26/05/2015. Wolf, Popocatepetl , Piton de la Fournaise.
Wolf , Isabella, Iles Galapagos , Equateur :
An eruption started on the Wolf Volcano, located on the island of Isabella, in the Galapagos archipelago.
Around 0:50 yesterday morning (23:50 hours in the Galapagos), seismic stations installed by the Geophysical Institute started recording multiple event signals that occurred in the vicinity of Wolf volcano especially at the nearest station, which about 20 km south-west of the volcano.
The most important seismic signal is received at 1:58 this morning (Fig. 1) corresponding to an explosion, in which began a new eruptive activity of the volcano. The Wolf volcano is located in the northern part of Isabela Island. It is an active volcano and the last eruption took place in August 1982.
To 2:57 (local time Galapagos), the Warning Center Volcanic Ash (VAAC), on the satellite base of information confirms the presence of an eruption column of Wolf, which rises to 35,000 feet and runs to the southwest; then at 4:34 it is reported a column to the east-northeast at an altitude of 50,000 feet and another moving southward at a height of 45,000 feet. At 4:28 (Eastern Time Galapagos) Institute of Geophysics and Planetology (HIGP) of Hawaii reports that its infrared satellite sensors indicate the presence of intense hot spots, located on the southeast flank of the volcano Wolf, confirming the appearance of volcanic activity. From the early hours of this morning, we were in contact with the Galapagos Park staff who compiled and shared pictures of this activity. It is confirmed that the origin of the activity is a crack on the south-southeast upper flank of the volcano, and from where have seen several lava flows down the volcano’s flanks and moving toward the sea.
Wolf, the highest volcano of the Galápagos Islands, straddles the equator at the north end of the archipelago’s largest island, Isabela. The 1710-m-high edifice has steeper slopes than most other Isabela volcanoes, reaching angles up to 35 degrees. A 6 x 7 km caldera, at 700 m one of the deepest of the Galápagos Islands, is located at the summit. A prominent bench on the west side of the caldera rises 450 above the caldera floor, much of which is covered by a lava flow erupted in 1982. Radial fissures concentrated along diffuse rift zones extend down the north, NW, and SE flanks, and submarine vents lie beyond the north and NW fissures. Similar unvegetated flows originating from a circumferential chain of spatter and scoria cones on the eastern caldera rim drape the forested flanks to the sea. The proportion of aa lava flows at Volcán Wolf exceeds that of other Galápagos volcanoes. An eruption in in 1797 was the first documented historical eruption in the Galápagos Islands.
Given how far have evolved the eruption columns, it might be fine ash fall on people of Pto. Villamil. The outpouring of lava flows on the flanks of the volcano, will certainly have effects on the fauna and flora of the area and on the marine environment, once the flows reach the sea.
This morning, the eruptive process is down and apparently, the impact on wildlife is minimal
The Geophysical Institute will continue to inform the community on the development of this new eruptive event.
Source : IGP, GVP.
Photo : Martin Díaz Zúñiga, Parc National Galapagos.
Popocatepetl, Mexique :
May 25 8:15 p.m. pm (1:15 GMT May 26)
At 5:02 p.m. pm, the seismic monitoring system of Popocatepetl volcano recorded an episode of explosions and tremor, accompanied by water vapor emissions, gas and small amounts of ash towards the south-south . This episode ended at 19:35 pm, no report so far on ash fall has been issued.
May 25, 11:15 h (May 25, 16:15 GMT)
In the last 24 hours the seismic monitoring system of Popocatepetl volcano registered 90 low-intensity exhalations, the most important event was recorded today at 00:05. During the previous 24 h of activity the system registered multiple episodes of low amplitude tremors that accumulated to a total of 45 minutes.
In addition, last night we observed incandescence above the crater .
At the time of this report we have partial visibility of the volcano due to overcast conditions. However early this morning clear conditions allowed us to observe emissions of steam and gas from the crater travelling in a south easterly direction .
At the time of this report, it has only partial visibility of the volcano due to the weather, but this morning, the volcano was observed with an emission of steam and gas in the direction of the southeast. On May 9, the Canary monitoring station of Popocatepetl volcano was vandalized. CENAPRED staff later went to the station to restore operation. It should be noted that the Canary station is an important part of Popocatepetl volcano monitoring system. Therefore, you are requested to protect the monitoring stations, which help to keep the public informed about the activity of the volcano.
CENAPRED emphasizes that people SHOULD NOT go near the volcano, especially near the crater.
Source : Cenapred.
Photo : Atlixco el mejor clima del mundo
Piton de la Fournaise, La Réunion :
Activity Bulletin Sunday May 24 23:00 posted 25
The eruption that began on May 17 continues.
The significant fluctuations observed and described the last two days continue.
Figure 1: Evolution of the intensity of the tremor since the beginning of the eruption.
Note that no earthquake has been detected for more than 24 hours.
The emission of SO2 is generally declining. It is however also become fluctuating in time since May 21, 2015.
Rate of the lava flow
(©OVPF/IPGP/Diego Coppola Turin)
Figure 2: Evolution of the lava flow from the beginning of the eruption.
Diego Coppola of the University of Turin has updated its monitoring chart lava flow since May 17 (Figure 2). It shows a certain constancy in the flow rate with the slight fluctuation in 23/05. Coppola explains that the constant flow seems to be a fairly low level, with minor variations.
CAUTION: Modis satellite debit measures are (i) point and (ii) averages rate of effusion. This explains why the peaks are “smoothed”.
Concerning the activity (see above photo), the height of lava fountains appeared similar to those of last Wednesday, the cone has grown and closes more, and most of the lava flows in a tunnel.
The high fluctuations in the phases are associated with increases in the height of fountains (testimonies and Figure 3) and temporary outpourings of lava
Recognition and fieldwork were conducted so far:
Samplings performed on older products up and cracks on an active flow arm very close to the vent (wet samples)
GPS points of the entire crack on which the vent is formed
Gas measurements in the plume
A recognition by the SAG (Section of the Air Force) in the afternoon we learn that:
the flow rate seems to be reduced (probably due to tunnel flow),
fountains seem lower (probably because the cone is above)
the flow front was not observed because of the cloud cover. However, the vertical level of the curve 900, the edge is not visible. For the record last observed localized to approximately 1000m altitude.
Observations Sunday 24 May:
A team from the Volcano Observatory visited the eruption site to conduct surveys:
GPS survey of the crack on which the remaining active vent formed
Gas measurements in the plume
A flow arm is active in the immediate vicinity of the event and could be sampled.
In holding the height of the cone, we could not sample projections (most falling into the cone or on the upper part of the latter).
Source : OVPF
Photos : OVPF , Julien Azam / JIR