Volcanic and seismic activity were at low levels during 21-28 June at Soufrière Hills. Growth of the extruded lobe on the SE side of the lava dome appeared to have stagnated. The number of rockfalls decreased abruptly on the afternoon of 22 June, remained at low levels for the rest of the week, and declined to very low levels during the last 3 days of the report period.
Seismicity declined at Shiveluch during 21-28 June, but remained above background levels. It included earthquakes with magnitudes less than or equal to 1.9 at depths of 0-6 km, many local shallow seismic signals (from possible avalanches or weak gas-and-ash explosions), and episodes of weak intermittent volcanic tremor. Gas-and-steam plumes reached to 3 km above the lava dome and small avalanches were captured on video rolling down the dome on 23 June.
During 17-23 June, seismic and volcanic activity were higher than normal at Semeru. Lava avalanches were observed traveling 750 m E to the Besuk Kembar River. Seismicity included 670 explosion events. Semeru remained at Alert Level 2 (on a scale of 1-4).
During 26 June-1 July, there were small-to-moderate emissions of steam, gas, and ash at Popocatépetl. In addition, several episodes of low-amplitude harmonic tremor were recorded. The most notable emissions, on 26 June at 1110 and on 1 July at 0238, produced ash clouds to a height of ~2 km above the volcano.
During 17-23 June, observers noted 65 incandescent lava avalanches flowing predominately down Merapi's SW flank into the upstream portions of the Sat, Lamat, and Senowo rivers. The avalanches reached a maximum run-out distance of ~2.5 km. Seismicity decreased in comparison to the previous week.
During 25-30 June, surface lava flows were visible on Kilauea's SW flank. Mild deflation, totaling .9 microradians, occurred at Pu`u `O`o on 26 June around 2130. No other significant deformation was recorded during the report period.
During 21-28 June, seismicity was above background levels at Karymsky, with ~10 earthquakes occurring per hour. The character of seismicity suggested that weak ash-and-gas explosions and gas blow-outs had probably occurred. A steam-and-gas plume was visible on AVHRR satellite imagery on 25 June.
During 17-23 June, there was a significant increase in the number of shallow and deep volcanic earthquakes at Karangetang in comparison to the previous week. In addition, low-level plumes rose above the main crater and crater II. A red reflection was visible 25 m above the rim of crater II.
Wed, 19 Jun 2002, 06:00
During 19-23 June, volcanic and seismic activity were relatively low at Tungurahua. Activity consisted of emissions of gas, steam, and ash.
Read allWed, 19 Jun 2002, 06:00
The number of volcanic earthquakes at Asama began to increase on 22 June around 0100. JMA reported that a total of 210 earthquakes occurred during 0100-0800, with the number of B-type earthquakes peaking around 0300 and A-type earthquakes occurring during 0300-0700. In addition, the temperature of the crater floor had increased since May 2002.
Read allWed, 19 Jun 2002, 06:00
Volcanic activity at Soufrière Hills during 14-21 June was slightly higher than it had been the previous week. Rockfall activity increased abruptly on the night of 14 June and remained at moderately high levels until the 18th, when it declined. The active lobe on the SE side of the lava dome continued to grow and was topped by a small, low-angle spine extruded towards the SE.
Read allWed, 19 Jun 2002, 06:00
During 14-21 June, seismicity at Shiveluch remained above background levels and included earthquakes at depths of 0-6 km with magnitudes less than or equal to 2.4 on the 14th and less than or equal to 2 during the rest of the week. In addition, many local shallow seismic signals (from possible avalanches or weak gas-and-ash explosions) and episodes of weak intermittent volcanic tremor occurred. According to interpretations of seismic data, short-lived explosive eruptions on the 15th and 19th probably sent ash-and-gas plumes ~1 and 1.5 km above the lava dome, respectively.
Read allWed, 19 Jun 2002, 06:00
During 18-24 June, activity at Popocatépetl mainly consisted of small steam-and-gas emissions.
Read allWed, 19 Jun 2002, 06:00
During 10-16 June, incandescent lava avalanches flowed predominately down Merapi's SW flank to the upstream portions of the Sat, Lamat, and Senowo rivers to a maximum run-out distance of ~2.5 km. Seismicity decreased in comparison to the previous week. Merapi remained at Alert Level 2 (on a scale of 1-4).
Read allWed, 19 Jun 2002, 06:00
Shallow seismic activity declined during 14-21 June at Kliuchevskoi, but 10-15 earthquakes ~30 km beneath the volcano occurred daily, and weak spasmodic tremor continued to be registered during the week. By the end of the week, shallow seismic events occurred again. Low-level gas-and-steam clouds rose above the volcano on several days.
Read allWed, 19 Jun 2002, 06:00
Incandescent surface lava flows were sometimes visible at Kilauea during 19-24 June. Generally, seismicity was at background levels, except at Kilauea's crater where a swarm of long-period earthquakes that began on 5 June continued. In addition, moderate tremor occurred at Pu`u `O`o.
Read allWed, 19 Jun 2002, 06:00
During 14-21 June, seismicity was above background levels at Karymsky, with ~10 earthquakes occurring per hour. The character of seismicity suggested that weak ash-and-gas explosions and gas blow-outs had probably occurred. Thermal anomalies were visible on satellite imagery, but ash was not.
Read allWed, 19 Jun 2002, 06:00
During 17-23 June, ash continued to be emitted from Etna's Northeast Crater and to a lesser extent from Bocca Nuova crater. Ash plumes from Northeast Crater rose several hundred meters. Quiet degassing occurred at Voragine and Southeast craters. Seismicity was at low levels during the week.
Read allWed, 12 Jun 2002, 06:00
During 13-17 June, continuous degassing occurred at Tungurahua, accompanied by nearly continuous volcanic tremor, long-period earthquakes, and occasional small-to-moderate explosions sometimes preceded by volcano-tectonic events. On 13 June incandescence was visible in the crater, volcanic blocks rolled 500-800 m down Tungurahua's flanks, and continuous ash emissions were followed by three small explosions. A pilot reported observing a W-drifting steam-and-ash column ~2 km above the volcano's summit.
Read allWed, 12 Jun 2002, 06:00
Based on information from aircraft reports and JMA, the Tokyo VAAC stated that volcanic ash from Suwanose-jima was reported on 18 June at 1058 at a height of ~6 km drifting E. Ash was not visible on satellite imagery.
Read allWed, 12 Jun 2002, 06:00
On 9 June beginning at 2300 a swarm of volcano-tectonic earthquakes was recorded at Nevado del Ruiz. Next, hundreds of hybrid earthquakes were recorded, with more than 1,300 earthquakes occurring in 16 hours. High seismicity persisted for the following 3 days, with ~2,300 earthquakes recorded.
Read allWed, 12 Jun 2002, 06:00
Volcanic and seismic activity remained at low levels at Soufrière Hills during 7-14 June. The massive extrusive lobe on the SE side of the lava dome continued to grow steadily throughout the week, although there was a low level of rockfall and seismic activity. Minor rockfall activity occurred on the E flank of the dome, increasing slightly during the latter half of the week.
Read allWed, 12 Jun 2002, 06:00
During 7-14 June, seismicity at Shiveluch remained above background levels and included earthquakes with magnitudes less than or equal to 2.3 at depths of 0-6 km, many local shallow seismic signals (from possible avalanches or weak gas-and-ash explosions), and episodes of weak intermittent volcanic tremor. According to interpretations of seismic data, from one to three short-lived explosive eruptions per day probably sent ash-and-gas plumes ~1 km above the lava dome. Thermal anomalies were visible on AVHRR satellite imagery, but ash was not.
Read allWed, 12 Jun 2002, 06:00
During 12-18 June, activity at Popocatépetl mainly consisted of small steam-and-gas emissions. A photograph of the lava dome taken on 22 May revealed that it had diminished in size compared to 29 April. Based on information from ground reports, video footage, and MWO, the Washington VAAC reported that an eruption occurred on 17 June at 1140.
Read allWed, 12 Jun 2002, 06:00
The Washington VAAC reported that on 17 June at 0815 satellite imagery showed a very thin SW-drifting plume of unknown composition emitted from Pacaya. In addition, satellite imagery showed a faint hotspot at the volcano's summit.
Read allWed, 12 Jun 2002, 06:00
VSI reported that activity at Merapi was generally decreasing. During 3-9 June, incandescent lava avalanches flowed predominately down Merapi's SW flank to the upstream portions of the Sat, Lamat, and Senowo rivers to a maximum run-out distance of ~2.5 km. Merapi remained at Alert Level 2 (on a scale of 1-4).
Read allWed, 12 Jun 2002, 06:00
Seismic and volcanic activity at Lokon-Empung were above "normal" levels during 3-9 June, but there was a decline in seismicity in comparison to the previous week. The Alert Level at Lokon-Empung was reduced from 3 to 2 (on a scale of 1-4).
Read allWed, 12 Jun 2002, 06:00
Seismicity was above background levels at Kliuchevskoi during most of 7-14 June. On 11 June a ~30-minute-long series of earthquakes (ML less than or equal to 2.8) occurred in the volcano's edifice. Continuous spasmodic tremor continued to be recorded during the week and 22-48 earthquakes occurred per day ~30 km below the volcano.
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