October 05 , 2017. EN. Ticsani , Nevado Del Ruiz , Karymsky , Sangay.
October 05 , 2017.
Ticsani , Peru :
Sismo – Volcanic monitoring:
The Ticsani volcano is at the level of activity green . The dominant seismicity of this period was related to the occurrence of earthquakes associated with rock fracturing (VT). However, the average frequency of these events decreased slightly.
VTP events (Volcano-Tectonique Proximal) decreased from 14 to 11 VTP per day. The seismic energy levels of VTP events are low.
VTD-type earthquakes decreased from 27 to 9 VTD per day.
The occurrence of hybrid events on the Ticsani is sporadic. These events are associated with magma movements in a magmatic chamber. During this period, only 2 low energy events were observed.
Location of events:
The calculation of the hypocentric parameters in relation to the spatial distribution of the seismicity shows a small cluster of earthquakes near the Ticsani volcano, extending towards the east. Dispersed earthquakes were also observed towards the south-east of the Ticsani. The seismicity analysis showed earthquakes with magnitudes up to 3.3 ML (local magnitude) and a depth distribution that reached 18 km from the surface.
SO2 Anomalies: The GSDM-NASA (EOS Aura) satellite system (http://so2.gsfc.nasa.gov/) recorded low SO2 gas density values during this period.
Thermal anomalies: The MIROVA system (www.mirovaweb.it) has not detected thermal anomalies on the Ticsani volcano (VPR = 0 Megawatts).
Seismic activity in the Ticsani region remains low. The predominant seismic events in this region are related to rock fracturing processes.
During this period, VTP (Volcano-Tectonic Proximal) earthquakes had an average occurrence rate of 11 VTP per day. Seismicity of VT Distal type, which decreased during this fortnight, recorded a rate of 9 VTD per day. Concerning seismicity of the hybrid type, only 2 events of low energy were recorded.
In the spatial distribution of the seismicity, a group near the Ticsani volcano is observed with a depth distribution reaching 18 km below the surface.
Any changes will be reported in a timely manner.
Source : IGP
Nevado del Ruiz , Colombia :
Subject: Activity report of the volcano Nevado del Ruiz.
The level of activity continues at: Activity level yellow or (III): evolution of the behavior of the volcanic activity.
Regarding the monitoring of the activity of the volcano Nevado del Ruiz, 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 due to fracturing of the rocks that form the volcano decreased in both the number and the energy released, compared to the previous week. The earthquakes were mostly in the distal northern sector, about 6.8 km from the Arenas crater and, to a lesser extent, in the Northeast, South-West and near the crater. The depths of earthquakes ranged from 1.0 to 7.9 km. The maximum magnitude recorded during the week was 2.3 ML (local magnitude), corresponding to two earthquakes, recorded on September 28 at 15:59 (local time) and on September 30 at 9:10 pm (local time) located in the distal northern sector at 7.0 km from the crater at a depth of 5.5 km and 4.96 km respectively.
The seismic activity associated with fluid dynamics within the volcanic structure ducts showed a slight increase in both the number of recorded earthquakes and the seismic energy released compared to the previous week. This type of activity was mainly characterized by the appearance of multiple seismic fluids, of the long period type and very long period, as well as tremor pulses.
Volcanic deformation, measured from electronic inclinometers, satellite navigation systems (GNSS) and satellite imagery, to determine changes in inclination, position and shape of the volcano, continues to record some changes.
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 area and the analysis of the satellite images. In the follow-up of the information provided by the NASA FIRMS and MIROVA portals, an alert associated with a thermal anomaly was recorded on 27 September at 10:20 (local time) with an energy of 10 MW near the Arenas crater.
The gas and steam column reached a maximum height of 1650 m measured at the top of the volcano on 28 September. The direction of the dispersion of the column was governed by the direction of the wind in the zone which predominated towards the northwest in relation to the Arenas crater during the week.
The Nevado del Ruiz volcano continues at the level of yellow activity.
Source : SGC
Photo : Edgar , Semana.
Karymsky , Kamchatka :
VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA).
Issued: October 05 , 2017
Volcano:Karymsky (CAVW #300130)
Current Aviation Color Code:ORANGE
Previous Aviation Color Code:orange
Volcano Location:N 54 deg 2 min E 159 deg 26 min
Summit Elevation:4874.08 ft (1486 m)
Volcanic Activity Summary:
According to satellite data, a moderate ash explosion sent ash up to 5 km a.s.l., ash plume drifted about 21 km to the east-north-east from the volcano.
A moderate activity of the volcano continues. Ash explosions up to 16,400-19,700 ft (5-6 km) a.s.l. could occur at any time. Ongoing activity could affect low-flying aircraft.
Volcanic cloud height:
13120-16400 ft (4000-5000 m) AMSL Time and method of ash plume/cloud height determination: 20171003/2123Z – NOAA 18 (4m5)
Other volcanic cloud information:
Distance of ash plume/cloud of the volcano: 13 mi (21 km)
Direction of drift of ash plume/cloud of the volcano: ENE / azimuth 77 deg
Time and method of ash plume/cloud determination: 20171003/2123Z – NOAA 18 (4m5)
Duration of explosion: ~ 30 minutes
Source : Kvert
Photo : A. Ozerov, IVS FEB RAS
Sangay , Ecuador :
The eruption continues, two vents are observed.
The Sangay volcano has erupted since July 20, 2017. Its activity has not changed much in the last two months, characterized by explosions in the central vents and emissions of lava from the dome Ñuñurco, on the east flank . On the satellite images of August and September (Figure 1), the two active vents were clearly observed. During the last week, there were about 65 explosions and 25 long-duration (LP) events per day, with few harmonic tremors, with no major changes from previous months. There was also low-energy ash emissions (up to 1 km), causing ash falls to the west and northwest of the volcano (Culebrillas and Licto). This low intensity activity is typical of the Sangay volcano and does not pose a threat outside the volcanic cone. Based on the direction and wind speed, ash emissions could cause small ash falls to the west of the volcano and possibly cross some of the country’s air routes.
Figure 1. Satellite image of the Sangay volcano (source: Landsat 8, 20/09/2017).
Over the past few weeks, visual observation conditions have been poor with days completely cloudy and few days with visibility of the area (Figure 2). Surface activity was characterized by low-energy gas and ash emissions at the crater up to 800 m above sea level. The presence of hot matter is confirmed, probably due to new lava flows on the East-South-East flank (Figure 2).
Figure 2: Trace of hot material in the upper part of the volcanic cone, possibly due to a lava flow on the ESE flank of the volcano (source: ECU911, 01/10/2017).
According to the Washington VAAC, 9 clouds of ash have been observed since the last special report (03/08/2017) with heights between 0.5 and 3 km, between Southwest and Northwest and typical speeds of ~ 10 m / s
Infrared (thermal) sensors on various orbiting satellites detected the presence of heat on the Sangay volcano over the last two days
Figure 3: Thermal anomalies detected by FIRMS on Sangay volcano, 2 October 2017 (source: HGIP, Hawaii, FIRMS).
The FIRMS system detected 7 thermal anomalies on 2 August, which are clearly aligned on the ESE flank (proof of lava flow). The Sentinel-2 and Landsat-8 satellites clearly show two hot spots on the volcano, the first associated with the central vent from which the ash emission columns emerge, the second associated with the Ñuñurco vent emitting a flow of washed eastward (Figure 4).
Figure 4: Satellite images between August 3 and September 20, 2017 (source: Landsat 8 and Sentinel 2).
From 17 August, the reception of the recordings of the multi-component station SAGA, located on the south-west flank of the volcano, began for hours. The acquisition of these partial data continues. In the last week, an average of 65 explosions and 25 long-term earthquakes (LP) per day was extrapolated. There were also some signs of harmonic tremor. Figure 5 shows the acoustic and seismic recordings of two explosions. In general, the current seismicity is similar to that of earlier eruptions of Sangay (eg, March-July 2016).
Figure 5: Acoustic recording (BDF) and seismic (HHZ, vertical component) of double explosion on the Sangay volcano on 27 September 2017 (source: IG-EPN).
No significant changes were observed in the monitoring parameters of the Sangay volcano during the last 2 months of eruption, similar to the activity observed in previous years.
Based on the direction and speed of the wind, ash emissions could cause small ash falls to the west and northwest of the volcano and possibly cross some of the country’s air routes.
Thermal alerts indicate the descent of lava flows on the east-south-east flank of the volcano, which can collapse and produce small pyroclastic flows. The elimination of unbonded materials in the upper parts, for example by heavy rains, could produce small lahars in the Volcán and Sangay rivers. This phenomenon does not represent a threat outside the volcanic cone.
The IGEPN is very conscious of any modification of the conditions presented by the volcano.
Source : IGEPN