16/04/2015. Tungurahua, Nevado Del Ruiz , Ksudach .
Tungurahua, Equateur :
Yesterday at 16:08 TL was recorded an explosion that caused ash column that reaches 3000 m above the crater.
This signal was followed by an episode of tremor, which was accompanied by an emission with moderate ash that reached the 2000 m above the crater, dissipating to the west. It continued until the publication of this report (5:20 p.m.).
This explosion has not generated pyroclastic flows or lava flows, and so far no reports of ash fall, but this possibility is not ruled out.
With this type of volcanic behavior, it is possible that in the coming hoursan increase of the activity should be come; Therefore it is recommended to keep abreast of any changes.
Source : IGEPN
Photo : José Luis Espinosa Naranjo
Nevado Del Ruiz, Colombie :
Activity Level: Amarillo or (III): changes in the behavior of the volcanic activity.
Regarding the monitoring of the activity of the Nevado del Ruiz volcano, SERVICIO Geologico COLOMBIANO through the OBSERVATORIO VULCANOLÓGICO Y SISMOLÓGICO OF MANIZALES, informs that:
During the last week, the Nevado del Ruiz volcano continued to record seismic activity, mainly volcano-tectonic type associated with rock fracturing in the volcanic structure. Earthquakes are located mainly in the north, northeast and south of the crater at depths between 0.5 and 7.5 km. There has been an increase in type of volcano-tectonic earthquakes, between 12 and 13 April; earthquakes were located north of Arenas crater at depths ranging between 3.0 and 7.5 km.
Nevado del Ruiz – sismo du 14.04.2015 – doc. SGS / Observatorio Manizales
The maximum magnitude recorded during the week was 1.9 ML (local magnitude), corresponding to an earthquake located in the northeast of the Arenas crater, which took place April 12 at 13:30 (local time) at a depth of 3.73 km.
Yesterday at 7:39 p.m., it was recorded a volcanic tremor of pulse, followed by an episode of continuous tremor (see chart). This signal was associated with issuance of ash, which were scattered around the towns of Chinchina, Manizales and Villamaria.
Nevado del Ruiz – panache de gaz et cendres du 15.04.2015 – photo SGS / Observatorio Manizales
Regarding fluid dynamics within the volcanic conduit, a low-energy seismic activity was recorded, which was mainly located in the south of Arenas crater. Some episodes of volcanic tremors of low energy associated with the movement of fluids and gases and ash emissions were presented. The continuous volcanic deformation show some changes.
In the atmosphere, the volcano continues to emit significant amounts of water vapor and gases, including sulfur dioxide (SO2). The gas and steam column reached a height of 1800 meters above the top of the volcano, and most of the time was observed white. But sometimes showed gray tones due to the presence of ash. The direction of the dispersion of the column was in line with the wind regime, which remained mainly to the northwest and southwest of the volcanic edifice.
Monitoring of the volcano is a task for everyone, if you see ash falls or changes in the rivers coming from the volcano, if it please report it to the observatory.
Source : SGC
Ksudach, Kamchatka :
After EXERCISE VOLKAM15, Aviation Color code for Ksudach Volcano is returning to Green because the activity of the volcano is weak at now. Satellite data show the volcano is quiet.
Weak gas-steam activity of the volcano continues.
Ongoing activity could affect low-flying aircraft.
Ksudach is unique among Kamchatka volcanoes in its morphology and geologic history. It is a large, low-angle stratovolcano, constructed of alternating basaltic-andesitic lavas and dacitic pyroclastics, and is truncated by an intricate complex of five calderas. An array of post-caldera structures is truncated by later calderas, the last three of which formed during the Holocene, about 7900 and 5000 BCE and about 240 CE. The latter eruption was the second largest in Kamchatka during the Holocene, and produced about 20 cu km of rhyodacitic airfall tephra and 3-4 cu km of pyroclastic flows. The eastern part of the caldera complex contains two lakes, the northern of which forms an embayment in Stubel Crater, a low-angle cone that began forming about 1600 years ago in the youngest caldera. The only historical eruption, in 1907, originated from Stubel Crater and was one of Kamchatka’s largest in historical time.
Source : Kvert , GVP
Photo : I. Romanova, IVS FEB RAS