HVO Mauna Loa Status

Recent Mauna Loa Status Reports, Updates, and Information Releases

HAWAIIAN VOLCANO OBSERVATORY MONTHLY UPDATE
U.S. Geological Survey
Monday, April 6, 2015 3:36 PM PDT (Monday, April 6, 2015 22:36 UTC)


MAUNA LOA VOLCANO (VNUM #332020)
19°28'30" N 155°36'29" W, Summit Elevation 13681 ft (4170 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Monitoring data through the month of March 2015:

Seismicity: Seismicity at Mauna Loa remains elevated in several parts of the volcano. Earthquake rates on the Upper Southwest Rift Zone (Sulfur Cone) and Mokuʻāweoweo Crater remain elevated, with over 100 earthquakes occurring in March. Though there were no swarms on the west flank of Mauna Loa, earthquake rates remained above background with approximately 25 earthquakes occurring in March. All earthquakes in the past month have been small relative to earthquake sequences observed before eruptions in 1975 and 1984.

Deformation: The pattern of motion of continuously recording GPS stations in March indicate that inflation continues. Average velocities since the start of the current inflationary period in mid-2014 are not quite as fast, but very similar to those observed in 2005 which, along with a short period in 2002, had been the time of highest observed velocities since GPS monitoring started in the mid-1990's.


Background: Re-inflation of Mauna Loa's shallow magma storage reservoirs started immediately following the most recent eruption in 1984, then turned to deflation for almost a decade. In mid-2002, inflation started again, just after a brief swarm of deep long-period (LP) earthquakes. A more intense swarm of several thousand deep Long Period (LP) earthquakes occurred in late 2004, immediately preceding a dramatic increase in inflation rate. Inflation slowed again in 2006, ceased altogether in late 2009, and resumed slowly in late 2010.

Rising gradually to more than 4 km above sea level, Mauna Loa is the largest active volcano on our planet. Its long submarine flanks descend to the sea floor an additional 5 km, and the sea floor in turn is depressed by Mauna Loa's great mass another 8 km. This makes the volcano's summit about 17 km (56,000 ft) above its base! The enormous volcano covers half of the Island of Hawai`i and by itself amounts to about 85 percent of all the other Hawaiian Islands combined.

Mauna Loa is the largest active volcano on Earth and is among Earth's most active volcanoes, having erupted 33 times since its first well-documented historical eruption in 1843. Its most recent eruption was in 1984. For more information on Mauna Loa, see the USGS Fact sheet available at http://pubs.usgs.gov/fs/2012/3104/fs2012-3104.pdf.

CONTACT INFORMATION:
askHVO@usgs.gov

The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawai`i.
HAWAIIAN VOLCANO OBSERVATORY MONTHLY UPDATE
U.S. Geological Survey
Thursday, March 5, 2015 6:34 AM PST (Thursday, March 5, 2015 14:34 UTC)


MAUNA LOA VOLCANO (VNUM #332020)
19°28'30" N 155°36'29" W, Summit Elevation 13681 ft (4170 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Monitoring data through the month of February 2015:

Seismicity: Seismicity at Mauna Loa remains elevated in several parts of the volcano. Earthquake rates on the Upper Southwest Rift Zone (Sulfur Cone) and Mokuʻāweoweo Caldera remain elevated, however earthquakes rates are lower than seen in previous months. Though there were no swarms on the west flank of Mauna Loa, earthquake rates remained above background with approximately 14 earthquakes occurring in the past month. All earthquakes in the past month have been small relative to earthquake sequences observed before eruptions in 1975 and 1984.

Deformation: GPS data suggest that inflation may be continuing, but at very low rates. The interferograms available for Mauna Loa that include acquisitions in February are ambiguous, as they appear to be dominated by atmospheric effects.

Gas: No significant changes in SO2, CO2 were recorded by the Mokuʻāweoweo Caldera gas and temperature monitors during February. Fumarole temperature continued to stabilize following the temperature anomaly that occurred between early October and late November, 2014. Temperature varied between 77 and 79 degrees C,nominally except for a brief spike on 2/24, up to 80 degrees.

Background: Re-inflation of Mauna Loa's shallow magma storage reservoirs started immediately following the most recent eruption in 1984, then turned to deflation for almost a decade. In mid-2002, inflation started again, just after a brief swarm of deep long-period (LP) earthquakes. A more intense swarm of several thousand deep Long Period (LP) earthquakes occurred in late 2004, immediately preceding a dramatic increase in inflation rate. Inflation slowed again in 2006, ceased altogether in late 2009, and resumed slowly in late 2010.

Rising gradually to more than 4 km above sea level, Mauna Loa is the largest active volcano on our planet. Its long submarine flanks descend to the sea floor an additional 5 km, and the sea floor in turn is depressed by Mauna Loa's great mass another 8 km. This makes the volcano's summit about 17 km (56,000 ft) above its base! The enormous volcano covers half of the Island of Hawai`i and by itself amounts to about 85 percent of all the other Hawaiian Islands combined.

Mauna Loa is the largest active volcano on Earth and is among Earth's most active volcanoes, having erupted 33 times since its first well-documented historical eruption in 1843. Its most recent eruption was in 1984. For more information on Mauna Loa, see the USGS Fact sheet available at http://pubs.usgs.gov/fs/2012/3104/fs2012-3104.pdf.

CONTACT INFORMATION:
askHVO@usgs.gov

The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawai`i.
HAWAIIAN VOLCANO OBSERVATORY MONTHLY UPDATE
U.S. Geological Survey
Wednesday, February 11, 2015 10:41 AM PST (Wednesday, February 11, 2015 18:41 UTC)


MAUNA LOA VOLCANO (VNUM #332020)
19°28'30" N 155°36'29" W, Summit Elevation 13681 ft (4170 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Seismicity continued to be slightly elevated; deformation patterns suggest continuing inflation over the past month.

Monitoring data through the month of January 2015:

Seismicity: Seismicity at Mauna Loa remains elevated in several parts of the volcano. Earthquake rates on the Upper Southwest Rift Zone (Sulfur Cone) and Mokuʻāweoweo Caldera remain elevated, with rates similar to that seen in previous months. Though there were no swarms on the west flank of Mauna Loa, earthquake rates remained above background with approximately 20 earthquakes occurring in the past month. All earthquakes in the past month have been small relative to earthquake sequences observed before eruptions in 1975 and 1984.

Deformation: GPS data suggest that inflation continues after a lull in December, but rates are too low to discern the whether the sources have changed. The single satellite radar interferogram available for Mauna Loa for January is ambiguous, as it is likely dominated by atmospheric effects not related to volcanic factors.

Gas: No significant changes in SO2, CO2 were recorded by the Mokuʻāweoweo Caldera gas and temperature monitors during January. Fumarole temperature continued to stabilize following the temperature anomaly that occurred between early October and late November, 2014. Temperature varied between 77 and 78 degrees C, except for a precipitation-induced decrease at the beginning of the month.

Background: Re-inflation of Mauna Loa's shallow magma storage reservoirs started immediately following the most recent eruption in 1984, then turned to deflation for almost a decade. In mid-2002, inflation started again, just after a brief swarm of deep long-period (LP) earthquakes. A more intense swarm of several thousand deep Long Period (LP) earthquakes occurred in late 2004, immediately preceding a dramatic increase in inflation rate. Inflation slowed again in 2006, ceased altogether in late 2009, and resumed slowly in late 2010.

Rising gradually to more than 4 km above sea level, Mauna Loa is the largest active volcano on our planet. Its long submarine flanks descend to the sea floor an additional 5 km, and the sea floor in turn is depressed by Mauna Loa's great mass another 8 km. This makes the volcano's summit about 17 km (56,000 ft) above its base! The enormous volcano covers half of the Island of Hawai`i and by itself amounts to about 85 percent of all the other Hawaiian Islands combined.

Mauna Loa is the largest active volcano on Earth and is among Earth's most active volcanoes, having erupted 33 times since its first well-documented historical eruption in 1843. Its most recent eruption was in 1984. For more information on Mauna Loa, see the USGS Fact sheet available at http://pubs.usgs.gov/fs/2012/3104/fs2012-3104.pdf.

CONTACT INFORMATION:
askHVO@usgs.gov

The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawai`i.
HAWAIIAN VOLCANO OBSERVATORY MONTHLY UPDATE
U.S. Geological Survey
Wednesday, January 28, 2015 2:42 PM PST (Wednesday, January 28, 2015 22:42 UTC)


MAUNA LOA VOLCANO (VNUM #332020)
19°28'30" N 155°36'29" W, Summit Elevation 13681 ft (4170 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Seismicity continued to be slightly elevated; deformation patterns may suggest slowed inflation over the past month.

Monitoring data through the month of December 2014:

Seismicity: Seismicity at Mauna Loa remains elevated in several parts of the volcano. Earthquake rates on the Upper Southwest Rift Zone (Sulfur Cone) remain elevated, with rates similar to that seen in previous months. Seismicity rates in the Mokuʻāweoweo Crater remains elevated, though lower than last month, with approximately 15 very small events in the past month at shallow (<5 km) depths. There were approximately 14 earthquakes in the past month on the west flank of Mauna Loa. All earthquakes in the past month have been small relative to earthquake sequences observed before eruptions in 1975 and 1984.

Deformation: GPS data show a distinct slowing, perhaps even cessation, of inflation in December. Inflation rate has been highly variable since the start of the current, renewed inflationary period.

Gas: No significant changes in SO2, CO2 were recorded by the Mokuʻāweoweo Crater gas monitor. The fumarole temperature excursion that began around 21 September and peaked two months later appears to be in a decided decline. As discussed earlier, this numerically small temperature increase deviates significantly from the seasonal trend observed at this site since fumarole temperature monitoring began in 2005. Between the beginning of October and the beginning of December, the average temperature increased from ca. 72 deg C to 79 deg C. The major portion of the increase occurred between 11/1 and 11/21. The decline began earnestly on 12/1, and continues. By month's end, the fumarole temperature sensor recorded 77 degrees C.

Background: Re-inflation of Mauna Loa's shallow magma storage reservoirs started immediately following the most recent eruption in 1984, then turned to deflation for almost a decade. In mid-2002, inflation started again, just after a brief swarm of deep long-period (LP) earthquakes. A more intense swarm of several thousand deep Long Period (LP) earthquakes occurred in late 2004, immediately preceding a dramatic increase in inflation rate. Inflation slowed again in 2006, ceased altogether in late 2009, and resumed slowly in late 2010.

Rising gradually to more than 4 km above sea level, Mauna Loa is the largest active volcano on our planet. Its long submarine flanks descend to the sea floor an additional 5 km, and the sea floor in turn is depressed by Mauna Loa's great mass another 8 km. This makes the volcano's summit about 17 km (56,000 ft) above its base! The enormous volcano covers half of the Island of Hawai`i and by itself amounts to about 85 percent of all the other Hawaiian Islands combined.

Mauna Loa is the largest active volcano on Earth and is among Earth's most active volcanoes, having erupted 33 times since its first well-documented historical eruption in 1843. Its most recent eruption was in 1984. For more information on Mauna Loa, see the USGS Fact sheet available at http://pubs.usgs.gov/fs/2012/3104/fs2012-3104.pdf.

CONTACT INFORMATION:
askHVO@usgs.gov

The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawai`i.
HAWAIIAN VOLCANO OBSERVATORY MONTHLY UPDATE
U.S. Geological Survey
Friday, December 5, 2014 10:02 AM PST (Friday, December 5, 2014 18:02 UTC)


MAUNA LOA VOLCANO (VNUM #332020)
19°28'30" N 155°36'29" W, Summit Elevation 13681 ft (4170 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Seismicity continued to be slightly elevated; deformation patterns may suggest renewed inflation.

Monitoring data through the month of November 2014:

Seismicity: Earthquake rates on the Upper Southwest Rift Zone (Sulfur Cone) remain elevated, with slightly stronger earthquakes than seen in previous months. Seismicity rates in the Mokuʻāweoweo Crater remains elevated with approximately 50 very small events in the past month at shallow (<5 km) depths. There were approximately 15 earthquakes in the past month on the west flank of Mauna Loa. All earthquakes in the past month have been small relative to earthquake sequences observed before eruptions in 1975 and 1984.

Deformation: GPS data continue to show a broad pattern of displacements suggesting inflation of one or more magma reservoirs, with the majority of the volume accumulating in a dike-like body beneath the caldera and upper SW rift zone. Displacements continued at the same average rates measured since the increase in rates in late June/early July.

Gas: No significant changes in SO2, CO2 were recorded by the Mokuʻāweoweo gas monitor. Notably though, we have continued to observe an increasing fumarole temperature. As discussed last month, this temperature increase, while numerically small, deviates significantly from the seasonal trend observed at this site since fumarole temperature began in 2005. Between the beginning of October and the beginning of December, this average temperature increased from ca. 72 deg C to 79 deg C. The major portion of this change occurred between 11/1 and 11/21.

Background: Re-inflation of Mauna Loa's shallow magma storage reservoirs started immediately following the most recent eruption in 1984, then turned to deflation for almost a decade. In mid-2002, inflation started again, just after a brief swarm of deep long-period (LP) earthquakes. A more intense swarm of several thousand deep Long Period (LP) earthquakes occurred in late 2004, immediately preceding a dramatic increase in inflation rate. Inflation slowed again in 2006, ceased altogether in late 2009, and resumed slowly in late 2010.

Rising gradually to more than 4 km above sea level, Mauna Loa is the largest active volcano on our planet. Its long submarine flanks descend to the sea floor an additional 5 km, and the sea floor in turn is depressed by Mauna Loa's great mass another 8 km. This makes the volcano's summit about 17 km (56,000 ft) above its base! The enormous volcano covers half of the Island of Hawai`i and by itself amounts to about 85 percent of all the other Hawaiian Islands combined.

Mauna Loa is the largest active volcano on Earth and is among Earth's most active volcanoes, having erupted 33 times since its first well-documented historical eruption in 1843. Its most recent eruption was in 1984. For more information on Mauna Loa, see the USGS Fact sheet available at http://pubs.usgs.gov/fs/2012/3104/fs2012-3104.pdf.

CONTACT INFORMATION:
askHVO@usgs.gov

The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawai`i.
HAWAIIAN VOLCANO OBSERVATORY MONTHLY UPDATE
U.S. Geological Survey
Saturday, November 8, 2014 3:50 PM PST (Saturday, November 8, 2014 23:50 UTC)


MAUNA LOA VOLCANO (VNUM #332020)
19°28'30" N 155°36'29" W, Summit Elevation 13681 ft (4170 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Seismicity continued to be slightly elevated; deformation patterns may suggest renewed inflation.

Monitoring data through the month of October 2014:

Seismicity: Earthquake rates on the Upper Southwest Rift Zone (Sulfur Cone) remain elevated, though similar to the past couple of months. Seismicity rates in the Mokuʻāweoweo Caldera remains elevated with approximately 40 very small events in the past month at shallow (<5 km) depths. All earthquakes in the past month have been small relative to earthquake sequences observed before eruptions in 1975 and 1984.

Deformation: GPS data continue to show a broad pattern of displacements suggesting inflation. Preliminary modeling shows the data to be consistent with inflation of one or more magma reservoirs, with the majority of the volume accumulating in a dike-like body beneath the caldera and upper rift zones. Reinflation may have started very slowly in April or May of this year. Displacement rates have been variable, with higher rates in July and August, slowing in September and possibly slightly picking up again near the end of October.

Gas: No significant changes in SO2, CO2 were recorded by the Mokuʻāweoweo gas monitor; however, a minor deviation in fumarole temperature was recorded over the past two months. The correlation between fumarole temperature increase, elevated seismic tremor levels, and tilt values reported in September was coincidental. This month, we've continued to record a fairly sharp anomalous 2-3 degree C temperature increase.

Background: Re-inflation of Mauna Loa's shallow magma storage reservoirs started immediately following the most recent eruption in 1984, then turned to deflation for almost a decade. In mid-2002, inflation started again, just after a brief swarm of deep long-period (LP) earthquakes. A more intense swarm of several thousand deep Long Period (LP) earthquakes occurred in late 2004, immediately preceding a dramatic increase in inflation rate. Inflation slowed again in 2006, ceased altogether in late 2009, and resumed slowly in late 2010.

Rising gradually to more than 4 km above sea level, Mauna Loa is the largest active volcano on our planet. Its long submarine flanks descend to the sea floor an additional 5 km, and the sea floor in turn is depressed by Mauna Loa's great mass another 8 km. This makes the volcano's summit about 17 km (56,000 ft) above its base! The enormous volcano covers half of the Island of Hawai`i and by itself amounts to about 85 percent of all the other Hawaiian Islands combined.

Mauna Loa is the largest active volcano on Earth and is among Earth's most active volcanoes, having erupted 33 times since its first well-documented historical eruption in 1843. Its most recent eruption was in 1984. For more information on Mauna Loa, see the USGS Fact sheet available at http://pubs.usgs.gov/fs/2012/3104/fs2012-3104.pdf.

CONTACT INFORMATION:
askHVO@usgs.gov

The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawai`i.
HAWAIIAN VOLCANO OBSERVATORY MONTHLY UPDATE
U.S. Geological Survey
Wednesday, October 15, 2014 1:57 PM PDT (Wednesday, October 15, 2014 20:57 UTC)


MAUNA LOA VOLCANO (VNUM #332020)
19°28'30" N 155°36'29" W, Summit Elevation 13681 ft (4170 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Seismicity continued to be slightly elevated; deformation patterns may suggest renewed inflation.

Monitoring data through the month of September 2014:

Seismicity: Seismicity at Mauna Loa remains elevated in several parts of the volcano. In late September, a swarm occurred to the west of Moku`āweoweo Crater. The swarm had a maximum magnitude of 2.4 and several events that were large enough to be located. In total, there were up to 150 separate earthquakes that were part of this swarm, most too small to be recorded on enough stations to be accurately located, however we infer that their location is similar to the formal locations of the larger events. The same area had a swarm in September and October of 2013. Several long period earthquakes were present at depths from 50 km to the shallow edifice, with most LP earthquakes between 9 and 15 km depth. Earthquake rates on the Upper Southwest Rift Zone (Sulfur Cone) remain elevated, though similar to the past couple of months. Seismicity rates in the Moku`āweoweo Crater increased over previous months with approximately 50 very small events in the past month at shallow (<5 km) depths. All earthquakes in the past month have been small relative to earthquake sequences observed before eruptions in 1975 and 1984.

Deformation: On Mauna Loa, GPS data continue to show a broad pattern of displacements suggesting inflation. Preliminary modeling shows the data to be consistent with inflation of one or more magma reservoirs, with the majority of the volume accumulating in a dike-like body beneath the caldera and upper rift zones. Reinflation may have started very slowly in April or May of this year. Displacement rates have been variable, with higher rates in July and August and slowing again in September.

Gas: No significant changes in SO2 or CO2 were recorded by the Moku`āweoweo gas monitor in September.

Background: Re-inflation of Mauna Loa's shallow magma storage reservoirs started immediately following the most recent eruption in 1984, then turned to deflation for almost a decade. In mid-2002, inflation started again, just after a brief swarm of deep long-period (LP) earthquakes. A more intense swarm of several thousand deep Long Period (LP) earthquakes occurred in late 2004, immediately preceding a dramatic increase in inflation rate. Inflation slowed again in 2006, ceased altogether in late 2009, and resumed slowly in late 2010.

Rising gradually to more than 4 km above sea level, Mauna Loa is the largest active volcano on our planet. Its long submarine flanks descend to the sea floor an additional 5 km, and the sea floor in turn is depressed by Mauna Loa's great mass another 8 km. This makes the volcano's summit about 17 km (56,000 ft) above its base! The enormous volcano covers half of the Island of Hawai`i and by itself amounts to about 85 percent of all the other Hawaiian Islands combined.

Mauna Loa is the largest active volcano on Earth and is among Earth's most active volcanoes, having erupted 33 times since its first well-documented historical eruption in 1843. Its most recent eruption was in 1984. For more information on Mauna Loa, see the USGS Fact sheet available at http://pubs.usgs.gov/fs/2012/3104/fs2012-3104.pdf.

CONTACT INFORMATION:
askHVO@usgs.gov

The Hawaiian Volcano Observatory is one of five volcano observatories within the U.S. Geological Survey and is responsible for monitoring volcanoes and earthquakes in Hawai`i.

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For more information about the Volcano Alert Level and Aviation Color Code, please see the U.S. Geological Survey's Alert Notification System for Volcanic Activity Fact Sheet (pdf) or the USGS Volcanic Activity Alert-Notification System web page.