April 29 , 2019.

Mexico , Colima :

The volcano Fuego de Colima recorded a change in its activity.

Academics and state civil protection systems have reported a significant increase in the seismicity of Fuego de Colima, located within the boundaries of the states of Jalisco and Colima, so that the volcanic signal light has turned yellow.
After the peer review, it was agreed to increase the exclusion zone of the two states to 8 kilometers. « On the basis of the above, two probable scenarios are proposed in the short term: the first, a moderate explosion, accompanied by a growth of the dome, the second, the growth of a dome in the crater and a lava flow later on the volcano « .
Citizens are advised to respect the exclusion zone and to remember that they can carry out their normal activities, but they must be kept informed of the level of alert levels and the evacuation procedure.

Weekly technical bulletin of the Colima Volcano activity
Date: April 26, 2019 Bulletin No. 118

Seismic activity:
Last week, 61 high frequency (HF) events, 25 long period (LP) events, 2 landslides and 43.9 min of low amplitude tremors were automatically recorded.

Visual observations:
During the reporting period, it was not possible to observe steam and gas emissions mainly in the eastern part of the crater. The thermal camera recorded no anomalies related to possible changes in the external volcanic activity.

Geochemistry:
SO2 flow measurements were made on April 24, the value was below the detection level of the instrument.

Remote perception:
No thermal anomalies detected by the MIROVA satellite system were observed during the last week.

Diagnostic:
Last week, the volcano increased its internal seismic activity, without this resulting in an increase in surface volcanic activity; this had already been observed in previous years before the explosion and / or the growth of a new dome. The staff in charge of monitoring the volcano is attentive to possible changes and changes in activity.

Possible scenarios for the coming days and weeks:
1. Moderate explosion and / or series of explosions.
2. There is new growth of lava dome at the top with collapses of incandescent material and lava flows.

Source : infobae.com , RESCO-CUEV-Faculté des sciences Université de Colima.

Photo : Raul Arambula / RESCO-CUEV .

Costa Rica : Poas / Rincon de la Vieja / Turrialba :

Daily report of the state of volcanoes. Date: 2019-04-27, Updated at: 10:10:00 AM.

Poas Volcano:
No eruption is reported.
The seismic activity is similar to that of yesterday.
At the time of this report, the winds blow from the northwest.
Continuous degassing is observed when weather conditions permit. Today, at 2 o’clock in the morning, we observed an incandescence in the active crater.

The activity was weak during the week, dominated by a plume of gas and water vapor and a record number of long-duration low-amplitude seismic events. Incandescence is observed occasionally and with varying intensity. On the night of April 23rd at 9:08 pm, lightning was observed in the volcanic monitoring chamber of the RSN. These flashes were produced by a meteor that crossed the national territory.

Rincon de la Vieja Volcano:
No eruption is reported.
The seismic activity is similar to that of yesterday.
The wind direction is unknown at the moment.
It is possible to observe tremors in seismic signals, but no eruptions have been reported.

In the photo, the active crater is observed on its northern flank on April 17. Photograph provided by Joaquín Matarrita.

The predominant seismic activity this week is long-period type signals and volcano-tectonic signals (less than a dozen). In addition, a continuous and pulsating spasmodic tremor was recorded during the week with variations in amplitude and duration.

Turrialba Volcano:
No eruption is reported.
The seismic activity is similar to that of yesterday.
At the time of this report, the winds blow from the northeast.
Today at 7:22 am a small eruption of short duration and with ash emission was observed; the column did not reach 100 m of altitude above the summit of the volcano.

Like the previous week, the Turrialba volcano maintains a weak and stable activity. Recording of long period (LP) events is maintained.

Sources : OVSICORI-UNA, RSN.

Photos : Ovsicori , Joaquín Matarrita , Rsn .

New Zealand , Ruapehu :

Te Wai ā-moe, Mt Ruapehu crater lake is starting to cool and seismic activity decreases.

Volcanic Alert BulletinVOLCANIC ALERT BULLETIN: RUA– 2019/02 , Mon Apr 29 2019 4:00 PM;

Volcanic Alert Level remains at 1
Aviation Colour Code remains at Green

The period of high lake temperatures at Te Wai ā-moe (Crater Lake), Mt Ruapehu along with moderate levels of volcanic tremor has now passed. We are now moving away from a range of higher probability of eruption in this heating phase. The Volcanic Alert Level remains at 1.

On April 10th we reported the lake temperature was rising and the tremor intensity was moderate. The lake temperature reached a peak of 44 °C on 19th April and is now 39 °C and continues to cool. The level of volcanic tremor has declined since 16th April and is now classified as weak.
In early April the lake temperature was trending towards a range thought to be associated with higher probabilities of an eruption. These probabilities are based on our understanding of Ruapehu’s long term relationship between volcanic activity and the lake temperature. The decreasing lake temperature indicates we are now moving away from this range of higher probability of eruption in the short term.
Last week some small steam plumes were observed above the lake. These can still be expected while the lake remains relatively warm and the air temperature cools as winter approaches.
Volcano Alert Level 1 corresponds to minor unrest. While this is the case, it is a useful reminder that eruptions can occur with little or no warning. GNS Science continues to closely monitor Mt Ruapehu and our other active volcanoes and will provide further information when conditions change.

Source : Geonet / Craig Miller , Duty Volcanologist

Photo : Geonet.

Indonesia , Soputan :

Level of Activity at Level III (SIAGA) . Gunungapi Soputan (1809 m) has increased volcanic activity.

Since yesterday and until this morning, the volcano was clearly visible until it was covered with fog. The smoke from the crater was observed at a height of 20 meters, white color and low intensity.

With seismographs dated April 28, 2019, it was recorded:
12 avalanche earthquakes
4 earthquakes of explosion.
1 volcanic earthquake (VA)
4 distant tectonic earthquakes

Recommendation:
The community must not have activities within a radius of 4 km around the summit of G. Soputan and in the area of the West-Southwest sector up to 6.5 km, which constitutes the crater opening area. , to avoid the threat of avalanches and hot avalanche clouds.

Source : PVMBG.

Photo : Archive , unknown author.