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Frequently Asked Questions about Kīlauea's Summit Eruptions

Kīlauea's Recent Summit Eruptions - Frequently Asked Questions

Color photograph of erupting vents
This view of the eruption site within Kīlauea caldera was captured in the afternoon of Tuesday, September 12 from the southeast rim of Kaluapele. Multiple vents are spattering and effusing lava as the Kīlauea summit eruption nears the end of its second full day. USGS photo by M. Zoeller. 

What is happening at the summit of Kīlauea?

Kīlauea volcano has been intermittently erupting. This is an exciting time on Kīlauea because several eruptions have occurred at the summit following the 2018 summit collapse. Five eruptions have occurred since 2020. For up-to-date information on  Kīlauea, see the daily eruption update

For information about the Kīlauea summit eruptions in 2020-2023, see this webpage: December 2020 - June 2023 Summit Eruptions | U.S. Geological Survey (


How long will an eruption last?

Eruptions at Kīlauea summit over the past several years have lasted from about two weeks to over a year. Typically, these eruptions start vigorously and decrease in vigor over time (as this eruption has done). 


Will the crater and/or caldera fill up and overflow with all this lava?

Color map of eruption
A new eruption at the summit of Kīlauea volcano began at approximately 3:13 p.m. on Sunday, September 10, 2023. This map depicts activity within Halema‘uma‘u on the second day of the eruption, September 11. Lava is currently erupting from multiple fissures on the eastern down-dropped block from the 2018 caldera collapse, inundating both the block itself and sections of the western crater floor. The western floor was built during the previous four eruptions in Halema‘uma‘u, dating back to 2020; the extent of lava from the June 2023 eruption is marked in light purple. Approximately 448 acres (181 hectares) have been covered with new lava in the past two days.

In 2018, the southern portion of Kīlauea's summit caldera partially collapsed. Portions of the caldera floor lowered by as much as 500 m (1,600 ft). Eruptions at Kīlauea's summit since 2020 have slowly been filling in the deepest parts that collapsed, which were in Halema‘uma‘u crater. During the September 2023 eruption, the eastern rim of the crater has been buried by new lava flows. Pāhoehoe lava flows cover most of the crater floor except high ground formed during previous eruptive activity in the southwest portions of the crater. The volume of the 2018 collapse was approximately 0.8 cubic km (0.2 cubic miles); eruptions at Kīlauea's summit since 2020 have filled only about 25% of the volume of the 2018 collapse and so there is still much volume to fill before lava approaches the upper caldera floor above the downdropped block (and even more volume to fill before lava approaches the caldera rim, which is even higher). 


How deep is the crater? How deep is the caldera?

The difference in elevation between Halema‘uma‘u crater/the downdropped block and the upper caldera floor is still over 100 meters (330 ft). The rim of the caldera is another 150 meters (500 ft) above that. The September 11, 2023—Kīlauea summit eruption reference map shows the current geometry of Kīlauea summit.


Are there any official names for features in the caldera or how does USGS refer to them?

Color photograph of eruption in caldera
An aerial view of the eruption at the summit of Kīlauea at approximately 12:20 p.m. H.S.T. on September 12, 2023. Multiple minor fountains remain active on the downdropped block (right) within Kīlauea's summit caldera. USGS photo by N. Deligne. 

The official name of Kīlauea caldera is Kaluapele and Halemaʻumaʻu is an officially named feature within the caldera. There are a number of other officially-named features in the summit region, which are listed in the U.S. Board on Geographic Names database ( In the eruption area, the Hawaiian Volcano Observatory has been unofficially referring to the large block that lowered in 2018 as the “downdropped” or “down-dropped” block. During eruptions, Hawaiian Volcano Observatory staff often informally name vents—by letter, number, or some other description—to track their activity. For example, fissure 8 of the lower East Rift Zone eruption in 2018 was the eighth fissure to being erupting. Since then, the cone that formed at fissure 8 has been officially renamed “Ahuʻailāʻau.” Vents active during recent eruptions at Kīlauea summit eruption have not typically been informally named because the activity is so dynamic initially. 


In the dark is the livestream camera using some kind of filter to see the lava (red filter, infrared, etc.), or is this just natural light from the lava?

The camera isn’t designed for super hot materials and there is a filter that is supposed to cut out the near infrared light. However, there is likely some near infrared bleeding into the image, making the colors look the way they do during eruptions. View the livestream here:


How can I view an eruption?

Eruptions at the summit of Kīlauea occur within Hawai’i Volcanoes National Park.  

The National Park published guidelines on “How to Safely View the New Eruption in Hawaiʻi Volcanoes National Park.” Please visit the Hawai’i Volcanoes National Park website for the most up-to-date information on viewing eruptions within the National Park: 

Alternatively, view the Kīlauea summit livestream camera and other Kīlauea summit webcams


Why are some areas within Hawai‘i Volcanoes National Park closed to the public? 

Color photograph of eruption and plume
Photo shows volcanic gases from the current eruption at Kīlauea’s summit being transported southwest into the closed area (left side of photo). This photo also shows the cracks, cliffs, and uneven ground surfaces present in the closed area of Hawai‘i Volcanoes National Park. USGS photo by K. Mulliken on 12/21/2020. (Public domain.)

Some areas within the Park are closed because of ongoing, persistent volcanic hazards that can cause serious injury or death. These hazards can include:   

  • Sulfur dioxide and other volcanic gases: Trade winds transport gases predominantly to the southwest and conditions can change rapidly. As a result, portions of the closed area within Hawai‘i Volcanoes National Park have consistently poor air quality. USGS Hawaiian Volcano Observatory (HVO) staff carry gas-detection devices, gas masks [respirators] and eye protection so that they are aware of air quality conditions at all times and are able to respond to worsening conditions.   
  • Possible explosions or ejection of hot lava: Conditions at a lava lake can be unpredictable. As the 2008-2018 lava lake demonstrated, sudden rockfall into the lava lake, for example, could potentially generate an explosion with the ejection of hot lava. HVO field crews wear high-visibility flame-resistant clothing, gloves, eye protection, and hard hats while working near the rim and maintain contact with scientists monitoring data feeds so they are alerted to sudden changes.  
  • Cracks, cliffs, and uneven ground surface: The 2018 Kīlauea summit collapse dramatically altered the landscape within the closed area, particularly near the caldera rim and Halema‘uma‘u, the location of the current eruption. Since 2018, HVO staff have studied and mapped the area and are aware of the location of unstable surfaces, hazards, and the safest areas from which to observe the current eruption. HVO field crews entering the area are equipped with Global Positioning System (GPS) units to ensure they are accessing safe locations along safe routes and are using consistent routes so as not to damage or disturb NPS resources (native plants and nēnē, for example). 

Many of these areas have been closed since 2008, when volcanic activity resulted in the creation of a lava lake (2008-2018). 


What steps do HVO and NPS staff take to be safe in hazardous areas? 

Hawaiian Volcano Observatory scientists continue to make observations and measurements of the ongoing Kīlauea summit eruption wi
Photo shows USGS HVO field crew member working in the closed area and wearing appropriate protective gear. While in the field, USGS HVO field crews maintain constant communication with HVO staff monitoring data for changes, and with the National Park Service. Constant, multi-way communications between HVO field crews, HVO monitoring staff, and NPS officials allow all parties to communicate and be aware of the volcano’s status and changes. USGS photo by M. Patrick. (Public domain.)

Kīlauea’s summit is dynamic and the situation can rapidly change, as the several recent eruptions demonstrate. In addition to personal protective equipment such as gas detectors, respirators, eye protection, hard hat, high visibility heat-resistant clothing, gloves, and boots, HVO field crews are in constant communication with HVO scientists watching geophysical monitoring data. If monitoring data indicate changes that could result in unstable conditions, field crews are immediately informed and can rapidly evacuate the area. HVO field crews carry InReach tracking devices, so their field positions are known at all times. HVO field crews carry radios and maintain contact with National Park Service Rangers. 

Basic safety/PPE gear that HVO staff wear/carry: heat-resistant clothing, sturdy boots, helmet, high-VIS USGS identifier, eye protection, GPS (with waypoints, tracks), phone for communication, gas mask (respirator), gas-detection device, gloves, rain gear, first aid kit, radio for communication with NPS, InReach tracking device.


Why is it necessary for USGS HVO staff to enter hazardous areas? 

person in protective gear using a spectrometer on the rim of Halema‘uma‘u crater
This photo shows an HVO scientist working in the hazardous closed area of Hawai‘i Volcanoes National Park. The scientist is using an instrument to measure the composition of the gases being emitted during Kīlauea Volcano's ongoing summit eruption in order to better evaluate the hazards and understand the eruptive activity. The scientist is equipped with safety gear, is wearing a gas mask (respirator), helmet, eye protection and other PPE, and is in constant communication with USGS and NPS staff. (Public domain.)

The mission of the USGS Hawaiian Volcano Observatory (HVO) is to monitor the active volcanoes in Hawaii, assesses their hazards, issues warnings, and advance scientific understanding to reduce impacts of volcanic eruptions. HVO personnel conduct mission-critical research in the hazardous and closed area of Kīlauea's summit to fulfill this mission, with permission and in partnership with the National Park Service. During the recent eruption, HVO staff are collecting data related to earthquakes, volcanic gas emissions, ground deformation, and fissure/lava lake behavior, in order to understand how the eruption is evolving and to assess hazards at Kīlauea's summit. This information is shared with the National Park Service and emergency managers, who make public safety decisions based on current conditions and hazards.  


Is it safe to breathe volcanic gas or vog?

Be aware that significant sulfur dioxide (SO2) emissions continue and poor air quality is likely in areas downwind of the vents as volcanic emissions react in the atmosphere to form Vog (volcanic air pollution). Vog can create an airborne health hazard to residents and visitors.  

It is very important to take measures to protect yourself if you feel your health is being affected by vog. "Sensitive groups" most likely to experience health impacts include: 

  • people with asthma, lung or heart problems 
  • older adults 
  • infants and children 
  • pregnant women 

For more information, see the following resources:

Color photograph of eruption plume
Aerial imagery collected during a USGS Hawaiian Volcano Observatory overflight at approximately 11:35 a.m. HST. The plume from the ongoing eruption rises above the Kīlauea Volcano's summit, within Hawai‘i Volcanoes National Park. Ha‘akulamanu (Sulphur Banks) is visible in the foreground. USGS photo. (Public domain.)