Active volcanoes in the world: August 21 – August 27, 2013

During past seven days 5 volcanoes had new activity, ongoing activity was reported for 12 volcanoes. This report covers active volcanoes in the world from August 21 – August 27, 2013 based on Smithsonian/USGS criteria.

New activity/unrest: | Ebulobo, Lesser Sunda Islands (Indonesia) | Ijen, Eastern Java (Indonesia) | Kliuchevskoi, Central Kamchatka (Russia) | Santa María, Guatemala | Suwanose-jima, Ryukyu Islands and Kyushu

Ongoing activity: | Fuego, Guatemala | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Kizimen, Eastern Kamchatka (Russia) | Manam, Northeast of New Guinea (SW Pacific) | Pacaya, Guatemala | Rabaul, New Britain | Sakura-jima, Kyushu | Shiveluch, Central Kamchatka (Russia) | Tolbachik, Central Kamchatka (Russia) | Veniaminof, Alaska Peninsula | White Island, New Zealand

The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the US Geological Survey's Volcano Hazards Program. Updated by 2300 UTC every Wednesday, notices of volcanic activity posted on these pages are preliminary and subject to change as events are studied in more detail. This is not a comprehensive list of all of Earth's volcanoes erupting during the week, but rather a summary of activity at volcanoes that meet criteria discussed in detail in the "Criteria and Disclaimers" section. Carefully reviewed, detailed reports on various volcanoes are published monthly in the Bulletin of the Global Volcanism Network.

New activity

EBULOBO, Lesser Sunda Islands (Indonesia) 
8.82°S, 121.18°E; summit elev. 2124 m

CVGHM reported that observers at Ebulobo's observation post in Ekowolo (Boa Wae District) noted that during August white plumes rose as high as 30 m. Volcanic tremor was detected starting on 10 August. At night during 21-23 August incandescence was visible on the N side of the summit (incandescence was last observed in 2011). The Alert Level was raised to 2 (on a scale of 0-4) on 23 August. Residents and tourists were not permitted within a 1.5-km-radius of the crater.

Geologic summary: Ebulobo, also referred to as Amburombu or Keo Peak, is a symmetrical stratovolcano in central Flores Island. The summit of 2124-m-high Gunung Ebulobo cosists of a flat-topped lava dome. The 250-m-wide summit crater of the steep-sided volcano is breached on three sides. The Watu Keli lava flow traveled from the northern breach to 4 km from the summit in 1830, the first of only four recorded historical eruptions of the volcano.

IJEN, Eastern Java (Indonesia) 
8.058°S, 114.242°E; summit elev. 2799 m

CVGHM reported that during 1 July-25 August diffuse white plumes rose 100-150 m above Ijen's crater, the lake water was light green, and seismicity decreased. On 26 August the Alert Level was lowered to 2 (on a scale of 1-4). Visitors, tourists, miners, and hikers were reminded not to approach the crater within 1 km.

Geologic summary: The Ijen volcano complex at the eastern end of Java consists of a group of small stratovolcanoes constructed within the large 20-km-wide Ijen (Kendeng) caldera. The north caldera wall forms a prominent arcuate ridge, but elsewhere the caldera rim is buried by post-caldera volcanoes, including Gunung Merapi stratovolcano, which forms the 2799 m high point of the Ijen complex. Immediately west of Gunung Merapi is the renowned historically active Kawah Ijen volcano, which contains a nearly 1-km-wide, turquoise-colored, acid crater lake. Picturesque Kawah Ijen is the world's largest highly acidic lake and is the site of a labor-intensive sulfur mining operation in which sulfur-laden baskets are hand-carried from the crater floor. Many other post-caldera cones and craters are located within the caldera or along its rim. The largest concentration of post-caldera cones forms an E-W-trending zone across the southern side of the caldera. Coffee plantations cover much of the Ijen caldera floor, and tourists are drawn to its waterfalls, hot springs, and dramatic volcanic scenery.

KLIUCHEVSKOI, Central Kamchatka (Russia) 
56.057°N, 160.638°E; summit elev. 4850 m

KVERT reported that moderate seismic activity at Kliuchevskoi was detected during 16-23 August. A video camera recorded incandescence from the summit at night, and gas-and-steam plumes containing minor amounts of ash rising to an altitude of 5.5 km (18,000 ft) a.s.l. A thermal anomaly from the lava dome was detected in satellite images during 16-18 and 20-23 August; cloud cover obscured views on 19 August. The Aviation Color Code remained at Yellow.

Geologic summary: Kliuchevskoi is Kamchatka's highest and most active volcano. Since its origin about 6000 years ago, the beautifully symmetrical, 4835-m-high basaltic stratovolcano has produced frequent moderate-volume explosive and effusive eruptions without major periods of inactivity. Kliuchevskoi rises above a saddle NE of sharp-peaked Kamen volcano and lies SE of the broad Ushkovsky massif. More than 100 flank eruptions have occurred at Kliuchevskoi during the past roughly 3000 years, with most lateral craters and cones occurring along radial fissures between the unconfined NE-to-SE flanks of the conical volcano between 500 m and 3600 m elevation. The morphology of its 700-m-wide summit crater has been frequently modified by historical eruptions, which have been recorded since the late-17th century. Historical eruptions have originated primarily from the summit crater, but have also included numerous major explosive and effusive eruptions from flank craters.

SANTA MARIA, Guatemala 
14.756°N, 91.552°W; summit elev. 3772 m

INSIVUMEH reported constant lava extrusion from Santa María's Santiaguito lava-dome complex on 22 August. At 1745 a series of collapses of the SE crater rim generated pyroclastic flows that reached the S and SE base of the complex. Bombs were ejected 500 m SW and ash plumes rose 4 km. A weak explosion on 23 August generated a white plume that rose 600 m. Ashfall was reported in the Palajunoj region (S).

At 0815 on 24 August a partial collapse of the SE crater rim of Caliente cone was accompanied by an explosion heard 20 km away and a shock wave. The explosion also rattled homes within 10 km. The collapse was followed by pyroclastic flows, avalanches, and more explosions. At 2210 another similar collapse occurred, producing a blast heard 15 km away and pyroclastic flows that descended the SE flank. Houses within 10 km again vibrated. Ash plumes rose as high as 4 km and drifted W and SW. On 25 August explosions continued and block avalanches descended the E flank of Caliente cone. At 0324 on 27 August a moderate explosion produced a mushroom-shaped ash plume that rose 1.3 km, and drifted SW, causing ashfall in Palajunoj. A pyroclastic flow traveled SW, and avalanches traveled S and E. White gas plumes rose 1.2 km.

Geologic summary: Symmetrical, forest-covered Santa María volcano is one of a chain of large stratovolcanoes that rises dramatically above the Pacific coastal plain of Guatemala. The stratovolcano has a sharp-topped, conical profile that is cut on the SW flank by a large, 1-km-wide crater, which formed during a catastrophic eruption in 1902 and extends from just below the summit to the lower flank. The renowned Plinian eruption of 1902 followed a long repose period and devastated much of SW Guatemala. The large dacitic Santiaguito lava-dome complex has been growing at the base of the 1902 crater since 1922. Compound dome growth at Santiaguito has occurred episodically from four westward-younging vents, accompanied by almost continuous minor explosions and periodic lava extrusion, larger explosions, pyroclastic flows, and lahars.

SUWANOSE-JIMA, Kyushu
29.635°N, 129.716°E; summit elev. 799 m

According to the Tokyo VAAC, the JMA reported explosions from Suwanose-jima during 26-27 August. Plumes rose to an altitude of 1.2 km (4,000 ft) a.s.l. on 27 August, and drifted NE and SE.

Geologic summary: The 8-km-long, spindle-shaped island of Suwanose-jima in the northern Ryukyu Islands consists of an andesitic stratovolcano with two historically active summit craters. Only about 50 persons live on the sparsely populated island. The summit of the volcano is truncated by a large breached crater extending to the sea on the east flank that was formed by edifice collapse. Suwanose-jima, one of Japan's most frequently active volcanoes, was in a state of intermittent strombolian activity from On-take (Otake), the NE summit crater, that began in 1949 and lasted until 1996, after which periods of inactivity lengthened. The largest historical eruption took place in 1813-14, when thick scoria deposits blanketed residential areas, and the SW crater produced two lava flows that reached the western coast. At the end of the eruption the summit of On-take collapsed forming a large debris avalanche and creating the horseshoe-shaped Sakuchi caldera, which extends to the eastern coast. The island remained uninhabited for about 70 years after the 1813-1814 eruption. Lava flows reached the eastern coast of the island in 1884.

Ongoing activity

FUEGO, Guatemala 
14.473°N, 90.880°W; summit elev. 3763 m

INSIVUMEH reported that during 22 and 24-25 August explosions from Fuego generated ash plumes that rose 300-500 m and drifted W and NW. Degassing and rumbling sounds were also reported. Active lava flows were 300 and 500 m long in the Taniluyá (SW) and Ceniza (SSW) drainages, respectively. On 23 August lava extrusion increased. Ash plumes rose about 1 km and drifted 12 km W.  Fourteen explosions during 26-27 August produced ash plumes that rose 200-500 m and drifted 8 km. Incandescent material was ejected 150 m high, and avalanches from the crater descended the flanks. 

Geologic summary: Volcán Fuego, one of Central America's most active volcanoes, is one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta, lies between 3,763-m-high Fuego and its twin volcano to the N, Acatenango. Construction of Meseta volcano continued until the late Pleistocene or early Holocene, after which growth of the modern Fuego volcano continued the southward migration of volcanism that began at Acatenango. Frequent vigorous historical eruptions have been recorded at Fuego since the onset of the Spanish era in 1524, and have produced major ashfalls, along with occasional pyroclastic flows and lava flows. The last major explosive eruption from Fuego took place in 1974, producing spectacular pyroclastic flows visible from Antigua.

KARYMSKY, Eastern Kamchatka (Russia) 
54.05°N, 159.45°E; summit elev. 1536 m

KVERT reported that moderate seismic activity at Karymsky was detected during 16-23 August. Based on seismic interpretation by Kamchatka Branch of Geophysical Services (KBGS; Russian Academy of Sciences), possible ash plumes rose to an altitude of 4 km (13,100 ft) a.s.l. on 19 August and to an altitude of 2 km (6,600 ft) a.s.l. the other days of the week. Satellite imagery showed a weak thermal anomaly on the volcano on 17, 20, and 22 August. On 22 August a pilot observed an ash plume near the volcano; that same day an ash plume was visible in satellite images drifting 30 km ESE at altitudes of 1-1.5 km (3,300-4,900 ft) a.s.l. The Aviation Color Code remained at Orange.

Geologic summary: Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed about 7,600-7,700 radiocarbon years ago. Construction of the Karymsky stratovolcano began about 2,000 years later. The latest eruptive period began about 500 years ago, following a 2,300-year quiescence. Much of the cone is mantled by lava flows less than 200 years old. Historical eruptions have been Vulcanian or Vulcanian-Strombolian with moderate explosive activity and occasional lava flows from the summit crater. Most seismicity preceding Karymsky eruptions has originated beneath Akademia Nauk caldera, which is located immediately S of Karymsky volcano and erupted simultaneously with Karymsky in 1996.

KILAUEA, Hawaii (USA) 
19.421°N, 155.287°W; summit elev. 1222 m

During 21-27 August HVO reported that the circulating lava lake occasionally rose and fell in the deep pit within Kilauea's Halema'uma'u Crater; the lake level was 35-39 m below the crater floor on most days. The plume from the vent continued to deposit variable amounts of ash, spatter, and Pele's hair onto nearby areas.

At Pu'u 'O'o Crater, glow emanated from spatter cones on the N and S portions of the crater floor. The Kahauale’a 2 lava flow, fed by the NE spatter cone, was active with scattered break-out flows and burned the forest N of Pu'u 'O'o. During 22 and 26-27 August two lava flows from the NE spatter cone were visible, and HVO noted that lava from the NW spatter cone had built a second, taller cone immediately to the E. Peace Day activity, fed by lava tubes extending from Pu'u 'O'o, consisted of some breakouts on the pali and coastal plain, and an ocean entry outside of the National Park boundary to the E which was last visible on 23 August.

Geologic summary: Kilauea, one of five coalescing volcanoes that comprise the island of Hawaii, is one of the world's most active volcanoes. Eruptions at Kilauea originate primarily from the summit caldera or along one of the lengthy E and SW rift zones that extend from the caldera to the sea. About 90% of the surface of Kilauea is formed of lava flows less than about 1,100 years old; 70% of the volcano's surface is younger than 600 years. A long-term eruption from the East rift zone that began in 1983 has produced lava flows covering more than 100 sq km, destroying nearly 200 houses and adding new coastline to the island.

KIZIMEN, Eastern Kamchatka (Russia) 
55.130°N, 160.32°E; summit elev. 2376 m

KVERT reported that during 16-23 August moderate seismic activity continued at Kizimen. Video and satellite data showed that lava continued to extrude from the summit, producing incandescence, strong gas-and-steam activity, and hot avalanches on the W and E flanks. A thermal anomaly was detected in satellite images during 16-18 and 20-23 August; cloud cover obscured views on 19 August. The Aviation Color Code remained at Orange.               

Geologic summary: Kizimen is an isolated, conical stratovolcano that is morphologically similar to Mount St. Helens prior to its 1980 eruption. The summit of Kizimen consists of overlapping lava domes, and blocky lava flows descend the flanks of the volcano, which is the westernmost of a volcanic chain north of Kronotsky volcano. The 2,376-m-high Kizimen was formed during four eruptive cycles beginning about 12,000 years ago and lasting 2,000-3,500 years. The largest eruptions took place about 10,000 and 8300-8400 years ago, and three periods of longterm lava-dome growth have occurred. The latest eruptive cycle began about 3,000 years ago with a large explosion and was followed by lava-dome growth lasting intermittently about 1,000 years. An explosive eruption about 1,100 years ago produced a lateral blast and created a 1.0 x 0.7 km wide crater breached to the NE, inside which a small lava dome (the fourth at Kizimen) has grown. A single explosive eruption, during 1927-28, has been recorded in historical time.

MANAM, Northeast of New Guinea (SW Pacific)
4.080°S, 145.037°E; summit elev. 1807 m

Based on observations of satellite imagery and wind data analyses, the Darwin VAAC reported that on 26 August ash plumes from Manam rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted almost 150 km NW.

Geologic summary: The 10-km-wide island of Manam, lying 13 km off the northern coast of mainland Papua New Guinea, is one of the country's most active volcanoes. Four large radial valleys extend from the unvegetated summit of the conical 1807-m-high basaltic-andesitic stratovolcano to its lower flanks. These "avalanche valleys," regularly spaced 90 degrees apart, channel lava flows and pyroclastic avalanches that have sometimes reached the coast. Two summit craters are present; both are active, although most historical eruptions have originated from the southern crater, concentrating eruptive products during much of the past century into the SE avalanche valley. Frequent historical eruptions, typically of mild-to-moderate scale, have been recorded at Manam since 1616. Occasional larger eruptions have produced pyroclastic flows and lava flows that reached flat-lying coastal areas and entered the sea, sometimes impacting populated areas.

PACAYA, Guatemala
14.381°N, 90.601°W; summit elev. 2552 m

INSIVUMEH reported that on 26 August Strombolian explosions from Pacaya's MacKenney Crater ejected incandescent material 50 m above the crater. Seismicity remained high. During 26-27 August explosions were detected at intervals between 10 seconds and 4 minutes. Incandescent material was ejected 75 m high. A lava flow 150-200 m long was active on the W flank.

Geologic summary: Eruptions from Pacaya, one of Guatemala's most active volcanoes, are frequently visible from Guatemala City, the nation's capital. Pacaya is a complex volcano constructed on the southern rim of the 14 x 16 km Pleistocene Amatitlan caldera. A cluster of dacitic lava domes occupies the caldera floor. The Pacaya massif includes the Cerro Grande lava dome and a younger volcano to the SW. Collapse of Pacaya volcano about 1,100 years ago produced a debris-avalanche deposit that extends 25 km onto the Pacific coastal plain and left an arcuate somma rim inside which the modern Pacaya volcano (MacKenney cone) grew. During the past several decades, activity at Pacaya has consisted of frequent Strombolian eruptions with intermittent lava flow extrusion on the flanks of MacKenney cone, punctuated by occasional larger explosive eruptions.

RABAUL, New Britain 
4.271°S, 152.203°E; summit elev. 688 m

Based on observations of satellite imagery and wind data analyses, the Darwin VAAC reported that on 25 August ash plumes from Rabaul caldera's Tavurvur cone rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted almost 150 km NW.

Geologic summary: The low-lying Rabaul caldera on the tip of the Gazelle Peninsula at the NE end of New Britain forms a broad sheltered harbor. The outer flanks of the 688-m-high asymmetrical pyroclastic shield volcano are formed by thick pyroclastic-flow deposits. The 8 x 14 km caldera is widely breached on the E, where its floor is flooded by Blanche Bay. Two major Holocene caldera-forming eruptions at Rabaul took place as recently as 3,500 and 1,400 years ago. Three small stratovolcanoes lie outside the northern and NE caldera rims. Post-caldera eruptions built basaltic-to-dacitic pyroclastic cones on the caldera floor near the NE and western caldera walls. Several of these, including Vulcan cone, which was formed during a large eruption in 1878, have produced major explosive activity during historical time. A powerful explosive eruption in 1994 occurred simultaneously from Vulcan and Tavurvur volcanoes and forced the temporary abandonment of Rabaul city.

SAKURA-JIMA, Kyushu 
31.585°N, 130.657°E; summit elev. 1117 m

Based on information from JMA, the Tokyo VAAC reported that during 21-27 August explosions from Sakura-jima generated plumes that rose to altitudes of 1.2-3.4 km (4,000-11,000 ft) a.s.l. and drifted in multiple directions. During 24 and 26-27 August pilots observed ash plumes that rose to altitudes of 2.4-3 km (8,000-10,000 ft) a.s.l. and traveled SE and E. JMA reported that six explosions from Showa Crater during 23-26 August ejected tephra as far as 1,300 m. Incandescence from the crater was visible during 25-26 August. 

Geologic summary: Sakura-jima, one of Japan's most active volcanoes, is a post-caldera cone of the Aira caldera at the northern half of Kagoshima Bay. Eruption of the voluminous Ito pyroclastic flow was associated with the formation of the 17 x 23-km-wide Aira caldera about 22,000 years ago. The construction of Sakura-jima began about 13,000 years ago and built an island that was finally joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kita-dake summit cone ended about 4,850 years ago, after which eruptions took place at Minami-dake. Frequent historical eruptions, recorded since the 8th century, have deposited ash on Kagoshima, one of Kyushu's largest cities, located across Kagoshima Bay only 8 km from the summit. The largest historical eruption took place during 1471-76.

SHIVELUCH, Central Kamchatka (Russia) 
56.653°N, 161.360°E; summit elev. 3283 m

Based on visual observations and analyses of satellite data, KVERT reported that during 16-23 August a viscous lava flow effused onto the N and NW flanks of Shiveluch's lava dome, accompanied by hot avalanches, incandescence, and fumarolic activity. Explosions generated ash plumes that rose to altitudes of 3.5-4.5 km (11,500-14,800 ft) a.s.l. and drifted E and NE. A thermal anomaly was detected in satellite images during 16-18 and 20-23 August; cloud cover obscured views on 19 August. On 27 August video images showed an ash plume rising 3.5-4 km (11,500-13,100 ft) a.sl. and drifting 30 km SE. The Aviation Color Code remained at Orange.

Geologic summary: The high, isolated massif of Shiveluch volcano (also spelled Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group and forms one of Kamchatka's largest and most active volcanoes. The currently active Molodoy Shiveluch lava-dome complex was constructed during the Holocene within a large breached caldera formed by collapse of the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large eruptions of Shiveluch have occurred during the Holocene, making it the most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent collapses of lava-dome complexes, most recently in 1964, have produced large debris avalanches whose deposits cover much of the floor of the breached caldera. Intermittent explosive eruptions began in the 1990s from a new lava dome that began growing in 1980. The largest historical eruptions from Shiveluch occurred in 1854 and 1964.

TOLBACHIK, Central Kamchatka (Russia) 
55.830°N, 160.330°E; summit elev. 3682 m

KVERT reported that the S fissure along the W side of Tolbachinsky Dol, a lava plateau on the SW side of Tolbachik, continued to produce very fluid lava flows during 16-22 August that traveled to the W, S, and E sides of the plateau. Cinder cones continued to grow along the S fissure and weak gas-and-steam plumes were observed. A thermal anomaly on the N part of Tolbachinsky Dol was visible daily in satellite imagery.

Seismic activity decreased during 22-24 August. Video images showed no incandescence from the N part of Tolbachinsky Dol, although a thermal anomaly continued to be detected in satellite images. On 27 August the Aviation Color Code was lowered to Yellow.

Geologic summary: The massive Tolbachik basaltic volcano is located at the southern end of the dominantly andesitic Kliuchevskaya volcano group. The Tolbachik massif is composed of two overlapping, but morphologically dissimilar volcanoes. The flat-topped Plosky Tolbachik shield volcano with its nested Holocene Hawaiian-type calderas up to 3 km in diameter is located east of the older and higher sharp-topped Ostry Tolbachik stratovolcano. The summit caldera at Plosky Tolbachik was formed in association with major lava effusion about 6500 years ago and simultaneously with a major southward-directed sector collapse of Ostry Tolbachik volcano. Lengthy rift zones extending NE and SSW of the volcano have erupted voluminous basaltic lava flows during the Holocene, with activity during the past two thousand years being confined to the narrow axial zone of the rifts. The 1975-76 eruption originating from the SSW-flank fissure system and the summit was the largest historical basaltic eruption in Kamchatka.

VENIAMINOF, Alaska Peninsula 
56.17°N, 159.38°W; summit elev. 2507 m

AVO reported that on 20 August residents of Perryville (32 km SSE) reported hearing loud explosions coming from Veniaminof, and air waves were detected by infrasound equipment in Dillingham (322 km NE). Trace amounts of ash fell in Perryville. During 20-21 August seismic activity at Veniaminof decreased; seismicity became more episodic and fluctuated between periods of relative quiet and short periods of low-level, nearly continuous tremor. Minor ash-and-steam emissions likely continued, but effusion of lava may have slowed down or possibly stopped. Elevated surface temperatures at the cone were observed in satellite data.

Seismicity during 22-26 August remained low; small ash bursts were probably produced during short periods of elevated tremor. During 23-26 August satellite data showed weak thermal anomalies at the intracaldera cone and very minor ash emissions were occasionally observed in web camera views from Perryville. During 26-27 August seismicity was characterized by nearly continuous, gradually fluctuating tremor possibly indicative of low-level ash emission and probable lava effusion. Satellite images detected a thermal signal at the intracaldera cone. Web camera views from Perryville showed a slightly more robust ash plume, extending ESE beyond the caldera rim. The Volcano Alert Level remained at Watch and the Aviation Color code remained at Orange.

Geologic summary: Massive Veniaminof volcano, one of the highest and largest volcanoes on the Alaska Peninsula, is truncated by a steep-walled, 8 x 11 km, glacier-filled caldera that formed around 3,700 years ago. The caldera rim is up to 520 m high on the N, is deeply notched on the W by Cone Glacier, and is covered by an ice sheet on the S. Post-caldera vents are located along a NW-SE zone bisecting the caldera that extends 55 km from near the Bering Sea coast, across the caldera, and down the Pacific flank. Historical eruptions probably all originated from the westernmost and most prominent of two intra-caldera cones, which reaches an elevation of 2,156 m and rises about 300 m above the surrounding icefield. The other cone is larger, and has a summit crater or caldera that may reach 2.5 km in diameter, but is more subdued and barely rises above the glacier surface.

WHITE ISLAND, New Zealand 
37.52°S, 177.18°E; summit elev. 321 m

The GeoNet Data Centre reported that after the eruption at White Island on 20 August, activity remained low through the next day. Steam-and-gas plumes continued to be emitted. During the afternoon on 21 August the Volcanic Alert Level was lowered to 1 and the Aviation Colour Code was lowered to Yellow.

Geologic summary: The uninhabited 2 x 2.4 km White Island, one of New Zealand's most active volcanoes, is the emergent summit of a 16 x 18 km submarine volcano in the Bay of Plenty about 50 km offshore of North Island. The 321-m-high island consists of two overlapping stratovolcanoes; the summit crater appears to be breached to the SE because the shoreline corresponds to the level of several notches in the SE crater wall. Throughout the short historical period beginning in 1826 the volcano has had long periods of continuous hydrothermal activity and steam release, punctuated by small-to-medium eruptions. Its activity also forms a prominent part of Maori legends. The most recent eruptive episode, which began on 7 March 2000, included the largest eruption at White Island in the past 20 years on 27 July.

Source: GVP