Kīlauea erupted in and near Nāpau Crater on the middle East Rift Zone of Kīlauea, within Hawai'i Volcanoes National Park, from September 15-20, 2024.
Timeline of eruption events:
Magma intruded beneath the ground near Makaopuhi Crater—a well-known magma storage region on Kīlauea’s middle East Rift Zone on September 14. HVO published a Status Report alerting the public and partners to the activity, which was accompanied by hundreds of earthquakes and ground deformation.
PHASE 1: a brief eruption occurred west of Nāpau Crater on the middle East Rift Zone between 9 and 10 p.m. HST on September 15. 2024. Infrasound sensors in HVO’s monitoring network recorded strong signals indicative of gas or steam venting. At the same time, HVO’s seismometers recorded weak but sustained low frequency tremor. Although an eruption could not be confirmed visually Sunday night by webcams or satellite thermal data due to heavy rainfall, the geophysical data indicated that an eruption could be taking place. That night, some residents in nearby communities also reported strong sulfur or burning smells. The alert level and aviation color code for Kīlauea is raised to ORANGE/WATCH. During an overflight the next morning, geologists observed that a 480-meter (1600-foot) long fissure had covered 16,500 square meters (4 acres) with about 20,000 cubic meters (about 5 million gallons) of lava. Lava was no longer flowing on the surface as of Monday, but magma was still moving underground as detected by seismometers, tiltmeters and GPS.
PHASE 2: NOAA GOES satellite thermal imagery and HVO webcam imagery detect that the eruption has resumed around 6 p.m. HST on September 16. Interestingly, no changes were detected in other monitoring datasets. Fissures from this phase of the eruption produced lava fountains and flows that gradually decreased through the night. But activity would soon resume.
PHASE 3: Between 4 and 5 a.m. HST September 17, infrasound signals, a GOES satellite thermal anomaly, and webcam imagery indicated that the eruption had resumed. After sunrise, HVO scientists on a helicopter overflight observed new vents had opened in Nāpau Crater, with several lava fountains approximately 10 meters (yards) high generating lava flows on the floor of Nāpau Crater. This eruptive phase was more vigorous, l longer lived and continued at gradually decreasing levels through Wednesday afternoon. In total, the fissure system has stretched over 1.6 kilometers (1.0 miles) of the East Rift Zone, with lava flows now covering 18 hectares (44 acres).
PHASE 4: At 3:15 p.m. HST, on September 18, new eruptive fissures opened west of Nāpau Crater. A monitoring camera deployed by HVO field crews with permission from Hawaiʻi Volcanoes National Park recorded “lava falls” cascading down the northwest walls of Nāpau Crater. Vigorous activity continued and by the morning of September 19, about 2/3 of Nāpau Crater floor had been covered with new lava. As of 10 a.m. HST on September 20 morning, phase 4 eruptive activity had ended.
Kīlauea erupted in and near Nāpau Crater on the middle East Rift Zone of Kīlauea, within Hawai'i Volcanoes National Park, from September 15-20, 2024.
Timeline of eruption events:
Magma intruded beneath the ground near Makaopuhi Crater—a well-known magma storage region on Kīlauea’s middle East Rift Zone on September 14. HVO published a Status Report alerting the public and partners to the activity, which was accompanied by hundreds of earthquakes and ground deformation.
PHASE 1: a brief eruption occurred west of Nāpau Crater on the middle East Rift Zone between 9 and 10 p.m. HST on September 15. 2024. Infrasound sensors in HVO’s monitoring network recorded strong signals indicative of gas or steam venting. At the same time, HVO’s seismometers recorded weak but sustained low frequency tremor. Although an eruption could not be confirmed visually Sunday night by webcams or satellite thermal data due to heavy rainfall, the geophysical data indicated that an eruption could be taking place. That night, some residents in nearby communities also reported strong sulfur or burning smells. The alert level and aviation color code for Kīlauea is raised to ORANGE/WATCH. During an overflight the next morning, geologists observed that a 480-meter (1600-foot) long fissure had covered 16,500 square meters (4 acres) with about 20,000 cubic meters (about 5 million gallons) of lava. Lava was no longer flowing on the surface as of Monday, but magma was still moving underground as detected by seismometers, tiltmeters and GPS.
PHASE 2: NOAA GOES satellite thermal imagery and HVO webcam imagery detect that the eruption has resumed around 6 p.m. HST on September 16. Interestingly, no changes were detected in other monitoring datasets. Fissures from this phase of the eruption produced lava fountains and flows that gradually decreased through the night. But activity would soon resume.
PHASE 3: Between 4 and 5 a.m. HST September 17, infrasound signals, a GOES satellite thermal anomaly, and webcam imagery indicated that the eruption had resumed. After sunrise, HVO scientists on a helicopter overflight observed new vents had opened in Nāpau Crater, with several lava fountains approximately 10 meters (yards) high generating lava flows on the floor of Nāpau Crater. This eruptive phase was more vigorous, l longer lived and continued at gradually decreasing levels through Wednesday afternoon. In total, the fissure system has stretched over 1.6 kilometers (1.0 miles) of the East Rift Zone, with lava flows now covering 18 hectares (44 acres).
PHASE 4: At 3:15 p.m. HST, on September 18, new eruptive fissures opened west of Nāpau Crater. A monitoring camera deployed by HVO field crews with permission from Hawaiʻi Volcanoes National Park recorded “lava falls” cascading down the northwest walls of Nāpau Crater. Vigorous activity continued and by the morning of September 19, about 2/3 of Nāpau Crater floor had been covered with new lava. As of 10 a.m. HST on September 20 morning, phase 4 eruptive activity had ended.