April 28 , 2016. EN. Santiaguito , Nevado Del Ruiz , White Island , Reventador .
April 28 , 2016.
Santiaguito , Guatemala :
Guatemala April 27, 2016 12:00 (local time)
Lahars threat in areas of Fuego and Santiaguito volcanoes.
The constant activity of the Santiaguito and Fuego volcanoes in recent months, has led to the accumulation of volcanic material in the ravines and surrounding areas.
In recent days, the accumulation of precipitation in these volcanic regions remains constant and there is a possibility that it persists in the coming days, so that the deposited materials can be sucked into the main tributaries, generating the descent of lahars.
These lahars, moderate to strong, can drag blocks up to several meters in diameter and even vegetation. Due to the high activity of the volcanoes, some lahars can come down with a high temperature. This can cause damage to access roads and infrastructure, primarily in the bed of the river Samalá on the bridge Castillo Armas that was assigned during the winters by the occurrence of lahars from areas of Santiaguito volcanic complex .
Volcano Fuego regions may also be affected, mainly in ravines Honda, Las Lajas, El Jute, Trinidad, Ceniza, Taniluyá and Santa Teresa, rivers tributaries: Pantaleon, Achiguate and Guacalate.
Therefore, the INSIVUMEH recommends:
To take precautions on overpasses of vehicles mainly in the area where these channels down.
To the Department OF ROADS:
To take precautions due to continuous rains that can cause damage to road infrastructure mainly on bridges, passages of vehicle or any other infrastructure where the flow of these rivers is headed.
Source : Insivumeh, GVP.
Photo : Photovolcanica.
Nevado Del Ruiz , Colombia :
The level of activity continues at:
Activity level Yellow or (III): changes in the behavior of volcanic activity.
Regarding the monitoring of the activity of the Nevado del Ruiz, the SERVICIO Geologico COLOMBIANO reports:
During the last week the seismic activity of the Nevado del Ruiz volcano was mostly associated with rock fracturing within the volcanic edifice, showing a decrease in both the number of events and the energy released by them . Earthquakes were mainly located in the North distal area, 7.0 km away compared to the Arenas crater at depths between approximately 6.0 and 8.0 km.
And in the northern area of the crater to 4.0 km, with depths between 4.0 and 6.0 km and to a lesser extent in the Arenas crater and in the South of it. The maximum energy of the week corresponds to an event of magnitude 1.2ML (local magnitude), recorded on April 19 at 18:09 (local time), located in the North distal area at a depth of 7.05 km. Seismic activity related to fluid dynamics in volcanic conduits, characterized by the occurrence of earthquakes long period (LP) and very long period (VLP), as well as episodes of continuous volcanic tremor, weak, is also recorded, with an energy level and a pulse mode having different energy levels, some associated with process of emission of gas and ash. These events were in the Arenas crater, near the South-East and North-West.
The volcanic deformation measured from electronic inclinometers, global navigation satellite systems (GNSS) and satellite images to track changes in the tilt, the position and shape of the volcano (respectively), continues to record changes.
The volcano continues to emit into the atmosphere large amounts of water vapor and gases, including sulfur dioxide (SO2), as it was felt by the permanent stations SCANDOAS installed in the Volcano area and by satellite imagery.
In satellite surveillance images provided by the portal Mirova he identified a thermal anomaly in the vicinity of Arenas crater, reported on 20 April, with a value of 6 MW during the week. The persistence of these anomalies confirms the instability of the Nevado del Ruiz volcano and confirmed that the volcanic process continues to evolve.
The column of gas, steam and ash reached a height of 1,700 meters above the summit of the volcano. This height corresponds to the vapor column of April 21. The direction of the dispersion of the column was in line with the prevailing wind in the area, which during the week showed a predominant direction towards the northwest and to a lesser extent to the southwest of the volcano .
Source : SGC.
White Island , New Zealand :
Routine monitoring of White Island (Whakaari) indicates minor volcanic unrest continues. Over the last couple of weeks GNS scientists have observed a fall of 2 m in the water level of the Crater Lake. However they have not noted any changes in other monitored parameters like the amount of volcanic gas being emitted, fumarole temperatures and the presence of volcanic tremor or earthquakes.
During a visit last week by GNS volcanologist Brad Scott he was able to confirm the lake level has dropped 2 m in the last 2 weeks. The lake is now at about the same level it was in 2014. The drop in water level of the Crater Lake has revealed several islands or crater outlines and the lake temperature has increased 2 ºC (56-58 ºC) since February.
There has been a small decrease in the temperature of the hottest fumarole (169 to 161 ºC) since February. The SO2 gas output has ranged between 90 and 480 tonnes per day (1.0 to 5.5 kg per second) of gas during the last 5 weeks. These are typical values for White Island.
The level of volcanic tremor continues to vary, but remains below those observed in 2012 when unrest was stronger and small eruptions occurred.
The Volcanic Alert Level remains at Level 1 (minor volcanic unrest). The changes we are seeing presently are consistent with minor volcanic unrest. Typical volcanic unrest hazards like hot ground and gas remain. A range of activity can occur under these conditions with little or no useful warning.
Volcanic Alert Bulletin WI 2016/02:
11:33am Thursday 28 April 2016; White Island Volcano
Volcanic Alert Level raised to 3
Aviation Colour Code changed to Orange
An eruption occurred at White Island (Whaakari) sometime between 9:30 – 11:00 pm yesterday (Wednesday, 27 April 2016).
As a consequence of this activity the Volcanic Alert Level is now raised to Level 3 (Minor Volcanic Eruption) and the Aviation Colour Code to Orange.
No eruptive activity has been seen since about 11:00 pm yesterday.
The eruption that occurred Wednesday 27 April was accompanied by a moderately elevated seismic activity. The seismic activity is now back to normal.
The eruption appears to have deposited material over north side of the crater floor and up onto north crater wall.
There is not yet a clear view of crater area visible from cameras.
GNS Science volcanologists are monitoring the volcano and further information will be released as soon as it is available.
Source : Geonet ( Bradd Scott , Agnès Mazot )
Reventador , Ecuador :
Wednesday, April 27, 2016
SUMMARY OF THE ACTIVITIES OF THE VOLCANO
Activity remains high on the volcano.
During the night, it was observed explosions accompanied by the expulsion of incandescent blocks up to about 1,000 meters below the crater.
During the morning, the volcano remained clear and it has been observed slight gases and water vapor in South West direction.
ANNEX TECHNICAL AND OBSERVATIONS.
From 11:00 (TL) yesterday until 11:00 (TL) today, 53 explosions, 46 events long period (LP), 6 episodes of harmonic tremor (TRA), 8 episodes of tremor emission and 2 events volcano – tectonic (VT) were recorded.
Observations emissions and ashes:
During the night, at different times cleared at the summit, explosions were observed accompanied by incandescent blocks falling back to about 1000 meters below the crater level.
Today, this morning, the volcano remained clear and it has been observed slight gases and water vapor in South West direction.
Rain and lahars:
There was no rain in the area.
This report on a daily basis will be published at 12:00 (TL). In the case of an increase or a change in the behavior of the volcano will be issued a special report immediately
Source : IGEPN
Photo : Juan Carlos Diaz.