GPS World

Tag: Kilauea volcano

  • GPS key to monitoring Kilauea eruption, lava lake

    GPS key to monitoring Kilauea eruption, lava lake

    2020 Ends with a Bang as Kilauea Volcano Erupts

    Beginning in September, GPS stations in Kilauea’s upper East Rift Zone observed increased rates of uplift, higher than they have been since the end of the eruption in 2018. According to the U.S. Geological Survey’s Hawaiian Volcano Observatory, earthquake rates increased in late November.

    On Dec. 2, GPS stations and tiltmeters recorded a ground deformation quake at Kilauea’s summit accompanied by earthquake swarms.

    Then on Sunday, Dec. 20, a magnitude 4.4 earthquake struck on Kilauea’s south flank and three fissure vents broke open inside the caldera. Fountaining lava at these vents is estimated to be up to 82 feet high. The vents are feeding lava flows into the base of Halema‘uma‘u crater, which is being filled with lava. The lava lake has been rising several yards an hour since the eruption began at 9:36 p.m. Sunday. The eruption is currently confined to the crater.

    According to the observatory, “The water lake at the summit of KIlauea has boiled away and an effusive eruption has commenced, with three vents in the wall of Halema‘uma‘u crater generating lava flows that are contributing to a growing lava lake at the base of the crater.”

    As of Dec. 29, the summit eruption continued with the western vent active (the other vents have been covered by the lava lake). At 3:45 a.m. HST, field crews measured the lava lake as 179 meters (587 feet) deep, about 650 feet below the rim.

    Shortly after 9:30 p.m. HST Dec. 20, an eruption began at the summit of Kīlauea Volcano in Hawaii. Red spots indicate fissure vents feeding lava into the bottom of Halema‘uma‘u crater. Lava coverage is 32 feet higher than the water in this photo (base map is from imagery collected on Sept. 23, 2020).
    Shortly after 9:30 p.m. HST Dec. 20, an eruption began at the summit of Kīlauea Volcano in Hawaii. Red spots indicate fissure vents feeding lava into the bottom of Halema‘uma‘u crater. Lava coverage is 32 feet higher than the water in this photo (base map is from imagery collected on Sept. 23, 2020).
    The water lake at the base of Halema‘uma‘u crater has been replaced with a growing lava lake. View from the west rim of Kīlauea Caldera just before 5 a.m. HST on Dec. 21, 2020. A 59-foot fountain joins two other fissures to feed a growing lava lake at the base of Halema‘uma‘u crater. (Photo: USGS)
    The water lake at the base of Halema‘uma‘u crater has been replaced with a growing lava lake. View from the west rim of Kīlauea Caldera just before 5 a.m. HST on Dec. 21, 2020. A 59-foot fountain joins two other fissures to feed a growing lava lake at the base of Halema‘uma‘u crater. (Photo: USGS)
    The interactive USGS monitoring map shows GPS stations situated on and around Kilauea as well as volcano activity. (screenshot taken at 12 p.m. HST on Dec. 21).
    The interactive USGS monitoring map shows GPS stations situated on and around Kilauea as well as volcano activity. (screenshot taken at 12 p.m. HST on Dec. 21).
    An HVO geophysicist deploys a GPS receiver on the Kilauea caldera floor to measure changes in ground motion. A volcanic gas plume rises in the background. (Photo: USGS)
    An HVO geophysicist deploys a GPS receiver on the Kilauea caldera floor to measure changes in ground motion. A volcanic gas plume rises in the background. GPS and tiltmeter data show contraction in the upper portion of the East Rift Zone (an area between Kīlauea’s summit and Pu‘u ‘Ō‘ō). (Photo: USGS)
  • GPS actively monitoring Kilauea’s eruptions, lava flows

    GPS actively monitoring Kilauea’s eruptions, lava flows

    GPS measurements are playing a key role in monitoring the erupting Kilauea volcano in Hawaii.

    The floor of the Pu’u ‘O’o Crater started to collapse on April 30, following weeks of uplift and increasing lava levels within the cone and seismicity in the East Rift Zone. The eruptions began on May 3, when a magnitude 5 earthquake struck, causing further collapse of the crater.

    The Hawaiian Volcano Observatory (HVO) has monitored volcanic activity on the islands since 1912. The HVO is operated by the U.S. Geological Survey (USGS) and is issuing continuous updates on Kilauea.

    The HVO is closely monitoring the biggest fissures in what is known as the lower East Rift Zone. Geologists are onsite to track ongoing and new fissure activity and the advance of lava flows.

    Kilauea eruption map as of 8 a.m. HST, May 21. Shaded purple areas indicate lava flows erupted in 1840, 1955, 1960 and 2014–2015. (Photo: USGS)

    GPS stations monitor land movement of Kilauea. The Big Island’s most active volcano has erupted nearly continuously for more than three decades.

    “Magma supplied to the Lower East Rift Zone was indicated by the northwest displacement of a GPS monitoring station,” the HVO said in its May 26 status update, but the station ceased movement a few hours later, telling a new story.

    “Magma continues to be supplied to the Lower East Rift Zone; however, a GPS instrument near the Lower East Rift Zone is no longer moving, suggesting that the rift zone is no longer inflating in this area,” the HVO stated. “Elevated earthquake activity continues, but earthquake locations have not moved farther downrift in the past couple of days.”

    Map of GPS stations installed near the Pu’u O’o vent on Kilauea. (Photo: USGS)

    The GPS stations also monitor earthquake activity associated with the volcano. For instance, the May 4 magnitude 6.9 earthquake resulted in seaward motion of 1.5 feet along portions of Kīlauea’s south flank as measured by GPS stations across the volcano.

    “Because active volcanoes make for unstable land, highly sensitive seismometers come in handy to track the frequency and strength of micro-earthquakes,” the HVO explained. “Global Positioning System (GPS) devices and another satellite-based technology, InSAR (Interferometric Synthetic Aperture Radar), map ground deformation (inflation and deflation) to within a fraction of an inch while tiltmeters measure slope from ground level. Together, these technologies help track lava’s movement underground and help pinpoint where it might break through the surface.”