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Recent Kilauea Status Reports, Updates, and Information Releases
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Tuesday, November 4, 2008 07:38 HST (Tuesday, November 4, 2008 17:38 UTC)
KILAUEA VOLCANO (CAVW#1302-01-)
19.42°N 155.29°W, Summit Elevation 4091 ft (1247 m)
Volcano Alert Level: WATCH
Aviation Color Code: ORANGE
This report on the status of Kilauea volcanic activity, in addition to maps, photos, and webcam images (available using the menu bar above), was prepared by the USGS Hawaiian Volcano Observatory (HVO). Hawai`i Volcanoes National Park status can be found at http://www.nps.gov/havo/ or 985-6000. Hawai`i County Viewing Area status can be found at 961-8093.
Activity Summary for last 24 hours: Sunday's DI tilt event is completed. Sulfur dioxide emission rates from the Halema`uma`u and the Pu`u `O`o vents remain high. Tephra production from the Halema`uma`u vent remains small. At the east rift eruption site, lava flow may have paused in response to the ongoing DI tilt event.
Last 24 hours at Kilauea summit: Vent glow was rarely visible and too weak to be recorded by the webcam overnight. This morning, the gas plume arcs up and over the crater rim and is moving low and southwestward over the Ka`u Desert.
Sulfur dioxide emission rates remain elevated and variable. The most recent average measurement was 700 tonnes/day on November 3, compared to the 2003-2007 average rate of 140 tonnes/day.
Small amounts of tephra, mostly ash-sized spatter, continue to be produced and deposited downwind of the vent. The distant surf sounds continue to be heard near the vent.
The network of tiltmeters within Kilauea caldera recorded inflation of a source in the south caldera completing the ongoing DI tilt event. The GPS receiver networks (less sensitive than tiltmeters) recorded weak contraction (barely 1 cm per month).
Seismic activity continued at low levels focused on the south caldera; tremor levels returned to pre-DI tilt event levels with episodic tremor bursts. A total of 13 earthquakes were located beneath Kilauea or nearby, including 3 beneath the south caldera and 2 on south flank faults, with the number of RB2S2BL earthquakes at background values around 40/day.
Last 24 hours at the middle east rift zone vents and flow field: Magma continues to degas through Pu`u `O`o Crater. The most recent sulfur dioxide measurement of 1,700 tonnes/day on November 3 is at the 2003-2007 average of about 1,700 tonnes/day for this vent; this is the first Pu`u `O`o emission rate in the average range since early September. No incandescence was observed within the crater overnight.
The tiltmeter on the north side of Pu`u `O`o recorded follow up inflation of the ongoing DI tilt event at 6 am yesterday, only about 15 minutes after the summit inflation started. GPS stations spanning the crater (less sensitive than tiltmeters) recorded about 4 cm of contraction over the past 3 months. Seismic tremor levels near Pu`u `O`o and the TEB vent remain at low values increasing about 25% after 8 pm.
Lava from the TEB vent and the rootless shield complex flows through tubes to the ocean. CD officials reported continuing surface activity on the pali and a small steam plume and weak activity at the ocean entry yesterday. No incandescence was seen overnight in the area from the east rift eruption site to the top of the pali. After high-altitude clouds cleared the area, GOES-WEST imagery showed a distinct thermal anomaly at 6 am suggesting continuing surface flow activity this morning. CD officials this morning report that the surface flows on the pali continue as does a small plume from the ocean entry.
Definitions of terms used in the update:
FLIR: Forward Looking InfraRed, a camera which directly images heat rather than visible light. If volcanic fume is not too rich in water vapor, a FLIR can see through it to image hot surfaces.
pali: Hawaiian word for cliff or steep incline. In the context of the TEB flow field, 'pali' usually refers to Pulama pali that bisects the abandoned Royal Gardens subdivision.
CD: Hawai`i County Civil Defense
DOH air quality monitoring: see Hawai`i State Department of Health Air Quality website http://hawaii.gov/doh/air-quality/index.html .
bomb: lava fragment ejected into the air while molten acquiring aerodynamic shapes in flight; the term is restricted to pieces larger than 6.4 cm (2.5 in.). See http://volcanoes.usgs.gov/Products/Pglossary/bomb.html
hybrid, or explosion, seismic signals: complex earthquakes that are a hybrid of different signals. They start as a high frequency earthquake, similar to typical rock-breaking or rock fall events, that transitions to very long, 20-30 second, period (VLP) oscillations that continue for several minutes. At HVO, we observed these signals with the four small Halema`uma`u explosive eruptions in March, April, and August 2008. Several more similar signals, some as strong as the explosion signals associated with the four explosive eruptions, have been recorded without obvious evidenceof surface eruption such as rock fragments or other debris.
MODIS satellite: a NASA satellite pair, Aqua and Terra, which passes over Hawai`i twice a day. During daylight hours, the images are taken at about 11 am and 2 pm H.s.t. This imagery can be viewed about 3-5 hours after acquisition at http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=AERONET_Mauna_Loa.
GOES-WEST satellite: a geostationary NOAA satellite used most often for weather tracking. Images are typically acquired every 15 minutes. The loop http://www.ssd.noaa.gov/VAAC/kilauea/sloop-vis.html is posted by the Washington DC Volcanic Ash Advisory Center for the purpose of tracking emissions from Hawai`i volcanoes. The imagery automatically switches from infrared at night to visual during the day. Recently, it has been useful for tracking volcanic gas emissions from Halema`uma`u, Pu`u `O`o, and the Waikupanaha ocean entry during the day and hot lava flows at night.
Volcano Watch: weekly newspaper-like article written by HVO scientists on a volcano topic of interest. These articles are usually printed in the Sunday editions of the Hawai`i Island newspapers Hawaii Tribune Herald and West Hawaii Today. More than 800 of these articles have been written and are archived on the HVO website (menu at the bottom of the homepage hvo.wr.usgs.gov).
VLP seismic tremor: seismic tremor is continuous ground vibrations simultaneously at many different frequencies. VLP is a very long period or very low frequency component which, at the Halema`uma`u vent, has a period of 20-30 seconds or a frequency of 0.03-0.05 cycles per second (Hertz or Hz).
RB2S2BL earthquakes: earthquakes that were recorded but too small to be located. These quakes have magnitudes less than 1.7 and may only be recorded on one or two seismometers. Recording at a minimum of 4 seismometer sites is required to locate an earthquake.
wink: an abrupt shutting off of incandescence at a vent lasting for several minutes. At the Halema`uma`u vent, winks usually start with or immediately follow a small, local earthquake. The diminishment of incandescence is due to the plume changing from translucent to opaque with rock dust.
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
microradian: a measure of angle equivalent to 0.000057 degrees.
ppm: parts-per-million; 10,000 ppm = 1 %.
littoral cone: usually small cones built near active ocean entries; the cones are constructed of tephra from steam explosions that are sometimes produced when 1,150 degree C lava enters the 25 degree C ocean.
incandescence: the production of visible light from a hot surface. The color of the light is related to the temperature of the surface. Some surfaces can display dull red incandescence at temperatures as low as 430 degrees Centigrade (806 degrees Fahrenheit). By contrast, molten lava displays bright orange to orange-yellow light from surfaces that are hotter than 900 degrees C (1,650 degrees F).
tephra: all material deposited by fallout from an eruption-related plume, regardless of size.
ash: tephra less than 2 mm (5/64 inches) in size.
TEB: Thanksgiving Eve Breakout, the designation used for lava flows that started with a breakout on November 21, 2007.
DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a volcanic event of uncertain significance. DI events are recorded by tiltmeters at Kilauea summit as an abrupt deflation of up to a few microradians in magnitude lasting several hours to 2-3 days followed by an abrupt inflation of approximately equal magnitude. The tilt events are usually accompanied by an increase in summit tremor during the deflation phase. A careful analysis of these events suggests that they may be related to changes in magma supply to a storage reservoir at less than 1 km depth, just east of Halema`uma`u crater. Usually, though not always, these changes propagate through the magma conduit from the summit to the eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by 1-2 hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
Maps, photos, webcam views, and other information about Kilauea Volcano are available at http://volcano.wr.usgs.gov/kilaueastatus.php. A daily update summary is available by phone at (808) 967-8862.
A map with details of earthquakes located within the past two weeks can be found at http://tux.wr.usgs.gov/
A definition of alert levels can be found at http://volcanoes.usgs.gov/2006/warnschemes.html
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Monday, November 3, 2008 06:40 HST (Monday, November 3, 2008 16:40 UTC)
KILAUEA VOLCANO (CAVW#1302-01-)
19.42°N 155.29°W, Summit Elevation 4091 ft (1247 m)
Volcano Alert Level: WATCH
Aviation Color Code: ORANGE
This report on the status of Kilauea volcanic activity, in addition to maps, photos, and webcam images (available using the menu bar above), was prepared by the USGS Hawaiian Volcano Observatory (HVO). Hawai`i Volcanoes National Park status can be found at http://www.nps.gov/havo/ or 985-6000. Hawai`i County Viewing Area status can be found at 961-8093.
Activity Summary for last 24 hours: A DI tilt event started with deflation at 7:20 am yesterday followed by inflation at 5:46 am this morning. Sulfur dioxide emission rates from the Halema`uma`u and the Pu`u `O`o vents remain high although the emissions from Pu`u `O`o have been decreasing since August. Tephra production from the Halema`uma`u vent remains small. At the east rift eruption site, lava flow may have paused in response to the ongoing DI tilt event.
Last 24 hours at Kilauea summit: Vent glow was not often visible and too weak to be recorded by the webcam overnight. This morning, the gas plume arcs up and over the crater rim and is moving low and southwestward over the Ka`u Desert.
Sulfur dioxide emission rates remain elevated and variable. The most recent average measurement was 500 tonnes/day on October 31, compared to the 2003-2007 average rate of 140 tonnes/day.
The network of tiltmeters within Kilauea caldera recorded the initial deflation of a DI tilt event at 7:20 am yesterday followed by inflation starting at 5:46 am this morning. The GPS receiver networks (less sensitive than tiltmeters) recorded weak contraction (barely 1 cm per month).
Seismic activity continued at low levels focused on the south caldera; tremor levels almost doubled during the DI deflation. A total of 12 earthquakes were located beneath Kilauea or nearby, including 6 beneath the south caldera and 3 on south flank faults, with the number of RB2S2BL earthquakes remaining slightly elevated at values around 50/day.
Last 24 hours at the middle east rift zone vents and flow field: Magma continues to degas through Pu`u `O`o Crater. The most recent sulfur dioxide measurement of 1,200 tonnes/day on October 30 is below the 2003-2007 average of about 1,700 tonnes/day for this vent; Pu`u `O`o emission rates have been slowly declining since early August. No incandescence was observed within the crater overnight.
The tiltmeter on the north side of Pu`u `O`o recorded the initial deflation of an ongoing DI tilt event at 9:30 am yesterday. GPS stations spanning the crater (less sensitive than tiltmeters) recorded about 7 cm of contraction over the past 3 months but at a decreased rate since 10/27. Seismic tremor levels near Pu`u `O`o and the TEB vent remain at low values decreasing during the DI deflation.
Lava from the TEB vent and the rootless shield complex flows through tubes to the ocean. Yesterday's MODIS images showed thermal anomalies within the abandoned Royal Gardens subdivision, indicating continuing surface flow activity on the pali, and a distinct steam plume from the ocean entry at 2 pm. No incandescence was seen overnight in the area from the east rift eruption site to the top of the pali. GOES-WEST imagery showed diminishing thermal anomalies this morning suggesting that surface flow activity has slowed in response to the ongoing DI tilt event.
Definitions of terms used in the update:
FLIR: Forward Looking InfraRed, a camera which directly images heat rather than visible light. If volcanic fume is not too rich in water vapor, a FLIR can see through it to image hot surfaces.
pali: Hawaiian word for cliff or steep incline. In the context of the TEB flow field, 'pali' usually refers to Pulama pali that bisects the abandoned Royal Gardens subdivision.
CD: Hawai`i County Civil Defense
DOH air quality monitoring: see Hawai`i State Department of Health Air Quality website http://hawaii.gov/doh/air-quality/index.html .
bomb: lava fragment ejected into the air while molten acquiring aerodynamic shapes in flight; the term is restricted to pieces larger than 6.4 cm (2.5 in.). See http://volcanoes.usgs.gov/Products/Pglossary/bomb.html
hybrid, or explosion, seismic signals: complex earthquakes that are a hybrid of different signals. They start as a high frequency earthquake, similar to typical rock-breaking or rock fall events, that transitions to very long, 20-30 second, period (VLP) oscillations that continue for several minutes. At HVO, we observed these signals with the four small Halema`uma`u explosive eruptions in March, April, and August 2008. Several more similar signals, some as strong as the explosion signals associated with the four explosive eruptions, have been recorded without obvious evidenceof surface eruption such as rock fragments or other debris.
MODIS satellite: a NASA satellite pair, Aqua and Terra, which passes over Hawai`i twice a day. During daylight hours, the images are taken at about 11 am and 2 pm H.s.t. This imagery can be viewed about 3-5 hours after acquisition at http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=AERONET_Mauna_Loa.
GOES-WEST satellite: a geostationary NOAA satellite used most often for weather tracking. Images are typically acquired every 15 minutes. The loop http://www.ssd.noaa.gov/VAAC/kilauea/sloop-vis.html is posted by the Washington DC Volcanic Ash Advisory Center for the purpose of tracking emissions from Hawai`i volcanoes. The imagery automatically switches from infrared at night to visual during the day. Recently, it has been useful for tracking volcanic gas emissions from Halema`uma`u, Pu`u `O`o, and the Waikupanaha ocean entry during the day and hot lava flows at night.
Volcano Watch: weekly newspaper-like article written by HVO scientists on a volcano topic of interest. These articles are usually printed in the Sunday editions of the Hawai`i Island newspapers Hawaii Tribune Herald and West Hawaii Today. More than 800 of these articles have been written and are archived on the HVO website (menu at the bottom of the homepage hvo.wr.usgs.gov).
VLP seismic tremor: seismic tremor is continuous ground vibrations simultaneously at many different frequencies. VLP is a very long period or very low frequency component which, at the Halema`uma`u vent, has a period of 20-30 seconds or a frequency of 0.03-0.05 cycles per second (Hertz or Hz).
RB2S2BL earthquakes: earthquakes that were recorded but too small to be located. These quakes have magnitudes less than 1.7 and may only be recorded on one or two seismometers. Recording at a minimum of 4 seismometer sites is required to locate an earthquake.
wink: an abrupt shutting off of incandescence at a vent lasting for several minutes. At the Halema`uma`u vent, winks usually start with or immediately follow a small, local earthquake. The diminishment of incandescence is due to the plume changing from translucent to opaque with rock dust.
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
microradian: a measure of angle equivalent to 0.000057 degrees.
ppm: parts-per-million; 10,000 ppm = 1 %.
littoral cone: usually small cones built near active ocean entries; the cones are constructed of tephra from steam explosions that are sometimes produced when 1,150 degree C lava enters the 25 degree C ocean.
incandescence: the production of visible light from a hot surface. The color of the light is related to the temperature of the surface. Some surfaces can display dull red incandescence at temperatures as low as 430 degrees Centigrade (806 degrees Fahrenheit). By contrast, molten lava displays bright orange to orange-yellow light from surfaces that are hotter than 900 degrees C (1,650 degrees F).
tephra: all material deposited by fallout from an eruption-related plume, regardless of size.
ash: tephra less than 2 mm (5/64 inches) in size.
TEB: Thanksgiving Eve Breakout, the designation used for lava flows that started with a breakout on November 21, 2007.
DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a volcanic event of uncertain significance. DI events are recorded by tiltmeters at Kilauea summit as an abrupt deflation of up to a few microradians in magnitude lasting several hours to 2-3 days followed by an abrupt inflation of approximately equal magnitude. The tilt events are usually accompanied by an increase in summit tremor during the deflation phase. A careful analysis of these events suggests that they may be related to changes in magma supply to a storage reservoir at less than 1 km depth, just east of Halema`uma`u crater. Usually, though not always, these changes propagate through the magma conduit from the summit to the eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by 1-2 hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
Maps, photos, webcam views, and other information about Kilauea Volcano are available at http://volcano.wr.usgs.gov/kilaueastatus.php. A daily update summary is available by phone at (808) 967-8862.
A map with details of earthquakes located within the past two weeks can be found at http://tux.wr.usgs.gov/
A definition of alert levels can be found at http://volcanoes.usgs.gov/2006/warnschemes.html
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Sunday, November 2, 2008 07:49 HST (Sunday, November 2, 2008 17:49 UTC)
KILAUEA VOLCANO (CAVW#1302-01-)
19.42°N 155.29°W, Summit Elevation 4091 ft (1247 m)
Volcano Alert Level: WATCH
Aviation Color Code: ORANGE
This report on the status of Kilauea volcanic activity, in addition to maps, photos, and webcam images (available using the menu bar above), was prepared by the USGS Hawaiian Volcano Observatory (HVO). Hawai`i Volcanoes National Park status can be found at http://www.nps.gov/havo/ or 985-6000. Hawai`i County Viewing Area status can be found at 961-8093.
Activity Summary for last 24 hours: There have been no significant changes. Sulfur dioxide emission rates from the Halema`uma`u and the Pu`u `O`o vents remain high although the emissions from Pu`u `O`o have been decreasing since August. Tephra production from the Halema`uma`u vent remains small. At the east rift eruption site, lava flows through tubes to the ocean; surface flows are active on the pali.
Last 24 hours at Kilauea summit: Vent glow was not often visible and too weak to be recorded by the webcam overnight. This morning, the gas plume arcs up and over the crater rim and is moving about 300 m (1,000 ft) above and southwestward over the Ka`u Desert. GOES-WEST imagery shows the plume continuing SW inland of the coast.
Tephra probably continues but sample collection will resume on Monday.
Sulfur dioxide emission rates remain elevated and variable. The most recent average measurement was 500 tonnes/day on October 31, compared to the 2003-2007 average rate of 140 tonnes/day.
The network of tiltmeters within Kilauea caldera recorded very weak inward tilt. The GPS receiver networks (less sensitive than tiltmeters) recorded weak contraction (barely 1 cm per month).
Seismic activity continued at low levels focused on the south caldera; tremor levels remain at low values. A total of 12 earthquakes were located beneath Kilauea or nearby, including 7 beneath the south caldera and 3 on south flank faults (including a preliminary magnitude-2.8 earthquake at 7:01 am), with the number of RB2S2BL earthquakes remaining slightly elevated at values around 50-60/day.
Last 24 hours at the middle east rift zone vents and flow field: Magma continues to degas through Pu`u `O`o Crater. The most recent sulfur dioxide measurement of 1,200 tonnes/day on October 30 is below the 2003-2007 average of about 1,700 tonnes/day for this vent; Pu`u `O`o emission rates have been slowly declining since early August. No incandescence was observed within the crater overnight.
The tiltmeter on the north side of Pu`u `O`o recorded minor oscillations and weak tilting inward toward the crater. GPS stations spanning the crater (less sensitive than tiltmeters) recorded about 7 cm of contraction over the past 3 months but at a decreased rate since 10/27. Seismic tremor levels near Pu`u `O`o and the TEB vent remain at low values.
Lava from the TEB vent and the rootless shield complex flows through tubes to the ocean. Yesterday's MODIS images showed thermal anomalies within the abandoned Royal Gardens subdivision, indicating continuing surface flow activity on the pali, and a distinct steam plume from the ocean entry at 1:25 pm. CD officials confirmed the pali surface flow activity last night and reported a continuing steam plume with some explosive activity from the ocean entry. A single spot from the TEB vent was the only incandescence seen overnight in the area from the east rift eruption site to the top of the pali above the abandoned subdivision. GOES-WEST imagery again recorded persistent thermal anomalies suggesting continuing surface flows overnight. This morning, the imagery shows a small steam plume from the ocean entry moving out to sea at 7 am.
Definitions of terms used in the update:
FLIR: Forward Looking InfraRed, a camera which directly images heat rather than visible light. If volcanic fume is not too rich in water vapor, a FLIR can see through it to image hot surfaces.
pali: Hawaiian word for cliff or steep incline. In the context of the TEB flow field, 'pali' usually refers to Pulama pali that bisects the abandoned Royal Gardens subdivision.
CD: Hawai`i County Civil Defense
DOH air quality monitoring: see Hawai`i State Department of Health Air Quality website http://hawaii.gov/doh/air-quality/index.html .
bomb: lava fragment ejected into the air while molten acquiring aerodynamic shapes in flight; the term is restricted to pieces larger than 6.4 cm (2.5 in.). See http://volcanoes.usgs.gov/Products/Pglossary/bomb.html
hybrid, or explosion, seismic signals: complex earthquakes that are a hybrid of different signals. They start as a high frequency earthquake, similar to typical rock-breaking or rock fall events, that transitions to very long, 20-30 second, period (VLP) oscillations that continue for several minutes. At HVO, we observed these signals with the four small Halema`uma`u explosive eruptions in March, April, and August 2008. Several more similar signals, some as strong as the explosion signals associated with the four explosive eruptions, have been recorded without obvious evidenceof surface eruption such as rock fragments or other debris.
MODIS satellite: a NASA satellite pair, Aqua and Terra, which passes over Hawai`i twice a day. During daylight hours, the images are taken at about 11 am and 2 pm H.s.t. This imagery can be viewed about 3-5 hours after acquisition at http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=AERONET_Mauna_Loa.
GOES-WEST satellite: a geostationary NOAA satellite used most often for weather tracking. Images are typically acquired every 15 minutes. The loop http://www.ssd.noaa.gov/VAAC/kilauea/sloop-vis.html is posted by the Washington DC Volcanic Ash Advisory Center for the purpose of tracking emissions from Hawai`i volcanoes. The imagery automatically switches from infrared at night to visual during the day. Recently, it has been useful for tracking volcanic gas emissions from Halema`uma`u, Pu`u `O`o, and the Waikupanaha ocean entry during the day and hot lava flows at night.
Volcano Watch: weekly newspaper-like article written by HVO scientists on a volcano topic of interest. These articles are usually printed in the Sunday editions of the Hawai`i Island newspapers Hawaii Tribune Herald and West Hawaii Today. More than 800 of these articles have been written and are archived on the HVO website (menu at the bottom of the homepage hvo.wr.usgs.gov).
VLP seismic tremor: seismic tremor is continuous ground vibrations simultaneously at many different frequencies. VLP is a very long period or very low frequency component which, at the Halema`uma`u vent, has a period of 20-30 seconds or a frequency of 0.03-0.05 cycles per second (Hertz or Hz).
RB2S2BL earthquakes: earthquakes that were recorded but too small to be located. These quakes have magnitudes less than 1.7 and may only be recorded on one or two seismometers. Recording at a minimum of 4 seismometer sites is required to locate an earthquake.
wink: an abrupt shutting off of incandescence at a vent lasting for several minutes. At the Halema`uma`u vent, winks usually start with or immediately follow a small, local earthquake. The diminishment of incandescence is due to the plume changing from translucent to opaque with rock dust.
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
microradian: a measure of angle equivalent to 0.000057 degrees.
ppm: parts-per-million; 10,000 ppm = 1 %.
littoral cone: usually small cones built near active ocean entries; the cones are constructed of tephra from steam explosions that are sometimes produced when 1,150 degree C lava enters the 25 degree C ocean.
incandescence: the production of visible light from a hot surface. The color of the light is related to the temperature of the surface. Some surfaces can display dull red incandescence at temperatures as low as 430 degrees Centigrade (806 degrees Fahrenheit). By contrast, molten lava displays bright orange to orange-yellow light from surfaces that are hotter than 900 degrees C (1,650 degrees F).
tephra: all material deposited by fallout from an eruption-related plume, regardless of size.
ash: tephra less than 2 mm (5/64 inches) in size.
TEB: Thanksgiving Eve Breakout, the designation used for lava flows that started with a breakout on November 21, 2007.
DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a volcanic event of uncertain significance. DI events are recorded by tiltmeters at Kilauea summit as an abrupt deflation of up to a few microradians in magnitude lasting several hours to 2-3 days followed by an abrupt inflation of approximately equal magnitude. The tilt events are usually accompanied by an increase in summit tremor during the deflation phase. A careful analysis of these events suggests that they may be related to changes in magma supply to a storage reservoir at less than 1 km depth, just east of Halema`uma`u crater. Usually, though not always, these changes propagate through the magma conduit from the summit to the eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by 1-2 hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
Maps, photos, webcam views, and other information about Kilauea Volcano are available at http://volcano.wr.usgs.gov/kilaueastatus.php. A daily update summary is available by phone at (808) 967-8862.
A map with details of earthquakes located within the past two weeks can be found at http://tux.wr.usgs.gov/
A definition of alert levels can be found at http://volcanoes.usgs.gov/2006/warnschemes.html
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Saturday, November 1, 2008 08:18 HST (Saturday, November 1, 2008 18:18 UTC)
KILAUEA VOLCANO (CAVW#1302-01-)
19.42°N 155.29°W, Summit Elevation 4091 ft (1247 m)
Volcano Alert Level: WATCH
Aviation Color Code: ORANGE
This report on the status of Kilauea volcanic activity, in addition to maps, photos, and webcam images (available using the menu bar above), was prepared by the USGS Hawaiian Volcano Observatory (HVO). Hawai`i Volcanoes National Park status can be found at http://www.nps.gov/havo/ or 985-6000. Hawai`i County Viewing Area status can be found at 961-8093.
Activity Summary for last 24 hours: There have been no significant changes. Sulfur dioxide emission rates from the Halema`uma`u and the Pu`u `O`o vents remain high although the emissions from Pu`u `O`o have been decreasing since August. Tephra production from the Halema`uma`u vent remains small. At the east rift eruption site, lava flows through tubes to the ocean; surface flows are active on the pali.
Last 24 hours at Kilauea summit: Vent glow was not often visible and too weak to be recorded by the webcam overnight. This morning, the gas plume arcs up and over the crater rim and is moving low and southsouthwestward over the Ka`u Desert. GOES-WEST imagery shows the plume continuing south before turning SW just inland of the coast.
Tephra probably continues but sample collection will resume on Monday.
Sulfur dioxide emission rates remain elevated and variable. The most recent average measurement was 500 tonnes/day on October 31, compared to the 2003-2007 average rate of 140 tonnes/day.
The network of tiltmeters within Kilauea caldera recorded very weak inward tilt. The GPS receiver networks (less sensitive than tiltmeters) recorded weak contraction (barely 1 cm per month).
Seismic activity continued to be focused on the south caldera; tremor levels remain at low but slowly increasing values. A total of 10 earthquakes were located beneath Kilauea or nearby, including 4 beneath the south caldera and 2 on south flank faults, with the number of RB2S2BL earthquakes remaining slightly elevated at values around 50/day.
Last 24 hours at the middle east rift zone vents and flow field: Magma continues to degas through Pu`u `O`o Crater. The most recent sulfur dioxide measurement of 1,200 tonnes/day on October 30 is below the 2003-2007 average of about 1,700 tonnes/day for this vent; Pu`u `O`o emission rates have been slowly declining since early August. No incandescence was observed within the crater overnight.
Pu`u `O`o may be slowly inflating. The tiltmeter on the north side of Pu`u `O`o recorded minor oscillations and no other significant tilting. GPS stations spanning the crater (less sensitive than tiltmeters) recorded a slight extension since 10/26. Seismic tremor levels near Pu`u `O`o and the TEB vent remain at low values; the tremor near the TEB vent increased about 40% around 5 am this morning.
Lava from the TEB vent and the rootless shield complex flows through tubes downslope toward the ocean. Yesterday's MODIS images showed thermal anomalies within the abandoned Royal Gardens subdivision indicating continuing surface flow activity on the pali. CD officials confirmed the pali surface flows last night and reported a large steam plume with some explosive activity from the ocean entry. No incandescence was seen overnight in the area from the east rift eruption site to the top of the pali above the abandoned subdivision. GOES-WEST imagery again recorded persistent thermal anomalies suggesting continuing surface flows through this morning. CD officials initially reported no ocean entry plume this morning but later were able to see a small one.
Definitions of terms used in the update:
FLIR: Forward Looking InfraRed, a camera which directly images heat rather than visible light. If volcanic fume is not too rich in water vapor, a FLIR can see through it to image hot surfaces.
pali: Hawaiian word for cliff or steep incline. In the context of the TEB flow field, 'pali' usually refers to Pulama pali that bisects the abandoned Royal Gardens subdivision.
CD: Hawai`i County Civil Defense
DOH air quality monitoring: see Hawai`i State Department of Health Air Quality website http://hawaii.gov/doh/air-quality/index.html .
bomb: lava fragment ejected into the air while molten acquiring aerodynamic shapes in flight; the term is restricted to pieces larger than 6.4 cm (2.5 in.). See http://volcanoes.usgs.gov/Products/Pglossary/bomb.html
hybrid, or explosion, seismic signals: complex earthquakes that are a hybrid of different signals. They start as a high frequency earthquake, similar to typical rock-breaking or rock fall events, that transitions to very long, 20-30 second, period (VLP) oscillations that continue for several minutes. At HVO, we observed these signals with the four small Halema`uma`u explosive eruptions in March, April, and August 2008. Several more similar signals, some as strong as the explosion signals associated with the four explosive eruptions, have been recorded without obvious evidenceof surface eruption such as rock fragments or other debris.
MODIS satellite: a NASA satellite pair, Aqua and Terra, which passes over Hawai`i twice a day. During daylight hours, the images are taken at about 11 am and 2 pm H.s.t. This imagery can be viewed about 3-5 hours after acquisition at http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=AERONET_Mauna_Loa.
GOES-WEST satellite: a geostationary NOAA satellite used most often for weather tracking. Images are typically acquired every 15 minutes. The loop http://www.ssd.noaa.gov/VAAC/kilauea/sloop-vis.html is posted by the Washington DC Volcanic Ash Advisory Center for the purpose of tracking emissions from Hawai`i volcanoes. The imagery automatically switches from infrared at night to visual during the day. Recently, it has been useful for tracking volcanic gas emissions from Halema`uma`u, Pu`u `O`o, and the Waikupanaha ocean entry during the day and hot lava flows at night.
Volcano Watch: weekly newspaper-like article written by HVO scientists on a volcano topic of interest. These articles are usually printed in the Sunday editions of the Hawai`i Island newspapers Hawaii Tribune Herald and West Hawaii Today. More than 800 of these articles have been written and are archived on the HVO website (menu at the bottom of the homepage hvo.wr.usgs.gov).
VLP seismic tremor: seismic tremor is continuous ground vibrations simultaneously at many different frequencies. VLP is a very long period or very low frequency component which, at the Halema`uma`u vent, has a period of 20-30 seconds or a frequency of 0.03-0.05 cycles per second (Hertz or Hz).
RB2S2BL earthquakes: earthquakes that were recorded but too small to be located. These quakes have magnitudes less than 1.7 and may only be recorded on one or two seismometers. Recording at a minimum of 4 seismometer sites is required to locate an earthquake.
wink: an abrupt shutting off of incandescence at a vent lasting for several minutes. At the Halema`uma`u vent, winks usually start with or immediately follow a small, local earthquake. The diminishment of incandescence is due to the plume changing from translucent to opaque with rock dust.
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
microradian: a measure of angle equivalent to 0.000057 degrees.
ppm: parts-per-million; 10,000 ppm = 1 %.
littoral cone: usually small cones built near active ocean entries; the cones are constructed of tephra from steam explosions that are sometimes produced when 1,150 degree C lava enters the 25 degree C ocean.
incandescence: the production of visible light from a hot surface. The color of the light is related to the temperature of the surface. Some surfaces can display dull red incandescence at temperatures as low as 430 degrees Centigrade (806 degrees Fahrenheit). By contrast, molten lava displays bright orange to orange-yellow light from surfaces that are hotter than 900 degrees C (1,650 degrees F).
tephra: all material deposited by fallout from an eruption-related plume, regardless of size.
ash: tephra less than 2 mm (5/64 inches) in size.
TEB: Thanksgiving Eve Breakout, the designation used for lava flows that started with a breakout on November 21, 2007.
DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a volcanic event of uncertain significance. DI events are recorded by tiltmeters at Kilauea summit as an abrupt deflation of up to a few microradians in magnitude lasting several hours to 2-3 days followed by an abrupt inflation of approximately equal magnitude. The tilt events are usually accompanied by an increase in summit tremor during the deflation phase. A careful analysis of these events suggests that they may be related to changes in magma supply to a storage reservoir at less than 1 km depth, just east of Halema`uma`u crater. Usually, though not always, these changes propagate through the magma conduit from the summit to the eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by 1-2 hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
Maps, photos, webcam views, and other information about Kilauea Volcano are available at http://volcano.wr.usgs.gov/kilaueastatus.php. A daily update summary is available by phone at (808) 967-8862.
A map with details of earthquakes located within the past two weeks can be found at http://tux.wr.usgs.gov/
A definition of alert levels can be found at http://volcanoes.usgs.gov/2006/warnschemes.html
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Saturday, November 1, 2008 07:59 HST (Saturday, November 1, 2008 17:59 UTC)
KILAUEA VOLCANO (CAVW#1302-01-)
19.42°N 155.29°W, Summit Elevation 4091 ft (1247 m)
Volcano Alert Level: WATCH
Aviation Color Code: ORANGE
This report on the status of Kilauea volcanic activity, in addition to maps, photos, and webcam images (available using the menu bar above), was prepared by the USGS Hawaiian Volcano Observatory (HVO). Hawai`i Volcanoes National Park status can be found at http://www.nps.gov/havo/ or 985-6000. Hawai`i County Viewing Area status can be found at 961-8093.
Activity Summary for last 24 hours: There have been no significant changes. Sulfur dioxide emission rates from the Halema`uma`u and the Pu`u `O`o vents remain high although the emissions from Pu`u `O`o have been decreasing since August. Tephra production from the Halema`uma`u vent remains small. At the east rift eruption site, lava flows through tubes toward the ocean; surface flows are active on the pali.
Last 24 hours at Kilauea summit: Vent glow was not often visible and too weak to be recorded by the webcam overnight. This morning, the gas plume arcs up and over the crater rim and is moving low and southsouthwestward over the Ka`u Desert. GOES-WEST imagery shows the plume continuing south before turning SW just inland of the coast.
Tephra probably continues but sample collection will resume on Monday.
Sulfur dioxide emission rates remain elevated and variable. The most recent average measurement was 500 tonnes/day on October 31, compared to the 2003-2007 average rate of 140 tonnes/day.
The network of tiltmeters within Kilauea caldera recorded very weak inward tilt. The GPS receiver networks (less sensitive than tiltmeters) recorded weak contraction (barely 1 cm per month).
Seismic activity continued to be focused on the south caldera; tremor levels remain at low but slowly increasing values. A total of 10 earthquakes were located beneath Kilauea or nearby, including 4 beneath the south caldera and 2 on south flank faults, with the number of RB2S2BL earthquakes remaining slightly elevated at values around 50/day.
Last 24 hours at the middle east rift zone vents and flow field: Magma continues to degas through Pu`u `O`o Crater. The most recent sulfur dioxide measurement of 1,200 tonnes/day on October 30 is below the 2003-2007 average of about 1,700 tonnes/day for this vent; Pu`u `O`o emission rates have been slowly declining since early August. No incandescence was observed within the crater overnight.
Pu`u `O`o may be slowly inflating. The tiltmeter on the north side of Pu`u `O`o recorded minor oscillations and no other significant tilting. GPS stations spanning the crater (less sensitive than tiltmeters) recorded a slight extension since 10/26. Seismic tremor levels near Pu`u `O`o and the TEB vent remain at low values; the tremor near the TEB vent increased about 40% around 5 am this morning.
Lava from the TEB vent and the rootless shield complex flows through tubes downslope toward the ocean. Yesterday's MODIS images showed thermal anomalies within the abandoned Royal Gardens subdivision indicating continuing surface flow activity on the pali. CD officials confirmed the pali surface flows last night and reported a large steam plume with some explosive activity from the ocean entry. No incandescence was seen overnight in the area from the east rift eruption site to the top of the pali above the abandoned subdivision. GOES-WEST imagery again recorded persistent thermal anomalies suggesting continuing surface flows through this morning but CD officials and the GOES-WEST imagery both indicate there is either no ocean entry plume or it is greatly diminished at 7 am.
Definitions of terms used in the update:
FLIR: Forward Looking InfraRed, a camera which directly images heat rather than visible light. If volcanic fume is not too rich in water vapor, a FLIR can see through it to image hot surfaces.
pali: Hawaiian word for cliff or steep incline. In the context of the TEB flow field, 'pali' usually refers to Pulama pali that bisects the abandoned Royal Gardens subdivision.
CD: Hawai`i County Civil Defense
DOH air quality monitoring: see Hawai`i State Department of Health Air Quality website http://hawaii.gov/doh/air-quality/index.html .
bomb: lava fragment ejected into the air while molten acquiring aerodynamic shapes in flight; the term is restricted to pieces larger than 6.4 cm (2.5 in.). See http://volcanoes.usgs.gov/Products/Pglossary/bomb.html
hybrid, or explosion, seismic signals: complex earthquakes that are a hybrid of different signals. They start as a high frequency earthquake, similar to typical rock-breaking or rock fall events, that transitions to very long, 20-30 second, period (VLP) oscillations that continue for several minutes. At HVO, we observed these signals with the four small Halema`uma`u explosive eruptions in March, April, and August 2008. Several more similar signals, some as strong as the explosion signals associated with the four explosive eruptions, have been recorded without obvious evidenceof surface eruption such as rock fragments or other debris.
MODIS satellite: a NASA satellite pair, Aqua and Terra, which passes over Hawai`i twice a day. During daylight hours, the images are taken at about 11 am and 2 pm H.s.t. This imagery can be viewed about 3-5 hours after acquisition at http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=AERONET_Mauna_Loa.
GOES-WEST satellite: a geostationary NOAA satellite used most often for weather tracking. Images are typically acquired every 15 minutes. The loop http://www.ssd.noaa.gov/VAAC/kilauea/sloop-vis.html is posted by the Washington DC Volcanic Ash Advisory Center for the purpose of tracking emissions from Hawai`i volcanoes. The imagery automatically switches from infrared at night to visual during the day. Recently, it has been useful for tracking volcanic gas emissions from Halema`uma`u, Pu`u `O`o, and the Waikupanaha ocean entry during the day and hot lava flows at night.
Volcano Watch: weekly newspaper-like article written by HVO scientists on a volcano topic of interest. These articles are usually printed in the Sunday editions of the Hawai`i Island newspapers Hawaii Tribune Herald and West Hawaii Today. More than 800 of these articles have been written and are archived on the HVO website (menu at the bottom of the homepage hvo.wr.usgs.gov).
VLP seismic tremor: seismic tremor is continuous ground vibrations simultaneously at many different frequencies. VLP is a very long period or very low frequency component which, at the Halema`uma`u vent, has a period of 20-30 seconds or a frequency of 0.03-0.05 cycles per second (Hertz or Hz).
RB2S2BL earthquakes: earthquakes that were recorded but too small to be located. These quakes have magnitudes less than 1.7 and may only be recorded on one or two seismometers. Recording at a minimum of 4 seismometer sites is required to locate an earthquake.
wink: an abrupt shutting off of incandescence at a vent lasting for several minutes. At the Halema`uma`u vent, winks usually start with or immediately follow a small, local earthquake. The diminishment of incandescence is due to the plume changing from translucent to opaque with rock dust.
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
microradian: a measure of angle equivalent to 0.000057 degrees.
ppm: parts-per-million; 10,000 ppm = 1 %.
littoral cone: usually small cones built near active ocean entries; the cones are constructed of tephra from steam explosions that are sometimes produced when 1,150 degree C lava enters the 25 degree C ocean.
incandescence: the production of visible light from a hot surface. The color of the light is related to the temperature of the surface. Some surfaces can display dull red incandescence at temperatures as low as 430 degrees Centigrade (806 degrees Fahrenheit). By contrast, molten lava displays bright orange to orange-yellow light from surfaces that are hotter than 900 degrees C (1,650 degrees F).
tephra: all material deposited by fallout from an eruption-related plume, regardless of size.
ash: tephra less than 2 mm (5/64 inches) in size.
TEB: Thanksgiving Eve Breakout, the designation used for lava flows that started with a breakout on November 21, 2007.
DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a volcanic event of uncertain significance. DI events are recorded by tiltmeters at Kilauea summit as an abrupt deflation of up to a few microradians in magnitude lasting several hours to 2-3 days followed by an abrupt inflation of approximately equal magnitude. The tilt events are usually accompanied by an increase in summit tremor during the deflation phase. A careful analysis of these events suggests that they may be related to changes in magma supply to a storage reservoir at less than 1 km depth, just east of Halema`uma`u crater. Usually, though not always, these changes propagate through the magma conduit from the summit to the eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by 1-2 hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
Maps, photos, webcam views, and other information about Kilauea Volcano are available at http://volcano.wr.usgs.gov/kilaueastatus.php. A daily update summary is available by phone at (808) 967-8862.
A map with details of earthquakes located within the past two weeks can be found at http://tux.wr.usgs.gov/
A definition of alert levels can be found at http://volcanoes.usgs.gov/2006/warnschemes.html
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Friday, October 31, 2008 07:45 HST (Friday, October 31, 2008 17:45 UTC)
KILAUEA VOLCANO (CAVW#1302-01-)
19.42°N 155.29°W, Summit Elevation 4091 ft (1247 m)
Volcano Alert Level: WATCH
Aviation Color Code: ORANGE
This report on the status of Kilauea volcanic activity, in addition to maps, photos, and webcam images (available using the menu bar above), was prepared by the USGS Hawaiian Volcano Observatory (HVO). Hawai`i Volcanoes National Park status can be found at http://www.nps.gov/havo/ or 985-6000. Hawai`i County Viewing Area status can be found at 961-8093.
Activity Summary for last 24 hours: There have been no significant changes. Sulfur dioxide emission rates from the Halema`uma`u and the Pu`u `O`o vents remain high although the emissions from Pu`u `O`o have been decreasing since August. Tephra production from the Halema`uma`u vent remains small. At the east rift eruption site, lava again flows through tubes to the ocean; surface flows are active on the pali.
Last 24 hours at Kilauea summit: The plume was briefly turned an ashy brown just after noon. Vent glow was too weak to be recorded by the webcam overnight. This morning, the gas plume arcs up and over the crater rim and is moving low and southwestward over the Ka`u Desert. GOES-WEST imagery shows the plume continuing SSW to the coast at 6:30 am this morning.
Small amounts of tephra continued to be produced, the collections continue to consist mostly of glassy spatter as has been the case since early September. During the collection routine, the same distant surf could be heard from the vent with a few rock clatters and at least one boom thrown into the mix.
Sulfur dioxide emission rates remain elevated and variable. The most recent average measurement was 700 tonnes/day on October 30, compared to the 2003-2007 average rate of 140 tonnes/day.
The network of tiltmeters within Kilauea caldera recorded no coherent tilting. The GPS receiver networks (less sensitive than tiltmeters) recorded weak contraction.
Seismic activity continued to be focused on the south caldera; tremor levels remain at low values. A total of 12 earthquakes were located beneath Kilauea or nearby, including 5 beneath the south caldera, with the number of RB2S2BL earthquakes remaining slightly elevated at values around 50/day.
Last 24 hours at the middle east rift zone vents and flow field: Magma continues to degas through Pu`u `O`o Crater. The most recent sulfur dioxide measurement of 1,200 tonnes/day on October 30 is below the 2003-2007 average of about 1,700 tonnes/day for this vent; Pu`u `O`o emission rates have been slowly declining since early August. No incandescence was observed within the crater overnight.
Pu`u `O`o continues to deflate/collapse. The tiltmeter on the north side of Pu`u `O`o recorded no significant changes beyond a rain-induced signal this morning. GPS stations spanning the crater (less sensitive than tiltmeters) recorded no significant contraction or extension. Seismic tremor levels near Pu`u `O`o and the TEB vent remain at low values; the tremor near the TEB vent has become variable in strength.
Lava from the TEB vent and the rootless shield complex again flows through tubes to the ocean. Yesterday evening, CD officials reported a large plume but little incandescence from the Waikupanaha ocean entry; surface flows were still active on the pali. No incandescence was seen from the TEB vent overnight. GOES-WEST imagery recorded persistent thermal anomalies suggesting continuing surface flows. This morning, CD officials that the ocean entry is still producing a large steam plume.
Definitions of terms used in the update:
FLIR: Forward Looking InfraRed, a camera which directly images heat rather than visible light. If volcanic fume is not too rich in water vapor, a FLIR can see through it to image hot surfaces.
pali: Hawaiian word for cliff or steep incline. In the context of the TEB flow field, 'pali' usually refers to Pulama pali that bisects the abandoned Royal Gardens subdivision.
CD: Hawai`i County Civil Defense
DOH air quality monitoring: see Hawai`i State Department of Health Air Quality website http://hawaii.gov/doh/air-quality/index.html .
bomb: lava fragment ejected into the air while molten acquiring aerodynamic shapes in flight; the term is restricted to pieces larger than 6.4 cm (2.5 in.). See http://volcanoes.usgs.gov/Products/Pglossary/bomb.html
hybrid, or explosion, seismic signals: complex earthquakes that are a hybrid of different signals. They start as a high frequency earthquake, similar to typical rock-breaking or rock fall events, that transitions to very long, 20-30 second, period (VLP) oscillations that continue for several minutes. At HVO, we observed these signals with the four small Halema`uma`u explosive eruptions in March, April, and August 2008. Several more similar signals, some as strong as the explosion signals associated with the four explosive eruptions, have been recorded without obvious evidenceof surface eruption such as rock fragments or other debris.
MODIS satellite: a NASA satellite pair, Aqua and Terra, which passes over Hawai`i twice a day. During daylight hours, the images are taken at about 11 am and 2 pm H.s.t. This imagery can be viewed about 3-5 hours after acquisition at http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=AERONET_Mauna_Loa.
GOES-WEST satellite: a geostationary NOAA satellite used most often for weather tracking. Images are typically acquired every 15 minutes. The loop http://www.ssd.noaa.gov/VAAC/kilauea/sloop-vis.html is posted by the Washington DC Volcanic Ash Advisory Center for the purpose of tracking emissions from Hawai`i volcanoes. The imagery automatically switches from infrared at night to visual during the day. Recently, it has been useful for tracking volcanic gas emissions from Halema`uma`u, Pu`u `O`o, and the Waikupanaha ocean entry during the day and hot lava flows at night.
Volcano Watch: weekly newspaper-like article written by HVO scientists on a volcano topic of interest. These articles are usually printed in the Sunday editions of the Hawai`i Island newspapers Hawaii Tribune Herald and West Hawaii Today. More than 800 of these articles have been written and are archived on the HVO website (menu at the bottom of the homepage hvo.wr.usgs.gov).
VLP seismic tremor: seismic tremor is continuous ground vibrations simultaneously at many different frequencies. VLP is a very long period or very low frequency component which, at the Halema`uma`u vent, has a period of 20-30 seconds or a frequency of 0.03-0.05 cycles per second (Hertz or Hz).
RB2S2BL earthquakes: earthquakes that were recorded but too small to be located. These quakes have magnitudes less than 1.7 and may only be recorded on one or two seismometers. Recording at a minimum of 4 seismometer sites is required to locate an earthquake.
wink: an abrupt shutting off of incandescence at a vent lasting for several minutes. At the Halema`uma`u vent, winks usually start with or immediately follow a small, local earthquake. The diminishment of incandescence is due to the plume changing from translucent to opaque with rock dust.
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
microradian: a measure of angle equivalent to 0.000057 degrees.
ppm: parts-per-million; 10,000 ppm = 1 %.
littoral cone: usually small cones built near active ocean entries; the cones are constructed of tephra from steam explosions that are sometimes produced when 1,150 degree C lava enters the 25 degree C ocean.
incandescence: the production of visible light from a hot surface. The color of the light is related to the temperature of the surface. Some surfaces can display dull red incandescence at temperatures as low as 430 degrees Centigrade (806 degrees Fahrenheit). By contrast, molten lava displays bright orange to orange-yellow light from surfaces that are hotter than 900 degrees C (1,650 degrees F).
tephra: all material deposited by fallout from an eruption-related plume, regardless of size.
ash: tephra less than 2 mm (5/64 inches) in size.
TEB: Thanksgiving Eve Breakout, the designation used for lava flows that started with a breakout on November 21, 2007.
DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a volcanic event of uncertain significance. DI events are recorded by tiltmeters at Kilauea summit as an abrupt deflation of up to a few microradians in magnitude lasting several hours to 2-3 days followed by an abrupt inflation of approximately equal magnitude. The tilt events are usually accompanied by an increase in summit tremor during the deflation phase. A careful analysis of these events suggests that they may be related to changes in magma supply to a storage reservoir at less than 1 km depth, just east of Halema`uma`u crater. Usually, though not always, these changes propagate through the magma conduit from the summit to the eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by 1-2 hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
Maps, photos, webcam views, and other information about Kilauea Volcano are available at http://volcano.wr.usgs.gov/kilaueastatus.php. A daily update summary is available by phone at (808) 967-8862.
A map with details of earthquakes located within the past two weeks can be found at http://tux.wr.usgs.gov/
A definition of alert levels can be found at http://volcanoes.usgs.gov/2006/warnschemes.html
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Thursday, October 30, 2008 07:49 HST (Thursday, October 30, 2008 17:49 UTC)
KILAUEA VOLCANO (CAVW#1302-01-)
19.42°N 155.29°W, Summit Elevation 4091 ft (1247 m)
Volcano Alert Level: WATCH
Aviation Color Code: ORANGE
This report on the status of Kilauea volcanic activity, in addition to maps, photos, and webcam images (available using the menu bar above), was prepared by the USGS Hawaiian Volcano Observatory (HVO). Hawai`i Volcanoes National Park status can be found at http://www.nps.gov/havo/ or 985-6000. Hawai`i County Viewing Area status can be found at 961-8093.
Activity Summary for last 24 hours: There have been no significant changes. Sulfur dioxide emission rates from the Halema`uma`u and the Pu`u `O`o vents remain high although the emissions from Pu`u `O`o have been decreasing since August. Tephra production from the Halema`uma`u vent remains small. At the east rift eruption site, lava again flows through tubes to the ocean; surface flows are active on the pali.
Last 24 hours at Kilauea summit: The returning trade winds were able to clear summit air by afternoon. Vent glow was too weak to be recorded by the webcam overnight. This morning, the gas plume arcs up and over the crater rim and is moving low and southwestward over the Ka`u Desert. GOES-WEST imagery shows the plume continuing SSW to the coast at 6:45 am this morning.
Small amounts of tephra continued to be produced, the collections continue to consist mostly of glassy spatter as has been the case since early September. During the collection routine, the same distant surf could be heard from the vent.
Sulfur dioxide emission rates remain elevated and variable. The most recent average measurement was 700 tonnes/day on October 29, compared to the 2003-2007 average rate of 140 tonnes/day.
The summit caldera is deflating. The network of tiltmeters within Kilauea caldera resumed recording weak deflation. The GPS receiver networks (less sensitive than tiltmeters) recorded contraction.
Seismic activity continued to be focused on the south caldera; tremor levels remain at low values. A total of 11 earthquakes were located beneath Kilauea or nearby, including 8 beneath the south caldera and 2 on south flank faults, with the number of RB2S2BL earthquakes remaining slightly elevated at values around 60/day.
Last 24 hours at the middle east rift zone vents and flow field: Magma continues to degas through Pu`u `O`o Crater. The most recent sulfur dioxide measurement of 1,100 tonnes/day on October 24 is below the 2005-2007 average of about 2,000 tonnes/day for this vent; Pu`u `O`o emission rates have been slowly declining since early August. No incandescence was observed within the crater overnight.
Pu`u `O`o continues to deflate/collapse. The tiltmeter on the north side of Pu`u `O`o recorded ground tilting inward toward the crater. GPS stations spanning the crater (less sensitive than tiltmeters) recorded no significant contraction or extension. Seismic tremor levels near Pu`u `O`o and the TEB vent remain at low values; the tremor near the TEB vent reached a peak yesterday and is currently decreasing in value.
Lava from the TEB vent and the rootless shield complex again flows through tubes to the ocean. No incandescence was seen from the TEB vent overnight. GOES-WEST imagery recorded persistent thermal anomalies suggesting continuing surface flows. this morning, CD officials confirmed active surface flows within the abandoned Royal Gardens subdivision extending out into the coastal plain. The ocean entry has become wider and is still going strong.
Definitions of terms used in the update:
FLIR: Forward Looking InfraRed, a camera which directly images heat rather than visible light. If volcanic fume is not too rich in water vapor, a FLIR can see through it to image hot surfaces.
pali: Hawaiian word for cliff or steep incline. In the context of the TEB flow field, 'pali' usually refers to Pulama pali that bisects the abandoned Royal Gardens subdivision.
CD: Hawai`i County Civil Defense
DOH air quality monitoring: see Hawai`i State Department of Health Air Quality website http://hawaii.gov/doh/air-quality/index.html .
bomb: lava fragment ejected into the air while molten acquiring aerodynamic shapes in flight; the term is restricted to pieces larger than 6.4 cm (2.5 in.). See http://volcanoes.usgs.gov/Products/Pglossary/bomb.html
hybrid, or explosion, seismic signals: complex earthquakes that are a hybrid of different signals. They start as a high frequency earthquake, similar to typical rock-breaking or rock fall events, that transitions to very long, 20-30 second, period (VLP) oscillations that continue for several minutes. At HVO, we observed these signals with the four small Halema`uma`u explosive eruptions in March, April, and August 2008. Several more similar signals, some as strong as the explosion signals associated with the four explosive eruptions, have been recorded without obvious evidenceof surface eruption such as rock fragments or other debris.
MODIS satellite: a NASA satellite pair, Aqua and Terra, which passes over Hawai`i twice a day. During daylight hours, the images are taken at about 11 am and 2 pm H.s.t. This imagery can be viewed about 3-5 hours after acquisition at http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=AERONET_Mauna_Loa.
GOES-WEST satellite: a geostationary NOAA satellite used most often for weather tracking. Images are typically acquired every 15 minutes. The loop http://www.ssd.noaa.gov/VAAC/kilauea/sloop-vis.html is posted by the Washington DC Volcanic Ash Advisory Center for the purpose of tracking emissions from Hawai`i volcanoes. The imagery automatically switches from infrared at night to visual during the day. Recently, it has been useful for tracking volcanic gas emissions from Halema`uma`u, Pu`u `O`o, and the Waikupanaha ocean entry during the day and hot lava flows at night.
Volcano Watch: weekly newspaper-like article written by HVO scientists on a volcano topic of interest. These articles are usually printed in the Sunday editions of the Hawai`i Island newspapers Hawaii Tribune Herald and West Hawaii Today. More than 800 of these articles have been written and are archived on the HVO website (menu at the bottom of the homepage hvo.wr.usgs.gov).
VLP seismic tremor: seismic tremor is continuous ground vibrations simultaneously at many different frequencies. VLP is a very long period or very low frequency component which, at the Halema`uma`u vent, has a period of 20-30 seconds or a frequency of 0.03-0.05 cycles per second (Hertz or Hz).
RB2S2BL earthquakes: earthquakes that were recorded but too small to be located. These quakes have magnitudes less than 1.7 and may only be recorded on one or two seismometers. Recording at a minimum of 4 seismometer sites is required to locate an earthquake.
wink: an abrupt shutting off of incandescence at a vent lasting for several minutes. At the Halema`uma`u vent, winks usually start with or immediately follow a small, local earthquake. The diminishment of incandescence is due to the plume changing from translucent to opaque with rock dust.
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
microradian: a measure of angle equivalent to 0.000057 degrees.
ppm: parts-per-million; 10,000 ppm = 1 %.
littoral cone: usually small cones built near active ocean entries; the cones are constructed of tephra from steam explosions that are sometimes produced when 1,150 degree C lava enters the 25 degree C ocean.
incandescence: the production of visible light from a hot surface. The color of the light is related to the temperature of the surface. Some surfaces can display dull red incandescence at temperatures as low as 430 degrees Centigrade (806 degrees Fahrenheit). By contrast, molten lava displays bright orange to orange-yellow light from surfaces that are hotter than 900 degrees C (1,650 degrees F).
tephra: all material deposited by fallout from an eruption-related plume, regardless of size.
ash: tephra less than 2 mm (5/64 inches) in size.
TEB: Thanksgiving Eve Breakout, the designation used for lava flows that started with a breakout on November 21, 2007.
DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a volcanic event of uncertain significance. DI events are recorded by tiltmeters at Kilauea summit as an abrupt deflation of up to a few microradians in magnitude lasting several hours to 2-3 days followed by an abrupt inflation of approximately equal magnitude. The tilt events are usually accompanied by an increase in summit tremor during the deflation phase. A careful analysis of these events suggests that they may be related to changes in magma supply to a storage reservoir at less than 1 km depth, just east of Halema`uma`u crater. Usually, though not always, these changes propagate through the magma conduit from the summit to the eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by 1-2 hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
Maps, photos, webcam views, and other information about Kilauea Volcano are available at http://volcano.wr.usgs.gov/kilaueastatus.php. A daily update summary is available by phone at (808) 967-8862.
A map with details of earthquakes located within the past two weeks can be found at http://tux.wr.usgs.gov/
A definition of alert levels can be found at http://volcanoes.usgs.gov/2006/warnschemes.html
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Wednesday, October 29, 2008 07:21 HST (Wednesday, October 29, 2008 17:21 UTC)
KILAUEA VOLCANO (CAVW#1302-01-)
19.42°N 155.29°W, Summit Elevation 4091 ft (1247 m)
Volcano Alert Level: WATCH
Aviation Color Code: ORANGE
This report on the status of Kilauea volcanic activity, in addition to maps, photos, and webcam images (available using the menu bar above), was prepared by the USGS Hawaiian Volcano Observatory (HVO). Hawai`i Volcanoes National Park status can be found at http://www.nps.gov/havo/ or 985-6000. Hawai`i County Viewing Area status can be found at 961-8093.
Activity Summary for last 24 hours: Sulfur dioxide emission rates from the Halema`uma`u and the Pu`u `O`o vents remain high although the emissions from Pu`u `O`o have been decreasing since August. Tephra production from the Halema`uma`u vent remains small. At the east rift eruption site, lava again flows through tubes to the ocean; surface flows are active on the pali.
Last 24 hours at Kilauea summit: Weak winds produced exceptionally poor air quality yesterday for a few hours before and after noon. Vent glow was too weak to be recorded by the webcam overnight. This morning, returning trade winds are causing the gas plume to arc up and over the crater rim and move southwestward and low over the Ka`u Desert. GOES-WEST imagery shows the plume continuing SW along the coast.
Small amounts of tephra continued to be produced, the collections continue to consist mostly of glassy spatter as has been the case since early September. This morning's collection included 1-cm-(0.4 in)-sized spatter and Pele's hair. During the collection routine, the same distant surf and rolling rock sounds could be heard from the vent.
Sulfur dioxide emission rates remain elevated and variable. The most recent average measurement was 500 tonnes/day on October 24, compared to the 2003-2007 average rate of 140 tonnes/day. If the trade winds hold at moderate strength, we should be able to get new emission rate measurements.
The network of tiltmeters within Kilauea caldera recorded weak inflation since completion of the DI tilt event on Monday. The GPS receiver networks (less sensitive than tiltmeters) recorded small changes but no significant extension or contraction over the past two weeks.
Seismic activity continued to be focused on the south caldera; tremor levels remain at low values. A total of 21 earthquakes were located beneath Kilauea or nearby, including 9 beneath the south caldera and 5 on south flank faults, with the number of RB2S2BL earthquakes remaining slightly elevated at values around 60/day.
Last 24 hours at the middle east rift zone vents and flow field: Magma continues to degas through Pu`u `O`o Crater. The most recent sulfur dioxide measurement of 1,100 tonnes/day on October 24 is below the 2005-2007 average of about 2,000 tonnes/day for this vent; Pu`u `O`o emission rates have been slowly declining since early August. No incandescence was observed within the crater overnight.
Pu`u `O`o continues to deflate/collapse. The tiltmeter on the north side of Pu`u `O`o recorded no significant change since completion of the DI tilt event on Monday. GPS stations spanning the crater (less sensitive than tiltmeters) recorded weak contraction across the crater followed by weak extension mimicking the tilt through the recent DI tilt event. Seismic tremor levels near Pu`u `O`o and the TEB vent remain at low values with the tremor near the TEB vent increasing slightly since Monday.
Lava from the TEB vent and the rootless shield complex again flows through tubes to the ocean. CD officials reported a strong ocean plume with surface activity apparent through the abandoned Royal Gardens subdivision last night. Weak incandescence was again seen from the TEB vent overnight. GOES-WEST imagery recorded new thermal anomalies revealed after high altitude clouds cleared at 3 am consistent with the new surface flows. This morning, CD officials reported that the ocean entry is going strong.
Definitions of terms used in the update:
FLIR: Forward Looking InfraRed, a camera which directly images heat rather than visible light. If volcanic fume is not too rich in water vapor, a FLIR can see through it to image hot surfaces.
pali: Hawaiian word for cliff or steep incline. In the context of the TEB flow field, 'pali' usually refers to Pulama pali that bisects the abandoned Royal Gardens subdivision.
CD: Hawai`i County Civil Defense
DOH air quality monitoring: see Hawai`i State Department of Health Air Quality website http://hawaii.gov/doh/air-quality/index.html .
bomb: lava fragment ejected into the air while molten acquiring aerodynamic shapes in flight; the term is restricted to pieces larger than 6.4 cm (2.5 in.). See http://volcanoes.usgs.gov/Products/Pglossary/bomb.html
hybrid, or explosion, seismic signals: complex earthquakes that are a hybrid of different signals. They start as a high frequency earthquake, similar to typical rock-breaking or rock fall events, that transitions to very long, 20-30 second, period (VLP) oscillations that continue for several minutes. At HVO, we observed these signals with the four small Halema`uma`u explosive eruptions in March, April, and August 2008. Several more similar signals, some as strong as the explosion signals associated with the four explosive eruptions, have been recorded without obvious evidenceof surface eruption such as rock fragments or other debris.
MODIS satellite: a NASA satellite pair, Aqua and Terra, which passes over Hawai`i twice a day. During daylight hours, the images are taken at about 11 am and 2 pm H.s.t. This imagery can be viewed about 3-5 hours after acquisition at http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=AERONET_Mauna_Loa.
GOES-WEST satellite: a geostationary NOAA satellite used most often for weather tracking. Images are typically acquired every 15 minutes. The loop http://www.ssd.noaa.gov/VAAC/kilauea/sloop-vis.html is posted by the Washington DC Volcanic Ash Advisory Center for the purpose of tracking emissions from Hawai`i volcanoes. The imagery automatically switches from infrared at night to visual during the day. Recently, it has been useful for tracking volcanic gas emissions from Halema`uma`u, Pu`u `O`o, and the Waikupanaha ocean entry during the day and hot lava flows at night.
Volcano Watch: weekly newspaper-like article written by HVO scientists on a volcano topic of interest. These articles are usually printed in the Sunday editions of the Hawai`i Island newspapers Hawaii Tribune Herald and West Hawaii Today. More than 800 of these articles have been written and are archived on the HVO website (menu at the bottom of the homepage hvo.wr.usgs.gov).
VLP seismic tremor: seismic tremor is continuous ground vibrations simultaneously at many different frequencies. VLP is a very long period or very low frequency component which, at the Halema`uma`u vent, has a period of 20-30 seconds or a frequency of 0.03-0.05 cycles per second (Hertz or Hz).
RB2S2BL earthquakes: earthquakes that were recorded but too small to be located. These quakes have magnitudes less than 1.7 and may only be recorded on one or two seismometers. Recording at a minimum of 4 seismometer sites is required to locate an earthquake.
wink: an abrupt shutting off of incandescence at a vent lasting for several minutes. At the Halema`uma`u vent, winks usually start with or immediately follow a small, local earthquake. The diminishment of incandescence is due to the plume changing from translucent to opaque with rock dust.
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
microradian: a measure of angle equivalent to 0.000057 degrees.
ppm: parts-per-million; 10,000 ppm = 1 %.
littoral cone: usually small cones built near active ocean entries; the cones are constructed of tephra from steam explosions that are sometimes produced when 1,150 degree C lava enters the 25 degree C ocean.
incandescence: the production of visible light from a hot surface. The color of the light is related to the temperature of the surface. Some surfaces can display dull red incandescence at temperatures as low as 430 degrees Centigrade (806 degrees Fahrenheit). By contrast, molten lava displays bright orange to orange-yellow light from surfaces that are hotter than 900 degrees C (1,650 degrees F).
tephra: all material deposited by fallout from an eruption-related plume, regardless of size.
ash: tephra less than 2 mm (5/64 inches) in size.
TEB: Thanksgiving Eve Breakout, the designation used for lava flows that started with a breakout on November 21, 2007.
DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a volcanic event of uncertain significance. DI events are recorded by tiltmeters at Kilauea summit as an abrupt deflation of up to a few microradians in magnitude lasting several hours to 2-3 days followed by an abrupt inflation of approximately equal magnitude. The tilt events are usually accompanied by an increase in summit tremor during the deflation phase. A careful analysis of these events suggests that they may be related to changes in magma supply to a storage reservoir at less than 1 km depth, just east of Halema`uma`u crater. Usually, though not always, these changes propagate through the magma conduit from the summit to the eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by 1-2 hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
Maps, photos, webcam views, and other information about Kilauea Volcano are available at http://volcano.wr.usgs.gov/kilaueastatus.php. A daily update summary is available by phone at (808) 967-8862.
A map with details of earthquakes located within the past two weeks can be found at http://tux.wr.usgs.gov/
A definition of alert levels can be found at http://volcanoes.usgs.gov/2006/warnschemes.html
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Tuesday, October 28, 2008 07:47 HST (Tuesday, October 28, 2008 17:47 UTC)
KILAUEA VOLCANO (CAVW#1302-01-)
19.42°N 155.29°W, Summit Elevation 4091 ft (1247 m)
Volcano Alert Level: WATCH
Aviation Color Code: ORANGE
This report on the status of Kilauea volcanic activity, in addition to maps, photos, and webcam images (available using the menu bar above), was prepared by the USGS Hawaiian Volcano Observatory (HVO). Hawai`i Volcanoes National Park status can be found at http://www.nps.gov/havo/ or 985-6000. Hawai`i County Viewing Area status can be found at 961-8093.
Activity Summary for last 24 hours: The final inflation started at Pu`u `O`o around 11:15 am yesterday completing the DI tilt event sequence. Sulfur dioxide emission rates from the Halema`uma`u and the Pu`u `O`o vents remain high although the emissions from Pu`u `O`o have been decreasing since August. Tephra production from the Halema`uma`u vent remains small. At the east rift eruption site, lava again flows through tubes to the ocean.
Last 24 hours at Kilauea summit: Weak winds continued to produce poor air quality during the last 24 hours. Vent glow was too weak to be recorded by the webcam overnight. This morning, weak winds are allowing the plume to rise a drift in various directions probably resulting in continuing poor air quality today.
Small amounts of tephra continued to be produced, the collections continue to consistent mostly of glassy spatter as has been the case since early September. The vent continues to be noisy with the distant surf sounds predominating.
Sulfur dioxide emission rates remain elevated and variable. The most recent average measurement was 500 tonnes/day on October 24, compared to the 2003-2007 average rate of 140 tonnes/day. Moderate trade winds are needed for good emission rate measurements.
The network of tiltmeters within Kilauea caldera recorded the inflation portion of the ongoing DI tilt event starting at about 2 am. The GPS receiver networks (less sensitive than tiltmeters) recorded small changes but no significant extension or contraction over the past two weeks.
Seismic activity continued to be focused on the south caldera; tremor levels dropped with the start of inflation. A total of 11 earthquakes were located beneath Kilauea or nearby, including 7 beneath the south caldera and 2 on south flank faults, with the number of RB2S2BL earthquakes increasing to around 60/day.
Last 24 hours at the middle east rift zone vents and flow field: Magma continues to degas through Pu`u `O`o Crater. The most recent sulfur dioxide measurement of 1,100 tonnes/day on October 24 is below the 2005-2007 average of about 2,000 tonnes/day for this vent; Pu`u `O`o emission rates have been slowly declining since early August. No incandescence was observed within the crater overnight.
Pu`u `O`o continues to deflate/collapse. The tiltmeter on the north side of Pu`u `O`o finally recorded the inflation portion of the ongoing DI tilt event at about 11:15 am simultaneous with rain which may have also influenced tilt. GPS stations spanning the crater (less sensitive than tiltmeters) recorded weak contraction across the crater. Seismic tremor levels near Pu`u `O`o and the TEB vent remain at low values; at least 4 minutes-long bursts of tremor occurred near the TEB vent starting around 6:30 pm yesterday resulting in currently higher tremor values.
Lava from the TEB vent and the rootless shield complex again flows through tubes to the ocean. Weak incandescence was seen from the TEB vent overnight. GOES-WEST views were blocked by high altitude clouds over the state. This morning, CD officials reported that the ocean entry resumed about 7 am.
Definitions of terms used in the update:
FLIR: Forward Looking InfraRed, a camera which directly images heat rather than visible light. If volcanic fume is not too rich in water vapor, a FLIR can see through it to image hot surfaces.
pali: Hawaiian word for cliff or steep incline. In the context of the TEB flow field, 'pali' usually refers to Pulama pali that bisects the abandoned Royal Gardens subdivision.
CD: Hawai`i County Civil Defense
DOH air quality monitoring: see Hawai`i State Department of Health Air Quality website http://hawaii.gov/doh/air-quality/index.html .
bomb: lava fragment ejected into the air while molten acquiring aerodynamic shapes in flight; the term is restricted to pieces larger than 6.4 cm (2.5 in.). See http://volcanoes.usgs.gov/Products/Pglossary/bomb.html
hybrid, or explosion, seismic signals: complex earthquakes that are a hybrid of different signals. They start as a high frequency earthquake, similar to typical rock-breaking or rock fall events, that transitions to very long, 20-30 second, period (VLP) oscillations that continue for several minutes. At HVO, we observed these signals with the four small Halema`uma`u explosive eruptions in March, April, and August 2008. Several more similar signals, some as strong as the explosion signals associated with the four explosive eruptions, have been recorded without obvious evidenceof surface eruption such as rock fragments or other debris.
MODIS satellite: a NASA satellite pair, Aqua and Terra, which passes over Hawai`i twice a day. During daylight hours, the images are taken at about 11 am and 2 pm H.s.t. This imagery can be viewed about 3-5 hours after acquisition at http://rapidfire.sci.gsfc.nasa.gov/subsets/?subset=AERONET_Mauna_Loa.
GOES-WEST satellite: a geostationary NOAA satellite used most often for weather tracking. Images are typically acquired every 15 minutes. The loop http://www.ssd.noaa.gov/VAAC/kilauea/sloop-vis.html is posted by the Washington DC Volcanic Ash Advisory Center for the purpose of tracking emissions from Hawai`i volcanoes. The imagery automatically switches from infrared at night to visual during the day. Recently, it has been useful for tracking volcanic gas emissions from Halema`uma`u, Pu`u `O`o, and the Waikupanaha ocean entry during the day and hot lava flows at night.
Volcano Watch: weekly newspaper-like article written by HVO scientists on a volcano topic of interest. These articles are usually printed in the Sunday editions of the Hawai`i Island newspapers Hawaii Tribune Herald and West Hawaii Today. More than 800 of these articles have been written and are archived on the HVO website (menu at the bottom of the homepage hvo.wr.usgs.gov).
VLP seismic tremor: seismic tremor is continuous ground vibrations simultaneously at many different frequencies. VLP is a very long period or very low frequency component which, at the Halema`uma`u vent, has a period of 20-30 seconds or a frequency of 0.03-0.05 cycles per second (Hertz or Hz).
RB2S2BL earthquakes: earthquakes that were recorded but too small to be located. These quakes have magnitudes less than 1.7 and may only be recorded on one or two seismometers. Recording at a minimum of 4 seismometer sites is required to locate an earthquake.
wink: an abrupt shutting off of incandescence at a vent lasting for several minutes. At the Halema`uma`u vent, winks usually start with or immediately follow a small, local earthquake. The diminishment of incandescence is due to the plume changing from translucent to opaque with rock dust.
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
microradian: a measure of angle equivalent to 0.000057 degrees.
ppm: parts-per-million; 10,000 ppm = 1 %.
littoral cone: usually small cones built near active ocean entries; the cones are constructed of tephra from steam explosions that are sometimes produced when 1,150 degree C lava enters the 25 degree C ocean.
incandescence: the production of visible light from a hot surface. The color of the light is related to the temperature of the surface. Some surfaces can display dull red incandescence at temperatures as low as 430 degrees Centigrade (806 degrees Fahrenheit). By contrast, molten lava displays bright orange to orange-yellow light from surfaces that are hotter than 900 degrees C (1,650 degrees F).
tephra: all material deposited by fallout from an eruption-related plume, regardless of size.
ash: tephra less than 2 mm (5/64 inches) in size.
TEB: Thanksgiving Eve Breakout, the designation used for lava flows that started with a breakout on November 21, 2007.
DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a volcanic event of uncertain significance. DI events are recorded by tiltmeters at Kilauea summit as an abrupt deflation of up to a few microradians in magnitude lasting several hours to 2-3 days followed by an abrupt inflation of approximately equal magnitude. The tilt events are usually accompanied by an increase in summit tremor during the deflation phase. A careful analysis of these events suggests that they may be related to changes in magma supply to a storage reservoir at less than 1 km depth, just east of Halema`uma`u crater. Usually, though not always, these changes propagate through the magma conduit from the summit to the eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by 1-2 hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
Maps, photos, webcam views, and other information about Kilauea Volcano are available at http://volcano.wr.usgs.gov/kilaueastatus.php. A daily update summary is available by phone at (808) 967-8862.
A map with details of earthquakes located within the past two weeks can be found at http://tux.wr.usgs.gov/
A definition of alert levels can be found at http://volcanoes.usgs.gov/2006/warnschemes.html