within the crater, sometimes not exceeding more than 500 meters over well top and finally moving to the west (Fig. 2).
Figure 2: View of the upper south flank, Southeast and East, noted the low water vapor emission which moves westward (Photo: P. Ramón IG / EPN).
Since the volcano was quite clear, it was confirmed once again what we observed in the past, the presence of water and humidity from contact areas of the tongues of all the glaciers in the area, these forming thin streams of water that descend downstream by the ravines of the volcano flanks, which can lead to the generation of small lahars (fig. 2). This time, it was obvious that, due to the increase in melting ice, we are witnessing the formation of cracks fractures all over the ice cap, but which are particularly sensitive to any glaciers front areas ( FIG 3).
Figure 3: a view of the glaciers of the South left flank, completely cracked (Photo: P. Ramón IG / EPN).
On the upper east side, it was observed that the glacier area has experienced rapid melting, which led the fall of materials deposited on the top to the lower glacier, which therefore now has a dark color. It should be noted that this material was not present before, during observations of the flight of December 15, the ash fall has not occurred in this region of the volcano (Fig. 4).
Figure 4: East side of Glacier; melting glaciers from the top edge of the crater causes detachment of rock material on the lower glacier, so it appears dark. (Photo: P. Ramón IG / EPN).
Good weather helped to measure the temperature of most thermal anomalies identified on the volcano. It was not noted major changes inside the crater in relation to that observed in November. Due to water vapor emissions during the observation (TMA), temperature measurements in the crater, 51.9 ° C that have been observed, are lower than the actual value.
Figure 5: Sup: Thermal image showing a TMA of 51.9 ° C at the bottom of the inner crater. Inf :. corresponding visible image, the presence of steam emission decreases the real value of the temperature at the crater. (Photo / Photo: P. Ramón IG / EPN).
As regards fields fumarole it was determined that the TMA values are mostly similar or lower than those measured on 15 January, except for slightly higher values measured on the south side, inner crater Anillo Arena Internal , Yanasacha, Glacier Circular , low Fumarola from North Summit. Contrary to what was observed at the end of September 2015, the fumaroles activity in most areas no longer generates precipitation of mineral deposition and possibly sulfur (greenish).
During this overview again, it was possible to identify thermal anomalies in areas were deposited materials of the upper parts of the outer crater reworked, particularly on the east and southeast flanks. These areas have reached a TMA value of 14.7 ° C. It should be noted that the entire upper half of the glacier is covered by these products, helping the melting process on the glacier, decreasing albedo ..