Seismic activity was above background levels during 24-31 August. Weak shallow earthquakes within the volcano's edifice and signals that may have represented short-lived explosions were recorded. Thermal anomalies were visible on satellite imagery. The volcano remained at Concern Color Code Orange.
On 28 August very mild ash eruptions began. The eruptions followed an increase in the number and magnitude of low-frequency volcanic earthquakes a few days earlier. Eruptions continued until at least 31 August.
Volcanic activity remained relatively low at Popocatépetl, with small emissions of steam, gas, and minor amounts of ash.
Due to the threat of Pinatubo's crater lake overflowing during draining procedures, Philippine officials plan to evacuate ~40,000 residents of the town of Botolan 40 km NW of Pinatubo's crater to higher ground on 5 September. The crater lake is ~2.5 km wide, and contains ~210 million cubic meters of water. According to a Guardian news article, water in the crater rose to ~80 cm below the lowest point of the crater rim on 3 September.
During 13-26 August approximately 380 lava avalanches were observed travelling SW, extending a maximum distance of 2.8 km mainly down the Sat and Lamat rivers, and to a lesser extent towards the Senowo and Bebeng rivers. Seismic activity consisted primarily of avalanche earthquakes, as it had for the previous 2 weeks. The volcano remained at Alert Level 2 (on a scale of 1-4).
During the week seismicity was relatively low, SO2 emission rates were well above the baseline value of 500 metric tons per day, the edifice was slightly inflated, and steaming and incandescence were occasionally visible at the crater. The volcano remained at Alert Level 3.
On 18 August at 2230 an explosion produced an ash cloud that rose ~800 m above the crater and drifted over the town of Manado 25 km N of the volcano. Following the explosion there was a significant increase in volcanic earthquakes in comparison to the previous week. The volcano remained at Alert Level 2 (on a scale of 1-4).
Lava continued to enter the sea at the E Kupapa`u entry. Surface lava flows were visible on Pulama pali and the coastal flat. By 1 September a surface lava flow that broke out of the ocean-entry tube on the coastal plain during mid-August flowed across a County lava-viewing road.
Wed, 29 Aug 2001, 06:00
During 13-26 August eruptive activity ceased and seismic activity was dominated by small explosion earthquakes (2,252). The volcano remained at Alert Level 2 (on a scale of 1-4).
Read allWed, 29 Aug 2001, 06:00
During 13-26 August lava flowed ~1 km towards the Kehetang River, and ~1.6 km towards the Keting River. Avalanches that originated from the edges of the lava flows traveled up to 1.5 km. Seismicity was dominated by small explosion, avalanche, and multiphase earthquakes.
Read allWed, 22 Aug 2001, 06:00
On 9, 16, 17, and 21 August volcanic ballistic clasts were observed falling near the WSW edge of the crater. In addition, observations of the volcano on 22 August revealed that the lava lake had risen 40 m since 9 August.
Read allWed, 22 Aug 2001, 06:00
VSI stated that last week's report of volcanic activity at Makian on 16 August was false. An observer mistook the glow from a bush fire as volcanic activity.
Read allWed, 22 Aug 2001, 06:00
The Washington VAAC reported that nearly continuous ash emissions had occurred at Tungurahua since 6 August, but extensive cloudiness prohibited ash-cloud detection in satellite imagery. According to the Guayaquil MWO, a new eruption on 24 August at 1755 produced an ash cloud that rose to ~6 km and drifted E to SE. The same day IG reported that ash was emitted to 6-7.6 km.
Read allWed, 22 Aug 2001, 06:00
Volcanic activity at Soufrière Hills remained at a similar level as the previous week, except for an increase in hybrid seismic events. Rockfalls and pyroclastic flows observed in the upper reaches of the Tar River Valley appeared to originate from the new dome, which was obscured by meteorological clouds. After 22 August, banded tremor that had increased the previous week declined to low levels.
Read allWed, 22 Aug 2001, 06:00
Seismic activity was above background levels during the week. Spasmodic volcanic tremor and weak, shallow seismic signals (possible collapses and avalanches) were registered. Several small explosions produced gas-and-steam plumes that rose to a maximum height of 2 km above the dome.
Read allWed, 22 Aug 2001, 06:00
Volcanic activity remained relatively low at Popocatépetl, with small emissions of steam, gas, and minor amounts of ash.
Read allWed, 22 Aug 2001, 06:00
During 30 July-12 August lava avalanches traveled towards the SW, extending a maximum distance of 2.8 km down the Sat, Senowo, Lamat, and Bebeng Rivers. Seismic activity was dominated by avalanche earthquakes. The volcano remained at Alert Level 2 (on a scale of 1-4).
Read allWed, 22 Aug 2001, 06:00
Volcanic activity remained low at Mayon during 22-28 August. There was relatively little seismic activity, slight inflation, occasional observations of incandescence at the summit, and a moderate amount of steam emitted from the volcano. SO2 emission rates remained well above the baseline value of 500 metric tons per day.
Read allWed, 22 Aug 2001, 06:00
VSI reported that there was a significant decrease in seismic activity at Lokon during 30 July-12 August in comparison to during previous weeks. Small explosions at Tompaluan crater produced plumes that rose 25-250 m above the summit. The volcano remained at Alert Level 2 (on a scale of 1-4).
Read allWed, 22 Aug 2001, 06:00
Lava continued to flow down the Pulama pali, and into the ocean at the E Kupapa`u entry. On 25 August a small amount of sharp, short-lived inflation occurred at Pu`u `O`o cone and an hour later at Kilauea's summit. No change in volcanic or seismic activity accompanied the inflation.
Read allWed, 22 Aug 2001, 06:00
On 9 August a small explosion at Kerinci produced an ash cloud that rose 700 m above the summit. Workers in rice fields around the volcano heard a booming sound and VSI personnel saw the dark brown ash cloud drift to the NNE. During 30 July-12 August seismographs recorded 990 small explosion events.
Read allWed, 22 Aug 2001, 06:00
During 30 July-12 August seismic activity at Karangetang was dominated by explosion, avalanche, and multiphase earthquakes. A steam-and-ash plume rose to 600 m above the volcano. During 1-12 August lava flows and lava avalanches were rarely observed.
Read allWed, 22 Aug 2001, 06:00
Volcanic activity was relatively low at Etna during the week. Degassing and seismic activity continued at Etna's summit craters.
Read allWed, 15 Aug 2001, 06:00
Volcanic activity remained low during 10-17 August. Weak banded tremor began on 14 August and continued throughout the week. The new lava dome continued to grow within the scar produced from the 29 July partial dome collapse.
Read allWed, 15 Aug 2001, 06:00
The series of eruptions that began at Tungurahua on 6 August continued during the week. Seismic activity was characterized by many long-period earthquakes and seismic signals that represented ash emissions. Several sporadic explosions occurred, with the largest explosion beginning on 15 August at 2231.
Read allWed, 15 Aug 2001, 06:00
There was renewed volcanic and seismic activity at San Cristóbal during the week. During mid-August a gradual increase in seismic tremor and long-period earthquakes began and the amount of tremor peaked during the night of 11 August. The same night INETER personnel heard rumbling emanate from the volcano.
Read allWed, 15 Aug 2001, 06:00
An eruption began at Makian on 16 August at 1930. During the eruption, chunks of incandescent lava were ejected 75 m through the air. Residents were evacuated to the S side of the island. The volcano is at Alert Level Red.
Read allWed, 15 Aug 2001, 06:00
Seismic activity remained above background levels during the week and included several small earthquakes. On 15 August volcanic tremor decreased gradually to background levels. Observers in Klyuchi reported that on 11 August gas-and-steam plumes rose 1.2-1.5 km above the dome.
Read all