Friday 13 May 2022

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 4 May – 10 May 2022

Aira- Kyushu (Japan) : JMA reported that sulfur dioxide emissions at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) were slightly high at 500 tons per day on 2 May. At 1453 on 3 May an eruption produced a plume that rose 1.1 km above the crater rim. Very small eruptive events were recorded during 6-9 May.

Dukono – Halmahera : Based on satellite and wind model data, the Darwin VAAC reported that during 4-9 May ash plumes from Dukono rose to 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted in multiple directions.

Great Sitkin – Andreanof Islands (USA) : AVO reported that slow lava effusion at Great Sitkin likely continued during 3-10 May; a 5 May satellite image showed that the S flank flow had advanced 15 m. Elevated surface temperatures were identified in satellite data during 6-10 May.

Kavachi – Solomon Islands : Satellite data showed discolored water around Kavachi on 10, 20, 25, and 30 April as well as on 5 May.

Kilauea – Hawaiian Islands (USA) : HVO reported that lava continued to effuse from a vent in the lower W wall of Kilauea’s Halema`uma`u Crater during 3-10 May, entering the active lava lake and flowing onto the crater floor. The surface of the lava lake was active all week, though the height of the lake was relatively stable. Daily breakouts occurred along the NE, NW, and S margins of the lake. A short-lived lava flow effused from the W vent and onto the crater floor at around 0700 on 7 May.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok continued during 4-10 May. Eruptive events at 1245 on 4 May and 0544 on 6 May produced ash plumes that rose 600 m above the summit and drifted W.

Manam – Northeast of New Guinea : The Darwin VAAC reported that during 3-4 May ash plumes from Manam rose to 2.1 km (7,000 ft) a.s.l. and drifted SE and NW based on information from RVO, satellite images, and weather models. On 6 May ash plumes rose to 1.8 km (6,000 ft) a.s.l. and drifted NW and WNW.

Merapi – Central Java : BPPTKG reported no significant morphological changes at Merapi’s summit lava dome during 29 April-5 May, though the height of the dome below the SW rim had decreased by around 3 m. Based on photo analyses, the volume of the SW lava dome had a volume of 1.52 million cubic meters while the central lava dome was 2.58 million cubic meters. As many as 120 lava avalanches traveled a maximum of 2 km, mostly down the Bebeng drainage on the SW flank. Seismicity remained high.

Nevado del Ruiz – Colombia : On 10 May Servicio Geológico Colombiano’s (SGC) reported that during the previous week the number of seismic signals indicating both rock fracturing and fluid movement at Nevado del Ruiz had increased compared to the week before. Several episodes of drumbeat seismicity were recorded on 5 and 8 May, indicting growth of the lava dome. Some low-temperature thermal anomalies were also identified at Arenas Crater. Gas-and-ash emissions were periodically visible in webcam images. A small ash emission on 3 May caused minor ashfall in the municipalities of Manizales (25 km N), Dosquebradas (40 km W), Santa Rosa, and Pereira (40 km WSW). At 0857 on 9 May an ash plume drifted NW, W, and SW, causing ashfall in Manizales, Villamaría (28 km NW), and Chinchiná (30 km WNW) in the department of Caldas, and in Pereira, Dosquebradas, and Santa Rosa de Cabal (33 km W) in the department of Risaralda.

Pavlof – Alaska Peninsula, Alaska : AVO reported that the eruption at a vent on Pavlof’s upper E flank was ongoing during 3-10 May, though weather conditions sometimes prevented visual observations. Seismic tremor persisted. Daily elevated surface temperatures were identified in satellite images and almost daily steam emissions were recorded in webcam images. The lava flow from the E vent was 500 m long by 8 May.

Rincon de la Vieja – Costa Rica : On 5 May OVSICORI-UNA reported an average of two daily phreatic explosions at Rincón de la Vieja during the previous week. The events did not eject material outside of the crater and produced steam plumes that rose no higher than 200 m above the crater rim. A phreatic explosion at 1650 on 6 May produced a steam plume that rose 500 m. A few phreatic explosions and several steam emissions were recorded on 7 May. Several steam emissions were also recorded on 8 May.

Ruapehu – North Island (New Zealand) : On 11 May GeoNet reported that elevated unrest at Ruapehu continued during the previous week, consisting of lake water heating, volcanic gas output, and strong volcanic tremor. The lake water temperature continued to rise, peaking at 41 degrees Celsius. Steam plumes were visible rising from the lake; an overflight confirmed that they were caused by a combination of the warming lake and atmospheric conditions, with no eruptive activity. Tremor levels declined but remained high. A gas measurement flight on 4 May confirmed high levels of gas emissions with sulfur dioxide and carbon dioxide flux rates at 260 and 1,970 tonnes per day, respectively. Lake upwelling over the central and northern vents areas was also visible during multiple overflights. The sustained carbon dioxide and sulfur gas emissions, along with high tremor levels, continue to indicate that magma is driving this period of heightened unrest.

Sabancaya – Peru : Instituto Geofísico del Perú (IGP) reported moderate levels of activity at Sabancaya during 2-8 May with a daily average of 53 explosions. Gas-and-ash plumes rose as high as 3 km above the summit and drifted N, NE, E, and SE. As many as five thermal anomalies originating from the lava dome in the summit crater were identified in satellite data. Minor inflation continued to be detected near Hualca Hualca (4 km N).

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 3-10 May. Ash plumes visible on 5, 7, and 9 May were rising 400-700 m above the summit and drifting mainly SW.

Semisopochnoi – Aleutian Islands (USA) : AVO reported that low-level eruptive activity at Semisopochnoi’s North Cerberus cone continued during 3-10 May. Seismicity continued to be elevated with intermittent tremor detected by the seismic network. Several daily explosions were recorded during 8-10 May. Weather clouds obscured views of the volcano, though daily minor, low-level ash emissions were seen in webcam views. A pilot reported a low-level eruption cloud on 9 May.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 29 April-6 May, and lava-dome extrusion continued.

Stromboli – Aeolian Islands (Italy) : INGV reported that during 2-8 May activity at Stromboli was characterized by ongoing explosions from three vents in Area N (North Crater area) and two vents in Area C-S (South-Central Crater area). Explosions from Area N vents (N1 and N2) averaged 3-6 events per hour; explosions from the N1 vent ejected lapilli and bombs mixed with ash 80-150 m high and those at two N2 vents ejected material less than 80 m high. N2 produced weak and occasional spattering. No explosions occurred at the S1 and C vents in Area C-S; low-intensity explosions at the two S2 vents occurred at a rate of 1-5 per hour and ejected coarse material no higher than 80 m.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that eruptive activity continued to be recorded at Suwanosejima’s Ontake Crater during 2-9 May. Eruption plumes rose as high as 1.3 km above the crater rim; no explosions were recorded. Crater incandescence was occasionally visible during 2-6 May and ash fell in Toshima village (3.5 km SSW).

Whakaari/White Island – North Island (New Zealand) : On 9 May GeoNet reported that activity at Whakaari/White Island remained at a low level based on observations and data collected during an overflight conducted on 27 April. Gas-and-steam emission temperatures were up to 111 degrees Celsius, down from 16 March highs of 288 degrees Celsius. Geysering activity at one of the water-saturated vents was observed. Satellite data indicated minor uplift in the active vent area. Seismicity was low.

Wolf – Isla Isabela (Galapagos) : On 5 May IG reported that the eruption at Wolf’s SE flank was over. The eruption began at 2320 on 6 January from an approximately 8-km-long radial fissure, trending NW-SE, that had at least five active vents. Lava flows from the vents traveled SE then E, covering an area of more than 30 square kilometers. The maximum length of the flow field was 18.5 km, with the farthest-reaching flow stopping 150-200 m from the coastline. The highest levels of heat, sulfur dioxide emissions, seismicity, and deformation were recorded in the early days of the eruption. Sulfur dioxide emissions had been absent for the previous 30 days.



from WordPress https://ift.tt/rHXgzNa

No comments:

Post a Comment