March 20 , 2017. EN. Copahue , Nevados De Chillan , Cayambe , Ubinas .
March 20 , 2017.
Copahue , Chile :
During this period, thirteen (13) seismic events, of which twelve (12) were classified as volcano-tectonic (VT) events associated with rock fracturing processes, were recorded.
For VT seismicity, the local magnitudes (ML) were less than or equal to M1,2. The largest energy event was located in the Northeast (NE), 14 km from the El Agrio crater, with a depth of 4.2 km.
Throughout the period, a constant amplitude constant tremor signal, mainly associated with the exit of gases from the El Agrio crater, with less energy than in previous months was recorded. This signal showed average displacement values (RDC) of 0.4 cm2. The dominant frequencies are concentrated over a bandwidth ranging from 1.2 to 2.1 Hz.
From the data obtained by the three GNSS stations which measure the deformation of the surface of the volcano, variations were observed with a displacement of less than 0.5 cm, considered to be low.
Sulfur dioxide (SO2) emissions recorded by Triplets station , Differential Absorption Spectrometry (DOAS) equipment located 5 km east-northeast (ENE) of the active crater showed a mean value monthly of 695 ± 408 t / day, and a daily maximum of 1702 t / day reported on 11 March. SO2 emissions are at levels considered low for this volcano.
The IP cameras installed near the volcano recorded a constant degassing of the active crater (El Agrio). Most of the time, these plumes were whitish with sporadic emissions of particulate matter. The highest column was recorded on the 4th of this month, with a height of about 350 m.
No emission of sulfur dioxide (SO 2) into the atmosphere in the volcanic field area has been reported, according to data published by IMO, Group Sulfur dioxide (http://so2.gsfc.nasa.gov /) and NESDIS (http://satepsanoine.nesdis.noaa.gov).
No thermal alerts were reported in the area associated with the volcano according to data processed by Mirova (http://www.mirovaweb.it/) and MODVOLC (http://modis.higp.hawaii.edu/).
During the first half of March, there was a marked decrease in the production of seismic events (VT, LP, VLP) compared to the trend reported in the previous months. No incandescence was visualized at night, and during the day, a white column was preferentially observed, indicating predominance of water vapor, with sporadic episodes of particulate matter emissions. Similarly, volcano deformation measurement data, gas geochemistry, interfere with the stability of the system, without significant changes in recordings. In conclusion, the system has a tendency to stabilize its internal dynamics, reflected by the low seismic activity and a decrease in surface activity, however, given the characteristics of the volcano and its recent eruptive history, Not to exclude occasional increases in activity associated with small phreatic explosions and / or weak strombolian activity in the areas surrounding the crater. The level of volcanic alert remains at:
YELLOW LEVEL: changes in the behavior of volcanic activity.
Note: It is recommended as a preventive measure to apply access restrictions in a zone close to the crater with a radius of 1.5 kilometers.
Source : Sernageomin
Photos : RTS , Sernageomin.
Nevados de Chillan , Chile:
– During this period, 1337 seismic events, of which twenty-six (26) were classified as volcano-tectonic (VT) events, processes related to the fracturing of a rigid material with a maximum local magnitude (ML) of M 2.0 were recorded. The highest energy earthquake was located 7.6 km south-south-east (SSE) of the active crater at a depth of 2.8 km. Similarly, 1277 earthquakes associated with fluid dynamics within the volcano, of which 1184 were classified as long-term events (LP), with a recorded maximum recorded displacement value (DRC) of 187.6 cm2 have also been registered. Ninety-three (93) tremor-type seismic events with recorded maximal displacement values of 41.5 cm2 and dominant frequencies between 1 and 3 Hz, as well as thirty-four (34) long-term events , Tornillo (tO) type, resonance related to the transport of magmatic and / or hydrothermal fluids in the volcanic ducts were recorded.
After a period of relative equilibrium, which lasted for a period of one and a half month without explosive activity, on March 7, began a new explosive stage (see details in REAV Biobío Region 14 March 2017. 13 : 00).
The images obtained from cameras installed near the volcanic complex showed explosions around the currently active craters with maximum heights of 1600 m. Since 8 March, it has been observed that some of the explosions generate the expulsion of incandescent material which is deposited on the zones adjacent to the craters currently active, phenomenon preferentially observed during the night.
According to data obtained from four (4) GNSS stations, which measure the deformation of the volcano surface, no significant changes were observed. Lengths of control lines across the active craters showed variations of less than 0.5 cm / month, suggesting that there are no significant changes on the active volcano. The data provided by two (2) electronic inclinometers also suggest that there are no significant inflationary processes associated with this process.
On March 15, an overview of the surface , for evaluate changes associated with this process was conducted. The biggest change observed from the morphological point of view and because of the succession of explosions last week is that two of the craters generated in the previous cycles joined together to form a crater about 100 m in diameter, Which may have occurred in the period between 7 and 15 March 2017. The thermal images taken at the top show low temperatures similar to those obtained in previous overflights which do not exceed 75 ° C
No emission of sulfur dioxide (SO 2) into the atmosphere next to the volcanic field has been reported, according to data published by IMO, Group Sulfur dioxide (http://so2.gsfc.nasa.gov /) and NESDIS (http://satepsanoine.nesdis.noaa.gov).
No thermal alerts were reported in the area associated with the volcano according to the data processed by the infrared observations Mirova (http://www.mirovaweb.it/) and MODVOLC (http://modis.higp.hawaii.edu /).
It is suggested that magmatic body activity apparently increased to more superficial levels, generating a process of greater interaction with the surface hydrothermal system, favoring a series of explosions. Consequently, in the current scenario the appearance of new explosions of similar size or even larger than that recorded is possible. Therefore, the volcanic technical alert remains at:
YELLOW LEVEL: changes in the behavior of volcanic activity – probable time for a rash: weeks / months.
Note: Due to the energy of the process, it is recommended to maintain the area of high volcanic hazard within a radius of 3 km around the currently active craters.
Source : Sernageomin .
Photos : T13.cl
Cayambe , Ecuador :
Summary of Activity, March 11 to 17, 2017
The activity of the Cayambe volcano since March 11th shows a moderate level similar to that recorded in recent weeks. However, it should be noted that on Saturday 11 and Sunday 12, it increased. Earthquakes of higher magnitude were observed than in previous weeks (max. Size M2.9). The events were mainly volcanic-protective (Figure 1). The number of earthquakes was similar to other episodes during 2016.
After this episode, we returned to the same level of activity as the previous days.
Fig.1: Total number of seismic events recorded per day under the Cayambe volcano during 2016 and 2017.
Note that the other monitoring parameters did not show any changes. It is also reported that climbers indicate that the smell of sulfur is low at the top and is not comparable to October and November 2016. On the other hand, a technician from the Institute has reached the top this weekend and observed that the crack of the summit has not changed significantly (Figure 2), while the gap in the bottom seems to be slightly larger.
For these reasons, activity remains moderate, under the same scenarios proposed in the previous year.
The Institute of Geophysics continues its daily monitoring of the volcano and any change in its activity will be the subject of a report.
Source : MP, PM, AA, MS
Escuela Politécnica Nacional
Ubinas , Péru :
Currently, the Ubinas volcano has shown an increase in its seismic and fumarollian characteristics. It is monitored and reported by the OVS-PGI telemetry stations via the network, which sends real-time information to the Cayma headquarters.
Summary of activity between 01 and 15 March 2017.
Hybrid events, associated with rising and / or magma movements, showed a slight increase from that observed in the previous period. It was recorded an average of 11 events per day. In addition, energy this type of earthquakes remains at low levels. However, on March 15th, there was a significant energy peak, with a maximum reduced displacement (DR) of 9 cm 2 and 40 cm 2, which is a sign of magmatic matter going back to the surface.
VT type events, related to rock breakage, show a slight increase compared to that observed during the previous period. On average, 38 VT events were recorded per day with a maximum of DR. equal to 5 cm 2.
Tremor seismicity shows a marked decline, with the average recording of only 1.5 hours of daily tremor. This indicates that the disturbance of the hydrothermal system has decreased.
During this period, no explosive events were recorded.
Thermal anomalies and SO2: The Mirova system (mirovaweb.it) did not detect any thermal anomalies during this period. In addition, the satellite system « EOS Aura » GSDM-NASA (http://so2.gsfc.nasa.gov/) did not detect any significant anomalies during this fortnight.
During this period of surveillance (01 to 15 March), the clouds clearly prevented seeing the volcano. However, it was possible to distinguish sporadic expulsions of bluish gas (magmatic gases) up to 300 meters above the crater. No expulsion of ash was observed.
The slight increase in hybrid and VT-type earthquakes indicates a small increase of magma in areas below the surface of the volcano
Source : IGP
Photo : Ingemmet