USGS Volcano Hazards Program Volcano Update


HVO update page and observatory web site


Activity Summary: Kilauea continued to erupt at two locations: At the summit, stable conditions and minor fluctuations of the lava lake continued. In the east rift zone, lava flowed onto the Pu`u `O`o crater floor early this morning and probably remained active northeast of the cone on older flows to the north of Pu`u Kahauale`a. To the southeast of Pu`u `O`o, lava was entering the ocean in multiple areas both inside and outside the National Park boundary. Gas emissions remained elevated.

Recent Observations at Kilauea summit: The lava lake continued to circulate and its level fluctuated but remained just below the inner ledge. The summit tiltmeter network recorded no tilt change - neither inflation nor deflation. The most recent (preliminary) sulfur dioxide emission rate measurement was 700 tonnes/day on February 15, 2013; this value is within the range of typical background emission rates between rise/fall events. A very small amount of ash-sized tephra (mostly fresh spatter bits and Pele's hair) was carried out of the vent in the gas plume and deposited on nearby surfaces.

Seismic tremor levels were low - spattering continued from multiple, migrating sinks around the lake rim. Five earthquakes were strong enough to be located beneath Kilauea Volcano in the past 24 hours: 2 in the Ka`oiki Pali area, 1 beneath Pu`u `O`o in the middle east rift zone, and 2 on south flank faults. Over the past month, the GPS receivers located on either side of the summit caldera have recorded about 1.5 cm of extension - slightly higher than the average rate of 0.9 cm/mo over the past 3 years of summit extension.

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 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. 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: Peace Day lava activity on the pali and the coastal plain fed by lava tubes extending from Pu`u `O`o, continued in three areas with no significant changes according to our Webcams. Lava flows probably remained active just above the pali about 5 km (3 mi) southeast from Pu`u `O`o. On the coastal plain, an approximately 1 km-wide (0.6 mi wide) lava flow remained active with minor surface activity straddling the easternmost boundary of Hawai`i Volcanoes National Park at the coast and entering the ocean at two or more locations, inside and outside Hawai`i Volcanoes National Park. To the west, a 350 m (1,150 ft) wide lava flow continued to advance slowly toward the coast with scattered breakouts through this morning (visible in Mobile Cam 2).

HAZARD ALERT: Lava entering the ocean builds lava deltas. The lava delta and adjacent areas are some of the most hazardous areas on the flow field. Frequent delta/bench collapses give little warning, can produce explosions capable of throwing both dense and molten rocks hundreds of meters (yards) in all directions (inland as well as out to sea), and can produce damaging local waves. The steam plume produced by lava entering the ocean contains fine lava fragments and an assortment of acid droplets that can be harmful to your health. The rapidly changing conditions near the ocean entry have been responsible for many injuries and a few deaths.

Within the Pu`u `O`o crater, the southwestern spatter cone continued to issue a small amount of lava; at about 1 am, there was a large amount of lava issued from the south side of the northeast spatter cone that was largely out of direct view of our Webcam array; this early morning breakout also resulted in new breakouts on the Kahauale`a tube high on the northeast flank of Pu`u `O`o cone. The tiltmeter on the north flank of Pu`u `O`o cone recorded fluctuations with an abrupt 1.3 microradian drop accompanying the above-mentioned crater-floor activity. Seismic tremor levels near Pu`u `O`o remained low. The most recent (preliminary) sulfur dioxide emission rate measurement was 300 tonnes/day on February 12, 2013, from all east rift zone sources.

Outside the crater and across the northeast flank of Pu`u `O`o cone, multiple lava flow lobes, informally called the Kahauale`a flow, continued to be active northeast on older Pu`u `O`o flows north of Pu`u Kahauale`a to the base of the 2007 perched channel (visible in Pu`u `O`o East Thermal and North Webcams); it's too early to tell whether the early morning activity from the NE spatter cone, the source of the Kahauale`a flow, will affect the Kahauale`a flow progress.

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. Since late December 2011, the flows have remained intermittently active on the pali and the coastal plain and finally re-entered the ocean starting on November 24, 2012. 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; the lava flows do not pose a hazard to any structures not already within the County-declared mandatory evacuation zone. Lava deltas, which can collapse into the ocean without warning, are extremely hazardous and should be avoided (see HAZARD ALERT above). 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) and the abandoned Royal Gardens subdivision and can only be viewed from the air. A small part of the western flow field near the coast in within Hawai`i Volcanoes National Park (see below for access info). Under favorable weather conditions, active flows-when present-can be seen from the County Viewing Area at Kalapana (Lava hotline 961-8093). 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 http://www.nps.gov/havo/planyourvisit/lava2.htm.

Update in Common Alerting Protocol (CAP) format