Kilauea Daily Update issued Mar 20, 2008 06:49 HST Volcano Alert Level WATCH - Aviation Color Code ORANGE
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
Thursday, March 20, 2008 06:49 HST (Thursday, March 20, 2008 16:49 UTC)
KILAUEA VOLCANO (CAVW#1302-01-)
19.43°N 155.29°W, Summit Elevation 4009 ft (1222 m)
Volcano Alert Level: WATCH
Aviation Color Code: ORANGE
This report, in addition to maps, photos, and webcam images (available using the menu bar above), was prepared by the Hawaiian Volcano Observatory (HVO):
Activity Summary for last 24 hours: Lava continued to flow into the ocean at the Waikupanaha and Ki ocean entries. The east margin of the flow field continued to advance slowly eastward into the adjacent kipuka and was about 150 m (500 ft) east of the County viewing area yesterday morning. No new explosions have occurred at Kilauea summit. Sulfur dioxide emission rates and seismic tremor levels continued elevated to several times background levels at Kilauea summit.
Hazard Summary: Hazardous conditions exist in four areas on Kilauea volcano - potentially harmful sulfur dioxide concentrations and possible small explosions at the summit, potentially harmful sulfur dioxide concentrations and unstable conditions around the Pu`u `O`o/July 21/TEB vent area, lava flow threat to the Royal Gardens subdivision and the coastal plain to the southeast, and hazardous conditions associated with lava entering the ocean.
1. The current increase in sulfur dioxide emission rates at the summit means that SO2 concentrations in the air are likely to be at hazardous levels for areas downwind of emission sources in Halema`uma`u crater. The National Park Service has closed Crater Rim Drive through the south caldera area until further notice (http://www.nps.gov/havo/closed_areas.htm). Most people are sensitive to sulfur dioxide at these levels. Children and individuals with asthma, chronic obstructive pulmonary disease (COPD), or other breathing problems especially should avoid downwind areas. During tradewind conditions (brisk winds from the northeast), concentrations will be highest and most hazardous in the south caldera: southwest rift zone, south caldera pullouts, and the Halema`uma`u overlook parking lot - The National Park Service has closed this section of Crater Rim Drive. During weak or southerly winds, concentrations may be high and hazardous throughout the summit area of Hawai`i Volcanoes National Park and nearby communities. Stay informed about SO2 concentrations in continuously monitored areas at Jaggar Museum and Kilauea Visitor Center (http:// www.nature.nps.gov/air/webcams/parks/havoso2alert/havoalert.cfm).
There is a possibility of small explosions from Halema`uma`u Crater.
2. Vent areas and lava channels are hazardous and conditions can change rapidly. Sulfur dioxide emissions from Pu`u `O`o are high and result in hazardous concentrations downwind. Access to the 7/21 eruption site in the Kahauale`a Natural Area Reserve is closed (see http://www.state.hi.us/dlnr/chair/pio/HtmlNR/07-N076.htm). Wao Kele o Puna is also closed.
3. There continues to be a threat from lava flows to anyone within Royal Gardens subdivision and the coastal plain. As long as lava flows are active south of fissure D, the subdivision is within likely flow paths of future flows. The rootless shields, which are now less than two miles from the subdivision, can collapse and release lava flows that advance that distance within a few days. Tube- or channel-fed lava flows established within the subdivision and on the coastal plain remain a threat due to tube ruptures which can produce new lava flows. Lava flows advancing through vegetation are hazardous and can produce fire and methane explosions that propel chunks of lava and rock several feet into the air. Hawai`i County Civil Defense has been notified and is taking appropriate measures (www.lavainfo.us).
4. Lava entering the ocean poses two additional hazards - potential collapse and laze. Lava entering the ocean builds a delta over its own rubble that is extremely unstable. That delta can collapse without warning and expose very hot surfaces to waves which can explode and throw rock debris up to one-quarter mile inland. For these reason, spectators should avoid the delta and the area one-quarter mile inland. The interaction between seawater and lava produces a steam plume laced with acids and fine particles of volcanic glass or ‘laze’ that is unhealthy if inhaled and can produce skin or eye irritation if contacted. Hawai`i County continues to prepare for safe public viewing hopefully this weekend. For details, see www.lavainfo.us.
TEB lava flows at the coast as of yesterday evening (from combined HVO and NPS eruption crew reports): Lava continued to flow into the ocean at the Waikupanaha and Ki ocean entries; evening visitors could see nearly a dozen entry points on the Waikupanaha delta but only incandescence in steam from the Ki entry. The eastern margin of active lava flows was still about 150 m (500 ft) west of the County viewing area yesterday morning and creeping eastward and over the old sea cliff onto the 1990 lava delta. Flows edging through the kipuka continued to produce local fires.
Last 24 hours of the TEB vent area: There was no incandescence from the TEB, rootless shields, or the Kalalua flow visible in the webcam overnight. Seismic tremor levels were at low levels.
Last 24 hours at Pu`u `O`o: Diffuse incandescence was observed by webcam overnight in the crater. The tiltmeter again recorded weak deflation from a source to the souteast. GPS receivers on opposite sides of the crater continued to record contraction at a rate averaging 2 cm/month over the past 3 months. Seismic tremor levels were at low values. The SO2 emission rate was about 2,050 tonnes/day on March 19.
Last 24 hours at Kilauea summit: Seismic tremor levels have been elevated above their already-elevated levels since the explosion at 2:58 HST March 19. The tremor levels abruptly decreased beginning at 2:30 am only at the seismometer nearest the Halema`uma`u gas vent. At about the same time, incandescence diminished from the the gas vent as viewed in the new webcam. The summit tiltmeter network recorded continued weak deflation. Only one small earthquake was located beneath Kilauea caldera and two were located on south flank faults.
Sulfur dioxide (SO2) emission rates from the summit area have been elevated at several times background values since early January and have more than doubled since March 12. The most recent emission rate measurement was about 1,600 tonnes/day on Mar. 19, compared to a background rate of between 150-200 tonnes/day.
Sulfur dioxide concentrations were again below detection limits at Jaggar museum and Kilauea Visitors Center. Trade (northeasterly) winds kept gas emissions in the south caldera where SO2 concentrations were up to 40 ppm in areas downwind of Halema`uma`u crater along Crater Rim Drive (mostly between Halema`uma`u parking lot and the southwest rift zone pullout during trade winds) and up to 140 ppm near the Halema`uma`u overlook close to the new vent.
