Augustine

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  • Country
  • Subregion Name
  • Primary Volcano Type
  • Last Known Eruption
  • 59.363°N
  • 153.43°W

  • 1252 m
    4107 ft

  • 313010
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

19 September-25 September 2007

AVO increased the Volcanic Alert Level to Advisory and the Aviation Color Code to Yellow for Augustine on 22 September due to an increase in seismic activity below the summit over the previous week. During 22-25 September, the earthquakes were generally less than M 1 and were located at shallow depths beneath the summit.

Source: US Geological Survey Alaska Volcano Observatory (AVO)



 Available Weekly Reports


2007: September
2006: January | February | March | April | July | August
2005: November | December


19 September-25 September 2007

AVO increased the Volcanic Alert Level to Advisory and the Aviation Color Code to Yellow for Augustine on 22 September due to an increase in seismic activity below the summit over the previous week. During 22-25 September, the earthquakes were generally less than M 1 and were located at shallow depths beneath the summit.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


9 August-15 August 2006

AVO reduced the Concern Color Code at Augustine from Yellow to Green on 9 August. Seismic, satellite, and visual data indicated a decrease in activity to background levels. No changes were seen at the summit during the previous several months. AVO warned that the lava dome and surrounding area were still unstable despite the apparent cessation of lava-dome growth. Rockfalls and avalanches were still occurring, especially on the N flank, and may continue for several weeks or months.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


26 July-1 August 2006

According to the Anchorage VAAC, a pilot reported that on 27 July an ash plume from Augustine reached an altitude of 1.5 km (5,000 ft) a.s.l. and drifted SSE. The AVO did not find seismic evidence for this event, and seismicity levels remained low. They also stated that rockfalls and avalanches of hot debris from the cooling lava dome can produce small, localized ash plumes.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


26 April-2 May 2006

AVO reduced the Concern Color Code at Augustine from Orange to Yellow on 28 April. As of the 28th, instrumental and visual observations indicated that the growth of the summit lava dome and lava-flow emissions had stopped, or continued at very low rates. Seismic data showed that rockfalls and avalanches occurred at a diminished level. No changes were seen at the summit during the previous several weeks. AVO warned that despite the apparent cessation of lava-dome growth, the new dome and lava flows are still highly unstable, and rockfalls and avalanches are still occurring and may continue for several weeks or months.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


19 April-25 April 2006

Eruptive activity continued at Augustine during 14-21 April, with seismicity, rates of rockfall signals, and visual observations indicating continued lava effusion. On 17 and 18 April, a flurry of signals associated with avalanches occurred that were larger than those seen in the previous few weeks. Based on aerial observations on the 19th, it seemed that an active rockfall and avalanche chute had developed near the margin of the new lava flow/dome complex in the NW summit area. A blanket of ash related to recent rockfalls in this area was visible on the volcano's SW flank. Augustine remained at Concern Color Code Orange.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


12 April-18 April 2006

Activity at Augustine declined to low levels during 7-14 April, with seismicity decreasing to slightly above background levels, and rockfalls and avalanches decreasing in frequency in comparison to previous weeks. Low-level eruptive activity continued, consisting of slow effusion of lava at the summit accompanied by small rockfalls and avalanches on the volcano's flanks. Satellite imagery showed a decline in thermal output consistent with the decreased activity. Sulfur-dioxide gas measurements showed continued high levels of magmatic gas emissions that may have been associated with degassing of lava at the summit of the volcano. Augustine remained at Concern Color Code Orange.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


5 April-11 April 2006

Low-level eruptive activity continued at Augustine during 31 March to 4 April, although it was at lower levels than in previous weeks. The seismic network continued to record signals that were associated with occasional hot block-and-ash flows, rock avalanches, rockfalls, and lava flows. Small and dilute ash clouds resulting from these processes were likely confined to the immediate vicinity of the volcano. Satellite imagery continued to show a thermal anomaly at the volcano's summit. Airborne sulfur-dioxide gas measurements revealed continued magmatic gas emissions. Low-light camera observations indicated that activity was restricted mainly to the summit lava dome. Augustine remained at Concern Color Code Orange.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


29 March-4 April 2006

Low-level eruptive activity continued at Augustine during 24-31 March. Signals continued to be recorded by the seismic network that were associated with occasional hot block-and-ash flows, rock avalanches, rockfalls, and lava flows. Small and dilute ash clouds resulting from these processes were likely confined to the immediate vicinity of the volcano. Satellite imagery continued to show a thermal anomaly related to the new lava dome and lava flow. Airborne sulfur-dioxide gas measurements showed continued high levels of magmatic gas output. Low-light camera observations indicated that activity was restricted mainly to the summit lava dome. Augustine remained at Concern Color Code Orange.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


22 March-28 March 2006

Low-level eruptive activity continued at Augustine during 17-24 March. All available information indicated that the lava dome continued to grow, but the growth rate slowed in comparison to the previous week. Signals from small block-and-ash flows, rock avalanches, rockfalls, and lava flows continued to be recorded by the seismic network though at a decreased rate. Web-camera views showed continued steaming at the summit and occasional small rockfalls. Thermal anomalies continued to be visible on satellite imagery. Low-light camera images showed a decrease in thermal features in the volcano's summit area and on the upper NE flank compared to the previous week. Visual observations during 15-22 March revealed no large-scale dome growth. Decreased SO2 gas emission was measured on 22 March in comparison to 10 and 16 March. However, the level of SO2 emission was comparable to levels in late February and early March, and remained well above background. AVO reported that dome-building eruptive activity will likely continue, perhaps intermittently, over the next several weeks or months. Augustine remained at Concern Color Code Orange.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


15 March-21 March 2006

Low-level eruptive activity continued at Augustine during 10-17 March. The seismicity changed from periods of prolonged volcanic tremor and closely spaced discreet earthquakes to episodic short-duration events. This change indicated that steady effusion of lava and dome growth gave way to activity characterized by slower effusion of lava and intermittent block-and-ash-flows, rock avalanches, and rockfalls originating from the summit lava dome. Observers saw numerous hot avalanches and prolonged periods of incandescence in the summit area and on the upper NE flank on several evenings. Satellite images showed that thermal anomalies persisted. Observations made during overflights of the volcano indicated that two lava flows on the N and NE flanks continued to advance slowly. Occasional collapses of the lava-flow fronts shed hot blocks and produced minor ash emissions. Photographs indicated that the new lava dome was about 70 m higher than the level of the lava dome formed in 1986. Augustine remained at Concern Color Code Orange.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


8 March-14 March 2006

Low-level eruptive activity continued at Augustine during 3-10 March. The overall level of seismicity increased, with periods of prolonged volcanic tremor and an increase in the frequency of small volcano-tectonic earthquakes. The seismic network, particularly on the E flank, continued to record block-and-ash-flows, rock avalanches, and rockfalls that originated from the summit lava dome. Vigorous steaming was seen on 9 March, mostly from fumaroles on the S and W sides of the dome. Observations on 8 and 9 March revealed that small-scale collapses of the summit lava dome occurred regularly, usually producing block-and-ash-flows and small diffuse ash clouds. The block-and-ash-flows occurred on the E to NE sector of the volcano and extended to within ~1 km of the coastline. Airborne measurements of gas emissions on 9 March indicated both SO2 and CO2 gas in the plume. This was the first time since the fall of 2005 that CO2 had been a component of the gas plume, and likely indicated the presence of new magma entering the volcanic system. All available information indicated that the lava dome at the volcano's summit continued to grow. According to AVO, over several days before 10 March the rate of dome growth increased relative to the past several weeks, probably reflecting the influx of new magma. Augustine remained at Concern Color Code Orange.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


1 March-7 March 2006

Unrest continued at Augustine during 24 February to 3 March, with overall seismicity remaining low, but above background levels. Rockfalls and avalanches originating from the summit area continued to be recorded by the seismic network. Since inflation commenced on 10 February, a vertical change of 2-3 cm was measured by GPS (Global Positioning System). A thermal anomaly at the summit was visible on satellite and camera images, and incandescent avalanches were observed. All available information indicated that the lava dome continued to grow slowly. A plume composed of variable amounts of gas, steam, and small amounts of ash was emitted intermittently from the summit. Augustine remained at Concern Color Code Orange.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


22 February-28 February 2006

During 21-27 February, seismicity at Augustine was relatively low, but remained above background levels. Seismic data indicated that small rockfalls and avalanches from the lava dome occurred intermittently. A thermal anomaly was visible in the summit area on satellite and camera imagery. These data indicated that the lava dome at the volcano's summit continued to grow slowly. Observations during the report week revealed that a plume composed of variable amounts of gas, steam, and small amounts of ash was emitted intermittently from Augustine's summit. Augustine remained at Concern Color Code Orange.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


15 February-21 February 2006

During 15-19 February, AVO seismometers at Augustine recorded occasional rockfalls and small pyroclastic-flow signals indicative of minor collapses of the volcano's lava dome. During the previous week, the number of these events declined, suggesting that the rate of lava effusion may have slowed. Clear satellite views of the volcano on 16 February showed a thermal anomaly in the summit crater area. On the 19th, the web camera showed a light dusting of ash on the ENE flank of the volcano. AVO stated that during the report period a plume composed of variable amounts of gas, steam, and small amounts of ash was probably being emitted intermittently from Augustine's summit. They warned that occasional very localized ash clouds and light ashfall will be produced by collapses from the lava dome. Augustine remained at Concern Color Code Orange.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


8 February-14 February 2006

During 8-14 February, seismicity at Augustine remained at low levels, but was still above background. Also, low-level ash plumes and occasional pyroclastic flows occurred. Satellite and seismic data, and other remote observations indicated that a lava dome had been growing at the volcano's summit since 28 January. On the evening of 7 February, gas, ash, and incandescent blocks were observed descending the upper NE flank of Augustine. All available data indicated that as the lava dome grows, it periodically becomes unstable and small portions of it avalanche down the N flank, producing pyroclastic flows. The number of these flows gradually decreased during several days before 10 February, suggesting that the rate of lava extrusion also slowly declined. Data from continuous GPS receivers on the island indicated that the flanks of the volcano began to deflate around 28 January, marking a reversal in the swelling trend observed beginning in roughly June of 2005. AVO reported that based on all available data, eruptive activity associated with lava-dome building will continue over the next few days or weeks and may continue intermittently over the next several months. Augustine remained at Concern Color Code Orange.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


1 February-7 February 2006

During 1-7 February, occasional pyroclastic flows continued to travel down Augustine's flanks and low-level ash plumes reached no higher than 4.6 km (15,000 ft) a.s.l. on satellite imagery. On 3 February, seismicity decreased significantly, but remained above background levels. Seismicity remained low throughout the remainder of the report period. Satellite imagery from the evening of 6 February showed a persistent thermal signal and occasional light ash emission. On 7 February, a steam plume was visible rising ~150 m (~500 ft) above the summit. AVO warned that further explosive activity producing ash clouds to heights over 7.6 km (25,000 ft) may still occur with little or no warning. Augustine remained at Concern Color Code Orange.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC)


25 January-31 January 2006

After several days with no ash emissions and relatively low seismicity, Augustine erupted again on 27 January around 2001, with the most vigorous activity beginning around 2024. The eruption lasted about 9 minutes. AVO raised the Concern Color Code from Orange to Red, the highest level. According to the National Weather Service (NWS), the ash plume produced from the eruption reached ~12.2 km (40,000 ft) a.s.l. and drifted SE. An ashfall advisory was issued by the NWS. That same day, an eruption at 2337 lasted 1 minute and produced an ash plume below 3 km (10,000 ft) a.s.l. On 28 January at 0204 a 2-minute-long eruption began that sent ash to a height of 7.9 km (26,000 ft) a.s.l. and drifted SE. Later that day a 3-minute-long eruption began at 0742 that sent a NE-drifting ash plume to a height of 7.6 km (25,000 ft) a.s.l.

Augustine was in a state of continuous eruption from 1430 on 28 January through 31 January. The activity was characterized by steady ash emission and small pyroclastic flows. An observation flight on 29 January revealed diffuse drifting ash clouds at a height of ~7.6 km (25,000 ft) a.s.l. Also, ash-and-steam clouds rose from pyroclastic flows on the N flank of the volcano. Steam plumes rose from the NNE coastline, indicating that some of the pyroclastic flows had entered the sea. Satellite imagery on 31 January showed that plumes did not exceed 3.9 km (13,000 ft) a.s.l. and generally drifted N. According to a news article, Alaska Airlines cancelled flights to and from Anchorage on 30 and 31 January due to ash from Augustine in the airspace.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC), Aero-News.net


18 January-24 January 2006

Observations made during an overflight on 18 January indicated that the summit was steaming vigorously, consistent with the formation of a new lava dome. Observers also noted ballistic bombs, block and ash flow deposits, and dilute-cloud surge deposits on the volcano's flanks. A white ash-poor steam plume was observed rising to about 2.6 km (8,500 feet) a.s.l. Seismicity decreased significantly over 19-20 January, but remained above background levels through 24 January. Night-time satellite views during 22-24 January showed faint thermal anomalies.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


11 January-17 January 2006

Explosive activity began at Augustine on 11 January. The day before, AVO increased the Concern Color Code from Yellow to Orange when seismicity began to increase at the volcano. On 11 January at 0444 seismic signals began to be recorded that were interpreted as being associated with explosions at Augustine's summit. The Concern Color Code was increased to Red, the highest level. Another explosion occurred at 0513, and satellite imagery confirmed that an ash plume was produced that rose to ~9.1 km (30,000 ft) a.s.l. and drifted N and E. An ashfall advisory was issued by the National Weather Service. Seismicity decreased after the explosions. During a flight over the volcano, scientists saw volcanic mudflows on the E, S, and W sides of the volcano. Minor rock and snow avalanche deposits were visible high on the SW part of the edifice. According to news articles, several flights were canceled or diverted due to ash in air space.

On 12 January, the Concern Color Code was reduced to Orange. On 13 January, seismicity began to increase. An eruption on the 13th from about 0355 to 0439 produced an ash plume to 10.4 km (34,000 ft) a.s.l. On the 13th, the volcano entered a period of repetitive and explosive eruptions, with explosions occurring at 0444, 0847, 1122, and 1640. Each event produced ash plumes, mudflows, and pyroclastic flows. The ash plumes produced from these eruptions rose higher than 9.1 km (30,000 ft) a.s.l. Ash drifted ESE and a small amount of ash fell in communities of the SW Kenai Peninsula. Explosions on the 13th at 1858 and on the 14th at 0014 were similar in size and duration as the previous four. In response to these eruptions, the National Weather Service issued an ashfall advisory for the western Kenai Peninsula S of Ninilchik. No explosions were recorded later on the 14th. The level of seismic activity declined after an explosion on 14 January at 0016, so the Concern Color Code was reduced to Orange on 15 January at 0945. Observations on 16 January confirmed that pyroclastic deposits were widespread on the volcano's flanks, as seen in web camera images. Also, a small lava dome appeared to have extruded at the summit.

AVO reported on the 16th that the level of seismic activity at the volcano remained above background. It is likely, but not certain, that further explosive activity will occur. Explosive events similar to those of 13 and 14 January could occur with little or no warning.

Sources: US Geological Survey Alaska Volcano Observatory (AVO), Anchorage Volcanic Ash Advisory Center (VAAC), Los Angeles Times


4 January-10 January 2006

During 30 December to 6 January, seismicity at Augustine increased slightly in comparison to the previous week. In addition, vigorous steaming was visible from several summit fumaroles during clear weather late in the week. Varied fumarole temperatures were recorded during a thermal survey on 4 January, but there was no significant change in the distribution of thermal features since 22 December. A significant increase in the sulfur-dioxide flux was measured on 4 January, in comparison to values on 20 December. Augustine remained at Concern Color CodeYellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


28 December-3 January 2006

Unrest continued at Augustine during 23-30 December. Seismicity rates decreased during the week, while steam-and-gas emissions continued. Brief views of the volcano during clear weather revealed that steam was continuously emitted from the volcano. The activity continued to suggest that new magma is present beneath Augustine. Based on past eruptions at Augustine, AVO expects to see a sharp increase in earthquake activity prior to a significant explosive eruption. Augustine remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


21 December-27 December 2005

During 16-23 December, unrest continued at Augustine, with elevated seismicity and several small steam explosions occurring. Thermal imaging of the summit area on 22 December using a helicopter-mounted FLIR (Forward Looking Infrared Radiometer) confirmed the presence of a new, high-temperature fumarole or gas vent high on the S flank of the volcano. A gas-measurement flight on 20 December detected sulfur dioxide for the first time at Augustine since routine airborne measurements began in the early 1990s. Aerial observations and analysis of photography and video of the summit area indicated that some deformation occurred within the summit crater area. A crack or fissure was noted cutting the 1986 lava dome and extending to the SE. Heavy steam from this feature, along with patches of bare ground, indicated that heat output at the summit had increased. Augustine remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


14 December-20 December 2005

During 14-20 December, several small steam explosions occurred at Augustine and the smell of sulfur was reported by residents in a couple of villages E of the volcano. During an overflight on 12 December, AVO scientists saw profuse steaming from numerous fumaroles on the summit, emanating mainly from behind the 1986 lava dome. Several energetic fumaroles were also located ~200 m down the SE flank. A gas-and-steam plume extended ~74 km SE. Augustine remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


7 December-13 December 2005

Seismicity remained at elevated levels at Augustine during 30 November to 12 December. On 12 December a steam plume visible on video and satellite images extended 75 km SE of the volcano. During 9-12 December, changes in the style of earthquake activity at the volcano were recorded and there were reports of gas emissions and steaming. Seismic events on 9 and 11 December may have perturbed the hydrothermal system, initiating steam explosions. These events were consistent with reports of steaming at the summit observed on 10 December, and a distinct sulfur smell ("like from a sewer") in the air on the evening of 11 December at Nanwalek and Port Graham, approximately 80 km E of the volcano. Augustine remained at Concern Color Code Yellow.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


23 November-29 November 2005

On 29 November AVO raised the Concern Color Code at Augustine from Green to Yellow after recording long-term important changes in seismicity and ground deformation consistent with renewed volcanic unrest. There were no indications that an eruption was imminent or certain.

Beginning in May 2005, there was a slow increase in the number of earthquakes under Augustine. The earthquakes were generally small (less than M 1) and concentrated roughly 1 km below the volcano's summit. These earthquakes slowly increased from 4-8 earthquakes per day to 20-35 earthquakes per day. Additionally, data from a Global Positioning System (GPS) network on Augustine indicated that a slow, steady inflation of the volcano started in mid-summer 2005, continuing until the present. The GPS benchmark located nearest the summit moved a total of 2.5 cm. This motion is consistent with a source of inflation or pressure change centered under the volcano. This is the first such deformation detected at Augustine since measurements began just prior to the 1986 eruption. No reports of increased steaming were received by AVO, nor have satellite data shown increased thermal activity.

Source: US Geological Survey Alaska Volcano Observatory (AVO)


Summary of eruption dates and Volcanic Explosivity Indices (VEI).

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
2005 Dec 9 (?) 2006 Apr 27 (?) Confirmed 3 Historical Observations
1986 Mar 27 1986 Aug 31 Confirmed 4 Historical Observations
1976 Jan 22 (?) 1977 May 14 (?) Confirmed 4 Historical Observations
1971 Oct 7 1971 Oct 8 Confirmed 1 Historical Observations
1963 Oct 11 1964 Aug 19 Confirmed 2 Historical Observations
1935 Mar 13 1935 Aug 18 Confirmed 3 Historical Observations
1908 Unknown Confirmed 1 Historical Observations
[ 1902 ] [ Unknown ] Discredited    
1883 Oct 6 1884 (?) Confirmed 4 Historical Observations
1812 Unknown Confirmed 3 Historical Observations
1650 ± 100 years Unknown Confirmed   Tephrochronology
1540 ± 100 years Unknown Confirmed 4 Radiocarbon (corrected) Tephra layer B
1230 ± 50 years Unknown Confirmed   Radiocarbon (corrected) Tephra layer M
0930 ± 150 years Unknown Confirmed   Radiocarbon (corrected) Tephra layer C
0570 ± 150 years Unknown Confirmed   Radiocarbon (corrected) Tephra layer H
0340 ± 40 years Unknown Confirmed   Radiocarbon (corrected) Tephra layer I
0120 BCE ± 40 years Unknown Confirmed   Radiocarbon (corrected) Tephra layer G
0310 BCE ± 100 years Unknown Confirmed   Radiocarbon (corrected)
0350 BCE ± 200 years Unknown Confirmed   Tephrochronology
1820 BCE ± 300 years Unknown Confirmed   Radiocarbon (corrected)
2040 BCE ± 300 years Unknown Confirmed   Radiocarbon (corrected)
4150 BCE ± 100 years Unknown Confirmed   Radiocarbon (corrected)
5420 BCE ± 50 years Unknown Confirmed   Radiocarbon (corrected)

The following references are the sources used for data regarding this volcano. References are linked directly to our volcano data file. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title. Additional discussion of data sources can be found under Volcano Data Criteria.

Beget J E, Kienle J, 1992. Cyclic formation of debris avalanches at Mount St. Augustine volcano. Nature, 356: 701-704.

Beget J E, Kowalik Z, 2006. Confirmation and calibration of computer modeling of tsunamis produced by Augustine volcano, Alaska. Sci Tsunami Hazards, 24: 257-266.

Beget J, Gardner C, Davis K, 2008. Volcanic tsunamis and prehistorical cultural transitions in Cook Inlet, Alaska. J Volc Geotherm Res, 176: 377-386.

Henning R A, Rosenthal C H, Olds B, Reading E (eds), 1976. Alaska's volcanoes, northern link in the ring of fire. Alaska Geog, 4: 1-88.

IAVCEI, 1973-80. Post-Miocene Volcanoes of the World. IAVCEI Data Sheets, Rome: Internatl Assoc Volc Chemistry Earth's Interior..

Johnson K E, Harmon R S, Richardson J M, Moorbath S, Strong D F, 1996. Isotope and trace element geochemistry of Augustine volcano, Alaska: implications for magmatic evolution. J Petr, 37: 95-115.

Kamata H, Johnston D A, Waitt R B, 1991. Stratigraphy, chronology, and character of the 1976 pyroclastic eruption of Augustine volcano, Alaska. Bull Volc, 53: 407-419.

Kienle J, Kowalik Z, Murty T S, 1987. Tsunamis generated by eruptions from Mount St. Augustine volcano, Alaska. Science, 236: 1442-1447.

Kienle J, Swanson S E, 1980. Volcanic hazards from future eruptions of Augustine volcano, Alaska. Univ Alaska Geophys Inst, UAG R-275, 122 p.

Miller T P, McGimsey R G, Richter D H, Riehle J R, Nye C J, Yount M E, Dumoulin J A, 1998. Catalogue of the historically active volcanoes of Alaska. U S Geol Surv Open-File Rpt, 98-582: 1-104.

Motyka R J, Liss S A, Nye C J, Moorman M A, 1993. Geothermal resources of the Aleutian arc. Alaska Div Geol Geophys Surv, Prof Rpt, no 114, 17 p and 4 map sheets.

Siebert L, Beget J E, Glicken H, 1995. The 1883 and late-prehistoric eruptions of Augustine volcano, Alaska. J Volc Geotherm Res, 66: 367-395.

Siebert L, Glicken H, Kienle J, 1989. Debris avalanches and lateral blasts at Mount St. Augustine volcano, Alaska. Natl Geog Res, 5: 232-249.

Smith R L, Shaw H R, Luedke R G, Russell S L, 1978. Comprehensive tables giving physical data and thermal energy estimates for young igneous systems of the United States. U S Geol Surv Open-File Rpt, 78-925: 1-25.

Swanson S E, Kienle J, 1988. The 1986 eruption of Mount St. Augustine: field test of a hazard evaluation. J Geophys Res, 93: 4500-4520.

Waitt R B, 2010. Ejecta and landslides from Augustine volcano before 2006. In: Power J A, Coombs M L, Freymueller J T (eds) {U S Geol Surv Prof Pap}, 1769: 297-319.

Waitt R B, Beget J E, 1996. Provisional geologic map of Augustine volcano, Alaska. U S Geol Surv Open-File Rpt, 96-516: 1-44.

Waitt R B, Beget J E, 2009. Volcanic processes and geology of Augustine volcano, Alaska. U S Geol Surv Prof Pap, 1762: 1-78.

Waythomas C F, Waitt R B, 1998. Preliminary volcano-hazard assessment for Augustine volcano, Alaska. U S Geol Surv Open-File Rpt, 98-106: 1-39.

Augustine volcano, rising above Kamishak Bay in the southern Cook Inlet about 290 km SW of Anchorage, is the most active volcano of the eastern Aleutian arc. It consists of a complex of overlapping summit lava domes surrounded by an apron of volcaniclastic debris that descends to the sea on all sides. Few lava flows are exposed; the flanks consist mainly of debris-avalanche and pyroclastic-flow deposits formed by repeated collapse and regrowth of the volcano's summit. The latest episode of edifice collapse occurred during Augustine's largest historical eruption in 1883; subsequent dome growth has restored the volcano to a height comparable to that prior to 1883. The oldest dated volcanic rocks on Augustine are more than 40,000 years old. At least 11 large debris avalanches have reached the sea during the past 1800-2000 years, and five major pumiceous tephras have been erupted during this interval. Historical eruptions have typically consisted of explosive activity with emplacement of pumiceous pyroclastic-flow deposits followed by lava dome extrusion with associated block-and-ash flows.