Subject: HVO Status Report 20180731_1017
HAWAIIAN VOLCANO OBSERVATORY STATUS REPORT
U.S. Geological Survey
Tuesday, July 31, 2018, 10:17 AM HST (Tuesday, July 31, 2018, 20:17 UTC)
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
Fissure 8 continues to erupt lava into the channel leading northeastward from the vent. No overflows were reported this morning and lava levels in the more distant portions of the channel system appear low. At the coast, the south edge of the lava flow has not advanced westward in the past day, and remains less than 175 m (0.1 mi) from the Pohoiki boat ramp in Isaac Hale Park. Lava along the south edge of the flow was oozing more to the east but there were a few ooze-outs to the west that were distant from the coast and not directly threatening Pohoiki. Lava is actively entering the ocean along a broad 2 km (1.2 mi) flow front centered near the former Ahalanui Beach Park with a more minor entry building a pointed delta near the south edge of the flow.
No other fissures are active this morning.
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 activity 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 significant changes in temperature, crack width, or gas emissions have been noted for several days.
Volcanic gas emissions remain very high. VOG information can be found at https://vog.ivhhn.org/
The ocean entry is a hazardous area. The interaction of lava with the ocean creates “laze”, a corrosive seawater plume laden with hydrochloric acid and fine volcanic particles that drifts downwind and can irritate the skin, eyes, and lungs. Close to the ocean entry, flying debris from explosive interaction between lava and water is a primary hazard. Additionally, submarine magma-water interaction can result in explosive activity beyond the visible lava delta, creating a hazard that extends offshore. The lava delta is unstable because it is built up to 800 m (0.5 mi) from the former coastline 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.
Magma continues to be supplied to the Lower East Rift Zone. Seismicity remains relatively low although 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 at any time. Residents downslope of the region of fissures should remain informed and heed all Hawaii County Civil Defense messages and warnings.
Kīlauea Volcano Summit
A magnitude-4.5 earthquake occurred beneath the south caldera at 12:30 AM. Seismicity at Kilauea’s summit decreased after the collapse event at 7:59 AM HST July 31 which was very similar to previous events. Inward slumping of the rim and walls of Halemaʻumaʻu continues.
Sulfur dioxide emissions from the volcano’s summit are very low. This gas and minor amounts of ash resuspended by wind are being transported downwind. Small bursts of ash and gas may coincide with the summit collapse events. The summit region is occasionally impacted by sulfur dioxide from the lower East Rift Zone eruption.
Forecasts of ashfall under forecast wind conditions: https://volcanoes.usgs.gov/observatories/hvo/ash_information.html
Subscribe to these messages: https://volcanoes.usgs.gov/vns2/
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:
Summary of volcanic hazards from Kīlauea eruptions:
Recent Earthquakes in Hawai’i (map and list):
Explanation of Volcano Alert Levels and Aviation Color Codes:
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.