ALASKA VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Thursday, March 5, 2026, 12:19 PM AKST (Thursday, March 5, 2026, 21:19 UTC)
Lava continues to erupt slowly within the summit crater of Great Sitkin Volcano. Seismic activity remains very low, with only a few small rockfalls detected over the past day. Satellite and webcam views were obscured by clouds.
The current lava eruption began in July 2021 and, since then, has filled most of the summit crater and advanced into valleys below. There have been no explosions at Great Sitkin Volcano since an event in May 2021. The volcano is monitored using local seismic and infrasound sensors, satellite data, webcams, and regional infrasound and lightning networks.
To view monitoring data and other information about Great Sitkin: https://avo.alaska.edu/volcano/great-sitkin
Unrest continues at Shishaldin Volcano. Seismic activity remains elevated, with numerous small earthquakes and intermittent episodes of volcanic tremor detected beneath the volcano. Minor steaming from the summit vent was observed in web camera images over the past day. No unusual activity was observed in satellite data.
Local seismic and infrasound sensors, web cameras, and a geodetic network are used to monitor Shishaldin Volcano. In addition to the local monitoring network, AVO uses nearby geophysical networks, regional infrasound and lightning data, and satellite images to detect eruptions.
To view monitoring data and other information about Shishaldin: https://avo.alaska.edu/volcano/shishaldin
Matt Haney, Scientist-in-Charge, USGS mhaney@usgs.gov (907) 786-7497
David Fee, Coordinating Scientist, UAFGI dfee1@alaska.edu (907) 378-5460
Contact AVO: https://avo.alaska.edu/contact
The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.
HAWAIIAN VOLCANO OBSERVATORY MONTHLY UPDATE
U.S. Geological Survey
Thursday, March 5, 2026, 10:05 AM HST (Thursday, March 5, 2026, 20:05 UTC)
No significant activity was detected at Ofu-Olosega volcano during the past month. The USGS National Earthquake Information Center reported no earthquakes of magnitude 2.5 or greater in the vicinity of the volcano. Two small unlocatable earthquakes were detected on Manuʻa Islands seismic network stations the evening and night of February 12 to 13 (local time). There were no reports of local residents feeling these earthquakes.
Background: The islands of Ofu and Olosega in the Manuʻa Islands of eastern American Samoa, with a combined length of 6 kilometers (3.7 miles), are separated by a narrow strait. The islands are formed by two eroded, coalescing basaltic shield volcanoes whose slopes dip to the east and west. The Nuʻutele tuff cone, forming a small crescent-shaped island immediately off the west end of Ofu, is of Holocene age (less than 11,650 years). A submarine eruption occurred in 1866, 3 kilometers (1.9 miles) southeast of Olosega, along the Samoan Ridge between Olosega and Taʻu Island. From: https://volcano.si.edu/volcano.cfm?vn=244010.
More Information: https://www.usgs.gov/volcanoes/ofu-olosega
No significant activity was detected at Taʻū volcano during the past month. The USGS National Earthquake Information Center reported no earthquakes of magnitude 2.5 or greater in the vicinity of the volcano. Two small unlocatable earthquakes were detected on Manuʻa Islands seismic network stations the evening and night of February 12 to 13 (local time). There were no reports of local residents feeling these earthquakes. A Global Positioning System (GPS) instrument on Taʻū Island recorded no significant deformation.
The FAGA broadband seismometer located on eastern Taʻū Island is currently out of service. The TAU broadband seismometer on western Taʻū Island remains operational.
Background: In the Manuʻa Islands of eastern American Samoa, Taʻū Island is the top of a shield volcano, most of which is beneath the ocean. The volcano has a summit caldera, though landslides have removed the southern part of the caldera. Two rift zones are present on Taʻū, one to the northeast and one to the northwest. The northwest rift zone aligns with the Samoan Ridge, a predominantly submarine feature that leads to the islands of Ofu and Olosega. This ridge was formed by volcanic activity associated with the Samoa hotspot, which is currently located at the Vailulu‘u seamount 40 kilometers (25 miles) east of Ta‘ū Island. A submarine eruption occurred in 1866 on the Samoan Ridge between Ta‘ū and Ofu-Olosega.
More Information: https://www.usgs.gov/volcanoes/ta-u-island
No significant activity was detected at Tutuila volcano during the past month. The USGS National Earthquake Information Center reported no earthquakes of magnitude 2.5 or greater in the vicinity of the volcano.
Background: Tutuila Island is an elongated and eroded group of five Pliocene-to-Pleistocene-aged volcanoes constructed along two or three rifts trending south-southwest to north-northeast. The Leone Volcanics, in the southernmost part of the island, represent the youngest eruption deposits. Eruptions occurred during the Holocene (less than 11,650 years ago) along a 5-kilometer (3-mile) north-to-south trending fissure, forming a group of initially submarine tuff cones and subsequent subaerial cinder cones that produced fresh-looking pāhoehoe lava flows. An ash layer overlying a cultural deposit in the southwestern part of the island was radiocarbon dated at 440 ± 200 CE (Addison et al., 2006). From: https://volcano.si.edu/volcano.cfm?vn=244020.
More Information: https://www.usgs.gov/volcanoes/tutuila-island
Additional Resources
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.
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
HAWAIIAN VOLCANO OBSERVATORY MONTHLY UPDATE
U.S. Geological Survey
Thursday, March 5, 2026, 9:40 AM HST (Thursday, March 5, 2026, 19:40 UTC)
Mauna Loa seismic activity was similar to the previous month, with a tight clustering of events under Mokuʻāweoweo and a weaker concentration of events in the south caldera region (a continuation of elevated earthquake production from the previous month). A total of 116 earthquakes were detected beneath Mauna Loa's summit region in the February reporting period, while the prior month had 123 earthquakes. Data from Global Positioning System (GPS) instruments on Mauna Loa show variable rates of inflation at the summit over the past six months. This is associated with refilling of the summit reservoir system following the 2022 eruption.
Gas and temperature data from a station on Mauna Loa's Southwest Rift Zone indicate these values are at background levels, with little change relative to previous months.
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 northwest 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:
No significant activity was detected at Hualālai volcano during the past month. Seismic activity remained low, and was representative of background activity levels at the volcano. The continuously recording Global Positioning System (GPS) instrument on Hualālai recorded no significant deformation in the past month.
Background: Hualālai is the third most active volcano on the Island of Hawaiʻi and typically erupts two to three times per 1,000 years. It last erupted in 1801 and, more recently, had a damaging seismic swarm in 1929 that was probably the result of a shallow intrusion of magma. The volcano is monitored by a continuous GPS instrument and seismometer located southeast of the summit, as well as several instruments on the nearby flanks of Mauna Loa and Mauna Kea volcanoes. Key sites on Hualālai and western Mauna Loa are resurveyed using GPS receivers every few years to detect any changes in the volcano's shape.
More Information:
Hualālai volcano summary also available by phone: (808) 967-8877
Hualālai website: https://www.usgs.gov/volcanoes/hualalai
No significant activity was detected at Haleakalā volcano during the past month. HVO seismometers recorded no earthquakes in the vicinity of the volcano. The continuously recording Global Positioning System (GPS) instrument on Haleakalā recorded no significant deformation in the past month.
Background: The most recent eruption on Haleakalā was probably between A.D. 1480 and 1600. The volcano is monitored by a continuous GPS instrument and seismometer located near the southwest edge of the summit crater. Key sites on Haleakalā are resurveyed using GPS receivers every few years to detect any changes in the volcano's shape.
More Information:
Haleakalā volcano summary also available by phone: (808) 967-8877
Haleakalā website: https://www.usgs.gov/volcanoes/haleakala
No significant activity was detected at Mauna Kea volcano during the past month. Seismic activity remained low, and was representative of background activity levels at the volcano; all earthquakes were of small magnitudes.
Background: Mauna Kea is a shield volcano in the post-shield stage; it last erupted about 4,600 years ago. Monitoring is conducted by one GPS instrument and three seismometers on the volcano, plus instruments on adjacent Kohala volcano and denser geodetic and seismic networks on the north flank of Mauna Loa volcano to the south. With a summit at 4,207 meters (13,803 feet) above sea level, Mauna Kea is the tallest mountain in the State of Hawaii, and it is the tallest mountain on Earth when measured from its base on the ocean floor.
More Information:
Mauna Kea volcano summary also available by phone: (808) 967-8877
Mauna Kea website: https://www.usgs.gov/volcanoes/mauna-kea
No significant activity was detected at Kamaʻehuakanaloa (formerly Lōʻihi Seamount) during the past month. Seismic activity remained low, and was representative of background activity levels at the volcano; all earthquakes were of small magnitudes.
Background: Intermittent earthquake activity has been recorded in the vicinity of Kamaʻehuakanaloa (formerly Lōʻihi Seamount) since as early as 1952. The most energetic earthquake sequence occurred in July–August 1996, which included more than 4,000 earthquakes, with nearly 300 events larger than M3.0 and 95 events in the M4.0 to 4.9 range. More recently, a swarm of 100 earthquakes occurred on May 11, 2020, with 18 events in the M3.0 to 3.9 range. There are no working monitoring instruments on Kamaʻehuakanaloa, whose peak is about 1,000 meters (3,280 feet) below sea level. All real-time information about the volcano is derived from land-based seismometers on the Island of Hawai‘i.
More Information:
Kamaʻehuakanaloa website: https://www.usgs.gov/volcanoes/kama'ehuakanaloa
Hawaiian Volcanoes at Elevated Alert Levels:
Kīlauea Volcano (YELLOW/ADVISORY) updates: https://www.usgs.gov/volcanoes/kilauea/volcano-updates
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.
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
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE
U.S. Geological Survey
Thursday, March 5, 2026, 8:45 AM HST (Thursday, March 5, 2026, 18:45 UTC)
Activity Summary:
The Halemaʻumaʻu eruption of Kīlauea is paused. Episode 42 ended February 15 at 11:38 p.m. HST. Inflation continued over the last 24 hours and the modeled forecast window for the onset of episode 43 lava fountaining is now March 10-15.
No significant activity has been noted along Kīlauea’s East Rift Zone or Southwest Rift Zone.
A recap of episode 42 can be found in this Status Report.
Significant changes in activity between Daily Updates are posted here: https://www.usgs.gov/observatories/hvo/observatory-messages
Summit Observations:
Continuous glow at the south vent and more intermittent glow at the north vent were visible in webcams overnight. This morning, both vents remain quiet and emitting steady gas plumes. Continuous low level seismic tremor was observed over the last 24 hours.
The summit has continued to inflate over the last 24 hours. As of this morning, the UWD tiltmeter has recorded 25.3 microradians of inflationary tilt since the end of episode 42, with about 3.1 microradians of net inflation over the past 24 hours.
Sulfur dioxide (SO2) emission rates from the summit have typically averaged 1000-1500 t/d during eruptive pauses. Webcams show the plume blowing southwest this morning in moderate trade winds.
Rift Zone Observations:
Rates of seismicity and ground deformation remain very low in the East Rift Zone and Southwest Rift Zone. SO2 emissions from the East Rift Zone remain below the detection limit.
Analysis:
The initial rapid rebound of tilt and glow from both vents indicate that another fountaining episode is likely. The overall inflationary trend has been interrupted by periods of no inflation or slight deflation recorded across all four summit tiltmeters that may impact the onset of episode 43 fountaining. Periods of weak deflation or no inflation have not been common in the early stages of repose between fountaining episodes. These changes in tilt rate are not predictable and create uncertainty in modeling the onset of episode 43 fountaining. Models suggest the forecast window for the start of episode 43 fountaining is likely between March 10 and March 15. The forecast window may change if inflation is interrupted by additional periods of deflation.
Kīlauea has been erupting episodically since December 23, 2024, primarily from two vents (north and south) in Halema‘uma‘u. Eruptive episodes, which generally last for less than 12 hours, are separated by pauses that can be as long as over two weeks.
HVO continues to closely monitor Kīlauea and is in contact with Hawai‘i Volcanoes National Park and the Hawai‘i County Civil Defense Agency about eruptive hazards.
Please see the Hawaiʻi Volcanoes National Park website for visitor information: https://www.nps.gov/havo/index.htm
Recap of episode 41:
A recap of episode 42 can be found in this Status Report.
Resources:
The following links provide more information about the current eruption that began on December 23, 2024:
Hazards:
This episodic eruption is occurring within a closed area of Hawai'i Volcanoes National Park.
Other significant hazards exist around Kīlauea caldera from Halemaʻumaʻu crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes. Close to the vents, the tephra material on the crater rim is prone to cracking, slumping, and small landslides that sometimes expose hot and molten material within. This underscores the extremely hazardous nature of Kīlauea's caldera rim surrounding Halemaʻumaʻu crater, an area that has been closed to the public since late 2007.
More Information:
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.
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
NORTHERN MARIANA ISLANDS WEEKLY UPDATE
U.S. Geological Survey
Friday, March 6, 2026, 9:47 AM ChST (Thursday, March 5, 2026, 23:47 UTC)
Report prepared by the U.S. Geological Survey.
NORTHERN MARIANAS VOLCANOES
No definitive signs of unrest were detected at any other Northern Mariana Island volcanoes during the past week.
Monitoring of Northern Mariana Islands Volcanoes
Northern Mariana Island volcanoes are monitored using seismo-acoustic sensors on Saipan, and by examining satellite imagery. We also use distant seismic stations in Guam and Chichijima, Japan, and hydroacoustic data from Wake Island, when available.
This level of monitoring can detect significant volcanic activity in the CNMI but cannot provide advanced warning of eruptions.
Due to a lack of geophysical monitoring on any of the volcanic islands, the following volcanoes have alert levels of UNASSIGNED: Anatahan, Sarigan, Farallon de Pajaros, Supply Reef, Maug, Asuncion, Agrigan, Pagan, Almagan, and Guguan.
For definitions of Aviation Color Codes and Volcano Alert Levels: https://www.usgs.gov/programs/VHP/volcanic-alert-levels-characterize-conditions-us-volcanoes
SUBSCRIBE TO VOLCANO ALERT MESSAGES by email: http://volcanoes.usgs.gov/vns/
CNMI Homeland Security and Emergency Management
https://opd.gov.mp/library/agency/homeland-security-and-emergency-management.html
USGS Northern Mariana Duty Scientist (907) 786-7497
http://volcano.wr.usgs.gov/cnmistatus.php
Satellite information, Washington VAAC
http://www.ssd.noaa.gov/VAAC/washington.html