July 16 , 2017. EN. Piton de la Fournaise , Mount Curry , Turrialba , Poas , Sangeang Api .
July 16 , 2017.
Piton de la Fournaise , La Réunion :
Activity Report for Saturday, July 15, 2017 at 4:30 pm (Local Time)
The eruption begun on July 14 at 00:50 local time continues. The volcanic tremor (surface eruptive indicator) decreased by a factor of 7 compared to the beginning of the eruption and remains constant at 10h local time (6h UTC hour, Figure 1).
Figure 1: Evolution of the RSAM (volcanic tremor and eruption intensity indicator) between 00:00 (20h UTC) and 16h00 (12h UTC) on July 15th on the RVL seismic station, located on the southern flank of the volcano . (© OVPF / IPGP)
– No significant deformation was recorded during the day on the terminal cone.
– No seismicity was recorded during the day under the Piton de la Fournaise building.
The decrease of the eruptive tremor is reflected on the ground by a reduction of the flows and the distribution of the activity on the eruptive crack. In comparison with the 7 lava fountains observed during the day of July 14, there are only 3 lava fountains that are active on the most downstream part of the eruptive crack. These lava fountains begin to form two small volcanic cones, the lava flows of which merge into a single channel (Figure 2). The height of the lava fountains does not exceed 30 meters.
Figure 2: Shooting of the eruptive site on July 15, 2017 at 2:00 pm, local time. (© OVPF / IPGP)
Following a survey conducted around 2 pm with the assistance of the Gendarmerie Air Section, the flow front was located approximately 2.2 km east-southeast of the eruptive site (Figure 3).
Figure 3: Location of the eruptive fissure which opened on July 14, 00h50 local time and from the front of the casting to July 15, 14h local time (background image: GoogleEarth). (© OVPF / IPGP)
Estimates carried out using satellite methods via the HOTVOLC platform (OPGC – Clermont Ferrand) show a minimum flow rate of about 2 m3 / s.
It should be noted that this evolution towards a decrease in flows and a focus of eruptive activity at the most downstream point of the eruptive fissure is a usual process observed during the eruptions of the Piton de la Fournaise.
Source : OVPF
Photo : Serge Gelabert
Mont Curry , South Sandwich Islands :
South Sandwich Islands Volcano Monitoring Blog , Thursday, 13 July 2017
Possible eruption on Mount Curry.
A light grey plume is seen drifting in a northerly direction in the satellite image from 13th July 2017 originating from Mount Curry Volcano on the northern side of Zavodovski Island. As this plume looks like it is coming from the crater area of Mount Curry, I am under the opinion that there’s a good chance that this could be an ash plume indicating that an eruption took place.
Possible ash plume from Zavodovski Island, drifting north on 13 July 2017. SOURCE: Terra / MODIS / NASA
The 5-km-wide Zavodovski Island, the northernmost of the South Sandwich Islands, consists of a single basaltic stratovolcano with two parasitic cones on the east side. Mount Curry, the island’s summit, lies west of the center of the island, which is more eroded on that side. Two fissures extend NE from the summit towards the east-flank craters, and a lava platform is located along the eastern coast.
Zavodovski is the most frequently visited of the South Sandwich Islands. It was erupting when first seen in 1819 by the explorer Bellingshausen, and the volcano has been reported to be smoking during subsequent visits.
Source : Blog de surveillance du volcan des îles Sandwich du Sud , GVP.
Turrialba , Poas , Costa Rica :
Activity report of the Turrialba and Poas Volcanoes, 15 July 2017 – 11h00.
Ashes erupted yesterday afternoon at 18:35. The pyroclast column reached a height of about 300 meters and was moved westward by wind. Another ash eruption occurred today at 05:00, which lasted until about 09:00. The gases and column of pyroclasts reached 300 meters above the crater and the wind turned northwest.
Then another small ash eruption occurred today at 10:25. The column reached 300 meters high and the wind dissipated it to the southwest. And finally, another eruption of ashes arrived today at 10:58. The column reached 400 meters high and the wind dissipated it to the southwest.
Ash falls have been reported in: Sabanilla de Montes de Oca, Ipis, El Carmen de Guadalupe, Purral, Guadalupe, Tibas. An odor of sulfur was felt in San Jose, Turrialba, Guadeloupe, Escazu and Puriscal. The seismic activity exhibits low intensity tremor signals and low frequency earthquakes (Lp).
The volcano still maintains an activity of exhalations and fumaroles in the crater, producing a strong degassing. The column of gas reached heights up to 500 meters above the crater.
The wind moved it to the southwest and northwest.
There are reports odor of sulfur in the cities of Grecia and San Juan de Naranjo. The seismic signal has few low frequency Lp seisms. The tremor signal has a moderate amplitude.
Source : Ovsicori
Sangeang Api , Indonesia :
Volcano Observatory Notice for Aviation (VONA):
Last Issued: 2017 , July 15 .
Current Aviation Color Code: ORANGE
Volcanic Activity Summary:
Small eruption with ash emission 100-200 m above summit at 03:54 UTC (11:54 LT).
Volcanic Cloud Height:
Best estimate of ash-cloud top is around 6877 FT (2149 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer.
Other Volcanic Cloud Information:
Ash moving to southwest
Seismic activity is characterized by frequent harmonic tremor.
The level of activity of G. Sangeang Api is at level II (Waspada)
The communities around G. Sangeang Api and the visitors / tourists are not allowed to approach and have activities within a 1.5 km radius of the activity center of G. Sangeang Api.
The communities around G. Sangeang Api and visitors / tourists should be aware of the danger of pyroclastic flows and are not allowed to approach and move in the area between the Sori Sori valley and Wala Mantau to reach the beach, In Boro and Sori Sori Valley Oi.
The public, farmers, visitors / tourists are not allowed to approach and travel on all valleys of rivers that discharge from the G. Sangeang Api business center to avoid the potential threat of lahars that may occur during rains.
Sangeang Api volcano, one of the most active in the Lesser Sunda Islands, forms a small 13-km-wide island off the NE coast of Sumbawa Island. Two large trachybasaltic-to-tranchyandesitic volcanic cones, 1949-m-high Doro Api and 1795-m-high Doro Mantoi, were constructed in the center and on the eastern rim, respectively, of an older, largely obscured caldera. Flank vents occur on the south side of Doro Mantoi and near the northern coast. Intermittent historical eruptions have been recorded since 1512, most of them during in the 20th century.
Sources : VSI , Magma , GVP.
Photo : dxnews.com