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Recent Kilauea Status Reports, Updates, and Information Releases
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 Kalapana Viewing Area status can be found at 961-8093. All times are Hawai`i Standard Time.
KILAUEA VOLCANO (CAVW #1302-01-)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WARNING
Current Aviation Color Code: RED
Activity Summary for past 24 hours: There have been significant changes as Kilauea volcano continued to erupt at two locations: On the east rift zone, a fissure eruption that started Saturday afternoon continued intermittently at locations approximately 2-3.5 km WSW of Pu`u `O`o. Pu`u `O`o Crater and the TEB/Nov. 29 flows were inactive this morning. At the summit, the lava lake level remained deep below the rim of the vent inset within the east wall of Halema`uma`u Crater. Summit and east rift zone seismicity remained significantly elevated.
Past 24 hours at Kilauea summit: The lava level remained very deep within the vent inset within the east wall of Halema`uma`u Crater. The summit tiltmeter network recorded slowing deflation. Seismic tremor levels remained significantly elevated.
Eighteen earthquakes were strong enough to be located within Kilauea volcano - 10 were clustered in the east rift zone near the fissure eruption, five were beneath the summit area, and three were on south flank faults.
The summit gas plume is moving to the southwest this morning. The most recent (preliminary) sulfur dioxide emission rate measurement was 600 tonnes/day on March 6, 2011.
Past 24 hours at the middle east rift zone vents: The fissure eruption that started Saturday afternoon continued through this morning with vigorous spattering from the west end of the fissure which is just east of Napau Crater and about 2-3.5 km WSW of Pu`u `O`o. The most recent (preliminary) sulfur dioxide emission rate measurement was 7,000 tonnes/day on March 6, 2011 from all east rift zone sources.
The tiltmeter on the north flank of Pu`u `O`o recorded slowing deflation. Seismic tremor levels remain significantly elevated and variable in this part of the rift zone.
There was visible incandescence deep within a hornito over Fissure D (the TEB vent) but no other visible activity within the collapsed Pu`u `O`o Crater nor on the TEB/Nov. 29 flow field.
Hawai`i Volcanoes National Park message: In response to the current volcanic conditions, Hawai'i Volcanoes National Park has closed the Chain of Craters Road and all east rift zone and coastal trails, along with the Kulanaokuaiki campground, until further notice.
Hazard Summary: East rift vents and flow field - near-vent areas could erupt or collapse without warning; potentially-lethal concentrations of sulfur dioxide gas are present within 1 km downwind of vent areas. Kilauea Crater - explosive events are capable of ejecting rocks and lava several hundred meters (yards) from the Halema`uma`u vent; ash and potentially-lethal concentrations of sulfur dioxide are present within 1 km downwind.
Maps, photos, Webcam views, and other information about Kilauea Volcano are available at http://volcanoes.usgs.gov/hvo/activity/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/activity/alertsystem/index.php
Definitions of Terms Used:
methane blast: when lava flows advance through a vegetated area, small explosions sometimes occur due to the ignition of methane gas, produced by lava-cooked plants and trapped beneath the ground surface. Injuries can occur as the result of airborne rock fragments.
rootless shields: a small mound of lava, located directly over an active lava tube that is built by repeated overflows from its top. These are rootless because they are fed from a lava tube and not from a deeper source (vent). The upper part of the TEB lava tube has numerous rootless shields built from the vent down to about the 1,500 ft elevation.
mauka, makai: Hawaiian terms for directions relative to the coast - makai (toward the coast) and mauka (away from the coast).
composite seismic events: is a seismic signal with multiple distinct phases that has been recorded frequently at HVO from the Halema`uma`u Overlook vent area since its explosive opening in March, 2008. For the composite events recorded at Halema`uma`u, we typically see an initial high frequency vibration lasting for a few seconds that have been correlated with rockfalls. This is followed by about 30 seconds of a long-period (LP) oscillation with an approximately 2- to 3-second period. The final phase of the signal is several minutes of a very-long-period (VLP) oscillation with an approximately 25- to 30-second period. The LP signals are interpreted to be from the uppermost portion of the conduit and VLP signals are interpreted to be fluid passing through a deep constriction in the conduit through which lava rises to the pond surface we see in the webcam.
high lava stands: Starting in June, 2010, lava within the Halema`uma`u Overlook vent rises 20-40 m over an interval of 10s of minutes, remains high for up to several hours, and then drains back to its previous level, while vigorously degassing, in several minutes. During the high stand, the gas plume becomes wispy, gas emissions halve in rate, and seismic tremor drops to very low levels; the high stand is followed by a strong seismic tremor burst, lasting several minutes, accompanying the draining. Many, but not all, high lava stands start with a rockfall event, some accompanied by VLP seismic energy.
Inflating surface flow: is a lava flow that may not advance but continues to thicken as its top and bottom crusts grow around a continuously replenished molten interior. This can be visualized as a large flat bladder of molten lava that could burst along its edges at any time.
Hakuma horst: a horst is an section of earth that is raised between two nearly parallel faults so that its surface is higher than the surrounding ground. The Hakuma horst is located along the coast west of Kalapana; it was responsible for diverting lava through Kalapana village in 1990 and appears to be having a similar influence on lava flows in 2010.
Halema`uma`u Overlook vent: has been difficult to describe concisely. The vent is actually a pit, or crater, in the floor of the larger Halema`uma`u Crater in the floor of the larger Kilauea caldera or crater - a crater within a crater within a crater. It is easiest to describe as a pit inset within the floor of a crater within a caldera. The pit is about 140 m (460 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at the pit floor, and is about 200 m (660 ft) deep. As of November, 2009, a lava pond surface has been visible in a hole in the floor of this pit.
glow: light from an unseen source; indirect light.
incandescence: the production of visible light from a hot surface. The term also refers to the light emitted from a hot surface. The color of the light is related to surface temperature. 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).
CD: Hawai`i County Civil Defense
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
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.
microradian: a measure of angle equivalent to 0.000057 degrees.
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 east rift eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by several hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.
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.
KILAUEA VOLCANO (CAVW #1302-01-)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WARNING
Current Aviation Color Code: RED
A fissure that opened on Kilauea's east rift zone after yesterday's collapse of the Pu'u 'O'o crater floor continues to erupt lava. Activity along the fissure was sporadic overnight and throughout today, with periods of quiet punctuated by episodes of lava spattering up to 25 m (80 ft) high.
The fissure is located west-southwest of Pu'u 'O'o in a remote area of Hawai'i Volcanoes National Park. Due to the ongoing volcanic activity, Park closures remain in effect in this area.
Live views of Kilauea's fissure eruption are now possible via a Webcam installed by the USGS Hawaiian Volcano Observatory (HVO) this afternoon. The Webcam images, which are updated every five minutes, can be accessed at http://volcanoes.usgs.gov/hvo/cams/NCcam/.
Measurements made by HVO scientists today show that the Pu'u 'O'o crater floor dropped at least 115 m (377 ft) during Saturday's collapse. The only signs of activity within the crater today were infrequent cascades of rock fragments falling from collapse blocks. This activity is visible when Pu'u 'O'o Webcam views, accessible at http://volcanoes.usgs.gov/hvo/cams/POcam/, are not obscured by volcanic fume.
Lava flows on the pali and coastal plain are still active, but sluggish. Whether these flows are residual lava draining through the tube system or outbreaks that continue to be fed by lava from the east rift zone vent is not yet known. Based on similar events in past years, it will take a day or two to see if the lava supply has been cut off by the uprift fissure eruption.
At Kilauea's summit, the lava lake has receded deep within the vent in Halema'uma'u Crater and is now barely visible in HVO's Webcam images (http://volcanoes.usgs.gov/hvo/cams/HMcam/). Small collapses of the vent walls occasionally produce dusty-brown plumes that can be seen from Park visitor overlooks.
Earthquakes are occurring at lower rates in the Napau Crater area adjacent to the new fissure eruption and beneath the summit caldera, but seismic tremor is significantly elevated in both areas. Summit deflation continues, but began to slow this afternoon. Deflation of the Pu'u 'O'o area has slowed throughout the day.
Daily updates about Kilauea's ongoing eruptions, recent images and videos of summit and east rift zone volcanic activity, and data about recent earthquakes are posted on the HVO Web site at http://hvo.wr.usgs.gov. Additional status reports will be posted as warranted.
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.
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 Kalapana Viewing Area status can be found at 961-8093. All times are Hawai`i Standard Time.
KILAUEA VOLCANO (CAVW #1302-01-)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WARNING
Current Aviation Color Code: RED
Activity Summary for past 24 hours: There have been significant changes as Kilauea volcano continued to erupt at two locations: On the east rift zone, a fissure eruption that started yesterday afternoon is continuing intermittently at a location approximately 2 km WSW of Pu`u `O`o. The floor of Pu`u `O`o collapsed yesterday and the Nov. 29 flows were weakly active this morning. At the summit, the lava lake level receded deep below the rim of the vent inset within the east wall of Halema`uma`u Crater. Summit and east rift zone seismicity remained significantly elevated.
Past 24 hours at Kilauea summit: The lava level receded rapidly through yesterday afternoon and evening but seemed to slow since midnight; at 7:03 am, a large collapse caused the lava lake level to recede almost beyond view of the webcam. The summit tiltmeter network recorded continued deflation at a steady rate amounting to almost 28 microradians by this morning. Seismic tremor levels elevated further between about 2 and 4:30 pm yesterday and then increased to almost ten times background between 8 pm last night and 4 am this morning.
Approximately one-hundred-and-fifty earthquakes were strong enough to be located within Kilauea volcano - more than 100 were clustered in the east rift zone, in location, between Maka`opuhi and Napau Crater and, in time, between 2 pm and midnight and about 30 were located within the summit area including five estimated to be magnitude-2.5 and above this morning.
The summit gas plume is wispy and moving to the southwest this morning. The most recent (preliminary) sulfur dioxide emission rate measurement was 400 tonnes/day on March 2, 2011 averaged over at least one high lava stand during which the emissions may be halved.
Past 24 hours at the middle east rift zone vents: The small fissure eruption that started around 5 pm yesterday had paused by the time ground crews arrived at 9:55 pm; however, the eruption resumed from approximately the same location by 00:40 am this morning before stopping a second time at 1:50 am. At 4:22 am this morning, spattering to the height of nearby trees resumed. Two more fissures opened in the same vicinity at 5:45 am this morning producing more gas than lava. Gas jetting has been audible for most of these spattering episodes as activity waxes and wanes.
The tiltmeter on the north flank of Pu`u `O`o recorded over 150 microradians of deflation from 2 pm yesterday; the deflation rate has markedly slowed by this morning. Seismic tremor levels remain significantly elevated and variable in this part of the rift zone.
Incandescence within the collapsed Pu`u `O`o was due to rockfalls. Activity on the Nov. 29 flow was significantly weaker overnight and may be residual lava left in the tube. Thanks to the Hawai`i County Fire Department for providing a helicopter for yesterday afternoon's overflight to assess eruption conditions. HVO crews will do another overflight this morning.
Hawai`i Volcanoes National Park message: In response to the current volcanic conditions, Hawai'i Volcanoes National Park has closed the Chain of Craters Road and all east rift zone and coastal trails, along with the Kulanaokuaiki campground, until further notice.
Hazard Summary: East rift vents and flow field - near-vent areas could erupt or collapse without warning; potentially-lethal concentrations of sulfur dioxide gas are present within 1 km downwind of vent areas. Kilauea Crater - explosive events are capable of ejecting rocks and lava several hundred meters (yards) from the Halema`uma`u vent; ash and potentially-lethal concentrations of sulfur dioxide are present within 1 km downwind.
Maps, photos, Webcam views, and other information about Kilauea Volcano are available at http://volcanoes.usgs.gov/hvo/activity/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/activity/alertsystem/index.php
Definitions of Terms Used:
methane blast: when lava flows advance through a vegetated area, small explosions sometimes occur due to the ignition of methane gas, produced by lava-cooked plants and trapped beneath the ground surface. Injuries can occur as the result of airborne rock fragments.
rootless shields: a small mound of lava, located directly over an active lava tube that is built by repeated overflows from its top. These are rootless because they are fed from a lava tube and not from a deeper source (vent). The upper part of the TEB lava tube has numerous rootless shields built from the vent down to about the 1,500 ft elevation.
mauka, makai: Hawaiian terms for directions relative to the coast - makai (toward the coast) and mauka (away from the coast).
composite seismic events: is a seismic signal with multiple distinct phases that has been recorded frequently at HVO from the Halema`uma`u Overlook vent area since its explosive opening in March, 2008. For the composite events recorded at Halema`uma`u, we typically see an initial high frequency vibration lasting for a few seconds that have been correlated with rockfalls. This is followed by about 30 seconds of a long-period (LP) oscillation with an approximately 2- to 3-second period. The final phase of the signal is several minutes of a very-long-period (VLP) oscillation with an approximately 25- to 30-second period. The LP signals are interpreted to be from the uppermost portion of the conduit and VLP signals are interpreted to be fluid passing through a deep constriction in the conduit through which lava rises to the pond surface we see in the webcam.
high lava stands: Starting in June, 2010, lava within the Halema`uma`u Overlook vent rises 20-40 m over an interval of 10s of minutes, remains high for up to several hours, and then drains back to its previous level, while vigorously degassing, in several minutes. During the high stand, the gas plume becomes wispy, gas emissions halve in rate, and seismic tremor drops to very low levels; the high stand is followed by a strong seismic tremor burst, lasting several minutes, accompanying the draining. Many, but not all, high lava stands start with a rockfall event, some accompanied by VLP seismic energy.
Inflating surface flow: is a lava flow that may not advance but continues to thicken as its top and bottom crusts grow around a continuously replenished molten interior. This can be visualized as a large flat bladder of molten lava that could burst along its edges at any time.
Hakuma horst: a horst is an section of earth that is raised between two nearly parallel faults so that its surface is higher than the surrounding ground. The Hakuma horst is located along the coast west of Kalapana; it was responsible for diverting lava through Kalapana village in 1990 and appears to be having a similar influence on lava flows in 2010.
Halema`uma`u Overlook vent: has been difficult to describe concisely. The vent is actually a pit, or crater, in the floor of the larger Halema`uma`u Crater in the floor of the larger Kilauea caldera or crater - a crater within a crater within a crater. It is easiest to describe as a pit inset within the floor of a crater within a caldera. The pit is about 140 m (460 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at the pit floor, and is about 200 m (660 ft) deep. As of November, 2009, a lava pond surface has been visible in a hole in the floor of this pit.
glow: light from an unseen source; indirect light.
incandescence: the production of visible light from a hot surface. The term also refers to the light emitted from a hot surface. The color of the light is related to surface temperature. 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).
CD: Hawai`i County Civil Defense
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
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.
microradian: a measure of angle equivalent to 0.000057 degrees.
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 east rift eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by several hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.
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.
HVO/USGS Volcanic Activity Notice
Volcano: Kilauea (CAVW #1302-01-)
Current Volcano Alert Level: WARNING
Previous Volcano Alert Level: WATCH
Current Aviation Color Code: RED
Previous Aviation Color Code: ORANGE
Issued: Saturday, March 5, 2011, 5:39 PM HST (20110306/0339Z)
Source: Hawaiian Volcano Observatory
Notice Number: 2011/H1
Location: N 19 deg 25 min W 155 deg 17 min
Elevation: 4091 ft (1247 m)
Area: HI Hawaii and Pacific Ocean
Volcanic Activity Summary: At 1:42 p.m. this afternoon, HVO instruments indicated the onset of rapid deflation at Pu'u 'Ō'ō and increased tremor along Kīlauea's middle east rift zone. At 2:00 p.m., Kīlauea's summit began to deflate.
Between 2:16 and 2:21 p.m., the floor of the Pu'u 'Ō'ō crater began to collapse, and within 10 minutes, incandescent ring fractures opened on the crater floor a few tens of meters away from the crater wall. As the floor continued to drop, lava appeared in the center of the crater floor, the NE spatter cone collapsed, and an obvious scarp developed on the west side of the crater floor, with lava cascading over the scarp toward the center of the crater.
At 2:41 p.m., the scarp on the west side of the crater floor appeared to disintegrate, exposing incandescent rubble, and the lava in the center of the crater enlarged.
At 2:46 p.m., the collapse of a large block along the east crater wall produced a dust plume and the lava continued to enlarge.
Webcam images showed that the Pu'u 'Ō'ō crater floor continued to drop through 4:26 p.m., when fume obscured the camera view.
Coincident with the collapse, an earthquake swarm began along Kīlauea's middle east rift zone in the area of Maka`opuhi and Nāpau craters. Tiltmeters in this area show continued deflation.
At 5:15 p.m., an HVO geologist flying over Kīlauea's middle east zone reported "an eruption in Napau Crater." When more is known about this eruption, an updated status report will be posted.
Kīlauea's summit continues to deflate. The lava lake level within the Halema'uma'u Crater vent continues to drop, facilitating rockfalls from the vent wall.
Daily updates on Kilauea's ongoing eruptions (summit and east rift zone) will be posted each morning. These will be supplemented by additional status reports and updates as warranted.
Maps, photos, Webcam views, and other information about Kilauea Volcano are available at http://volcanoes.usgs.gov/hvo/activity/kilaueastatus.php.
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.
Recent Observations:
[Volcanic cloud height] Unknown
[Other volcanic cloud information] Unknown
Contacts: HVO media contact
askHVO@usgs.gov
Next Notice: A new VAN will be issued if conditions change significantly or alert levels are modified. While a VAN is in effect, regularly scheduled updates are posted at http://hvo.wr.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.
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 Kalapana Viewing Area status can be found at 961-8093. All times are Hawai`i Standard Time.
KILAUEA VOLCANO (CAVW #1302-01-)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE
Activity Summary for past 24 hours: Kilauea volcano continued to erupt at two locations: On the east rift zone, lava from a source within Pu`u `O`o Crater flowed across the western floor and scattered lava breakouts continued from the Nov. 29 flow near Kalapana. At the summit, the lava lake level was well below the vent rim inset within the east wall of Halema`uma`u Crater; seismicity within the upper east rift zone was elevated. Sulfur dioxide emission rates from the summit and east rift zone vents also remained elevated.
Past 24 hours at Kilauea summit: The lava level rose multiple times to about 70 m (230 ft) below the Halema`uma`u Crater floor. The summit tiltmeter network recorded no significant long-term ground tilting; the largest tilt signal was minor deflations accompanying each high lava stand (rise/fall or filling/draining cycles) after they resumed around 4 pm yesterday. Seismic tremor levels were elevated - each rise in lava level was accompanied by a corresponding drop in tremor amplitude followed by a strong tremor burst as lava briefly drained to a lower level.
Twenty-five earthquakes were strong enough to be located within Kilauea volcano - fifteen within the upper east rift zone (UERZ; most were located between Keanakako`i and Hi`iaka Craters), nine on south flank faults, and one beneath the area of the summit; most recently, UERZ seismicity has been elevated during the last two DI infationary episodes and nearly non-existent during the two preceding DI deflationary periods - we continue to watch the elevated seismicity closely for other patterns. The network of GPS receivers recorded extension across the summit mimicking the current tilt.
The summit gas plume is wispy and moving to the west this morning. The most recent (preliminary) sulfur dioxide emission rate measurement was 400 tonnes/day on March 2, 2011 averaged over at least one high lava stand during which the emissions may be halved. In addition to gas, the plume wafted small amounts of ash-sized tephra, mostly bits of fresh spatter, that were deposited on nearby downwind surfaces.
Past 24 hours at the middle east rift zone vents: Lava flows continued from the northwest cone continued to cover the western crater floor of Pu'u `O`o through dawn. The east wall and northeast cone sources glowed overnight.
The tiltmeter on the north flank of Pu`u `O`o recorded minor rain-induced inflation around 7:30 pm at which time superimposed oscillations suggestive of pulsed lava effusion grew stronger. The network of GPS receivers recorded extension and contraction across the cone mimicking the ground tilt (doesn't include rain-induced tilt). Seismic tremor levels near Pu`u `O`o remained low and steady. The most recent (preliminary) sulfur dioxide emission rate measurement from east rift zone vents was 300 tonnes/day on February 8, 2011; new measurements must await the return of moderate trade winds.
The two branches of the November 29 flow (1,200 ft elevation tube breach) continued to host scattered breakouts on the pali and the coastal plain. The lowest breakouts from the eastern branch continued to be active along the eastern margin of earlier flows below the 130 ft elevation (estimated) and were still an estimated 0.9 km (0.5 mi) west of the Kalapana Gardens road/highway 130 intersection.
Hazard Summary: Kalapana - active lava flows continue to threaten structures in Kalapana Gardens subdivision and adjacent areas over the coming days, weeks, or even months; the hazard is greatest for structures that are located within 300 m (985 ft) of actively inflating or advancing flows and that are topographically less than 2 m (6 ft) higher than the tops of approaching flows; any structure within these horizontal and vertical parameters could potentially be destroyed by advancing lava within 24 hours. East rift vents and flow field - near-vent areas could erupt or collapse without warning; potentially-lethal concentrations of sulfur dioxide gas are present within 1 km downwind of vent areas. Ocean Entries: lava deltas can collapse without warning, produce hot rock falls that can reach 400 m (0.25 mi) inland, as well as seaward, and produce large local scalding waves; the gas/steam plume produced by lava entering the ocean contains fine lava fragments and acid gases and droplets that can be harmful to human health at moderate distances and potentially-lethal on the delta. These rapidly changing conditions near the ocean entry have been responsible for many injuries and a few deaths. Kilauea Crater - explosive events are capable of ejecting rocks and lava several hundred meters (yards) from the Halema`uma`u vent; ash and potentially-lethal concentrations of sulfur dioxide are present within 1 km downwind.
Kalapana Public Access Information from Hawai`i County Civil Defense: Kalapana Gardens is a private subdivision and access will only be granted to subdivision residents. Private property borders highway 130 through Kalapana, and visitors to the Hawai`i County Lava Viewing Area are not allowed access off the highway easement. Hawai`i County Police will be monitoring the area. Hawai`i County Lava Viewing Area status can be found by calling 961-8093.
Maps, photos, Webcam views, and other information about Kilauea Volcano are available at http://volcanoes.usgs.gov/hvo/activity/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/activity/alertsystem/index.php
Definitions of Terms Used:
methane blast: when lava flows advance through a vegetated area, small explosions sometimes occur due to the ignition of methane gas, produced by lava-cooked plants and trapped beneath the ground surface. Injuries can occur as the result of airborne rock fragments.
rootless shields: a small mound of lava, located directly over an active lava tube that is built by repeated overflows from its top. These are rootless because they are fed from a lava tube and not from a deeper source (vent). The upper part of the TEB lava tube has numerous rootless shields built from the vent down to about the 1,500 ft elevation.
mauka, makai: Hawaiian terms for directions relative to the coast - makai (toward the coast) and mauka (away from the coast).
composite seismic events: is a seismic signal with multiple distinct phases that has been recorded frequently at HVO from the Halema`uma`u Overlook vent area since its explosive opening in March, 2008. For the composite events recorded at Halema`uma`u, we typically see an initial high frequency vibration lasting for a few seconds that have been correlated with rockfalls. This is followed by about 30 seconds of a long-period (LP) oscillation with an approximately 2- to 3-second period. The final phase of the signal is several minutes of a very-long-period (VLP) oscillation with an approximately 25- to 30-second period. The LP signals are interpreted to be from the uppermost portion of the conduit and VLP signals are interpreted to be fluid passing through a deep constriction in the conduit through which lava rises to the pond surface we see in the webcam.
high lava stands: Starting in June, 2010, lava within the Halema`uma`u Overlook vent rises 20-40 m over an interval of 10s of minutes, remains high for up to several hours, and then drains back to its previous level, while vigorously degassing, in several minutes. During the high stand, the gas plume becomes wispy, gas emissions halve in rate, and seismic tremor drops to very low levels; the high stand is followed by a strong seismic tremor burst, lasting several minutes, accompanying the draining. Many, but not all, high lava stands start with a rockfall event, some accompanied by VLP seismic energy.
Inflating surface flow: is a lava flow that may not advance but continues to thicken as its top and bottom crusts grow around a continuously replenished molten interior. This can be visualized as a large flat bladder of molten lava that could burst along its edges at any time.
Hakuma horst: a horst is an section of earth that is raised between two nearly parallel faults so that its surface is higher than the surrounding ground. The Hakuma horst is located along the coast west of Kalapana; it was responsible for diverting lava through Kalapana village in 1990 and appears to be having a similar influence on lava flows in 2010.
Halema`uma`u Overlook vent: has been difficult to describe concisely. The vent is actually a pit, or crater, in the floor of the larger Halema`uma`u Crater in the floor of the larger Kilauea caldera or crater - a crater within a crater within a crater. It is easiest to describe as a pit inset within the floor of a crater within a caldera. The pit is about 140 m (460 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at the pit floor, and is about 200 m (660 ft) deep. As of November, 2009, a lava pond surface has been visible in a hole in the floor of this pit.
glow: light from an unseen source; indirect light.
incandescence: the production of visible light from a hot surface. The term also refers to the light emitted from a hot surface. The color of the light is related to surface temperature. 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).
CD: Hawai`i County Civil Defense
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
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.
microradian: a measure of angle equivalent to 0.000057 degrees.
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 east rift eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by several hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.
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.
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 Kalapana Viewing Area status can be found at 961-8093. All times are Hawai`i Standard Time.
KILAUEA VOLCANO (CAVW #1302-01-)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE
Activity Summary for past 24 hours: DI inflation is slowing while Kilauea volcano continued to erupt at two locations: On the east rift zone, lava flows from sources within Pu`u `O`o Crater covered the western floor and scattered lava breakouts continued from the Nov. 29 flow near Kalapana. At the summit, vent rim collapses just after noon caused small explosive events that deposited ash to the north and caused temporary drops in lava level; seismicity within the upper east rift zone was elevated. Sulfur dioxide emission rates from the summit and east rift zone vents also remained elevated.
Past 24 hours at Kilauea summit: The lava level rose multiple times to about 70 m (230 ft) below the Halema`uma`u Crater floor; several rim collapses yesterday, with the largest just after noon, produced ash fall on the north caldera rim near the Kilauea Visitor's Center and in nearby Volcano Village; the collapses caused prolonged periods of low lava levels that recovered after several hours. The summit tiltmeter network recorded continued slowing of DI inflation with minor deflations accompanying each back-to-back high lava stand (rise/fall or filling/draining cycles). Seismic tremor levels were elevated - each rise in lava level was accompanied by a corresponding drop in tremor amplitude followed by a strong tremor burst as lava briefly drained to a lower level. Each rockfall is the start of a strong tremor burst that decays in amplitude for several hours.
For the third day, an unusually large number of forty-eight earthquakes were strong enough to be located within Kilauea volcano - thirty-seven within the upper east rift zone (UERZ; most were located between Keanakako`i and Hi`iaka Craters), six on south flank faults, and five beneath the area south, west, and north of the summit; most recently, UERZ seismicity has been elevated during the last two DI infationary episodes and nearly non-existent during the preceding DI deflationary periods - we continue to watch the elevated seismicity closely for other patterns. The network of GPS receivers recorded extension across the summit mimicking the current tilt.
The summit gas plume is obscured by fog this morning. The most recent (preliminary) sulfur dioxide emission rate measurement was 400 tonnes/day on March 2, 2011 averaged over at least one high lava stand during which the emissions may be halved. In addition to gas, the plume wafted small amounts of ash-sized tephra, mostly bits of fresh spatter, that were deposited on nearby downwind surfaces.
Past 24 hours at the middle east rift zone vents: Lava flows continued from the northwest cone continued to cover the western crater floor of Pu'u `O`o through dawn. The east wall and northeast cone sources glowed overnight.
The tiltmeter on the north flank of Pu`u `O`o recorded tilt variations with superimposed oscillations suggestive of pulsed lava effusion. The network of GPS receivers recorded extension and contraction across the cone mimicking the tilt. Seismic tremor levels near Pu`u `O`o remained low and steady. The most recent (preliminary) sulfur dioxide emission rate measurement from east rift zone vents was 300 tonnes/day on February 8, 2011; new measurements must await the return of moderate trade winds.
The two branches of the November 29 flow (1,200 ft elevation tube breach) continued to host scattered breakouts on the pali and the coastal plain. The lowest breakouts from the eastern branch continued to be active along the eastern margin of earlier flows below the 130 ft elevation (estimated) and were still an estimated 0.9 km (0.5 mi) west of the Kalapana Gardens road/highway 130 intersection when checked during an HVO overflight yesterday.
Hazard Summary: Kalapana - active lava flows continue to threaten structures in Kalapana Gardens subdivision and adjacent areas over the coming days, weeks, or even months; the hazard is greatest for structures that are located within 300 m (985 ft) of actively inflating or advancing flows and that are topographically less than 2 m (6 ft) higher than the tops of approaching flows; any structure within these horizontal and vertical parameters could potentially be destroyed by advancing lava within 24 hours. East rift vents and flow field - near-vent areas could erupt or collapse without warning; potentially-lethal concentrations of sulfur dioxide gas are present within 1 km downwind of vent areas. Ocean Entries: lava deltas can collapse without warning, produce hot rock falls that can reach 400 m (0.25 mi) inland, as well as seaward, and produce large local scalding waves; the gas/steam plume produced by lava entering the ocean contains fine lava fragments and acid gases and droplets that can be harmful to human health at moderate distances and potentially-lethal on the delta. These rapidly changing conditions near the ocean entry have been responsible for many injuries and a few deaths. Kilauea Crater - explosive events are capable of ejecting rocks and lava several hundred meters (yards) from the Halema`uma`u vent; ash and potentially-lethal concentrations of sulfur dioxide are present within 1 km downwind.
Kalapana Public Access Information from Hawai`i County Civil Defense: Kalapana Gardens is a private subdivision and access will only be granted to subdivision residents. Private property borders highway 130 through Kalapana, and visitors to the Hawai`i County Lava Viewing Area are not allowed access off the highway easement. Hawai`i County Police will be monitoring the area. Hawai`i County Lava Viewing Area status can be found by calling 961-8093.
Maps, photos, Webcam views, and other information about Kilauea Volcano are available at http://volcanoes.usgs.gov/hvo/activity/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/activity/alertsystem/index.php
Definitions of Terms Used:
methane blast: when lava flows advance through a vegetated area, small explosions sometimes occur due to the ignition of methane gas, produced by lava-cooked plants and trapped beneath the ground surface. Injuries can occur as the result of airborne rock fragments.
rootless shields: a small mound of lava, located directly over an active lava tube that is built by repeated overflows from its top. These are rootless because they are fed from a lava tube and not from a deeper source (vent). The upper part of the TEB lava tube has numerous rootless shields built from the vent down to about the 1,500 ft elevation.
mauka, makai: Hawaiian terms for directions relative to the coast - makai (toward the coast) and mauka (away from the coast).
composite seismic events: is a seismic signal with multiple distinct phases that has been recorded frequently at HVO from the Halema`uma`u Overlook vent area since its explosive opening in March, 2008. For the composite events recorded at Halema`uma`u, we typically see an initial high frequency vibration lasting for a few seconds that have been correlated with rockfalls. This is followed by about 30 seconds of a long-period (LP) oscillation with an approximately 2- to 3-second period. The final phase of the signal is several minutes of a very-long-period (VLP) oscillation with an approximately 25- to 30-second period. The LP signals are interpreted to be from the uppermost portion of the conduit and VLP signals are interpreted to be fluid passing through a deep constriction in the conduit through which lava rises to the pond surface we see in the webcam.
high lava stands: Starting in June, 2010, lava within the Halema`uma`u Overlook vent rises 20-40 m over an interval of 10s of minutes, remains high for up to several hours, and then drains back to its previous level, while vigorously degassing, in several minutes. During the high stand, the gas plume becomes wispy, gas emissions halve in rate, and seismic tremor drops to very low levels; the high stand is followed by a strong seismic tremor burst, lasting several minutes, accompanying the draining. Many, but not all, high lava stands start with a rockfall event, some accompanied by VLP seismic energy.
Inflating surface flow: is a lava flow that may not advance but continues to thicken as its top and bottom crusts grow around a continuously replenished molten interior. This can be visualized as a large flat bladder of molten lava that could burst along its edges at any time.
Hakuma horst: a horst is an section of earth that is raised between two nearly parallel faults so that its surface is higher than the surrounding ground. The Hakuma horst is located along the coast west of Kalapana; it was responsible for diverting lava through Kalapana village in 1990 and appears to be having a similar influence on lava flows in 2010.
Halema`uma`u Overlook vent: has been difficult to describe concisely. The vent is actually a pit, or crater, in the floor of the larger Halema`uma`u Crater in the floor of the larger Kilauea caldera or crater - a crater within a crater within a crater. It is easiest to describe as a pit inset within the floor of a crater within a caldera. The pit is about 140 m (460 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at the pit floor, and is about 200 m (660 ft) deep. As of November, 2009, a lava pond surface has been visible in a hole in the floor of this pit.
glow: light from an unseen source; indirect light.
incandescence: the production of visible light from a hot surface. The term also refers to the light emitted from a hot surface. The color of the light is related to surface temperature. 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).
CD: Hawai`i County Civil Defense
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
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.
microradian: a measure of angle equivalent to 0.000057 degrees.
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 east rift eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by several hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.
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.
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 Kalapana Viewing Area status can be found at 961-8093. All times are Hawai`i Standard Time.
KILAUEA VOLCANO (CAVW #1302-01-)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE
Activity Summary for past 24 hours: DI inflation is ongoing while Kilauea volcano continued to erupt at two locations: On the east rift zone, lava flows from sources within Pu`u `O`o Crater covered the western floor and scattered lava breakouts continued from the Nov. 29 flow near Kalapana. At the summit, the lava lake level was steady within an eruptive vent inset within the east wall of Halema`uma`u Crater; seismicity within the upper east rift zone was elevated. Sulfur dioxide emission rates from the summit and east rift zone vents remained elevated.
Past 24 hours at Kilauea summit: The lava level seems to have remained at about 70 m (230 ft) below the Halema`uma`u Crater floor. The summit tiltmeter network recorded continued inflation; minor deflations accompany each back-to-back high lava stand (rise/fall or filling/draining cycles). Seismic tremor levels were elevated - each rise in lava level was accompanied by a corresponding drop in tremor amplitude followed by a strong tremor burst as lava briefly drained to a lower level.
The network of GPS receivers recorded extension across the summit mimicking the current tilt. Another unusually large number of forty-four earthquakes were strong enough to be located within Kilauea volcano - thirty-two within the upper east rift zone (most were located between Keanakako`i and Hi`iaka Craters), eight on south flank faults, two beneath the area west of the summit, one beneath Pu`u `O`o, and one within the lower east rift zone; we continue to watch the sporadicly elevated seismicity in the upper east rift zone closely.
The summit gas plume is wispy and moving to the north this morning. The most recent (preliminary) sulfur dioxide emission rate measurement was 400 tonnes/day on March 2, 2011 averaged over at least one high lava stand during which the emissions may be halved. In addition to gas, the plume wafted small amounts of ash-sized tephra, mostly bits of fresh spatter, that were deposited on nearby downwind surfaces.
Past 24 hours at the middle east rift zone vents: Lava flows from the northeast cone were inactive by noon yesterday with new lava flows starting from the northwest cone just before 5 pm. The east wall and northeast cone sources glowed overnight.
The tiltmeter on the north flank of Pu`u `O`o recorded a sharp switch to inflation at about 10:30 am yesterday followed by abrupt deflation at 4:45 pm as the northwest cone became active. The network of GPS receivers recorded extension and contraction across the cone mimicking the tilt. Seismic tremor levels near Pu`u `O`o remained low and steady. The most recent (preliminary) sulfur dioxide emission rate measurement from east rift zone vents was 300 tonnes/day on February 8, 2011; new measurements must await the return of moderate trade winds.
The two branches of the November 29 flow (1,200 ft elevation tube breach) continued to host scattered breakouts on the pali and the coastal plain. The lowest breakouts from the eastern branch continued to be active along the eastern margin of earlier flows below the 130 ft elevation (estimated) and may be an estimated 0.9 km (0.5 mi) west of the Kalapana Gardens road/highway 130 intersection.
Hazard Summary: Kalapana - active lava flows continue to threaten structures in Kalapana Gardens subdivision and adjacent areas over the coming days, weeks, or even months; the hazard is greatest for structures that are located within 300 m (985 ft) of actively inflating or advancing flows and that are topographically less than 2 m (6 ft) higher than the tops of approaching flows; any structure within these horizontal and vertical parameters could potentially be destroyed by advancing lava within 24 hours. East rift vents and flow field - near-vent areas could erupt or collapse without warning; potentially-lethal concentrations of sulfur dioxide gas are present within 1 km downwind of vent areas. Ocean Entries: lava deltas can collapse without warning, produce hot rock falls that can reach 400 m (0.25 mi) inland, as well as seaward, and produce large local scalding waves; the gas/steam plume produced by lava entering the ocean contains fine lava fragments and acid gases and droplets that can be harmful to human health at moderate distances and potentially-lethal on the delta. These rapidly changing conditions near the ocean entry have been responsible for many injuries and a few deaths. Kilauea Crater - explosive events are capable of ejecting rocks and lava several hundred meters (yards) from the Halema`uma`u vent; ash and potentially-lethal concentrations of sulfur dioxide are present within 1 km downwind.
Kalapana Public Access Information from Hawai`i County Civil Defense: Kalapana Gardens is a private subdivision and access will only be granted to subdivision residents. Private property borders highway 130 through Kalapana, and visitors to the Hawai`i County Lava Viewing Area are not allowed access off the highway easement. Hawai`i County Police will be monitoring the area. Hawai`i County Lava Viewing Area status can be found by calling 961-8093.
Maps, photos, Webcam views, and other information about Kilauea Volcano are available at http://volcanoes.usgs.gov/hvo/activity/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/activity/alertsystem/index.php
Definitions of Terms Used:
methane blast: when lava flows advance through a vegetated area, small explosions sometimes occur due to the ignition of methane gas, produced by lava-cooked plants and trapped beneath the ground surface. Injuries can occur as the result of airborne rock fragments.
rootless shields: a small mound of lava, located directly over an active lava tube that is built by repeated overflows from its top. These are rootless because they are fed from a lava tube and not from a deeper source (vent). The upper part of the TEB lava tube has numerous rootless shields built from the vent down to about the 1,500 ft elevation.
mauka, makai: Hawaiian terms for directions relative to the coast - makai (toward the coast) and mauka (away from the coast).
composite seismic events: is a seismic signal with multiple distinct phases that has been recorded frequently at HVO from the Halema`uma`u Overlook vent area since its explosive opening in March, 2008. For the composite events recorded at Halema`uma`u, we typically see an initial high frequency vibration lasting for a few seconds that have been correlated with rockfalls. This is followed by about 30 seconds of a long-period (LP) oscillation with an approximately 2- to 3-second period. The final phase of the signal is several minutes of a very-long-period (VLP) oscillation with an approximately 25- to 30-second period. The LP signals are interpreted to be from the uppermost portion of the conduit and VLP signals are interpreted to be fluid passing through a deep constriction in the conduit through which lava rises to the pond surface we see in the webcam.
high lava stands: Starting in June, 2010, lava within the Halema`uma`u Overlook vent rises 20-40 m over an interval of 10s of minutes, remains high for up to several hours, and then drains back to its previous level, while vigorously degassing, in several minutes. During the high stand, the gas plume becomes wispy, gas emissions halve in rate, and seismic tremor drops to very low levels; the high stand is followed by a strong seismic tremor burst, lasting several minutes, accompanying the draining. Many, but not all, high lava stands start with a rockfall event, some accompanied by VLP seismic energy.
Inflating surface flow: is a lava flow that may not advance but continues to thicken as its top and bottom crusts grow around a continuously replenished molten interior. This can be visualized as a large flat bladder of molten lava that could burst along its edges at any time.
Hakuma horst: a horst is an section of earth that is raised between two nearly parallel faults so that its surface is higher than the surrounding ground. The Hakuma horst is located along the coast west of Kalapana; it was responsible for diverting lava through Kalapana village in 1990 and appears to be having a similar influence on lava flows in 2010.
Halema`uma`u Overlook vent: has been difficult to describe concisely. The vent is actually a pit, or crater, in the floor of the larger Halema`uma`u Crater in the floor of the larger Kilauea caldera or crater - a crater within a crater within a crater. It is easiest to describe as a pit inset within the floor of a crater within a caldera. The pit is about 140 m (460 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at the pit floor, and is about 200 m (660 ft) deep. As of November, 2009, a lava pond surface has been visible in a hole in the floor of this pit.
glow: light from an unseen source; indirect light.
incandescence: the production of visible light from a hot surface. The term also refers to the light emitted from a hot surface. The color of the light is related to surface temperature. 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).
CD: Hawai`i County Civil Defense
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
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.
microradian: a measure of angle equivalent to 0.000057 degrees.
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 east rift eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by several hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.
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.
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 Kalapana Viewing Area status can be found at 961-8093. All times are Hawai`i Standard Time.
KILAUEA VOLCANO (CAVW #1302-01-)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE
Activity Summary for past 24 hours: DI inflation is ongoing while Kilauea volcano continued to erupt at two locations: On the east rift zone, lava flows from sources within Pu`u `O`o Crater covered much of its floor and scattered lava breakouts continued from the Nov. 29 flow near Kalapana. At the summit, the lava lake level continued to rise slowly within an eruptive vent inset within the east wall of Halema`uma`u Crater; seismicity within the upper east rift zone was elevated. Sulfur dioxide emission rates from the summit and east rift zone vents remained elevated.
Past 24 hours at Kilauea summit: The summit tiltmeter network recorded continued inflation; minor deflations accompany each back-to-back high lava stand (rise/fall or filling/draining cycles). The lava level slowly rose to about 70 m (230 ft) below the Halema`uma`u Crater floor by this morning. Seismic tremor levels were elevated - each rise in lava level was accompanied by a corresponding drop in tremor amplitude followed by a strong tremor burst as lava briefly drained to a lower level.
The network of GPS receivers recorded extension followed by contraction across the summit mimicking the tilt. An unusually large number of thirty-five earthquakes were strong enough to be located within Kilauea volcano - thirty within the upper east rift zone (Keanakako`i to Napau Craters), two within the southwest rift zone, and three on south flank faults; we continue to watch the sporadicly elevated seismicity in the upper east rift zone closely.
The summit gas plume is wispy and moving to the southwest this morning. The most recent (preliminary) sulfur dioxide emission rate measurement was 500 tonnes/day on February 22, 2011 averaged over at least one high lava stand during which the emissions may be halved; new measurements must await the return of moderate trade winds. In addition to gas, the plume wafted small amounts of ash-sized tephra, mostly bits of fresh spatter, that were deposited on nearby downwind surfaces.
Past 24 hours at the middle east rift zone vents: Lava flows started from the hole in the east crater wall around 10 am yesterday morning and advanced along the base of the crater wall; at about 10:20 pm last night, the continuous spatter from the northeast cone transitioned to a vigorous lava flow that covered the west half of the crater floor overnight.
The tiltmeter on the north flank of Pu`u `O`o recorded continued inflation until 2:45 pm; inflation resumed at 7:20 pm followed by rapid deflation at 10:20 pm last night (coincident with lava effusion from the northeast cone mentioned above). The network of GPS receivers recorded extension and contraction across the cone mimicking the tilt. Seismic tremor levels near of Pu`u `O`o remained low and steady. The most recent (preliminary) sulfur dioxide emission rate measurement from east rift zone vents was 300 tonnes/day on February 8, 2011; new measurements must await the return of moderate trade winds.
The two branches of the November 29 flow (1,200 ft elevation tube breach) continued to host scattered breakouts on the pali and the coastal plain. The lowest breakouts from the eastern branch continued to be active along the eastern margin of earlier flows below the 130 ft elevation (estimated) and may be an estimated 0.9 km (0.5 mi) west of the Kalapana Gardens road/highway 130 intersection.
Hazard Summary: Kalapana - active lava flows continue to threaten structures in Kalapana Gardens subdivision and adjacent areas over the coming days, weeks, or even months; the hazard is greatest for structures that are located within 300 m (985 ft) of actively inflating or advancing flows and that are topographically less than 2 m (6 ft) higher than the tops of approaching flows; any structure within these horizontal and vertical parameters could potentially be destroyed by advancing lava within 24 hours. East rift vents and flow field - near-vent areas could erupt or collapse without warning; potentially-lethal concentrations of sulfur dioxide gas are present within 1 km downwind of vent areas. Ocean Entries: lava deltas can collapse without warning, produce hot rock falls that can reach 400 m (0.25 mi) inland, as well as seaward, and produce large local scalding waves; the gas/steam plume produced by lava entering the ocean contains fine lava fragments and acid gases and droplets that can be harmful to human health at moderate distances and potentially-lethal on the delta. These rapidly changing conditions near the ocean entry have been responsible for many injuries and a few deaths. Kilauea Crater - explosive events are capable of ejecting rocks and lava several hundred meters (yards) from the Halema`uma`u vent; ash and potentially-lethal concentrations of sulfur dioxide are present within 1 km downwind.
Kalapana Public Access Information from Hawai`i County Civil Defense: Kalapana Gardens is a private subdivision and access will only be granted to subdivision residents. Private property borders highway 130 through Kalapana, and visitors to the Hawai`i County Lava Viewing Area are not allowed access off the highway easement. Hawai`i County Police will be monitoring the area. Hawai`i County Lava Viewing Area status can be found by calling 961-8093.
Maps, photos, Webcam views, and other information about Kilauea Volcano are available at http://volcanoes.usgs.gov/hvo/activity/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/activity/alertsystem/index.php
Definitions of Terms Used:
methane blast: when lava flows advance through a vegetated area, small explosions sometimes occur due to the ignition of methane gas, produced by lava-cooked plants and trapped beneath the ground surface. Injuries can occur as the result of airborne rock fragments.
rootless shields: a small mound of lava, located directly over an active lava tube that is built by repeated overflows from its top. These are rootless because they are fed from a lava tube and not from a deeper source (vent). The upper part of the TEB lava tube has numerous rootless shields built from the vent down to about the 1,500 ft elevation.
mauka, makai: Hawaiian terms for directions relative to the coast - makai (toward the coast) and mauka (away from the coast).
composite seismic events: is a seismic signal with multiple distinct phases that has been recorded frequently at HVO from the Halema`uma`u Overlook vent area since its explosive opening in March, 2008. For the composite events recorded at Halema`uma`u, we typically see an initial high frequency vibration lasting for a few seconds that have been correlated with rockfalls. This is followed by about 30 seconds of a long-period (LP) oscillation with an approximately 2- to 3-second period. The final phase of the signal is several minutes of a very-long-period (VLP) oscillation with an approximately 25- to 30-second period. The LP signals are interpreted to be from the uppermost portion of the conduit and VLP signals are interpreted to be fluid passing through a deep constriction in the conduit through which lava rises to the pond surface we see in the webcam.
high lava stands: Starting in June, 2010, lava within the Halema`uma`u Overlook vent rises 20-40 m over an interval of 10s of minutes, remains high for up to several hours, and then drains back to its previous level, while vigorously degassing, in several minutes. During the high stand, the gas plume becomes wispy, gas emissions halve in rate, and seismic tremor drops to very low levels; the high stand is followed by a strong seismic tremor burst, lasting several minutes, accompanying the draining. Many, but not all, high lava stands start with a rockfall event, some accompanied by VLP seismic energy.
Inflating surface flow: is a lava flow that may not advance but continues to thicken as its top and bottom crusts grow around a continuously replenished molten interior. This can be visualized as a large flat bladder of molten lava that could burst along its edges at any time.
Hakuma horst: a horst is an section of earth that is raised between two nearly parallel faults so that its surface is higher than the surrounding ground. The Hakuma horst is located along the coast west of Kalapana; it was responsible for diverting lava through Kalapana village in 1990 and appears to be having a similar influence on lava flows in 2010.
Halema`uma`u Overlook vent: has been difficult to describe concisely. The vent is actually a pit, or crater, in the floor of the larger Halema`uma`u Crater in the floor of the larger Kilauea caldera or crater - a crater within a crater within a crater. It is easiest to describe as a pit inset within the floor of a crater within a caldera. The pit is about 140 m (460 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at the pit floor, and is about 200 m (660 ft) deep. As of November, 2009, a lava pond surface has been visible in a hole in the floor of this pit.
glow: light from an unseen source; indirect light.
incandescence: the production of visible light from a hot surface. The term also refers to the light emitted from a hot surface. The color of the light is related to surface temperature. 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).
CD: Hawai`i County Civil Defense
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
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.
microradian: a measure of angle equivalent to 0.000057 degrees.
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 east rift eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by several hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.
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.
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 Kalapana Viewing Area status can be found at 961-8093. All times are Hawai`i Standard Time.
KILAUEA VOLCANO (CAVW #1302-01-)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE
Activity Summary for past 24 hours: DI inflation is ongoing while Kilauea volcano continued to erupt at two locations: On the east rift zone, spattering from sources within Pu`u `O`o Crater, glow from the TEB vent, and scattered lava breakouts continued from the Nov. 29 flow near Kalapana. At the summit, the lava lake level rose within an eruptive vent inset within the east wall of Halema`uma`u Crater. Sulfur dioxide emission rates from the summit and east rift zone vents remained elevated.
Past 24 hours at Kilauea summit: The summit tiltmeter network recorded continued inflation; minor deflations accompany each high lava stand (rise/fall or filling/draining cycles). After dropping to about 120 m (395 ft) during DI deflation, the lava level rose to 80 m (260 ft) below the Halema`uma`u Crater floor by this morning during DI inflation. Seismic tremor levels were elevated - each rise in lava level was accompanied by a corresponding drop in tremor amplitude followed by a strong tremor burst as lava drained to a lower level.
The network of GPS receivers recorded extension followed by contraction across the summit mimicking the tilt. Thirteen earthquakes were strong enough to be located within Kilauea volcano - four within the southwest rift zone, five within the upper east rift zone, and four on south flank faults.
The summit gas plume rose vertically this morning. The most recent (preliminary) sulfur dioxide emission rate measurement was 500 tonnes/day on February 22, 2011 averaged over at least one high lava stand during which the emissions may be halved; new measurements must await the return of moderate trade winds. In addition to gas, the plume wafted small amounts of ash-sized tephra, mostly bits of fresh spatter, that were deposited on nearby downwind surfaces.
Past 24 hours at the middle east rift zone vents: The Pu`u `O`o webcam recorded spattering from the hole in the east crater wall and the northeast cone overnight. The TEcam recorded glow from the TEB vent (Fissure D of the July 21, 2007 breakout).
The tiltmeter on the north flank of Pu`u `O`o recorded continued inflation. The network of GPS receivers recorded extension and contraction across the cone mimicking the tilt. Seismic tremor levels near of Pu`u `O`o remained low and steady. The most recent (preliminary) sulfur dioxide emission rate measurement from east rift zone vents was 300 tonnes/day on February 8, 2011; new measurements must await the return of moderate trade winds.
The two branches of the November 29 flow (1,200 ft elevation tube breach) continued to host scattered breakouts on the pali and the coastal plain. The lowest breakouts from the eastern branch continued to be active along the eastern margin of earlier flows below the 130 ft elevation (estimated) and may an estimated 0.9 km (0.5 mi) west of the Kalapana Gardens road/highway 130 intersection.
Hazard Summary: Kalapana - active lava flows continue to threaten structures in Kalapana Gardens subdivision and adjacent areas over the coming days, weeks, or even months; the hazard is greatest for structures that are located within 300 m (985 ft) of actively inflating or advancing flows and that are topographically less than 2 m (6 ft) higher than the tops of approaching flows; any structure within these horizontal and vertical parameters could potentially be destroyed by advancing lava within 24 hours. East rift vents and flow field - near-vent areas could erupt or collapse without warning; potentially-lethal concentrations of sulfur dioxide gas are present within 1 km downwind of vent areas. Ocean Entries: lava deltas can collapse without warning, produce hot rock falls that can reach 400 m (0.25 mi) inland, as well as seaward, and produce large local scalding waves; the gas/steam plume produced by lava entering the ocean contains fine lava fragments and acid gases and droplets that can be harmful to human health at moderate distances and potentially-lethal on the delta. These rapidly changing conditions near the ocean entry have been responsible for many injuries and a few deaths. Kilauea Crater - explosive events are capable of ejecting rocks and lava several hundred meters (yards) from the Halema`uma`u vent; ash and potentially-lethal concentrations of sulfur dioxide are present within 1 km downwind.
Kalapana Public Access Information from Hawai`i County Civil Defense: Kalapana Gardens is a private subdivision and access will only be granted to subdivision residents. Private property borders highway 130 through Kalapana, and visitors to the Hawai`i County Lava Viewing Area are not allowed access off the highway easement. Hawai`i County Police will be monitoring the area. Hawai`i County Lava Viewing Area status can be found by calling 961-8093.
Maps, photos, Webcam views, and other information about Kilauea Volcano are available at http://volcanoes.usgs.gov/hvo/activity/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/activity/alertsystem/index.php
Definitions of Terms Used:
methane blast: when lava flows advance through a vegetated area, small explosions sometimes occur due to the ignition of methane gas, produced by lava-cooked plants and trapped beneath the ground surface. Injuries can occur as the result of airborne rock fragments.
rootless shields: a small mound of lava, located directly over an active lava tube that is built by repeated overflows from its top. These are rootless because they are fed from a lava tube and not from a deeper source (vent). The upper part of the TEB lava tube has numerous rootless shields built from the vent down to about the 1,500 ft elevation.
mauka, makai: Hawaiian terms for directions relative to the coast - makai (toward the coast) and mauka (away from the coast).
composite seismic events: is a seismic signal with multiple distinct phases that has been recorded frequently at HVO from the Halema`uma`u Overlook vent area since its explosive opening in March, 2008. For the composite events recorded at Halema`uma`u, we typically see an initial high frequency vibration lasting for a few seconds that have been correlated with rockfalls. This is followed by about 30 seconds of a long-period (LP) oscillation with an approximately 2- to 3-second period. The final phase of the signal is several minutes of a very-long-period (VLP) oscillation with an approximately 25- to 30-second period. The LP signals are interpreted to be from the uppermost portion of the conduit and VLP signals are interpreted to be fluid passing through a deep constriction in the conduit through which lava rises to the pond surface we see in the webcam.
high lava stands: Starting in June, 2010, lava within the Halema`uma`u Overlook vent rises 20-40 m over an interval of 10s of minutes, remains high for up to several hours, and then drains back to its previous level, while vigorously degassing, in several minutes. During the high stand, the gas plume becomes wispy, gas emissions halve in rate, and seismic tremor drops to very low levels; the high stand is followed by a strong seismic tremor burst, lasting several minutes, accompanying the draining. Many, but not all, high lava stands start with a rockfall event, some accompanied by VLP seismic energy.
Inflating surface flow: is a lava flow that may not advance but continues to thicken as its top and bottom crusts grow around a continuously replenished molten interior. This can be visualized as a large flat bladder of molten lava that could burst along its edges at any time.
Hakuma horst: a horst is an section of earth that is raised between two nearly parallel faults so that its surface is higher than the surrounding ground. The Hakuma horst is located along the coast west of Kalapana; it was responsible for diverting lava through Kalapana village in 1990 and appears to be having a similar influence on lava flows in 2010.
Halema`uma`u Overlook vent: has been difficult to describe concisely. The vent is actually a pit, or crater, in the floor of the larger Halema`uma`u Crater in the floor of the larger Kilauea caldera or crater - a crater within a crater within a crater. It is easiest to describe as a pit inset within the floor of a crater within a caldera. The pit is about 140 m (460 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at the pit floor, and is about 200 m (660 ft) deep. As of November, 2009, a lava pond surface has been visible in a hole in the floor of this pit.
glow: light from an unseen source; indirect light.
incandescence: the production of visible light from a hot surface. The term also refers to the light emitted from a hot surface. The color of the light is related to surface temperature. 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).
CD: Hawai`i County Civil Defense
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
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.
microradian: a measure of angle equivalent to 0.000057 degrees.
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 east rift eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by several hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.
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.
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 Kalapana Viewing Area status can be found at 961-8093. All times are Hawai`i Standard Time.
KILAUEA VOLCANO (CAVW #1302-01-)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE
Activity Summary for past 24 hours: DI inflation is ongoing while Kilauea volcano continued to erupt at two locations: On the east rift zone, scattered lava breakouts continued from the Nov. 29 flow near Kalapana. At the summit, the lava lake level continued to recede within an eruptive vent inset within the east wall of Halema`uma`u Crater. Sulfur dioxide emission rates from the summit and east rift zone vents remained elevated.
Past 24 hours at Kilauea summit: The summit tiltmeter network recorded the switch to DI inflation at 11:40 pm last night; minor deflations accompanying two high lava stands (rise/fall or filling/draining cycles). The webcams monitoring the lava lake failed just before 9 pm last night so we don't have an estimate of its position. Seismic tremor levels were elevated - each rise in lava level was accompanied by a corresponding drop in tremor amplitude followed by a strong tremor burst as lava drained to a lower level.
The network of GPS receivers recorded extension followed by contraction across the summit mimicking the tilt. Four earthquakes were strong enough to be located within Kilauea volcano - one within the upper southwest rift zone and three on south flank faults.
The summit gas plume was obscured by low fog this morning. The most recent (preliminary) sulfur dioxide emission rate measurement was 400 tonnes/day on February 8, 2011 averaged over at least one high lava stand during which the emissions may be halved; new measurements must await the return of moderate trade winds. In addition to gas, the plume wafted small amounts of ash-sized tephra, mostly bits of fresh spatter, that were deposited on nearby downwind surfaces.
Past 24 hours at the middle east rift zone vents: The Pu`u `O`o webcam recorded strong glow from the hole in the east crater wall and the northeast cone overnight. There was no evidence for active lava flows within the rootless shield field after dawn yesterday.
The tiltmeter on the north flank of Pu`u `O`o recorded the switch to DI inflation at about 5 am this morning. The network of GPS receivers recorded extension and contraction across the cone mimicking the tilt. Seismic tremor levels uprift of Pu`u `O`o remained low and steady. The most recent (preliminary) sulfur dioxide emission rate measurement from east rift zone vents was 300 tonnes/day on February 8, 2011; new measurements must await the return of moderate trade winds.
The two branches of the November 29 flow (1,200 ft elevation tube breach) continued to host scattered breakouts on the pali and the coastal plain. The lowest breakouts from the eastern branch continued to be active along the eastern margin of earlier flows below the 130 ft elevation (estimated) and may be less than 1 km (0.6 mi) west of the Kalapana Gardens road/highway 130 intersection. Surprisingly, the most recent DI events have not had any obvious effect on lava activity from the Nov. 29 breakouts.
Hazard Summary: Kalapana - active lava flows continue to threaten structures in Kalapana Gardens subdivision and adjacent areas over the coming days, weeks, or even months; the hazard is greatest for structures that are located within 300 m (985 ft) of actively inflating or advancing flows and that are topographically less than 2 m (6 ft) higher than the tops of approaching flows; any structure within these horizontal and vertical parameters could potentially be destroyed by advancing lava within 24 hours. East rift vents and flow field - near-vent areas could erupt or collapse without warning; potentially-lethal concentrations of sulfur dioxide gas are present within 1 km downwind of vent areas. Ocean Entries: lava deltas can collapse without warning, produce hot rock falls that can reach 400 m (0.25 mi) inland, as well as seaward, and produce large local scalding waves; the gas/steam plume produced by lava entering the ocean contains fine lava fragments and acid gases and droplets that can be harmful to human health at moderate distances and potentially-lethal on the delta. These rapidly changing conditions near the ocean entry have been responsible for many injuries and a few deaths. Kilauea Crater - explosive events are capable of ejecting rocks and lava several hundred meters (yards) from the Halema`uma`u vent; ash and potentially-lethal concentrations of sulfur dioxide are present within 1 km downwind.
Kalapana Public Access Information from Hawai`i County Civil Defense: Kalapana Gardens is a private subdivision and access will only be granted to subdivision residents. Private property borders highway 130 through Kalapana, and visitors to the Hawai`i County Lava Viewing Area are not allowed access off the highway easement. Hawai`i County Police will be monitoring the area. Hawai`i County Lava Viewing Area status can be found by calling 961-8093.
Maps, photos, Webcam views, and other information about Kilauea Volcano are available at http://volcanoes.usgs.gov/hvo/activity/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/activity/alertsystem/index.php
Definitions of Terms Used:
methane blast: when lava flows advance through a vegetated area, small explosions sometimes occur due to the ignition of methane gas, produced by lava-cooked plants and trapped beneath the ground surface. Injuries can occur as the result of airborne rock fragments.
rootless shields: a small mound of lava, located directly over an active lava tube that is built by repeated overflows from its top. These are rootless because they are fed from a lava tube and not from a deeper source (vent). The upper part of the TEB lava tube has numerous rootless shields built from the vent down to about the 1,500 ft elevation.
mauka, makai: Hawaiian terms for directions relative to the coast - makai (toward the coast) and mauka (away from the coast).
composite seismic events: is a seismic signal with multiple distinct phases that has been recorded frequently at HVO from the Halema`uma`u Overlook vent area since its explosive opening in March, 2008. For the composite events recorded at Halema`uma`u, we typically see an initial high frequency vibration lasting for a few seconds that have been correlated with rockfalls. This is followed by about 30 seconds of a long-period (LP) oscillation with an approximately 2- to 3-second period. The final phase of the signal is several minutes of a very-long-period (VLP) oscillation with an approximately 25- to 30-second period. The LP signals are interpreted to be from the uppermost portion of the conduit and VLP signals are interpreted to be fluid passing through a deep constriction in the conduit through which lava rises to the pond surface we see in the webcam.
high lava stands: Starting in June, 2010, lava within the Halema`uma`u Overlook vent rises 20-40 m over an interval of 10s of minutes, remains high for up to several hours, and then drains back to its previous level, while vigorously degassing, in several minutes. During the high stand, the gas plume becomes wispy, gas emissions halve in rate, and seismic tremor drops to very low levels; the high stand is followed by a strong seismic tremor burst, lasting several minutes, accompanying the draining. Many, but not all, high lava stands start with a rockfall event, some accompanied by VLP seismic energy.
Inflating surface flow: is a lava flow that may not advance but continues to thicken as its top and bottom crusts grow around a continuously replenished molten interior. This can be visualized as a large flat bladder of molten lava that could burst along its edges at any time.
Hakuma horst: a horst is an section of earth that is raised between two nearly parallel faults so that its surface is higher than the surrounding ground. The Hakuma horst is located along the coast west of Kalapana; it was responsible for diverting lava through Kalapana village in 1990 and appears to be having a similar influence on lava flows in 2010.
Halema`uma`u Overlook vent: has been difficult to describe concisely. The vent is actually a pit, or crater, in the floor of the larger Halema`uma`u Crater in the floor of the larger Kilauea caldera or crater - a crater within a crater within a crater. It is easiest to describe as a pit inset within the floor of a crater within a caldera. The pit is about 140 m (460 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at the pit floor, and is about 200 m (660 ft) deep. As of November, 2009, a lava pond surface has been visible in a hole in the floor of this pit.
glow: light from an unseen source; indirect light.
incandescence: the production of visible light from a hot surface. The term also refers to the light emitted from a hot surface. The color of the light is related to surface temperature. 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).
CD: Hawai`i County Civil Defense
tonne: metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 1.1 English tons.
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.
microradian: a measure of angle equivalent to 0.000057 degrees.
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 east rift eruption site, as many of the DI events at Kilauea summit are also recorded at a tiltmeter at Pu`u `O`o, delayed by several hours. DI events often correlate with lava pulses and/or pauses in the eruption at the Pu`u `O`o/July 21/TEB vents.
More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.
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.
Update Archive
Older updates can be found using the HVO Archive Form.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 theUSGS Volcanic Activity Alert-Notification System web page.
