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Hawaiian Volcano Observatory Status Report, USGS, Wednesday, June 27, 2018 - Notícia OVGA 02-07-2018

 

KILAUEA VOLCANO (VNUM #332010)
19°25'16" N 155°17'13" W, Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WARNING
Current Aviation Color Code: ORANGE

Kīlauea Volcano Lower East Rift Zone

The eruption in the lower East Rift Zone (LERZ) continues with no significant change during the past 24 hours.

Fountains from Fissure 8 spatter cone continue to supply lava to the open channel with only small, short-lived overflows. Small overflows on both sides of the upslope portion of the channel occurred shortly after midnight, June 27. None of these overflows extended past the existing flow field. The spatter cone is now 180 ft tall at its highest point, and fountains only occasionally rise above that point. Lava is entering the sea this morning on the southern side of the entry area primarily through the open channel, but also along a 1-kilometer (0.6 mi) wide area. The morning overflight revealed that the northern margin of the flow field at the coast is oozing fresh lava at several points in the area of Kapoho Beach Lots.

Pele's hair and other lightweight volcanic glass fragments from the lava fountain at Fissure 8 continue to fall downwind of the fissure, dusting the ground within a few hundred meters (yards) of the vent. High winds may waft lighter particles to greater distances. Residents are urged to minimize exposure to these volcanic particles, which can cause skin and eye irritation similar to volcanic ash.

The most recent map of lava flows can be found at https://volcanoes.usgs.gov/volcanoes/kilauea/multimedia_maps.html

HVO field crews are on site tracking the fountains, lava flows, and spattering from Fissure 8 as conditions allow and are reporting information to Hawaii County Civil Defense. Observations are also collected on a daily basis from cracks in the area of Highway 130; no changes in temperature, crack width, or gas emissions have been noted for several days.

Volcanic gas emissions remain very high from Fissure 8 eruptions. Continuing trade wind conditions are expected to bring VOG to the southern and western parts of the Island of Hawaii. VOG information can be found at https://vog.ivhhn.org/

The ocean entry is a hazardous area. Venturing too close to an ocean entry on land or the ocean exposes you to flying debris from sudden explosive interaction between lava and water. Also, the lava delta is unstable because it is built on unconsolidated lava fragments and sand. This loose material can easily be eroded away by surf, causing the new land to become unsupported and slide into the sea. Additionally, the interaction of lava with the ocean creates "laze", a corrosive seawater plume laden with hydrochloric acid and fine volcanic particles that can irritate the skin, eyes, and lungs.

Magma continues to be supplied to the Lower East Rift Zone. Seismicity remains relatively low in the area with numerous small magnitude earthquakes and low amplitude background tremor. Higher amplitude tremor is occasionally being recorded on seismic stations close to the ocean entry.

Additional ground cracking and outbreaks of lava in the area of the active fissures are possible. Residents downslope of the region of fissures should heed all Hawaii County Civil Defense messages and warnings.

Kīlauea Volcano Summit

At 10:41 PM HST on June 26, after approximately 25 hours of elevated seismicity, a collapse explosion occurred at the summit producing an ash-poor steam plume that rose less than 1,000 ft above the ground surface (< 5000 ft above sea level) before drifting to the SW. The energy released by the event was equivalent to a magnitude 5.4 earthquake. Seismicity dropped abruptly from a high of 25-35 earthquakes per hour (many in the magnitude 2-3 range) prior to the collapse explosion down to 10 or fewer earthquakes per hour afterwards. Within 4 hours seismicity began to creep up again averaging about 25 earthquakes per hour by daybreak (June 27). Inward slumping of the rim and walls of Halemaʻumaʻu continues in response to ongoing subsidence at the summit. 

Sulfur dioxide emissions from the volcano's summit have dropped to levels that are about half those measured prior to the onset of the current episode of eruptive activity. This gas and minor amounts of ash are being transported downwind, with small bursts of ash and gas accompanying intermittent explosive activity.

For forecasts of where ash would fall under forecast wind conditions, please consult the Ash3D model output here:

https://volcanoes.usgs.gov/observatories/hvo/ash_information.html

Information on volcanic ash hazards and how to prepare for ash fall maybe found at http://www.ivhhn.org/information#ash (health impacts) OR https://volcanoes.usgs.gov/volcanic_ash/ (other impacts). 

MORE INFORMATION

Subscribe to these messages: https://volcanoes.usgs.gov/vns2/
Webcam images: https://volcanoes.usgs.gov/volcanoes/kilauea/multimedia_webcams.html
Photos/Video: https://volcanoes.usgs.gov/volcanoes/kilauea/multimedia_chronology.html
Lava Flow Maps: https://volcanoes.usgs.gov/volcanoes/kilauea/multimedia_maps.html
Definitions of terms used in update: https://volcanoes.usgs.gov/volcanoes/kilauea/extra/definitions.pdf
Overview of Kīlauea summit (Halemaʻumaʻu) and East Rift Zone (Puʻu ʻŌʻō) eruptions:
https://volcanoes.usgs.gov/volcanoes/kilauea/extra/background.pdf

Summary of volcanic hazards from Kīlauea eruptions:
https://volcanoes.usgs.gov/volcanoes/kilauea/extra/hazards.pdf
Recent Earthquakes in Hawai'i (map and list):
https://volcanoes.usgs.gov/hvo/earthquakes/
Explanation of Volcano Alert Levels and Aviation Color Codes:
https://volcanoes.usgs.gov/activity/alertsystem/index.php
https://pubs.usgs.gov/fs/2006/3139/ 

CONTACT INFORMATION:

[email protected] 

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. 

 

 

Fonte: USGS