HVO Kilauea Status

Recent Kilauea Status Reports, Updates, and Information Releases

HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Friday, August 22, 2014 7:06 AM HST (Friday, August 22, 2014 17:06 UTC)


This report on the status of Kilauea volcanic activity, in addition to maps, photos, and Webcam images (available at http://hvo.wr.usgs.gov/activity/kilaueastatus.php), was prepared by the USGS Hawaiian Volcano Observatory (HVO). All times are Hawai`i Standard Time.

KILAUEA VOLCANO (VNUM #332010)
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: Kīlauea continued to erupt at its summit and within the East Rift Zone, and gas emissions remained elevated. Deflation at the summit slowed to a stop overnight and the lava lake level was 4550 m below the Overlook crater rim. At the middle East Rift Zone, the June 27th flow advanced to the northeast, partly confined to a large ground crack.

Recent Summit Observations: Deflation at Kīlauea's summit, which started on August 18, slowed through the day yesterday and stopped overnight. The lava lake level stopped falling as well and was 4550 m below the Overlook crater rim this morning. A swarm of long-period earthquakes beneath the summit caldera ended yesterday, and there was no other significant change in seismicity beneath Kīlauea. Seismic tremor at the summit remained low and varied with changes in spattering on the surface of the lava lake. GPS receivers spanning the summit caldera recorded about 5 cm of extension between early May and early July. Since then there has been no net extension or contraction. During the week ending on August 19, 2014, the elevated summit sulfur-dioxide emission rate was measured at 2,4005,000 tonnes/day (see caveat below), and a tiny amount of particulate material was carried aloft by the plume.

Recent East Rift Zone Observations: There was no significant change in ground tilt at Puʻu ʻŌʻō over the past day. Glow was visible overnight above several outgassing openings in Puʻu ʻŌʻō's crater floor, though that above a pit on the southeast side of the crater floor was by far the most prominent. The decrease in smoke and glow from the front of the June 27th flow over the past several days suggested that its vigor may have been declining. A helicopter flight yesterday, however, showed that the front of the flow had poured into a very large ground crack and was continuing to advance toward the northeast below ground, thus producing little smoke. The distribution of steam along the ground crack suggested that the flow front was 10.3 km from the vent (straight-line distance) at that time. Another flight is scheduled for today to confirm yesterday's preliminary finding. Surface activity also continues about midway along the length of the flow and is advancing into a different section of forest northeast of Puʻu ʻŌʻō. The most recent sulfur-dioxide emission-rate measurement for the East Rift Zone was 400 tonnes per day (from all sources) on August 18, 2014.



Sulfur Dioxide Emission Rate estimation caveat: Starting in 2014, we report the emission rate estimated by a new, more accurate method. The numbers increase by a factor of 2-4 but the actual emission rate has not changed. For more on this reporting change, please read http://hvo.wr.usgs.gov/volcanowatch/view.php?id=207

Background:
Summit The summit lava lake is within an elliptical crater (unofficially called the Overlook crater), which has dimensions of approximately 160 m (520 ft) by 210 m (690 ft), inset within the eastern portion of Halemaʻumaʻu Crater. The lake level has varied from about 25 m to more than 200 m (out of sight) below the floor of Halemaʻumaʻu Crater. The Overlook crater has been more-or-less continuously active since it opened during a small explosive event on March 19, 2008. The lake level responds to summit tilt changes with the lake generally receding during deflation and rising during inflation. During 2013 and early 2014, the lava level has been typically between 30 m (100 ft) and 60 m (200 ft) below the floor of Halemaʻumaʻu Crater. Small collapses in the Overlook crater are common, and over time have resulted in a gradual enlargement of the Overlook crater. The ambient SO2 concentrations near the vent vary greatly, but are persistently higher than 10 ppm and frequently exceed 50 ppm (upper limit of detector) during moderate trade winds. The gas plume typically includes a small amount of ash-sized tephra (mostly fresh spatter bits and Pele's hair from the circulating lava lake). The heaviest pieces are deposited onto nearby surfaces while the finer bits can be carried several kilometers before dropping out of the plume.

East Rift Zone vents and flow field The eruption in Kīlauea's middle East Rift Zone started with a fissure eruption on January 3, 1983, and continued with few interruptions at Puʻu ʻŌʻō Cone, or temporarily from vents within a few kilometers to the east or west. A fissure eruption on the upper east flank of Puʻu ʻŌʻō Cone on Sept. 21, 2011, drained the lava lakes and fed a lava flow (Peace Day flow) that advanced southeast through the abandoned Royal Gardens subdivision to the ocean within Hawaiʻi Volcanoes National Park in early December 2011. The flows stalled and re-entered the ocean starting on November 24, 2012, until activity started to decline and the ocean entry ceased in August 20, 2013; the flow was dead by early November, 2013. The Kahaualeʻa flow, which started from the spatter cone/lava lake at the northeast edge of the Puʻu ʻŌʻō crater floor in mid-January 2013 was dead by late April, but a new flow (informally called Kahaualeʻa 2) became active in the same area in early May 2013, waxing with inflation and waning with deflation. The Kahaualeʻa 2 flow died following the onset of a new breakout from the northeast flank of Puʻu ʻŌʻō on June 27, 2014. The June 27th flow continues to advance toward the northeast.

Hazard Summary:
East Rift Zone vents and flow field Lava flows from the June 27 breakout pose no immediate threat to residential areas. Near-vent areas could erupt or collapse without warning with spatter and/or ash being wafted within the gas plume. In addition, potentially-lethal concentrations of sulfur dioxide gas may be present within 1 km downwind of vent areas. Active lava flows within forested areas can produce methane blasts capable of propelling rocks and other debris into the air. All recently active lava flows are within Hawaiʻi Volcanoes National Park and adjacent State land managed by the Department of Land and Natural Resources or the Office of Hawaiian Affairs.

Kīlauea Crater Ash and Pele's hair can be carried several kilometers downwind, and potentially-lethal concentrations of sulfur dioxide can be present within 1 km downwind.

Viewing Summary:
East Rift Zone flow field Most of the flow field is within the closed-access Kahaualeʻa Natural Area Reserve (NAR) or the Wao Kele o Puna Forest Reserve (DLNR, OHA) and can only be viewed from the air. Under favorable weather conditions at night, distant glow from the active flows can be seen from the County Viewing Area at Kalapana (Lava hotline 961-8093) and from the end of the Chain of Craters Road and a few other areas within Hawaiʻi Volcanoes National Park.

Puʻu ʻŌʻō Cone and Kīlauea Crater These areas are within Hawaiʻi Volcanoes National Park; Park access and viewing information can be found at http://www.nps.gov/havo/planyourvisit/lava2.htm.

Definitions of Terms Used:

ash: tephra less than 2 mm (5/64 inches) in size.

CD: Hawai`i County Civil Defense

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.

DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a geophysical event of uncertain volcanic 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 (weak DI events) to 2-3 days (strong DI events) 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/Peace Day vents.

glow: light from an unseen source; indirect light.

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 which is, in turn, 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 160 m (525 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at a depth of 200 m (660 ft) below the Halema`uma`u Crater floor. From November, 2009, to now, a lava pond surface has been visible in this pit.

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).

LPs: - Long Period (LP) events refer to earthquakes that have a lower frequency or tone than typical earthquakes and are usually attributed to the resonance of fluid- and gas-filled conduits, cracks and/or chambers. Because of their association with fluids and gases, LP earthquakes in the vicinity of volcanoes can be useful for monitoring purposes. At other volcanoes LP earthquakes are also known as low-frequency earthquakes, tornillos or B-type earthquakes.

mauka, makai: Hawaiian terms for directions relative to the coast - makai or ma kai (toward the coast) and mauka or ma uka (toward the highlands or away from the coast).

microradian: a measure of angle equivalent to 0.000057 degrees.

pali: Hawaiian term for cliff or precipice.

rise/fall events: one of the episodic behaviors exhibited by the summit lava lake starting in 2009. An event starts with a rise in lava level, a decrease in high-frequency summit tremor amplitude, a decrease or total stoppage of spattering, and a small decrease in tilt. After a period of minutes to hours, the lava will abruptly drain back to its previous level amidst resumed vigorous spattering, seismic tremor amplitude will increase for a short time (a seismic tremor burst) before resuming background levels, and summit tilt will return to its previous level. Gas emissions decrease significantly during the high lava stand (the plume gets wispy), and resume during its draining phase. Taken together, the geophysical characteristics suggest that, during the high lava stand, lava is puffed up with gas trapped under the lava lake crust.

seismic tremor dropout: these behaviors are identical to rise/fall events except that the lava lake level doesn't rise or fall significantly. High-frequency seismic tremor, gas emissions, and spattering decrease abruptly during a dropout. A dropout can end with a burst of seismic tremor and a significant pulse of gas emissions.

tephra: all material deposited by fallout from an eruption-related plume, regardless of size.

tonne (t): metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 0.984 English tons.

More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.

Additional Information:
For a definition of volcano alert levels and aviation color codes: http://volcanoes.usgs.gov/activity/alertsystem/index.php

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://hvo.wr.usgs.gov/seismic/volcweb/earthquakes/

HVO Contact Information: askHVO@usgs.gov

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



HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Thursday, August 21, 2014 8:53 AM HST (Thursday, August 21, 2014 18:53 UTC)


This report on the status of Kilauea volcanic activity, in addition to maps, photos, and Webcam images (available at http://hvo.wr.usgs.gov/activity/kilaueastatus.php), was prepared by the USGS Hawaiian Volcano Observatory (HVO). All times are Hawai`i Standard Time.

KILAUEA VOLCANO (VNUM #332010)
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: Kīlauea continued to erupt at its summit and within the East Rift Zone, and gas emissions remained elevated. The summit deflated gradually and the lava lake level fell slightly. At the middle East Rift Zone, the June 27th flow advanced through forest northeast and east-northeast of the vent.

Recent Summit Observations: Gradual deflation at Kīlauea's summit, which started on August 18, continued over the past day. The lava lake level dropped as well and was around 45 m below the Overlook crater rim this morning. A swarm of long-period earthquakes ~8 km beneath the summit caldera started yesterday and is ongoing. There was also a group of at least 5 earthquakes near Mauna Ulu on the upper East Rift Zone. Seismic tremor at the summit remained low and varied with changes in spattering on the surface of the lava lake. GPS receivers spanning the summit caldera recorded about 5 cm of extension between early May and early July. Since then there has been no net extension or contraction. During the week ending on August 19, 2014, the elevated summit sulfur-dioxide emission rate was measured at 2,4005,000 tonnes/day (see caveat below), and a tiny amount of particulate material was carried aloft by the plume.

Recent East Rift Zone Observations: There was net deflation at Puʻu ʻŌʻō through the day yesterday, but heavy rainfall last night obscures any subsequent ground tilt signal. Glow was visible overnight above several outgassing openings in Puʻu ʻŌʻō's crater floor and at skylights along the upper part of the June-27th flow lava tube. The June-27th flow continued to advance through forest east-northeast of Puʻu ʻŌʻō, and was 9.4 km from the vent (straight-line distance) on August 18, based on satellite imagery. The vigor of this part of the flow appears to have diminished over the past several days, as surface activity about midway along the length of the flow increased. This activity midway along the flow is advancing into a different section of forest northeast of Puʻu ʻŌʻō. The most recent sulfur-dioxide emission-rate measurement for the East Rift Zone was 400 tonnes per day (from all sources) on August 18, 2014.



Sulfur Dioxide Emission Rate estimation caveat: Starting in 2014, we report the emission rate estimated by a new, more accurate method. The numbers increase by a factor of 2-4 but the actual emission rate has not changed. For more on this reporting change, please read http://hvo.wr.usgs.gov/volcanowatch/view.php?id=207

Background:
Summit The summit lava lake is within an elliptical crater (unofficially called the Overlook crater), which has dimensions of approximately 160 m (520 ft) by 210 m (690 ft), inset within the eastern portion of Halemaʻumaʻu Crater. The lake level has varied from about 25 m to more than 200 m (out of sight) below the floor of Halemaʻumaʻu Crater. The Overlook crater has been more-or-less continuously active since it opened during a small explosive event on March 19, 2008. The lake level responds to summit tilt changes with the lake generally receding during deflation and rising during inflation. During 2013 and early 2014, the lava level has been typically between 30 m (100 ft) and 60 m (200 ft) below the floor of Halemaʻumaʻu Crater. Small collapses in the Overlook crater are common, and over time have resulted in a gradual enlargement of the Overlook crater. The ambient SO2 concentrations near the vent vary greatly, but are persistently higher than 10 ppm and frequently exceed 50 ppm (upper limit of detector) during moderate trade winds. The gas plume typically includes a small amount of ash-sized tephra (mostly fresh spatter bits and Pele's hair from the circulating lava lake). The heaviest pieces are deposited onto nearby surfaces while the finer bits can be carried several kilometers before dropping out of the plume.

East Rift Zone vents and flow field The eruption in Kīlauea's middle East Rift Zone started with a fissure eruption on January 3, 1983, and continued with few interruptions at Puʻu ʻŌʻō Cone, or temporarily from vents within a few kilometers to the east or west. A fissure eruption on the upper east flank of Puʻu ʻŌʻō Cone on Sept. 21, 2011, drained the lava lakes and fed a lava flow (Peace Day flow) that advanced southeast through the abandoned Royal Gardens subdivision to the ocean within Hawaiʻi Volcanoes National Park in early December 2011. The flows stalled and re-entered the ocean starting on November 24, 2012, until activity started to decline and the ocean entry ceased in August 20, 2013; the flow was dead by early November, 2013. The Kahaualeʻa flow, which started from the spatter cone/lava lake at the northeast edge of the Puʻu ʻŌʻō crater floor in mid-January 2013 was dead by late April, but a new flow (informally called Kahaualeʻa 2) became active in the same area in early May 2013, waxing with inflation and waning with deflation. The Kahaualeʻa 2 flow died following the onset of a new breakout from the northeast flank of Puʻu ʻŌʻō on June 27, 2014.

Hazard Summary:
East Rift Zone vents and flow field Lava flows from the June 27 breakout pose no immediate threat to residential areas. Near-vent areas could erupt or collapse without warning with spatter and/or ash being wafted within the gas plume. In addition, potentially-lethal concentrations of sulfur dioxide gas may be present within 1 km downwind of vent areas. Active lava flows within forested areas can produce methane blasts capable of propelling rocks and other debris into the air. All recently active lava flows are within Hawaiʻi Volcanoes National Park and adjacent State land managed by the Department of Land and Natural Resources or the Office of Hawaiian Affairs.

Kīlauea Crater Ash and Pele's hair can be carried several kilometers downwind, and potentially-lethal concentrations of sulfur dioxide can be present within 1 km downwind.

Viewing Summary:
East Rift Zone flow field Most of the flow field is within the closed-access Kahaualeʻa Natural Area Reserve (NAR) or the Wao Kele o Puna Forest Reserve (DLNR, OHA) and can only be viewed from the air. Under favorable weather conditions at night, distant glow from the active flows can be seen from the County Viewing Area at Kalapana (Lava hotline 961-8093) and from the end of the Chain of Craters Road and a few other areas within Hawaiʻi Volcanoes National Park.

Puʻu ʻŌʻō Cone and Kīlauea Crater These areas are within Hawaiʻi Volcanoes National Park; Park access and viewing information can be found at http://www.nps.gov/havo/planyourvisit/lava2.htm.

Definitions of Terms Used:

ash: tephra less than 2 mm (5/64 inches) in size.

CD: Hawai`i County Civil Defense

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.

DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a geophysical event of uncertain volcanic 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 (weak DI events) to 2-3 days (strong DI events) 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/Peace Day vents.

glow: light from an unseen source; indirect light.

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 which is, in turn, 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 160 m (525 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at a depth of 200 m (660 ft) below the Halema`uma`u Crater floor. From November, 2009, to now, a lava pond surface has been visible in this pit.

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).

LPs: - Long Period (LP) events refer to earthquakes that have a lower frequency or tone than typical earthquakes and are usually attributed to the resonance of fluid- and gas-filled conduits, cracks and/or chambers. Because of their association with fluids and gases, LP earthquakes in the vicinity of volcanoes can be useful for monitoring purposes. At other volcanoes LP earthquakes are also known as low-frequency earthquakes, tornillos or B-type earthquakes.

mauka, makai: Hawaiian terms for directions relative to the coast - makai or ma kai (toward the coast) and mauka or ma uka (toward the highlands or away from the coast).

microradian: a measure of angle equivalent to 0.000057 degrees.

pali: Hawaiian term for cliff or precipice.

rise/fall events: one of the episodic behaviors exhibited by the summit lava lake starting in 2009. An event starts with a rise in lava level, a decrease in high-frequency summit tremor amplitude, a decrease or total stoppage of spattering, and a small decrease in tilt. After a period of minutes to hours, the lava will abruptly drain back to its previous level amidst resumed vigorous spattering, seismic tremor amplitude will increase for a short time (a seismic tremor burst) before resuming background levels, and summit tilt will return to its previous level. Gas emissions decrease significantly during the high lava stand (the plume gets wispy), and resume during its draining phase. Taken together, the geophysical characteristics suggest that, during the high lava stand, lava is puffed up with gas trapped under the lava lake crust.

seismic tremor dropout: these behaviors are identical to rise/fall events except that the lava lake level doesn't rise or fall significantly. High-frequency seismic tremor, gas emissions, and spattering decrease abruptly during a dropout. A dropout can end with a burst of seismic tremor and a significant pulse of gas emissions.

tephra: all material deposited by fallout from an eruption-related plume, regardless of size.

tonne (t): metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 0.984 English tons.

More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.

Additional Information:
For a definition of volcano alert levels and aviation color codes: http://volcanoes.usgs.gov/activity/alertsystem/index.php

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://hvo.wr.usgs.gov/seismic/volcweb/earthquakes/

HVO Contact Information: askHVO@usgs.gov

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



HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Wednesday, August 20, 2014 8:16 AM HST (Wednesday, August 20, 2014 18:16 UTC)


This report on the status of Kilauea volcanic activity, in addition to maps, photos, and Webcam images (available at http://hvo.wr.usgs.gov/activity/kilaueastatus.php), was prepared by the USGS Hawaiian Volcano Observatory (HVO). All times are Hawai`i Standard Time.

KILAUEA VOLCANO (VNUM #332010)
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: Kīlauea continued to erupt at its summit and within the East Rift Zone, and gas emissions remained elevated. The summit deflated gradually and the lava lake level fell slightly. At the middle East Rift Zone, the front of the June 27th flow advanced through forest northeast and east-northeast of the vent.

Recent Summit Observations: Gradual deflation continued at Kīlauea's summit over the past day, but slowed overnight. The lava lake level dropped as well and was 4045 m below the Overlook crater rim this morning. There was no major change in seismicity on Kīlauea; seismic tremor at the summit remained low and varied with changes in spattering on the surface of the lava lake. GPS receivers spanning the summit caldera recorded about 5 cm of extension between early May and early July. Since then there has been no net extension or contraction. During the week ending on August 12, 2014, the elevated summit sulfur-dioxide emission rate was measured at 5,100 tonnes/day (see caveat below), and a tiny amount of particulate material was carried aloft by the plume.

Recent East Rift Zone Observations: Puʻu ʻŌʻō deflated gradually over the last 24 hours. Glow was visible overnight above several outgassing openings in Puʻu ʻŌʻō's crater floor and at skylights along the June 27th flow lava tube. The June 27th flow continued to advance through forest northeast and east-northeast of Puʻu ʻŌʻō. The distal tip of the flow was 9.4 km from the vent (straight-line distance) on August 18, based on satellite imagery. Webcam imagery also shows a broad area of breakouts mid-way along the length of the flow. The most recent sulfur-dioxide emission-rate measurement was 400 tonnes per day (from all East Rift Zone sources) on August 18, 2014.



Sulfur Dioxide Emission Rate estimation caveat: Starting in 2014, we report the emission rate estimated by a new, more accurate method. The numbers increase by a factor of 2-4 but the actual emission rate has not changed. For more on this reporting change, please read http://hvo.wr.usgs.gov/volcanowatch/view.php?id=207

Background:
Summit The summit lava lake is within an elliptical crater (unofficially called the Overlook crater), which has dimensions of approximately 160 m (520 ft) by 210 m (690 ft), inset within the eastern portion of Halemaʻumaʻu Crater. The lake level has varied from about 25 m to more than 200 m (out of sight) below the floor of Halemaʻumaʻu Crater. The Overlook crater has been more-or-less continuously active since it opened during a small explosive event on March 19, 2008. The lake level responds to summit tilt changes with the lake generally receding during deflation and rising during inflation. During 2013 and early 2014, the lava level has been typically between 30 m (100 ft) and 60 m (200 ft) below the floor of Halemaʻumaʻu Crater. Small collapses in the Overlook crater are common, and over time have resulted in a gradual enlargement of the Overlook crater. The ambient SO2 concentrations near the vent vary greatly, but are persistently higher than 10 ppm and frequently exceed 50 ppm (upper limit of detector) during moderate trade winds. The gas plume typically includes a small amount of ash-sized tephra (mostly fresh spatter bits and Pele's hair from the circulating lava lake). The heaviest pieces are deposited onto nearby surfaces while the finer bits can be carried several kilometers before dropping out of the plume.

East Rift Zone vents and flow field The eruption in Kīlauea's middle East Rift Zone started with a fissure eruption on January 3, 1983, and continued with few interruptions at Puʻu ʻŌʻō Cone, or temporarily from vents within a few kilometers to the east or west. A fissure eruption on the upper east flank of Puʻu ʻŌʻō Cone on Sept. 21, 2011, drained the lava lakes and fed a lava flow (Peace Day flow) that advanced southeast through the abandoned Royal Gardens subdivision to the ocean within Hawaiʻi Volcanoes National Park in early December 2011. The flows stalled and re-entered the ocean starting on November 24, 2012, until activity started to decline and the ocean entry ceased in August 20, 2013; the flow was dead by early November, 2013. The Kahaualeʻa flow, which started from the spatter cone/lava lake at the northeast edge of the Puʻu ʻŌʻō crater floor in mid-January 2013 was dead by late April, but a new flow (informally called Kahaualeʻa 2) became active in the same area in early May 2013, waxing with inflation and waning with deflation. The Kahaualeʻa 2 flow died following the onset of a new breakout from the northeast flank of Puʻu ʻŌʻō on June 27, 2014.

Hazard Summary:
East Rift Zone vents and flow field Lava flows from the June 27 breakout pose no immediate threat to residential areas. Near-vent areas could erupt or collapse without warning with spatter and/or ash being wafted within the gas plume. In addition, potentially-lethal concentrations of sulfur dioxide gas may be present within 1 km downwind of vent areas. Active lava flows within forested areas can produce methane blasts capable of propelling rocks and other debris into the air. All recently active lava flows are within Hawaiʻi Volcanoes National Park and adjacent State land managed by the Department of Land and Natural Resources or the Office of Hawaiian Affairs.

Kīlauea Crater Ash and Pele's hair can be carried several kilometers downwind, and potentially-lethal concentrations of sulfur dioxide can be present within 1 km downwind.

Viewing Summary:
East Rift Zone flow field Most of the flow field is within the closed-access Kahaualeʻa Natural Area Reserve (NAR) or the Wao Kele o Puna Forest Reserve (DLNR, OHA) and can only be viewed from the air. Under favorable weather conditions at night, distant glow from the active flows can be seen from the County Viewing Area at Kalapana (Lava hotline 961-8093) and from the end of the Chain of Craters Road and a few other areas within Hawaiʻi Volcanoes National Park.

Puʻu ʻŌʻō Cone and Kīlauea Crater These areas are within Hawaiʻi Volcanoes National Park; Park access and viewing information can be found at http://www.nps.gov/havo/planyourvisit/lava2.htm.

Definitions of Terms Used:

ash: tephra less than 2 mm (5/64 inches) in size.

CD: Hawai`i County Civil Defense

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.

DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a geophysical event of uncertain volcanic 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 (weak DI events) to 2-3 days (strong DI events) 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/Peace Day vents.

glow: light from an unseen source; indirect light.

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 which is, in turn, 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 160 m (525 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at a depth of 200 m (660 ft) below the Halema`uma`u Crater floor. From November, 2009, to now, a lava pond surface has been visible in this pit.

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).

LPs: - Long Period (LP) events refer to earthquakes that have a lower frequency or tone than typical earthquakes and are usually attributed to the resonance of fluid- and gas-filled conduits, cracks and/or chambers. Because of their association with fluids and gases, LP earthquakes in the vicinity of volcanoes can be useful for monitoring purposes. At other volcanoes LP earthquakes are also known as low-frequency earthquakes, tornillos or B-type earthquakes.

mauka, makai: Hawaiian terms for directions relative to the coast - makai or ma kai (toward the coast) and mauka or ma uka (toward the highlands or away from the coast).

microradian: a measure of angle equivalent to 0.000057 degrees.

pali: Hawaiian term for cliff or precipice.

rise/fall events: one of the episodic behaviors exhibited by the summit lava lake starting in 2009. An event starts with a rise in lava level, a decrease in high-frequency summit tremor amplitude, a decrease or total stoppage of spattering, and a small decrease in tilt. After a period of minutes to hours, the lava will abruptly drain back to its previous level amidst resumed vigorous spattering, seismic tremor amplitude will increase for a short time (a seismic tremor burst) before resuming background levels, and summit tilt will return to its previous level. Gas emissions decrease significantly during the high lava stand (the plume gets wispy), and resume during its draining phase. Taken together, the geophysical characteristics suggest that, during the high lava stand, lava is puffed up with gas trapped under the lava lake crust.

seismic tremor dropout: these behaviors are identical to rise/fall events except that the lava lake level doesn't rise or fall significantly. High-frequency seismic tremor, gas emissions, and spattering decrease abruptly during a dropout. A dropout can end with a burst of seismic tremor and a significant pulse of gas emissions.

tephra: all material deposited by fallout from an eruption-related plume, regardless of size.

tonne (t): metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 0.984 English tons.

More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.

Additional Information:
For a definition of volcano alert levels and aviation color codes: http://volcanoes.usgs.gov/activity/alertsystem/index.php

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://hvo.wr.usgs.gov/seismic/volcweb/earthquakes/

HVO Contact Information: askHVO@usgs.gov

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



HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Tuesday, August 19, 2014 8:40 AM HST (Tuesday, August 19, 2014 18:40 UTC)


This report on the status of Kilauea volcanic activity, in addition to maps, photos, and Webcam images (available at http://hvo.wr.usgs.gov/activity/kilaueastatus.php), was prepared by the USGS Hawaiian Volcano Observatory (HVO). All times are Hawai`i Standard Time.

KILAUEA VOLCANO (VNUM #332010)
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: Kīlauea continued to erupt at its summit and within the East Rift Zone, and gas emissions remained elevated. The summit deflated gradually over the past day and the lava lake level fell slightly. At the middle East Rift Zone, the front of the June 27th flow continued to advance into forest east-northeast of the vent, but most surface activity was scattered mid-way along the flow's length.

Recent Summit Observations: Kīlauea's summit deflated gradually over the past day. The lava lake level dropped a few meters and was 3540 m below the Overlook crater rim this morning. There was no major change in seismicity on Kīlauea; seismic tremor at the summit remained low and varied with changes in spattering on the surface of the lava lake. GPS receivers spanning the summit caldera recorded about 5 cm of extension between early May and early July. Since then there has been no net extension or contraction. During the week ending on August 12, 2014, the elevated summit sulfur-dioxide emission rate was measured at 5,100 tonnes/day (see caveat below), and a tiny amount of particulate material was carried aloft by the plume.

Recent East Rift Zone Observations: Puʻu ʻŌʻō deflated gradually over the last 24 hours. Glow was visible overnight above outgassing openings in Puʻu ʻŌʻō's crater floor and at skylights along the June 27th flow lava tube. The June 27th flow continued to advance into forest east-northeast of Puʻu ʻŌʻō. The distal tip of the flow was 9.4 km from the vent (straight-line distance) on August 18, based on satellite imagery. Webcam imagery suggests, however, that the majority of surface activity is in a broad area of breakouts mid-way along the length of the flow. Some of these breakouts were advancing into a different section of forest about 5 km northeast of the vent. The most recent sulfur-dioxide emission-rate measurement was 400 tonnes per day (from all East Rift Zone sources) on August 18, 2014.



Sulfur Dioxide Emission Rate estimation caveat: Starting in 2014, we report the emission rate estimated by a new, more accurate method. The numbers increase by a factor of 2-4 but the actual emission rate has not changed. For more on this reporting change, please read http://hvo.wr.usgs.gov/volcanowatch/view.php?id=207

Background:
Summit The summit lava lake is within an elliptical crater (unofficially called the Overlook crater), which has dimensions of approximately 160 m (520 ft) by 210 m (690 ft), inset within the eastern portion of Halemaʻumaʻu Crater. The lake level has varied from about 25 m to more than 200 m (out of sight) below the floor of Halemaʻumaʻu Crater. The Overlook crater has been more-or-less continuously active since it opened during a small explosive event on March 19, 2008. The lake level responds to summit tilt changes with the lake generally receding during deflation and rising during inflation. During 2013 and early 2014, the lava level has been typically between 30 m (100 ft) and 60 m (200 ft) below the floor of Halemaʻumaʻu Crater. Small collapses in the Overlook crater are common, and over time have resulted in a gradual enlargement of the Overlook crater. The ambient SO2 concentrations near the vent vary greatly, but are persistently higher than 10 ppm and frequently exceed 50 ppm (upper limit of detector) during moderate trade winds. The gas plume typically includes a small amount of ash-sized tephra (mostly fresh spatter bits and Pele's hair from the circulating lava lake). The heaviest pieces are deposited onto nearby surfaces while the finer bits can be carried several kilometers before dropping out of the plume.

East Rift Zone vents and flow field The eruption in Kīlauea's middle East Rift Zone started with a fissure eruption on January 3, 1983, and continued with few interruptions at Puʻu ʻŌʻō Cone, or temporarily from vents within a few kilometers to the east or west. A fissure eruption on the upper east flank of Puʻu ʻŌʻō Cone on Sept. 21, 2011, drained the lava lakes and fed a lava flow (Peace Day flow) that advanced southeast through the abandoned Royal Gardens subdivision to the ocean within Hawaiʻi Volcanoes National Park in early December 2011. The flows stalled and re-entered the ocean starting on November 24, 2012, until activity started to decline and the ocean entry ceased in August 20, 2013; the flow was dead by early November, 2013. The Kahaualeʻa flow, which started from the spatter cone/lava lake at the northeast edge of the Puʻu ʻŌʻō crater floor in mid-January 2013 was dead by late April, but a new flow (informally called Kahaualeʻa 2) became active in the same area in early May 2013, waxing with inflation and waning with deflation. The Kahaualeʻa 2 flow died following the onset of a new breakout from the northeast flank of Puʻu ʻŌʻō on June 27, 2014.

Hazard Summary:
East Rift Zone vents and flow field Lava flows from the June 27 breakout pose no immediate threat to residential areas. Near-vent areas could erupt or collapse without warning with spatter and/or ash being wafted within the gas plume. In addition, potentially-lethal concentrations of sulfur dioxide gas may be present within 1 km downwind of vent areas. Active lava flows within forested areas can produce methane blasts capable of propelling rocks and other debris into the air. All recently active lava flows are within Hawaiʻi Volcanoes National Park and adjacent State land managed by the Department of Land and Natural Resources or the Office of Hawaiian Affairs.

Kīlauea Crater Ash and Pele's hair can be carried several kilometers downwind, and potentially-lethal concentrations of sulfur dioxide can be present within 1 km downwind.

Viewing Summary:
East Rift Zone flow field Most of the flow field is within the closed-access Kahaualeʻa Natural Area Reserve (NAR) or the Wao Kele o Puna Forest Reserve (DLNR, OHA) and can only be viewed from the air. Under favorable weather conditions at night, distant glow from the active flows can be seen from the County Viewing Area at Kalapana (Lava hotline 961-8093) and from the end of the Chain of Craters Road and a few other areas within Hawaiʻi Volcanoes National Park.

Puʻu ʻŌʻō Cone and Kīlauea Crater These areas are within Hawaiʻi Volcanoes National Park; Park access and viewing information can be found at http://www.nps.gov/havo/planyourvisit/lava2.htm.

Definitions of Terms Used:

ash: tephra less than 2 mm (5/64 inches) in size.

CD: Hawai`i County Civil Defense

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.

DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a geophysical event of uncertain volcanic 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 (weak DI events) to 2-3 days (strong DI events) 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/Peace Day vents.

glow: light from an unseen source; indirect light.

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 which is, in turn, 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 160 m (525 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at a depth of 200 m (660 ft) below the Halema`uma`u Crater floor. From November, 2009, to now, a lava pond surface has been visible in this pit.

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).

LPs: - Long Period (LP) events refer to earthquakes that have a lower frequency or tone than typical earthquakes and are usually attributed to the resonance of fluid- and gas-filled conduits, cracks and/or chambers. Because of their association with fluids and gases, LP earthquakes in the vicinity of volcanoes can be useful for monitoring purposes. At other volcanoes LP earthquakes are also known as low-frequency earthquakes, tornillos or B-type earthquakes.

mauka, makai: Hawaiian terms for directions relative to the coast - makai or ma kai (toward the coast) and mauka or ma uka (toward the highlands or away from the coast).

microradian: a measure of angle equivalent to 0.000057 degrees.

pali: Hawaiian term for cliff or precipice.

rise/fall events: one of the episodic behaviors exhibited by the summit lava lake starting in 2009. An event starts with a rise in lava level, a decrease in high-frequency summit tremor amplitude, a decrease or total stoppage of spattering, and a small decrease in tilt. After a period of minutes to hours, the lava will abruptly drain back to its previous level amidst resumed vigorous spattering, seismic tremor amplitude will increase for a short time (a seismic tremor burst) before resuming background levels, and summit tilt will return to its previous level. Gas emissions decrease significantly during the high lava stand (the plume gets wispy), and resume during its draining phase. Taken together, the geophysical characteristics suggest that, during the high lava stand, lava is puffed up with gas trapped under the lava lake crust.

seismic tremor dropout: these behaviors are identical to rise/fall events except that the lava lake level doesn't rise or fall significantly. High-frequency seismic tremor, gas emissions, and spattering decrease abruptly during a dropout. A dropout can end with a burst of seismic tremor and a significant pulse of gas emissions.

tephra: all material deposited by fallout from an eruption-related plume, regardless of size.

tonne (t): metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 0.984 English tons.

More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.

Additional Information:
For a definition of volcano alert levels and aviation color codes: http://volcanoes.usgs.gov/activity/alertsystem/index.php

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://hvo.wr.usgs.gov/seismic/volcweb/earthquakes/

HVO Contact Information: askHVO@usgs.gov

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



HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Monday, August 18, 2014 8:46 AM HST (Monday, August 18, 2014 18:46 UTC)


This report on the status of Kilauea volcanic activity, in addition to maps, photos, and Webcam images (available at http://hvo.wr.usgs.gov/activity/kilaueastatus.php), was prepared by the USGS Hawaiian Volcano Observatory (HVO). All times are Hawai`i Standard Time.

KILAUEA VOLCANO (VNUM #332010)
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: Kīlauea continued to erupt at its summit and within the East Rift Zone, and gas emissions remained elevated. At the summit, there was minor net deflation over the past day with slight fluctuations in lava level. At the middle East Rift Zone, the front of the June 27th flow continued to advance east-northeast.

Recent Summit Observations: Kīlauea's summit experienced minor fluctuations in ground tilt over the past day, with overall minor net deflation. The lava lake level also fluctuated slightly, due mostly to variations in spattering and outgassing, and was roughly 35 m below the Overlook crater rim. There was no major change in seismicity on Kīlauea, and seismic tremor was low and varied with changes in spattering on the surface of the lava lake. GPS receivers spanning the summit caldera recorded about 5 cm of extension between early May and early July. Since then there has been no net extension or contraction. During the week ending on August 12, 2014, the elevated summit sulfur-dioxide emission rate was measured at 5,100 tonnes/day (see caveat below), and a tiny amount of particulate material was carried aloft by the plume.

Recent East Rift Zone Observations: There was no significant change in ground tilt at Puʻu ʻŌʻō during the last 24 hours. Glow was visible overnight above outgassing pits on the northeast, south, and southeast edges of Puʻu ʻŌʻō's crater floor. The June 27th flow continued to advance into forest east-northeast of Puʻu ʻŌʻō. The tube-fed flow slowed and widened over the past several days, and its distal tip was 9.0 km from the vent (straight-line distance) on August 15. The flow also hosted a broad area of breakouts mid-way along its length that reached the forest about 5 km northeast of the vent, on the north side of the current flow. The most recent sulfur-dioxide emission-rate measurement was 600 tonnes per day (from all East Rift Zone sources) on July 31, 2014.



Sulfur Dioxide Emission Rate estimation caveat: Starting in 2014, we report the emission rate estimated by a new, more accurate method. The numbers increase by a factor of 2-4 but the actual emission rate has not changed. For more on this reporting change, please read http://hvo.wr.usgs.gov/volcanowatch/view.php?id=207

Background:
Summit The summit lava lake is within an elliptical crater (unofficially called the Overlook crater), which has dimensions of approximately 160 m (520 ft) by 210 m (690 ft), inset within the eastern portion of Halemaʻumaʻu Crater. The lake level has varied from about 25 m to more than 200 m (out of sight) below the floor of Halemaʻumaʻu Crater. The Overlook crater has been more-or-less continuously active since it opened during a small explosive event on March 19, 2008. The lake level responds to summit tilt changes with the lake generally receding during deflation and rising during inflation. During 2013 and early 2014, the lava level has been typically between 30 m (100 ft) and 60 m (200 ft) below the floor of Halemaʻumaʻu Crater. Small collapses in the Overlook crater are common, and over time have resulted in a gradual enlargement of the Overlook crater. The ambient SO2 concentrations near the vent vary greatly, but are persistently higher than 10 ppm and frequently exceed 50 ppm (upper limit of detector) during moderate trade winds. The gas plume typically includes a small amount of ash-sized tephra (mostly fresh spatter bits and Pele's hair from the circulating lava lake). The heaviest pieces are deposited onto nearby surfaces while the finer bits can be carried several kilometers before dropping out of the plume.

East Rift Zone vents and flow field The eruption in Kīlauea's middle East Rift Zone started with a fissure eruption on January 3, 1983, and continued with few interruptions at Puʻu ʻŌʻō Cone, or temporarily from vents within a few kilometers to the east or west. A fissure eruption on the upper east flank of Puʻu ʻŌʻō Cone on Sept. 21, 2011, drained the lava lakes and fed a lava flow (Peace Day flow) that advanced southeast through the abandoned Royal Gardens subdivision to the ocean within Hawaiʻi Volcanoes National Park in early December 2011. The flows stalled and re-entered the ocean starting on November 24, 2012, until activity started to decline and the ocean entry ceased in August 20, 2013; the flow was dead by early November, 2013. The Kahaualeʻa flow, which started from the spatter cone/lava lake at the northeast edge of the Puʻu ʻŌʻō crater floor in mid-January 2013 was dead by late April, but a new flow (informally called Kahaualeʻa 2) became active in the same area in early May 2013, waxing with inflation and waning with deflation. The Kahaualeʻa 2 flow died following the onset of a new breakout from the northeast flank of Puʻu ʻŌʻō on June 27, 2014.

Hazard Summary:
East Rift Zone vents and flow field Lava flows from the June 27 breakout pose no immediate threat to residential areas. Near-vent areas could erupt or collapse without warning with spatter and/or ash being wafted within the gas plume. In addition, potentially-lethal concentrations of sulfur dioxide gas may be present within 1 km downwind of vent areas. Active lava flows within forested areas can produce methane blasts capable of propelling rocks and other debris into the air. All recently active lava flows are within Hawaiʻi Volcanoes National Park and adjacent State land managed by the Department of Land and Natural Resources or the Office of Hawaiian Affairs.

Kīlauea Crater Ash and Pele's hair can be carried several kilometers downwind, and potentially-lethal concentrations of sulfur dioxide can be present within 1 km downwind.

Viewing Summary:
East Rift Zone flow field Most of the flow field is within the closed-access Kahaualeʻa Natural Area Reserve (NAR) or the Wao Kele o Puna Forest Reserve (DLNR, OHA) and can only be viewed from the air. Under favorable weather conditions at night, distant glow from the active flows can be seen from the County Viewing Area at Kalapana (Lava hotline 961-8093) and from the end of the Chain of Craters Road and a few other areas within Hawaiʻi Volcanoes National Park.

Puʻu ʻŌʻō Cone and Kīlauea Crater These areas are within Hawaiʻi Volcanoes National Park; Park access and viewing information can be found at http://www.nps.gov/havo/planyourvisit/lava2.htm.

Definitions of Terms Used:

ash: tephra less than 2 mm (5/64 inches) in size.

CD: Hawai`i County Civil Defense

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.

DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a geophysical event of uncertain volcanic 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 (weak DI events) to 2-3 days (strong DI events) 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/Peace Day vents.

glow: light from an unseen source; indirect light.

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 which is, in turn, 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 160 m (525 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at a depth of 200 m (660 ft) below the Halema`uma`u Crater floor. From November, 2009, to now, a lava pond surface has been visible in this pit.

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).

LPs: - Long Period (LP) events refer to earthquakes that have a lower frequency or tone than typical earthquakes and are usually attributed to the resonance of fluid- and gas-filled conduits, cracks and/or chambers. Because of their association with fluids and gases, LP earthquakes in the vicinity of volcanoes can be useful for monitoring purposes. At other volcanoes LP earthquakes are also known as low-frequency earthquakes, tornillos or B-type earthquakes.

mauka, makai: Hawaiian terms for directions relative to the coast - makai or ma kai (toward the coast) and mauka or ma uka (toward the highlands or away from the coast).

microradian: a measure of angle equivalent to 0.000057 degrees.

pali: Hawaiian term for cliff or precipice.

rise/fall events: one of the episodic behaviors exhibited by the summit lava lake starting in 2009. An event starts with a rise in lava level, a decrease in high-frequency summit tremor amplitude, a decrease or total stoppage of spattering, and a small decrease in tilt. After a period of minutes to hours, the lava will abruptly drain back to its previous level amidst resumed vigorous spattering, seismic tremor amplitude will increase for a short time (a seismic tremor burst) before resuming background levels, and summit tilt will return to its previous level. Gas emissions decrease significantly during the high lava stand (the plume gets wispy), and resume during its draining phase. Taken together, the geophysical characteristics suggest that, during the high lava stand, lava is puffed up with gas trapped under the lava lake crust.

seismic tremor dropout: these behaviors are identical to rise/fall events except that the lava lake level doesn't rise or fall significantly. High-frequency seismic tremor, gas emissions, and spattering decrease abruptly during a dropout. A dropout can end with a burst of seismic tremor and a significant pulse of gas emissions.

tephra: all material deposited by fallout from an eruption-related plume, regardless of size.

tonne (t): metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 0.984 English tons.

More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.

Additional Information:
For a definition of volcano alert levels and aviation color codes: http://volcanoes.usgs.gov/activity/alertsystem/index.php

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://hvo.wr.usgs.gov/seismic/volcweb/earthquakes/

HVO Contact Information: askHVO@usgs.gov

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



HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Sunday, August 17, 2014 9:23 AM HST (Sunday, August 17, 2014 19:23 UTC)


This report on the status of Kilauea volcanic activity, in addition to maps, photos, and Webcam images (available at http://hvo.wr.usgs.gov/activity/kilaueastatus.php), was prepared by the USGS Hawaiian Volcano Observatory (HVO). All times are Hawai`i Standard Time.

KILAUEA VOLCANO (VNUM #332010)
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: Kīlauea continued to erupt at its summit and within the East Rift Zone, and gas emissions remained elevated. At the summit, there was minor net inflation over the past day with slight fluctuations in lava level. At the middle East Rift Zone, the front of the June 27th flow was 9.0 km east-northeast of the vent.

Recent Summit Observations: Kīlauea's summit experienced several minor fluctuations in tilt over the past day, with overall minor net inflation. The lava lake level also fluctuated slightly, in large part due to spattering and outgassing, and was roughly 35-40 m below the Overlook crater rim. Seismic tremor was low, but it varied with changes in spattering on the surface of the lava lake. There was no major change in seismic activity on Kīlauea over the past day. GPS receivers spanning the summit caldera recorded about 5 cm of extension between early May and early July. Since then there has been no net extension or contraction. During the week ending on August 12, 2014, the elevated summit sulfur-dioxide emission rate was measured at 5,100 tonnes/day (see caveat below), and a tiny amount of particulate material was carried aloft by the plume.

Recent East Rift Zone Observations: There was slight inflation at Puʻu ʻŌʻō during the last 24 hours. Glow was visible overnight above outgassing pits on the northeast, south, and southeast edges of Puʻu ʻŌʻō's crater floor. The June 27th flow continued to advance into forest east-northeast of Puʻu ʻŌʻō. The tube-fed flow slowed and widened over the past several days, and its distal tip was 9.0 km from the vent (straight-line distance) as located by a satellite image on August 15. The flow also hosted a broad area of breakouts mid-way along its length, at around 34 km from the vent. The most recent sulfur-dioxide emission-rate measurement was 600 tonnes per day (from all East Rift Zone sources) on July 31, 2014.



Sulfur Dioxide Emission Rate estimation caveat: Starting in 2014, we report the emission rate estimated by a new, more accurate method. The numbers increase by a factor of 2-4 but the actual emission rate has not changed. For more on this reporting change, please read http://hvo.wr.usgs.gov/volcanowatch/view.php?id=207

Background:
Summit The summit lava lake is within an elliptical crater (unofficially called the Overlook crater), which has dimensions of approximately 160 m (520 ft) by 210 m (690 ft), inset within the eastern portion of Halemaʻumaʻu Crater. The lake level has varied from about 25 m to more than 200 m (out of sight) below the floor of Halemaʻumaʻu Crater. The Overlook crater has been more-or-less continuously active since it opened during a small explosive event on March 19, 2008. The lake level responds to summit tilt changes with the lake generally receding during deflation and rising during inflation. During 2013 and early 2014, the lava level has been typically between 30 m (100 ft) and 60 m (200 ft) below the floor of Halemaʻumaʻu Crater. Small collapses in the Overlook crater are common, and over time have resulted in a gradual enlargement of the Overlook crater. The ambient SO2 concentrations near the vent vary greatly, but are persistently higher than 10 ppm and frequently exceed 50 ppm (upper limit of detector) during moderate trade winds. The gas plume typically includes a small amount of ash-sized tephra (mostly fresh spatter bits and Pele's hair from the circulating lava lake). The heaviest pieces are deposited onto nearby surfaces while the finer bits can be carried several kilometers before dropping out of the plume.

East Rift Zone vents and flow field The eruption in Kīlauea's middle East Rift Zone started with a fissure eruption on January 3, 1983, and continued with few interruptions at Puʻu ʻŌʻō Cone, or temporarily from vents within a few kilometers to the east or west. A fissure eruption on the upper east flank of Puʻu ʻŌʻō Cone on Sept. 21, 2011, drained the lava lakes and fed a lava flow (Peace Day flow) that advanced southeast through the abandoned Royal Gardens subdivision to the ocean within Hawaiʻi Volcanoes National Park in early December 2011. The flows stalled and re-entered the ocean starting on November 24, 2012, until activity started to decline and the ocean entry ceased in August 20, 2013; the flow was dead by early November, 2013. The Kahaualeʻa flow, which started from the spatter cone/lava lake at the northeast edge of the Puʻu ʻŌʻō crater floor in mid-January 2013 was dead by late April, but a new flow (informally called Kahaualeʻa 2) became active in the same area in early May 2013, waxing with inflation and waning with deflation. The Kahaualeʻa 2 flow died following the onset of a new breakout from the northeast flank of Puʻu ʻŌʻō on June 27, 2014.

Hazard Summary:
East Rift Zone vents and flow field Lava flows from the June 27 breakout pose no immediate threat to residential areas. Near-vent areas could erupt or collapse without warning with spatter and/or ash being wafted within the gas plume. In addition, potentially-lethal concentrations of sulfur dioxide gas may be present within 1 km downwind of vent areas. Active lava flows within forested areas can produce methane blasts capable of propelling rocks and other debris into the air. All recently active lava flows are within Hawaiʻi Volcanoes National Park and adjacent State land managed by the Department of Land and Natural Resources or the Office of Hawaiian Affairs.

Kīlauea Crater Ash and Pele's hair can be carried several kilometers downwind, and potentially-lethal concentrations of sulfur dioxide can be present within 1 km downwind.

Viewing Summary:
East Rift Zone flow field Most of the flow field is within the closed-access Kahaualeʻa Natural Area Reserve (NAR) or the Wao Kele o Puna Forest Reserve (DLNR, OHA) and can only be viewed from the air. Under favorable weather conditions at night, distant glow from the active flows can be seen from the County Viewing Area at Kalapana (Lava hotline 961-8093) and from the end of the Chain of Craters Road and a few other areas within Hawaiʻi Volcanoes National Park.

Puʻu ʻŌʻō Cone and Kīlauea Crater These areas are within Hawaiʻi Volcanoes National Park; Park access and viewing information can be found at http://www.nps.gov/havo/planyourvisit/lava2.htm.

Definitions of Terms Used:

ash: tephra less than 2 mm (5/64 inches) in size.

CD: Hawai`i County Civil Defense

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.

DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a geophysical event of uncertain volcanic 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 (weak DI events) to 2-3 days (strong DI events) 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/Peace Day vents.

glow: light from an unseen source; indirect light.

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 which is, in turn, 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 160 m (525 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at a depth of 200 m (660 ft) below the Halema`uma`u Crater floor. From November, 2009, to now, a lava pond surface has been visible in this pit.

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).

LPs: - Long Period (LP) events refer to earthquakes that have a lower frequency or tone than typical earthquakes and are usually attributed to the resonance of fluid- and gas-filled conduits, cracks and/or chambers. Because of their association with fluids and gases, LP earthquakes in the vicinity of volcanoes can be useful for monitoring purposes. At other volcanoes LP earthquakes are also known as low-frequency earthquakes, tornillos or B-type earthquakes.

mauka, makai: Hawaiian terms for directions relative to the coast - makai or ma kai (toward the coast) and mauka or ma uka (toward the highlands or away from the coast).

microradian: a measure of angle equivalent to 0.000057 degrees.

pali: Hawaiian term for cliff or precipice.

rise/fall events: one of the episodic behaviors exhibited by the summit lava lake starting in 2009. An event starts with a rise in lava level, a decrease in high-frequency summit tremor amplitude, a decrease or total stoppage of spattering, and a small decrease in tilt. After a period of minutes to hours, the lava will abruptly drain back to its previous level amidst resumed vigorous spattering, seismic tremor amplitude will increase for a short time (a seismic tremor burst) before resuming background levels, and summit tilt will return to its previous level. Gas emissions decrease significantly during the high lava stand (the plume gets wispy), and resume during its draining phase. Taken together, the geophysical characteristics suggest that, during the high lava stand, lava is puffed up with gas trapped under the lava lake crust.

seismic tremor dropout: these behaviors are identical to rise/fall events except that the lava lake level doesn't rise or fall significantly. High-frequency seismic tremor, gas emissions, and spattering decrease abruptly during a dropout. A dropout can end with a burst of seismic tremor and a significant pulse of gas emissions.

tephra: all material deposited by fallout from an eruption-related plume, regardless of size.

tonne (t): metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 0.984 English tons.

More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.

Additional Information:
For a definition of volcano alert levels and aviation color codes: http://volcanoes.usgs.gov/activity/alertsystem/index.php

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://hvo.wr.usgs.gov/seismic/volcweb/earthquakes/

HVO Contact Information: askHVO@usgs.gov

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



HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Saturday, August 16, 2014 9:21 AM HST (Saturday, August 16, 2014 19:21 UTC)


This report on the status of Kilauea volcanic activity, in addition to maps, photos, and Webcam images (available at http://hvo.wr.usgs.gov/activity/kilaueastatus.php), was prepared by the USGS Hawaiian Volcano Observatory (HVO). All times are Hawai`i Standard Time.

KILAUEA VOLCANO (VNUM #332010)
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: Kīlauea continued to erupt at its summit and within the East Rift Zone, and gas emissions remained elevated. At the summit, there was gradual inflation and the lava lake level rose slightly. At the middle East Rift Zone, the front of the June 27th flow was 8.7 km east-northeast of the vent.

Recent Summit Observations: Kīlauea's summit continued gradual inflation over the past day. The inflation was tracked by the lava lake level, which rose to roughly 35 m below the Overlook crater rim. Seismic tremor was low, but it varied with changes in spattering on the surface of the lava lake. There was no major change in seismic activity on Kīlauea over the past day. GPS receivers spanning the summit caldera recorded about 5 cm of extension between early May and early July. Since then there has been no net extension or contraction. During the week ending on August 12, 2014, the elevated summit sulfur-dioxide emission rate was measured at 5,100 tonnes/day (see caveat below), and a tiny amount of particulate material was carried aloft by the plume.

Recent East Rift Zone Observations: There was only slight apparent inflation at Puʻu ʻŌʻō during the last 24 hours, but some of this may be due to rainfall. Glow was visible overnight above outgassing pits on the northeast, south, and southeast edges of Puʻu ʻŌʻō's crater floor. The June 27th flow continued to advance into forest east-northeast of Puʻu ʻŌʻō. The tube-fed flow slowed and widened over the past few days, and its distal tip was 8.7 km from the vent (straight-line distance) when mapped on August 14. The flow also hosted a broad area of breakouts mid-way along its length, at around 34 km from the vent. The most recent sulfur-dioxide emission-rate measurement was 600 tonnes per day (from all East Rift Zone sources) on July 31, 2014.



Sulfur Dioxide Emission Rate estimation caveat: Starting in 2014, we report the emission rate estimated by a new, more accurate method. The numbers increase by a factor of 2-4 but the actual emission rate has not changed. For more on this reporting change, please read http://hvo.wr.usgs.gov/volcanowatch/view.php?id=207

Background:
Summit The summit lava lake is within an elliptical crater (unofficially called the Overlook crater), which has dimensions of approximately 160 m (520 ft) by 210 m (690 ft), inset within the eastern portion of Halemaʻumaʻu Crater. The lake level has varied from about 25 m to more than 200 m (out of sight) below the floor of Halemaʻumaʻu Crater. The Overlook crater has been more-or-less continuously active since it opened during a small explosive event on March 19, 2008. The lake level responds to summit tilt changes with the lake generally receding during deflation and rising during inflation. During 2013 and early 2014, the lava level has been typically between 30 m (100 ft) and 60 m (200 ft) below the floor of Halemaʻumaʻu Crater. Small collapses in the Overlook crater are common, and over time have resulted in a gradual enlargement of the Overlook crater. The ambient SO2 concentrations near the vent vary greatly, but are persistently higher than 10 ppm and frequently exceed 50 ppm (upper limit of detector) during moderate trade winds. The gas plume typically includes a small amount of ash-sized tephra (mostly fresh spatter bits and Pele's hair from the circulating lava lake). The heaviest pieces are deposited onto nearby surfaces while the finer bits can be carried several kilometers before dropping out of the plume.

East Rift Zone vents and flow field The eruption in Kīlauea's middle East Rift Zone started with a fissure eruption on January 3, 1983, and continued with few interruptions at Puʻu ʻŌʻō Cone, or temporarily from vents within a few kilometers to the east or west. A fissure eruption on the upper east flank of Puʻu ʻŌʻō Cone on Sept. 21, 2011, drained the lava lakes and fed a lava flow (Peace Day flow) that advanced southeast through the abandoned Royal Gardens subdivision to the ocean within Hawaiʻi Volcanoes National Park in early December 2011. The flows stalled and re-entered the ocean starting on November 24, 2012, until activity started to decline and the ocean entry ceased in August 20, 2013; the flow was dead by early November, 2013. The Kahaualeʻa flow, which started from the spatter cone/lava lake at the northeast edge of the Puʻu ʻŌʻō crater floor in mid-January 2013 was dead by late April, but a new flow (informally called Kahaualeʻa 2) became active in the same area in early May 2013, waxing with inflation and waning with deflation. The Kahaualeʻa 2 flow died following the onset of a new breakout from the northeast flank of Puʻu ʻŌʻō on June 27, 2014.

Hazard Summary:
East Rift Zone vents and flow field Lava flows from the June 27 breakout pose no immediate threat to residential areas. Near-vent areas could erupt or collapse without warning with spatter and/or ash being wafted within the gas plume. In addition, potentially-lethal concentrations of sulfur dioxide gas may be present within 1 km downwind of vent areas. Active lava flows within forested areas can produce methane blasts capable of propelling rocks and other debris into the air. All recently active lava flows are within Hawaiʻi Volcanoes National Park and adjacent State land managed by the Department of Land and Natural Resources or the Office of Hawaiian Affairs.

Kīlauea Crater Ash and Pele's hair can be carried several kilometers downwind, and potentially-lethal concentrations of sulfur dioxide can be present within 1 km downwind.

Viewing Summary:
East Rift Zone flow field Most of the flow field is within the closed-access Kahaualeʻa Natural Area Reserve (NAR) or the Wao Kele o Puna Forest Reserve (DLNR, OHA) and can only be viewed from the air. Under favorable weather conditions at night, distant glow from the active flows can be seen from the County Viewing Area at Kalapana (Lava hotline 961-8093) and from the end of the Chain of Craters Road and a few other areas within Hawaiʻi Volcanoes National Park.

Puʻu ʻŌʻō Cone and Kīlauea Crater These areas are within Hawaiʻi Volcanoes National Park; Park access and viewing information can be found at http://www.nps.gov/havo/planyourvisit/lava2.htm.

Definitions of Terms Used:

ash: tephra less than 2 mm (5/64 inches) in size.

CD: Hawai`i County Civil Defense

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.

DI tilt event: DI is an abbreviation for 'deflation-inflation' and describes a geophysical event of uncertain volcanic 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 (weak DI events) to 2-3 days (strong DI events) 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/Peace Day vents.

glow: light from an unseen source; indirect light.

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 which is, in turn, 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 160 m (525 ft) in diameter at the Halema`uma`u Crater floor, is about 50 m in diameter at a depth of 200 m (660 ft) below the Halema`uma`u Crater floor. From November, 2009, to now, a lava pond surface has been visible in this pit.

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).

LPs: - Long Period (LP) events refer to earthquakes that have a lower frequency or tone than typical earthquakes and are usually attributed to the resonance of fluid- and gas-filled conduits, cracks and/or chambers. Because of their association with fluids and gases, LP earthquakes in the vicinity of volcanoes can be useful for monitoring purposes. At other volcanoes LP earthquakes are also known as low-frequency earthquakes, tornillos or B-type earthquakes.

mauka, makai: Hawaiian terms for directions relative to the coast - makai or ma kai (toward the coast) and mauka or ma uka (toward the highlands or away from the coast).

microradian: a measure of angle equivalent to 0.000057 degrees.

pali: Hawaiian term for cliff or precipice.

rise/fall events: one of the episodic behaviors exhibited by the summit lava lake starting in 2009. An event starts with a rise in lava level, a decrease in high-frequency summit tremor amplitude, a decrease or total stoppage of spattering, and a small decrease in tilt. After a period of minutes to hours, the lava will abruptly drain back to its previous level amidst resumed vigorous spattering, seismic tremor amplitude will increase for a short time (a seismic tremor burst) before resuming background levels, and summit tilt will return to its previous level. Gas emissions decrease significantly during the high lava stand (the plume gets wispy), and resume during its draining phase. Taken together, the geophysical characteristics suggest that, during the high lava stand, lava is puffed up with gas trapped under the lava lake crust.

seismic tremor dropout: these behaviors are identical to rise/fall events except that the lava lake level doesn't rise or fall significantly. High-frequency seismic tremor, gas emissions, and spattering decrease abruptly during a dropout. A dropout can end with a burst of seismic tremor and a significant pulse of gas emissions.

tephra: all material deposited by fallout from an eruption-related plume, regardless of size.

tonne (t): metric unit equal to 1,000 kilograms, 2,204.6 lbs, or 0.984 English tons.

More definitions with photos can be found at http://volcanoes.usgs.gov/images/pglossary/index.php.

Additional Information:
For a definition of volcano alert levels and aviation color codes: http://volcanoes.usgs.gov/activity/alertsystem/index.php

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://hvo.wr.usgs.gov/seismic/volcweb/earthquakes/

HVO Contact Information: askHVO@usgs.gov

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



Update Archive

Older updates can be found using the HVO Alert Archive Search.

New Update Format

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