Here in Hawaii nei, we don’t have the dramatically changing leaf colors and brisk temperatures that mark the arrival of fall. And as October arrived this year, our night skies were dark, with no warm orange glow indicative of lava erupting on the surface.
Kilauea’s most recent eruption stopped on September 16. This was the briefest of the five eruptions that have occurred at the summit of Kilauea since 2020. The eruption lasted about six days and, like the four eruptions before it, filled in a portion of the summit that collapsed in 2018.
Though Kilauea is one of Earth’s most active volcanoes, periods of time with no eruptive activity on the surface are not uncommon. Since 2020, there have been periods lasting weeks to several months between eruptions and during which there is no active lava on the surface.
Prior to the recent summit eruptions, Kilauea didn’t erupt for over two years following the large lower East Rift Zone eruption in 2018. Looking back at Kilauea’s eruptive history over the past couple hundred years, periods of weeks to months or even sometimes years between eruptions are relatively common. The longest period without any Kilauea eruptions over the past 200 years was abnormally long and lasted 18 years!
For USGS Hawaiian Volcano Observatory (HVO) staff, these non-eruptive periods offer a bit of respite from the flurry of activity that comes with responding to increased unrest or a new eruption. However, because our volcanoes erupt so frequently, these quiet periods also come with a bit of unease. HVO staff ask themselves questions such as: How long will it be until a volcano erupts again? Where and when will the next eruption take place?
HVO’s monitoring network helps us to evaluate the answers to these questions. The monitoring network continuously tracks activity beneath the surface despite the surface itself appearing still. Right now, recent ground deformation south of Kilauea summit is beginning to slow, but an increased number of earthquakes are being detected in this region due to a seismic swarm. The rift zones of Kilauea along with other active volcanoes in Hawaii, including Mauna Loa, remain quiet. We expect to see changes to these monitoring parameters when any of Hawaii’s active volcanoes begin to show signs of unrest.
Though Hawaii’s volcanoes currently aren’t erupting, other volcanoes around the world remain active. Here in the United States, Great Sitkin and Shishaldin are erupting in Alaska, generating lava flows and ash plumes in the remote Aleutian Islands. Multiple volcanoes are active in the Democratic Republic of the Congo, Ecuador, Indonesia, Japan, the Philippines and Russia. Individual volcanoes are also active in Chile, Ethiopia, Italy, Mexico and Papua New Guinea. Elsewhere in the world, volcanoes can also cause unease even when not erupting. In Italy, there is increased earthquake activity at Campi Flegrei, a caldera that includes part of the city of Naples. The dense population of people living in the vicinity of this volcanic center has garnered much attention and the situation is complicated by evacuations during previous periods of unrest there which did not escalate to eruption.
Eruptions in Hawaii over the past five years have fortunately offered safe viewing, have not required evacuations, and have only minimally impacted infrastructure. However, communities living on the flanks of Hawaii’s active volcanoes should always be prepared for the range of activities that Hawaii’s volcanoes can exhibit. You and your family can be better prepared for one of the many natural hazards that can impact Hawaii Island residents by taking some time now, when it is quiet, to visit the Hawaii County Civil Defense website on preparedness: https://www.hawaiicounty.gov/departments/civil-defense/emergency-preparedness. Though the skies above Hawaii’s volcanoes are dark right now, they will certainly be lit up by the glow of eruptions in the future.
Volcano
activity updates
Kilauea is not erupting. Its USGS Volcano Alert level is ADVISORY.
The area just south of Kilauea’s summit is currently showing signs of elevated unrest. Rates of inflationary tilt increased two days ago in the area south of the Kilauea summit caldera and is now leveling off. A seismic swarm in the Kilauea summit region started on Oct. 5, with over 150 earthquakes in 24 hours. Most of the earthquakes are occurring in a region south of the caldera at depths of around 2.5–3.5 km (1.5–2 mi) below the surface. The most recent sulfur dioxide (SO2) emission rate, of approximately 150 tonnes per day, was measured on Sept. 25.
Mauna Loa is not erupting. Its USGS Volcano Alert Level is at NORMAL.
Webcams show no signs of activity on Mauna Loa. Seismicity remains low. Summit ground deformation rates indicate slow inflation as magma replenishes the reservoir system following the recent eruption. SO2 emission rates are at background levels.
One earthquake was reported felt in the Hawaiian islands during the past week: a M3.3 earthquake 1 km (0.6 mi) SW of Pahala at 32 km (20 mi) depth on Oct. 4 at 12:11 a.m. HST. HVO continues to closely monitor Kilauea and Mauna Loa.
Please visit HVO’s website for past Volcano Watch articles, Kilauea and Mauna Loa updates, volcano photos, maps, recent earthquake information, and more. Email questions to askHVO@usgs.gov.
Volcano Watch is a weekly article and activity update written by U.S. Geological Survey Hawaiian Volcano Observatory scientists and affiliates.
