June 03 , 2016. EN. Turrialba , Mauna Loa , Nyiragongo , Bristol Island .
June 03 , 2016.
Turrialba , Costa Rica :
Activity report of the Turrialba volcano
Updated Thursday, June 2, 2016 at 6:33 p.m..
The eruption of 1 June 2016, began at 10:40 p.m. lasted 1 hour 50 minutes.
The current eruption began on June 2 at 0:37, lasted six hours consistently, at the time of this report update (6:33 a.m.) (see seismogram attached).
Ash and gas probably move to the northwest according to the IMN station located above the Turrialba volcano at 3,300 meters.
June 2, 2016 at 21:00.
After 5 days of « relative calm« , ash emissions occur again on June 1, 2016, at 10:40 p.m. with sustained activity. The main impulses occurred at 10:40 p.m. June 1, 0:37, 5:13 and 5:45 Saturday, June 2 The ash emissions continue during the drafting of the report.
The seismic activity is characterized by a spasmodic tremor (variable amplitude) from 10:10 p.m. June 1
The emission cloud reached 2000 m above the volcano (5300 m) at 5:20 and 06:00. The direction of variable dispersion, mainly to the north, the Northwest and the Northeast was observed by cameras. The model AERMOD foresee a dispersion toward the west and northwest.
Possible ash falls were reported in:
Heredia Santa Lucía de Barva, Heredia Santo Domingo, San Francisco de Heredia, San José Tibás, perhaps Moravia.
A slight smell of sulfur is reported in La Sabana, Alajuelita, San Rafael de Escazu and Coronado.
Source : Ovsicori
Mauna Loa , Hawai :
19°28’30 » N 155°36’29 » W,
Summit Elevation 13681 ft (4170 m)
Current Volcano Alert Level: ADVISORY
Current Aviation Color Code: YELLOW
Mauna Loa is not erupting. A small earthquake swarm occurred beneath Mauna Loa’s west flank from Saturday, May 28 through Tuesday, May 31. Most of the earthquakes occurred at depths between 5-8 km (3-5 mi) below the surface and the largest event was a magnitude 2.8. This activity is part of the expected range of behaviors for Mauna Loa and does not represent a significant change.
View from just below the summit of Mauna Loa looking back down the Southwest Rift. The Sulfur Cone is the white area just above center frame. Puʻu o Keokeo is the barely visible bump just above Sulfur Cone at the crest of the Southwest Rift.
Seismicity rates have since decreased, though are nonetheless elevated above the long-term background. Global Positioning System (GPS) measurements continue to show deformation related to inflation of a magma reservoir beneath the summit and upper Southwest Rift Zone, with inflation recently occurring mainly in the southwestern part of the magma storage complex.
Source : HVO
Nyiragongo , Democratic Republic of Congo :
The Volcanological Observatory of Goma (OVG) informs people of Goma, Gisenyi and elsewhere as instrumental data acquired during the period from May 16 to 22 indicate that:
Overall, magmatic earthquakes are located in the fields of both Virunga volcanoes (Nyiragongo and Nyamulagira), with an average of 9 per day.The magmatic earthquakes located in the Nyamulagira volcano field are mainly located on the East side and in the central crater at depths ranging between 0 / 5km and 15 / 25km. Regarding RSAM values, a maximum of 1,200 units was recorded dated on May 19, 2016.
About the thermal emission of the two volcanoes, the situation is as follows:
For Nyamulagira: no disturbing thermal anomalies observed.
– The normalized thermal index was low, less than 0.8
– The change in the average of radiative power was low.
For the Nyiragongo: no disturbing thermal anomalies observed.
– The normalized heat index was low, less than 0.8
– The change in the average radiative power was low
On geothermal fractures:
-The Temperatures in fractures located on the southern flank of Nyiragongo and in Goma during the reporting period do not indicate variations notables. There is no thermal anomalies and we report a certain stability. Regarding the sites at the top of Nyiragongo, we observed a situation similar to Shaheru and Nyiragongo huts. But, there is a slight drop in temperature , about 2 degrees, on the site Nyiragongo summit from 27 ° C to 25 ° C this week.
The variation of the carbon dioxide (CO2) at the fracture remains low in the sites of Munigi and Bugarura, although a slight increase in Munigi and Bugarura 2, respectively ranging from 0.1% to 1.2 % to Munigi between 13 and 20 May and 0.2% to 1.2% to Bugarura 2 for the same period.
Source : OVG Goma.
Photo : Jeremie Franchitti , Virunga.org.
Bristol Island , South Sandwich Islands (UK):
Elevation 1100 m
According to NASA’s Earth Observatory, a Moderate Resolution Imaging Spectroradiometer (MODIS) satellite image of Bristol Island acquired on 28 May showed an ash plume from Mt. Sourabaya drifting NE. Based on satellite image analysis, the Buenos Aires VAAC reported that during 29-31 May gas plumes with possible minor ash content drifted as far as 185 km N, NNE, and SE at an altitude of 1.5 km (5,000 ft) a.s.l.
The 9 x 10 km Bristol Island near the southern end of the South Sandwich arc lies across Fortser’s Passage from the Southern Thule Islands and forms one of the largest islands of the chain. Largely glacier-covered, it contains a horseshoe-shaped ridge at the interior extending northward from the highest peak, 1100-m-high Mount Darnley. A steep-sided flank cone or lava dome, Havfruen Peak, is located on the east side, and a young crater and fissure are on the west flank. Three large sea stacks lying off Turmoil Point at the western tip of the island may be remnants of an older now-eroded volcanic center. Both summit and flank vents have been active during historical time. The latest eruption, during 1956, originated from the west-flank crater, and deposited cinder over the icecap. The extensive icecap and the difficulty of landing make it the least explored of the South Sandwich Islands.
Sources: NASA Earth Observatory, Buenos Aires Volcanic Ash Advisory Center (VAAC), GVP.