St. Helens (Washington, USA)
Major eruption sends cloud to 23 km, destroys summit, and devastates region
Etna (Sicily, Italy)
Incandescent tephra ejected; temperature anomaly on S flank
Ruapehu (North Island, New Zealand)
Phreatic explosions end
White Island (New Zealand)
Explosions continue; new fumaroles and renewed inflation
Karkar (Offshore New Guinea, Papua New Guinea)
Weak eruptions through crater lake; inflation ends
Langila (New Britain Island, Papua New Guinea)
Eruption continues with tephra and small base surge; lava flow stops
Manam (Bismarck Sea, Papua New Guinea)
Ash emission and increased seismicity
Aso (Kyushu, Japan)
Activity declines
On-take (Honshu, Japan)
Emission of vapor and a little ash continues
Sakura-jima (Kyushu, Japan)
Largest number of explosions/month in five years
Kanlaon (Central Philippines)
Earthquake swarm
Krafla (Iceland)
Inflation continues; deflation event expected
OBITUARY
Death of David Johnston at St. Helens
St. Helens (Washington, USA)
12 June explosion, then lava dome extrusion
Krafla (Iceland)
Phreatic explosions as inflation slows
Villarrica (central Chile)
Ash ejection
Chirinkotan (Kurile Islands, Russia)
Lava flows and ash explosions
Karkar (Offshore New Guinea, Papua New Guinea)
Fumarolic activity continues
Langila (New Britain Island, Papua New Guinea)
Occasional explosions and glow
Manam (Bismarck Sea, Papua New Guinea)
Activity declines to ocasional ash emission
Ruapehu (North Island, New Zealand)
Activity declines
White Island (New Zealand)
New ash deposits, impact craters, and seismicity
Tengger Caldera (Java, Indonesia)
Large incandescent tephra to 1.5 km away
Bulusan (Luzon, Philippines)
Steam and ash emission
Kanlaon (Central Philippines)
Seismicity declines
On-take (Honshu, Japan)
Steaming continues
Sakura-jima (Kyushu, Japan)
Activity declines. Explosions/month tabulated since 1955
St. Helens (Washington, USA)
Explosions destroy lava dome; 18 May cloud detected over Europe and Asia
Hood (Oregon, USA)
Earthquake swarm
Krafla (Iceland)
Large fissure and eruption
Etna (Sicily, Italy)
Incandescent tephra ejection; decreased gravity readings
San Cristobal (Nicaragua)
Moderate vapor plume
Telica (Nicaragua)
Small steam plume emission continues
Cerro Negro (Nicaragua)
New fumarolic area on Cerro La Mula
Las Pilas (Nicaragua)
Minor fumarolic activity
Momotombo (Nicaragua)
Fumarole temperatures measured
Masaya (Nicaragua)
Large plume; high SO2 output
Akutan (Aleutian Islands, USA)
Steam and ash emission; recently-extruded lava flow
Makushin (Aleutian Islands, USA)
Recently-ejected tephra; vapor emission
Pavlof (Alaska, USA)
Steam and a little ash
Gorely (Kamchatka Peninsula, Russia)
Explosions and crater glow
Sakura-jima (Kyushu, Japan)
More frequent explosions
Suwanose-jima (Ryukyu Islands, Japan)
Tephra ejection
Usu (Hokkaido, Japan)
Cryptodome uplift and seismicity continue
Bulusan (Luzon, Philippines)
Ash eruption and earthquake swarm
Karkar (Offshore New Guinea, Papua New Guinea)
Possible ash emission
Langila (New Britain Island, Papua New Guinea)
Vulcanian explosions and glow
Manam (Bismarck Sea, Papua New Guinea)
Mild ash emission and occasional rumbling
St. Helens (Washington, USA)
One small explosion; lava dome growth stops
Hekla (Iceland)
Large tephra cloud and lava flows
Krafla (Iceland)
Inflation resumes after last month's eruption
Kilauea (Hawaii, USA)
Intrusion into the upper east rift zone
Etna (Sicily, Italy)
Two one-day eruptions
Gareloi (Aleutian Islands, USA)
Tephra cloud from summit crater
Arenal (Costa Rica)
Lava extrusion continues
Bulusan (Luzon, Philippines)
Explosions and seismicity continue
Malinao (Luzon, Philippines)
Small phreatic explosion
Mayon (Luzon, Philippines)
Harmonic tremor
Karkar (Offshore New Guinea, Papua New Guinea)
Gas emission strengthens
Langila (New Britain Island, Papua New Guinea)
Occasional tephra emission
Manam (Bismarck Sea, Papua New Guinea)
Ash emission continues
White Island (New Zealand)
Ash eruption
Gamalama (Halmahera, Indonesia)
Strong tephra eruption; 40,000 evacuate
Sakura-jima (Kyushu, Japan)
More frequent explosions
St. Helens (Washington, USA)
Harmonic tremor and vapor emission; 18 May material remains in upper atmosphere
Gareloi (Aleutian Islands, USA)
Renewed ash emission to six kilometers
Etna (Sicily, Italy)
Ashfall to coast; lava flow; bombs
Villarrica (central Chile)
Ash eruptions and pyroclastic flow
Bulusan (Luzon, Philippines)
Small ash ejection
Karkar (Offshore New Guinea, Papua New Guinea)
New fumarolic vents; seismicity intensifies
Langila (New Britain Island, Papua New Guinea)
More frequent incandescent activity
Manam (Bismarck Sea, Papua New Guinea)
Occasional ash emission
Krafla (Iceland)
Inflation nearing level that triggered earlier deflations
Ulawan (New Britain Island, Papua New Guinea)
Ash billows to 6 kilometers above crater
Karangetang (Sulawesi, Indonesia)
Cauliflower-shaped cloud; incandescent tephra
Gamalama (Halmahera, Indonesia)
Explosions from two craters; evacuees return
Krakatau (Indonesia)
Explosions continue
Semeru (Java, Indonesia)
Ash eruptions
Tengger Caldera (Java, Indonesia)
Explosions resume, then end
Aso (Kyushu, Japan)
Small ash emission
Asama (Honshu, Japan)
Seismicity increases
Kuchinoerabu-jima (Ryukyu Islands, Japan)
Weak ash emission
Sakura-jima (Kyushu, Japan)
Explosions continue
Atmospheric Effects
Atmospheric effects of probable volcanic origin
St. Helens (Washington, USA)
Explosive eruptions and new lava dome
Krafla (Iceland)
Fissure eruption
Ulawun (New Britain Island, Papua New Guinea)
Brief, intense explosive eruption
Langila (New Britain Island, Papua New Guinea)
Large explosions and block lava flow
Kilauea (Hawaii, USA)
Two intrusions into the upper east rift
Kavachi (Solomon Islands)
Small submarine eruption
Ruapehu (North Island, New Zealand)
Small ash eruption from crater lake
White Island (New Zealand)
Minor ash emission; deflation slows
St. Helens (Washington, USA)
Harmonic tremor and vapor emission; chemical data summarized
Pavlof (Alaska, USA)
Lava fountaining and ash emission; possible lava flow
Gareloi (Aleutian Islands, USA)
Aircraft samples stratospheric plume
Krafla (Iceland)
Eruption expected soon
Langila (New Britain Island, Papua New Guinea)
Eruption declines
Kavachi (Solomon Islands)
Submarine activity diminishes
Bulusan (Luzon, Philippines)
Seismic activity decreases
Mayon (Luzon, Philippines)
Occasional tremor episodes through November
Kanlaon (Central Philippines)
Seismicity still above normal in late November
Bayonnaise Rocks (Izu Islands, Japan)
Discolored water
Fukutoku-Okanoba (Volcano Islands, Japan)
Discolored water seen during April-July 1980
Minami-hiyoshi (Volcano Islands, Japan)
No observed activity since March 1978
Nikko (Volcano Islands, Japan)
No signs of activity since July 1979
Fukujin (Volcano Islands, Japan)
Water discoloration seen on 12 May 1980
Sakura-jima (Kyushu, Japan)
Lapilli and air shocks break windows
Asama (Honshu, Japan)
Frequent seismicity continues
St. Helens (Washington, USA)
Dome growth, vapor plumes, and earthquake swarms
Krafla (Iceland)
Four days of slow deflation, then inflation resumes
Sakura-jima (Kyushu, Japan)
Explosions continue; 1980 activity summarized
Kuchinoerabu-jima (Ryukyu Islands, Japan)
Seismicity and steaming decline; 28 September eruption fissure and tephra described
Bayonnaise Rocks (Izu Islands, Japan)
Discolored water seen on 23 December
Fukutoku-Okanoba (Volcano Islands, Japan)
Water discoloration observed in November and December 1980
Minami-hiyoshi (Volcano Islands, Japan)
No seawater discoloration seen in November-December 1980
Nikko (Volcano Islands, Japan)
No observation made
Fukujin (Volcano Islands, Japan)
No seawater discoloration seen in November-December 1980
Suwanose-jima (Ryukyu Islands, Japan)
December 1979-December 1980 explosions tabulated
Shikotsu (Hokkaido, Japan)
Seismicity increases
Mayon (Luzon, Philippines)
Steam emission, crater glow, and seismicity
Cerro Negro (Nicaragua)
Small vapor plume; seismicity drops
Cosigüina (Nicaragua)
No fumarolic activity visible
Las Pilas (Nicaragua)
Small vapor plume
Masaya (Nicaragua)
Continued emission of a large gas plume
Mombacho (Nicaragua)
Small intermittent plume
Momotombo (Nicaragua)
Summit crater fumaroles remain hot; night glow from crater
San Cristobal (Nicaragua)
Moderate vapor plume
Telica (Nicaragua)
Moderate vapor plume
Santa Ana (El Salvador)
Plume from inner crater fumaroles
San Miguel (El Salvador)
Small vapor plume
Pacaya (Guatemala)
Small cinder cone grows within MacKenney Crater
Santa Maria (western Guatemala)
Ash and gas eruptions eject blocks and tephra