CENAPRED reported that low-intensity exhalations occurred during most of the week. At 1118 on 30 December an intense seismic signal was recorded for 4 minutes that was characteristic of exhalations with explosive initial phases. At 1955 on 30 December a pilot report stated that an eruption sent an ash cloud to 8.5 km a.s.l.
Surface lava flows continued to travel down Pulama Pali and across the coastal flat to within about 2 km inland from the sea. Overall, seismic tremor was weak-to-moderate near Pu`u `O`o and was weak beneath Kilauea caldera. The tiltmeters at Kilauea's summit and along the east rift zone showed flat signals.
Because seismic activity was at background levels throughout the week KVERT reduced the Concern Color Code from Yellow to Green.
The IG reported that in comparison to November the number of long-period earthquakes, which has been shown at Guagua Pichincha to reflect the amount of lava dome growth, and the number of rockfalls decreased in December. Activity has remained relatively constant, with a daily average of 514 earthquakes.
The IG reported that on 21 December an ash cloud was observed over the summit of Tungurahua at a height of ~5.8 km a.s.l. According to the Washington VAAC, the ash was not visible on GOES-8 imagery.
The VSI reported that during 12-18 December explosion and tremor activity at the volcano increased in comparison to the previous week. Minor explosions sent ash to 500-600 m above the crater rim. In addition, continuous tremor and a large number of explosion earthquakes (2,375) were recorded.
The Washington VAAC reported that throughout the week low-level (up to ~2 km) ash clouds that were produced by rockfalls, and periodic hot spot activity were visible on GOES-8 imagery.
KVERT reported that much like the previous week, the character of the volcanic activity did not change during 15-22 December. On 15 and 20 December weak seismicity was registered at the volcano and at 2105 on 15 December a seismic event was likely accompanied by a gas-and-ash explosion that sent a cloud to an inferred height of 2 km a.s.l. On 20 December a gas-and-steam plume rose 200-300 m above the crater.
Wed, 20 Dec 2000, 06:00
Volcanic activity at Popocatépetl decreased in comparison to last week. The Washington VAAC reported that during 21 to 25 December there were intermittent emissions of mostly steam. In addition, several small-to-moderate explosive events occurred during the week; at 1555 on 24 December ash was erupted to ~9 km a.s.l. and then blown to the E; at 1045 on 25 December ash was erupted to between 5.5 and 7.6 km a.s.l., blown to the NE, and deposited less than 5 km from the summit; and moderate exhalations occurred at 0111 and 0631 on 27 December that sent ash up to 7.6 and 9.8 km, respectively.
Read allWed, 20 Dec 2000, 06:00
During the week surface lava flows continued to flow down Pulama pali, with the lava flow front more than 2 km inland from the sea. Overall, seismic tremor was weak to moderate near Pu`u `O`o and was weak beneath Kilauea caldera. The tiltmeters at Kilauea's summit and along the east rift zone showed flat signals.
Read allWed, 20 Dec 2000, 06:00
KVERT reported that seismic activity was at background levels at Karymsky until 0905 to 0915 on 20 December when shallow earthquakes registered under the volcano were accompanied by short-lived explosions. At 2150 the same day, a pilot confirmed the presence of ash at the summit of the volcano and mud traces from melting snow on the edifice slopes. On 21 and 22 December (the end of KVERT's report period) seismicity was above background levels.
Read allWed, 20 Dec 2000, 06:00
The VSI reported that during 12-18 December, activity increased at Karangetang in comparison to the previous week. A thin plume continued to be emitted from the main crater and Crater II, but it rose higher than last week: up to 150 m above the summit. A "red flame," possibly indicating illumination of the plume by lava fountaining or incandescent material at the summit, was observed rising up to 75 m above the summit.
Read allWed, 20 Dec 2000, 06:00
Volcanic activity at Etna was low during December, with low gas emission at the SE Crater throughout the month and a few isolated Strombolian events at the Bocca Nuova crater in mid-December.
Read allWed, 13 Dec 2000, 06:00
The IG reported that at 1415 on 14 December an ash cloud was observed at an altitude of ~5.5 km a.s.l. near Tungurahua's summit, moving to the NE. No ash was visible in GOES 8 imagery.
Read allWed, 13 Dec 2000, 06:00
The VSI reported that during 5-11 December volcanic activity at Bromo cone in the Tengger caldera was marked by ongoing explosions and continuous tremor. Ash clouds produced from the explosions reached 150-900 m above the crater rim. The volcano remained at Alert Level 2 (ranging from 1 to 4).
Read allWed, 13 Dec 2000, 06:00
Activity at the Soufrière Hills volcano remained at an elevated level during 8-15 December, with continued growth of the lava dome. Seismic activity was comparable to last week and the main focus of volcanic activity remained on the E flank. Near-continuous rockfalls and ash venting occurred from the summit area, producing ash clouds that traveled to the W of the volcano.
Read allWed, 13 Dec 2000, 06:00
KVERT reported that the character of volcanic activity at Shiveluch did not change during 9-16 December. Weak seismicity was registered at the volcano during most of the week. Much like the previous week, two seismic events occurred that were above normal levels.
Read allWed, 13 Dec 2000, 06:00
The VSI reported that during 5-11 December fume from Jonggring Seloko crater located in the S sector of Semeru's summit rose up to 600 m above the crater. The seismic record was dominated by explosion earthquakes and the record showed that two pyroclastic flows occurred. The volcano remained at Alert Level 2 (ranging from 1 to 4).
Read allWed, 13 Dec 2000, 06:00
For the first time in 6 years, continuous-fountaining Strombolian-style eruptions of incandescent spatter occurred at Popocatépetl, marking a significant change in eruption behavior. In addition, strong harmonic tremor and high-mass flux rates have occurred. As of the end of the report period, the summit crater contained hot lava, and continuous ash emissions deposited ash in several towns surrounding the volcano.
Read allWed, 13 Dec 2000, 06:00
Lava flowed into the sea at the Kamokuna entry until 17 December. From the 17th until the 19th of December (the end of the report period) no lava was observed flowing into the sea. During the week several `a`a flows were visible traveling down Pulama pali.
Read allWed, 13 Dec 2000, 06:00
The VSI reported that during 5-11 December activity increased at Karangetang in comparison to previous weeks. Seismic activity was high, with an extreme increase in volcanic earthquakes. A thin plume was emitted from the main crater and Crater II; the plume rose up to 50 m above the summit and a "fire plume" reached up to 25 m above the summit.
Read allWed, 13 Dec 2000, 06:00
The Guayaquil MWO reported to the Washington VAAC that an eruption occurred at 0148 on 15 December. No ash plume was visible in GOES-8 imagery and no further eruption details were reported. The IG reported that the high number of earthquakes that occurred during the week indicated that dome 9 continued to slowly grow.
Read allWed, 6 Dec 2000, 06:00
The IG reported an ash cloud at ~5 km a.s.l. (near-summit level) on 9 December. The Washington VAAC used GOES-8 imagery to confirm that the thin ash cloud was moving to the SW.
Read allWed, 6 Dec 2000, 06:00
According to reports from the VSI and aviation sources, a minor explosion took place on 8 December that sent ash to ~3 km a.s.l.
Read allWed, 6 Dec 2000, 06:00
The Washington VAAC reported that a small eruption at approximately 1645 on 9 December sent ash to ~ 4 km a.s.l. (near-summit level). The small ash cloud drifted to the W and NW, was initially dense, and rapidly dissipated so that it was no longer visible on satellite imagery by 2345.
Read allWed, 6 Dec 2000, 06:00
The MVO reported that during 1-8 December volcanism continued at an elevated level, with continued growth of the lava dome. Seismic activity was comparable to the previous week. The main focus of activity remained on the volcano's eastern flanks, although some small rockfalls were observed on the western side of the new growth.
Read allWed, 6 Dec 2000, 06:00
For most of the period during 1-8 December weak seismicity was registered at the volcano, however two seismic events occurred that were above normal levels. First, at 1853 on 6 December seismic data indicated that a gas-and-ash explosion may have occurred. The possible explosion was registered as a shallow seismic event and was followed by volcanic tremor.
Read allWed, 6 Dec 2000, 06:00
On 11 December an air report to the Darwin VAAC stated that volcanic ash was observed near Semeru at an altitude of ~7.6 km a.s.l. The Darwin VAAC stated that the activity may have been associated with Semeru, which frequently erupts ash to ~4.5 km. Due to cloudy conditions, any low-level volcanic activity that was occurring at that time was not visible in satellite imagery.
Read all
