June 30 , 2017. Nevado Del Ruiz , , Bogoslof , Lō’ihi , Poas .

Home / Alaska / June 30 , 2017. Nevado Del Ruiz , , Bogoslof , Lō’ihi , Poas .

June 30 , 2017. Nevado Del Ruiz , , Bogoslof , Lō’ihi , Poas .

June 30 , 2017.

 

Nevado Del Ruiz , Colombia :

Weekly activity bulletin of the volcano Nevado del Ruiz, from June 20 to June 26, 2017
The level of activity continues: at the level of yellow (III) activity: changes in the behavior of the volcanic activity.

As regards the monitoring of the activity of the Nevado del Ruiz volcano, the Colombian Geological Survey reports that:

Over the past week, the various monitoring parameters indicate that the Nevado del Ruiz volcano continues to exhibit unstable behavior.

 

The seismicity caused by the fracture of the rock showed a decrease in the number of recorded earthquakes and seismic energy released compared to the previous week. The earthquakes were mostly in the south-west, south-east, and near Arenas crater, and to a lesser extent in the northwest and northeast regions, at depths between 1, 4 and 6.7 km. The maximum magnitude recorded during the week was 1.1 ML (local magnitude), which corresponds to an earthquake recorded on 22 June at 01:23 (local time), located southwest of the Arenas crater at a depth of 3.8 km.

The seismic activity associated with the fluid dynamics inside the volcanic structure ducts showed a decrease in the number of recorded earthquakes and a slight increase in the seismic energy released compared to the previous week. This type of activity is mainly characterized by the occurrence of several seismic fluids events, long period and very long period events and tremor pulses with varying energy levels and durations. Some of these seismic signals have been associated with emissions and ash in the atmosphere, as confirmed by the cameras installed in the volcano region and the reports of the PNNP officials. The recording of seismic signals of this type, with higher energy levels, which may be associated with emissions of gases and ash are not ruled out. It is important to remember that the ash emission processes can occur for several days and sometimes several times during the day, without involving an individual report for each episode.

 

Volcanic deformation, measured from electronic inclinometers, Global Navigation Satellite Systems (GNSS) and satellite imagery to determine changes in inclination, position and shape of the volcano continues to record over a deflationary process and intermittent inflation / deflationary impulses linked to gas and ash emissions.

The volcano continues to emit large quantities of water vapor and gases, including sulfur dioxide (SO2), as shown by the values ​​obtained by the SCANDOAS stations installed in the volcano area and the volcano, Satellite image analysis. In the follow-up information provided by the NASA and FIRMES Mírová website, no thermal anomaly was identified during the week.

The column of gas, steam and ash from time to time reached a maximum height of 1400 m measured on the top of the volcano on June 20th. The direction of dispersion of the column was governed by the direction of the wind in the zone which, during the period, was predominant towards the north-east.

The volcano Nevado del Ruiz continues to activity level Amarillo.

 

Source : SGC

 

Bogoslof , Alaska :

AVO/USGS Volcanic Activity Notice

Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Issued: Thursday, June 29, 2017, 5:55 PM AKDT
Source: Alaska Volcano Observatory
Location: N 53 deg 55 min W 168 deg 2 min
Elevation: 492 ft (150 m)
Area: Aleutians

 

 

Volcanic Activity Summary:
An eruption began at Bogoslof volcano at 01:24 UTC on June 30 (17:24 AKDT on June 29). Seismicity returned to background at 01:45 UTC (17:45 AKDT) indicating an end or pause to the explosion. No ash cloud has been detected as of yet in satellite data, but infrasound signals recorded from Bogoslof suggest volcanic ash emissions likely occurred. Winds are towards the north.

We are evaluating the magnitude of this eruptive episode. The Aviation Color Code remains at ORANGE and the Volcano Alert Level remains at WATCH at present. AVO is evaluating all data sources and will update this report as more information becomes available.

Recent Observations:
[Volcanic cloud height] None detected yet. NWS eruption SIGMET issued. Unknown height
[Other volcanic cloud information] Winds to the north
[Lava flow/dome] N/A
[Lava flow] N/A

Remarks:
The National Weather Service Alaska Aviation Weather Unit has issued an eruption SIGMET warning for aviation. This may be revised as new information becomes available. Please see the NWS AAWU at http://www.weather.gov/aawu/ for updated information on aviation warning messages.

 

Source : AVO

 

Lō’ihi , Hawaï :

Activity At Underwater Volcano Loihi Increases.

29 JUNE 2017. Earthquakes are on the uptick at the Hawaiian Island chain’s youngest and still submarine volcano. Lō‘ihi, centered 24 miles southeast of Pāhala in Hawai‘i County’s Ka‘ū District, has been home to recent increases in seismic activity. And in the last two days, the number of earthquakes recorded at the seamount has doubled the number logged over the last 2 to 4 weeks.

The increase in seismicity was the subject of a recent USGS Hawaiian Volcano Observatory Volcano Watch article. The scientists have been tracking earthquake activity at Lō‘ihi from land-based seismic stations for over 50 years. The article was published on June 22.

Indeed, since the end of February 2017, HVO seismic analysts have noted a slight uptick in the numbers of earthquakes near Lō‘ihi. From January 2015 through February 2017, there was, on average, one located Lō‘ihi earthquake per month. Since then, the rate of earthquakes has gradually increased. This month alone (as of June 22), there have been 51 located earthquakes in the Lō‘ihi region.

Without permanent seismic stations at Lō‘ihi—because the highest point of the volcano is still a kilometer (0.6 mi) under water—it is not possible to locate earthquakes there as accurately as we can at Kīlauea or Mauna Loa. However, we can state that the June 2017 earthquakes appear to be clustered roughly 10–12 km (6–7 mi) below sea level and extend from beneath the summit region of Lō‘ihi to the south.

 

IMAGE: Left: A color-shaded bathymetry map of Lō‘ihi, a submarine volcano located southeast of the Island of Hawaiʻi. The summit region is marked by pit craters formed in connection with an eruption and earthquake swarm in July–August 1996. Right: Earthquakes in the vicinity of Lō‘ihi (same area as bathymetry map) located by the USGS Hawaiian Volcano Observatory during a 30-day period ending June 22, 2017. Locations of the earthquakes are shown with dots; size indicates magnitude and color indicates time (blue represents earthquakes within two days of June 22, yellow within two weeks, and white within four weeks). For example, the blue dot east of Lō‘ihi was a magnitude-2.3 earthquake that occurred on June 22.

Interestingly, the roughly 170 earthquakes located in the area of Lō‘ihi between 2010 and 2016 occurred away from the summit region. They were primarily beneath the northern flanks of Lō‘ihi, and extended to significantly greater depths below the volcano. The significance of this difference is unclear.

As early as 1952, HVO scientists interpreted occasional earthquake swarms in the Lō‘ihi region as reflecting active volcanism there. In fact, the earthquakes were key to recognizing that the seamount is actually an active volcano!

Earthquake activity alone does not conclusively indicate that Lō‘ihi is erupting. But the locations of recent earthquakes directly beneath the volcano’s summit region plausibly suggest magmatic or volcanic origin, such as adjustments within the magma reservoir or volcanic edifice. We would, however, expect to see many more earthquakes associated with an eruption.

The most recent confirmed eruption of Lō‘ihi occurred in 1996. That year, an energetic earthquake swarm began in July and quickly intensified, motivating a scientific expedition to Lō‘ihi to seize an unprecedented opportunity to possibly observe a submarine eruption. Thousands of earthquakes, including over a dozen with magnitudes greater than 4.5, were recorded from beneath the summit and south flank of the volcano between July and September 1996.

Subsequent viewing and mapping of the Lō‘ihi summit region showed that, consistent with magma movement from beneath the summit area, a significant portion of it had collapsed. Fresh pillow lavas and glassy fragments collected during submersible dives also confirmed the occurrence of an eruption.

Because Lō‘ihi is still so deep beneath the ocean’s surface, the USGS regards Lō‘ihi as a low- to very low-threat volcano. Thus, there are no immediate plans for additional monitoring instruments and our views of Lō‘ihi for the foreseeable future will be strictly seismological.

Today, two of the earthquakes measured at Lō‘ihi were a Magnitude 3.0 and 3.1, with several more having occurred over the last two days measured between Magnitude 2.9 and Magnitude 1.9.

It’s not known when Lō‘ihi will breach sea level, scientists say. They speculate that with a growth rate of a little over 16 feet per one thousand years, it will take as much as 200,000 years to reach the ocean surface.

 

Source :  BIVN

 

Poas , Costa Rica :

Activity Report of the Poas Volcano on 29 June, 2017, updated at 11:00

Poas volcano seismographs recorded a continuous low – to – moderate amplitude signal (within the last 24 hours) associated with fluid flow within the volcano and emission of gases, vapor and particles through the mouths at the bottom of the crater). There were also discrete high-frequency volcano-tectonic events (VT, associated with rock fracturing or internal collapse).

 

During the morning, it was not possible to estimate the height of the plume, given the weather conditions. The cloud of steam, gases and aerosols was dispersed mainly to the southwest of the crater. Issues could potentially affect areas such as Poas Volcano National Park, Animas, Alajuela, San Pedro de Poas, Altura, Villa Inés, Cabuyal, Naranjo, San Ramon, Esquipulas, Palmares, Cirri, Grecia, Tacares, Zarcero, Bajos Del Toro, Laguna, Picado, Alto Palomo, among other places nearby.

An intense incandescence continues to be observed in the crater at night through the webcams. He reported a strong odor of sulfur in San Rafael de Poas. The inhabitants say that the community of Vara Blanca perceives it mainly in the morning.

 

Source : Ovsicori

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