USGS Volcano Hazards Program Volcano Update

HVO update page and observatory web site

Activity Summary: The current eruption of Kilauea volcano started 31 years ago today and it continued at two locations with little change in the past 24 hours. The summit tiltmeter network recorded minor fluctuations, and the lava-lake level dropped slightly. At the middle east rift zone, the Pu`u `O`o vent continued to feed the Kahauale`a 2 lava flow, which was active as small scattered breakouts burning forest to the northeast. Gas emissions remained elevated.

Recent Observations at Kilauea summit: The summit tiltmeters recorded minor fluctuations. The lava-lake level dropped slightly to a measured 47 m (154 ft) below the floor of Halema`uma`u. Gas emissions continued to be elevated: during the week of 12/24-12/31, the summit SO2 emission rate varied between 2,100 and 3,000 tonnes/day (see caveat below). A small amount of ash-sized tephra (mostly fresh spatter bits and Pele's hair from the spattering sinks) was carried out of the vent with the gas plume and deposited onto nearby surfaces.

Seismic tremor levels were low and variable with no dropouts. Eighteen earthquakes were strong enough to be located beneath Kilauea Volcano in the past 24 hours: 3 in the Ka`oiki Pali area, 4 within the southwest rift zone, 5 south of Halema`uma`u Crater, 2 within the upper east rift zone, 1 within the middle east rift zone, and 3 on south flank faults. GPS receivers spanning the summit caldera recorded line length changes that mimicked the short-term trends in tilt (mostly DI tilt events) over the past month; the long-term, cross-caldera measurements indicate continued extension at a rate averaging 10 cm/yr (4 in/yr) since March, 2010.

Background: The summit lava lake is within a nearly-cylindrical vent cavity with a diameter of ~160 m (520 ft) and nearly vertical sides inset within the east wall and floor of Halema`uma`u Crater. Its level has varied from about 25 m to more than 200 m (out of sight) below the floor of Halema`uma`u Crater. The vent has been mostly active since opening with a small explosive event on March 19, 2008. The surface level of the lava lake has remained mostly below the inner ledge (~31 m or 100 ft below the floor of Halema`uma`u Crater on October 29, 2012) and has risen above and flooded the ledge in October 2012 and January 2013 before receding to greater depths. The lake level responds to summit tilt changes with the lake generally receding during deflation and rising during inflation.

Recent Observations at the middle east rift zone vents: The Pu`u `O`o vent continued to inflate slowly. The tiltmeter at Pu`u `O`o cone recorded minor fluctuations over weak inflationary tilt. The most recent sulfur-dioxide emission-rate measurement was 250 tonnes per day on December 24, 2013, from all east rift zone sources; emission rates typically ranged between 150 and 450 t/d since July 2012. GPS receivers on the north rim and south flank of Pu`u `O`o cone recorded minor fluctuations over weak extension (about 1 cm over the past 3 months and 25 cm since April 2010).

The Pu`u `O`o eruption continued without much change. Spatter cones on the floor of Pu`u `O`o crater displayed persistent bright glow; the southeast spatter cone erupted 4 more short flows between 6 am and 6 pm yesterday although we can only see the north side of the cone and can't see any flows going southward within the crater. The northeast spatter cone continued to feed the Kahauale`a 2 lava flow, which extends 6.3 km (3.9 mi) northeast of Pu`u `O`o (per 12/26 mapping). When weather permits, distant views of the flow front from the PNcam and R3cam (working intermittently) showed small breakouts and burning forest in several spots.

Background: The eruption in Kilauea's middle east rift zone started with a fissure eruption on January 3, 1983, and continued with few interruptions at Pu`u `O`o Cone, or temporarily from vents within a few kilometers to the east or west. A fissure eruption on the upper east flank of Pu`u `O`o 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 Hawai`i 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 Kahauale`a flow, which started from the spatter cone/lava lake at the northeast edge of the Pu`u `O`o crater floor in mid-January, 2013, was dead by late April, but a new flow (informally called Kahauale`a 2) became active in the same general area in early May. In general, activity waxes with inflation and wanes with deflation.

Hazard Summary: East rift vents and flow field - near-vent areas could erupt or collapse without warning with spatter and/or ash being wafted within the gas plume; potentially-lethal concentrations of sulfur dioxide gas may be present within 1 km downwind of vent areas. Active lava flows within forest can produce methane blasts that propel rocks and other debris into the air. All recently active lava flows are within Hawai`i Volcanoes National Park and adjacent State land managed by the Department of Land and Natural Resources or the Office of Hawaiian Affairs; the lava flows do not pose an imminent hazard to any structures not already within the County-declared mandatory evacuation zone. Kilauea Crater - ash and Pele's hair can be carried several kilometers downwind; 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 Kahauale'a 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 within Hawai`i Volcanoes National Park. Pu`u `O`o Cone and Kilauea Crater - these areas are within Hawai`i Volcanoes National Park; Park access and viewing information can be found at

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 ot 2-4 but the actual emission rate has not changed. For more on this reporting change, please read

Update in Common Alerting Protocol (CAP) format