Alert Level: NORMAL, Color Code: GREEN 2023-12-07 19:24:18 UTC
HAWAIIAN VOLCANO OBSERVATORY MONTHLY UPDATE
U.S. Geological Survey
Thursday, December 7, 2023, 9:24 AM HST (Thursday, December 7, 2023, 19:24 UTC)
MAUNA LOA (VNUM #332020)
19°28'30" N 155°36'29" W, Summit Elevation 13681 ft (4170 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN
Shallow seismicity beneath Mauna Loa's summit and upper-elevation flanks has been stable over the past month; approximately 80 small-magnitude earthquakes (below M3.0) were detected, which is on par with previous months. Starting in July 2023, there had been an elevated rate of earthquakes deeper than 8 mi (13 km) beneath and southwest of Mauna Loa's summit caldera, then this area saw a deep earthquake swarm in late October and early November. Since then, however, the rate of deep earthquakes has returned to background levels.
Data from Global Positioning System (GPS) instruments on Mauna Loa indicate inflation as magma replenishes the summit reservoir system.
Gas and temperature data from a station on Mauna Loa's Southwest Rift Zone show no significant changes in the past month.
HVO continues to closely monitor Mauna Loa and will issue another update in one month, or earlier should conditions change significantly.
Background: Mauna Loa is the largest active volcano on our planet and covers half of the Island of Hawaiʻi. Eruptions tend to produce voluminous, fast-moving lava flows that can impact communities on the east and west sides of the Island.
Mauna Loa eruptions typically start at the summit and, within minutes to months of eruption onset, can migrate into either the Northeast or Southwest Rift Zone, or radial vents on the north flank. Since its first well-documented eruption in 1843, the volcano has erupted 34 times with intervals between eruptions ranging from months to decades. Mauna Loa erupted most recently in 2022.
More Information:
This notice contains volcanoes not displayed here: Hualalai (NORMAL/GREEN), Haleakala (NORMAL/GREEN), Mauna Kea (NORMAL/GREEN), Kama'ehuakanaloa (UNASSIGNED/UNASSIGNED).
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 Hawaiʻi and American Samoa.
CONTACT INFORMATION:
askHVO@usgs.gov
Subscribe to these messages: https://volcanoes.usgs.gov/vns2/
Summary of volcanic hazards from eruptions: https://www.usgs.gov/observatories/hvo/hazards
Recent earthquakes in Hawaiʻi (map and list): https://www.usgs.gov/observatories/hvo
Explanation of Volcano Alert Levels and Aviation Color Codes: https://www.usgs.gov/programs/VHP/volcanic-alert-levels-characterize-conditions-us-volcanoes
