USGS Volcano Hazards Program Volcano Update


HVO update page and observatory web site


Activity Summary: A second DI deflation started at midnight while the lava lake level fluctuated. Seismic activity increased in the upper east rift zone. At Pu`u `O`o, short lava flows issued from the NE pit and south sources; the lava lake in the NE pit remained active with spattering visible from the sources along the north and south crater floor edges. Lava flows southeast of Pu`u `O`o continued to be weakly active on the coastal plain. Seismic tremor levels were low, and gas emissions were elevated.

Recent Observations at Kilauea summit: Back-to-back DI events have halted the slow upward rise of the lava lake. DI inflation started around 5 am yesterday and was followed by a second DI deflation at midnight last night. Changes in the lava lake level due to the DI events were masked by the continuing rise/fall events. The inner ledge continued to be submerged during the rise part of rise/fall events and it showed evidence of slumping at least its shallowest layers into the lava lake yesterday changing the shape of the ledge edge.

The most recent (preliminary) sulfur dioxide emission rate measurement was 700 tonnes/day on October 22, 2012; measurements will resume with the return of moderate trade winds. Although not measured today, a small amount of ash-sized tephra (mostly fresh spatter bits and Pele's hair, but also bits of the vent wall) was probably carried out of the vent in the gas plume and deposited on nearby surfaces. Cracking noises, sometimes audible from the Jaggar overlook and caused by rocks of the vent wall fracturing from the heat, emanate sporadically from the vent.

The GPS network continued recording extension across the summit caldera at the rate of about 1 cm/wk since the beginning of October. Seismic tremor levels remained generally low (variable during rise/fall events) and upper east rift zone seismicity continued to increase. Forty-five earthquakes were strong enough to be located beneath Kilauea: 5 west and south of the summit caldera, 32 within the upper east rift zone (centered beneath Puhimau Crater), 2 in the vicinity of the middle east rift zone, and 6 on south flank faults.

Background: The summit lava lake is deep within an ~160 m (520 ft) diameter cylindrical vent with nearly vertical sides inset within the east wall and floor of Halema`uma`u Crater. Its level fluctuates from about 40 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. Most recently, the surface level of the lava lake has remained below an inner ledge (~50 m or 165 ft below the floor of Halema`uma`u Crater on October 9, 2012), sometimes rising to flood the ledge. The lake level responds to summit tilt changes with the lake receding during deflation and rising during inflation.

Recent Observations at the middle east rift zone vents: Surface flows continued weak activity within the abandoned Royal Gardens subdivision, with flows extending seaward across the coastal plain. These flows have not advanced much over the past week, and are about 1.4 km (0.9 miles) from the coast based on position estimates from webcams. Minor flow activity also continued on the pali.

At Pu`u `O`o, activity remained elevated. A short lava flow issued from one of the sources on the south edge of the crater floor just after noon yesterday and two short flows issued from both the northeast pit and the same south source between 1 and 3 am this morning. The perched lava lake within the northeastern pit remained active and spattering was recorded from sources at the south and north edges of the crater floor.

The tiltmeter on the north flank of Pu`u `O`o cone recorded probable DI events at delays that were getting progressively shorter with time: Friday's summit DI deflation was recorded at 4 am yesterday (17 hour delay), DI inflation was recorded at noon (7 hour delay), and the current DI deflation was recorded at 2 am this morning (2 hour delay). GPS receivers spanning the Pu`u `O`o crater continued to record extension rates of about 0.5 cm/wk since the beginning of October. Seismic tremor levels near Pu`u `O`o increased slightly. The most recent (preliminary) sulfur dioxide emission rate measurement was 200 tonnes/day on October 22, 2012, from all east rift zone sources.

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 that advanced southeast through the abandoned Royal Gardens subdivision to the ocean within Hawai`i Volcanoes National Park in early December. Since late December, the flows have remained intermittently active on the pali and the coastal plain but have not entered the ocean. 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. All recently active lava flows are within Hawai`i Volcanoes National Park, adjacent State land managed by the Department of Land and Natural Resources, and private property within the Royal Gardens subdivision; the lava flows do not pose a 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 - The new breakout lava flows were within the closed-access Kahauale'a Natural Area Reserve (NAR) and the abandoned Royal Gardens subdivision and can only be viewed from the air. Under favorable weather conditions, glow from these flows may be reflected in clouds which can be seen from the County Viewing Area at Kalapana (Lava hotline 961-8093). Pu`u `O`o Cone, the strip of coastal plain nearest the ocean, and Kilauea Crater - these areas are within Hawai`i Volcanoes National Park; Park access and viewing information can be found at http://www.nps.gov/havo/planyourvisit/lava2.htm.

Update in Common Alerting Protocol (CAP) format