UN peace keepers in the Democratic Republic of Congo provided volcanologists an early May helicopter flight. This presented very clear views of Nyiragongo, including the scene inside the active crater. Viewers reported seeing a significant plume containing gas and ash rising high above the volcano.
A report issued on 2 May noted an inferred renewal of activity on Nyamuragira. Residents living in the villages of Katale and Tongo, the settlements closest to the volcano, reported rumblings on 30 April, in addition to clear noises of individual explosions. At the same time on 30 April the closest seismic station (Katale) recorded 18 clear explosion signals, directly followed by an important tectonic earthquake located beneath the volcano.
KVERT reported above-background seismicity at Kliuchevskoi during the week ending 1 May. Specifically, there were 25 earthquakes over M 1.25 at ~30 km depth, and 19 earthquakes over M 1.25 at shallower depths, including some within the edifice. In addition, during the same week instruments registered numerous weak, shallow earthquakes, and continuous spasmodic tremor.
Lava flows continued to descend the S flanks and pour into the sea. Distances measured across Kilauea caldera between two points ~10 km apart, remained stable as they have since early 2003. There had been consistent progressive lengthening of this distance during late 2001 through mid-2002, and some minor fluctuations after that.
This week Guagua Pichincha was marked by low-to-modest seismicity, which included earthquakes on 30 April and 1 May with magnitudes less than 3. Both had epicenters within an earthquake swarm N of Quito. Episodes of harmonic tremor appeared, most noteworthy on 4 and 5 May with each episode lasting under 40 minutes.
At the end of April U.S. Air Force meteorologists used GOES-12 imagery to describe a thin plume of Fuego's ash that rose to ~7 km a.s.l. and blew SW at 20-30 km/hour.
In the midst of an interval of ongoing tranquility, small explosive eruptions came from Colima on 2 May generating minor ash clouds visible on satellite imagery and local video monitoring. The ash clouds apparently rose no more than about 500 m above the crater.
Chikurachki began erupting on 18 April 2003 and the eruption was clearly continuing through 25 April. Associated ash plumes were over 100 km long.
Wed, 23 Apr 2003, 06:00
A 25 April report on Shiveluch from KVERT stated that, based on seismic data a hot pyroclastic avalanche possibly took place on 23 April. Also, a M 2.25 earthquake occurred this day. Intermittent spasmodic volcanic tremor registered all week.
Read allWed, 23 Apr 2003, 06:00
A landslide on the outer flanks of Tolimán volcano passed through and buried portions of a mountain village at 0418 on 23 April. Regional authorities blamed steep slopes, wet soils, and minor tremors. The disaster struck the village of Chichicaste, which lies along the volcanic front ~300 km W of the capital, Guatemala City.
Read allWed, 23 Apr 2003, 06:00
On 24 April at 2050 Popocatépetl issued a moderate explosion that threw incandescent fragments 1.5-2.0 km above the crater and generated an ash column that rose to ~2.5 km above the crater. The plume was initially carried E. This activity was related to the destruction of a small dome that formed in the past few days.
Read allWed, 23 Apr 2003, 06:00
A KVERT report on Kliuchevskoi issued on 25 April stated that above-background seismicity, including abundant tremor, prevailed during the week. This report also revealed that the ash explosions of 17-18 April had sent material 1-2 km above the crater. Modest thermal anomalies registered in satellite data for 18-19 April and plumes around that time extended E for 20-200 km.
Read allWed, 23 Apr 2003, 06:00
For the week ending 29 April eruptive activity continued unabated from the Pu`u `O`o vent of Kilauea. The flows on Pulama pali were frequently visible at night as streams of incandescence from the top of the pali down to the coastal flats. Late in the previous week and early in this week, the east arm of the Mother's Day flow split in two with the western segment being more active.
Read allWed, 23 Apr 2003, 06:00
KVERT reported that Karymsky's seismicity was above background during the week ending 25 April, an interval when instruments registered ~40-100 volcanic earthquakes per day. The character of the seismicity suggested ash-and-gas explosions up to 1,000 m above the volcano's crater. According to Russian satellite data, ash deposits were detected ~35 km away in various directions from the volcano; these were noted the previous week, on 19-22 April, but not previously reported here.
Read allWed, 23 Apr 2003, 06:00
During the week Guagua Pichincha continued to display seismic unrest, typically with several earthquakes per day but including 16 long-period earthquakes on 26 April. During 23, 24, 26, and 27 April observers on the mountain typically smelled sulfur, but qualitative assessments of fumarolic output varied. In conditions of poor visibility, observers sometimes heard the sound of gases escaping in the crater.
Read allWed, 23 Apr 2003, 06:00
The Washington VAAC reported that on 28 April Fuego produced intermittent ash eruptions. One cloud was observed at ~ 7 km a.s.l., traveling SW at 19-29 km per hour. Although remote sensing was complicated by poor visibility due to high cirrus clouds and smoke from fires, some eruptive puffs remained recognizable when they blew over the coast.
Read allWed, 23 Apr 2003, 06:00
Chikurachki, a volcano located on Paramushir Island in the North Kuriles, began erupting on 18 April 2003. A KVERT update for 25 April stated that the eruption continued and satellite data confirmed that ash plumes had moved SE and occasionally E during 22-25 April. The plumes attained lengths over 100 km.
Read allWed, 16 Apr 2003, 06:00
Although activity was generally low during the week of 16-22 April, more volcanic explosions continued at Tungurahua. Many of these events were small, and minor vapor columns were also noted. Cloud cover obscured the volcano on some days.
Read allWed, 16 Apr 2003, 06:00
Chikurachki stratovolcano, located on Paramushir Island in the Northern Kuriles, began erupting on 18 April 2003. During the next few days observers described the ash falls and substantial plumes with estimated heights up to ~10 km altitude. Observers on Paramushir island saw ash explosions on 18 April; ash fell in Podgorny town and Cape Vasiliev.
Read allWed, 16 Apr 2003, 06:00
During 16-22 April, dome extrusion continued at Soufrière Hills. Poor visibility prevailed for parts of the week, but seismicity and SO2 fluxes remained significant. Numerous rockfalls and pyroclastic flows have occurred on the eastern flanks of the dome in the Tar River Valley.
Read allWed, 16 Apr 2003, 06:00
During the week of 16-22 April, Semeru was continually active. A white-gray ash plume@ rose 400-500 m over the summit. Seismic signals interpreted as pyroclastic flows were recorded multiple times during the week.
Read allWed, 16 Apr 2003, 06:00
The ongoing eruption at Popocatépetl was punctuated by a small explosion on 17 April, an event accompanied by incandescent fragments that reached 1 km E along the summit crater=s outer margin, and a modest ash plume directed toward the NE. Associated with the event, low-amplitude tremor persisted for about 2 hours, but no other significant geophysical changes were seen. More typical low-intensity outbursts also continued during the week, typically at rates of ten=s per day.
Read allWed, 16 Apr 2003, 06:00
Miyake-jima has remained restless since its summer eruption in 2000, with robust degassing ongoing through the week of 16-22 April. The SO2 gas output (flux) remained high (about 5,000-10,000 tons/day) as of March 2003. All people who lived on Miyake-jima island have been evacuated since September 2000 and SO2 fluxes around that time had reached extremely high values, over 80,000 tons/day.
Read allWed, 16 Apr 2003, 06:00
Llaima remained at Yellow alert at least through 16 April and eruptions began to contain significant tephra. Seismicity was almost 5-fold above background. Volcanologists expressed concern that the volcano=s glacial ice-cover could undergo local melting, which might lead to large and sudden outbursts of water (glacier bursts) down local drainages.
Read allWed, 16 Apr 2003, 06:00
A moderate vulcanian eruption of Kliuchevskoi began 15 April; it continued through at least 16 April. The eruption was preceded by above-background seismicity, and on 15 April there were ~70 earthquakes per day at ~30-km depth. Instruments registered continuous spasmodic volcanic tremor (up to 4.0 µm/second) and numerous weak shallow earthquakes.
Read allWed, 16 Apr 2003, 06:00
During the week ending 22 April, Kilauea continued to erupt, sending lava down its SE flank either traveling over the land surface or through tubes. Lava entered the sea at the West Highcastle entry; activity there was sometimes weak, though one or more glowing areas were typically seen.
Read allWed, 16 Apr 2003, 06:00
Karymsky's eruptive vigor increased. Although seismicity stood at background levels during the past week and slightly above background levels on 14 April, ten=s of volcanic earthquakes per day began to be registered. Observations made on 16 April suggested the presence of fresh ash deposits extending to the ESE for a distance of over 10 km from the summit.
Read allWed, 16 Apr 2003, 06:00
Karangetang's S crater gave off ash emissions that reached 250 m high during the week of 16-22 April. Just prior, on 15 April, an explosion that sounded like a blast was followed by lava avalanches traveling S and W and reaching ~1 km from their source at S crater. The resulting dark-gray ash column reached 1.5 km above the crater.
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