USGS-HVO Monthly Kilauea Update, 2/6/20

Current Volcano Alert Level: NORMAL Current Aviation Color Code: GREEN Activity Summary: Kīlauea Volcano is not erupting. Monitoring data for January show variable rates of seismicity and ground deformation, low rates of sulfur dioxide emissions, and only minor geologic changes since the end of eruptive activity in September 2018. Observations: Monitoring data have shown no significant changes in volcanic activity during January. Rates of seismicity over the month were variable but within long term vales. Sulfur dioxide emission rates are low at the summit and are below detection limits at Puʻu ʻŌʻō and the lower East Rift Zone. The pond at the bottom of Halema'uma'u, which began forming on July 25, 2019, continues to slowly expand and deepen. As of early February, dimensions are: 95 meters by 194 meters or approximately 310 feet by 640 feet. Current depth is approximately 25 meters or 82 feet. Over the past month, eight deflation-inflation (DI) events occurred beneath the summit, slightly less than the prior month. Since early March 2019, GPS stations and tiltmeters at the Kīlauea summit have recorded deformation consistent with slow magma accumulation within the shallow portion of the Kīlauea summit magma system (1-2 km or approximately 1 mile below ground level). During January, deformation rates at Kilauea summit appeared to have decreased somewhat. Gas measurements show continuing low levels of sulfur dioxide, consistent with no significant shallowing of magma. Some amount of sulfur dioxide is being dissolved into the summit lake; work continues to try and quantify this process. Farther east, GPS stations and tiltmeters continue to show motions consistent with slowed refilling of the deep East Rift Zone magmatic reservoir in the broad region between Puʻu ʻŌʻō and Highway 130. During January, deformation rates in this region appeared to have decreased somewhat. Monitoring data do not suggest any imminent change in volcanic hazard for this area. In addition to motion along the East Rift Zone, the south flank of Kīlauea continues to creep seaward at elevated rates following the May 4, 2018 M6.9 earthquake near Kalapana. HVO continues to carefully monitor all data streams along the Kīlauea East Rift Zone and south flank for important changes. Although not currently erupting, areas of persistently elevated ground temperatures and minor release of gases are still found in the vicinity of the 2018 lower East Rift Zone fissures. These include steam (water), very small amounts of hydrogen sulfide, and carbon dioxide. These conditions are expected to be long-term. Similar conditions following the 1955 eruption continued for years to decades. Hazards: Hazards remain in the lower East Rift Zone eruption area and at the Kīlauea summit. Residents and visitors near the 2018 fissures, lava flows, and summit collapse area should heed Hawaii County Civil Defense and National Park warnings. Lava flows and features created by the 2018 eruption are primarily on private property and persons are asked to be respectful and not enter or park on private property. The Hawaiian Volcano Observatory (HVO) continues to closely monitor geologic changes, seismicity, deformation, and gas emissions for any sign of increased activity at Kīlauea. HVO maintains visual surveillance of the volcano with web cameras and field visits. Additional messages and alert level changes will be issued as warranted by changing activity. Background As of June 25 2019, Kīlauea Volcano has been at NORMAL/GREEN. For definitions of USGS Volcano Alert Levels and Aviation Color Codes, see: https://volcanoes.usgs.gov/vhp/about_alerts.html. Kīlauea remains an active volcano, and it will erupt again. Although we expect clear signs prior to the next eruption, the time frame of warning may be short. Island of Hawaiʻi residents should be familiar with the long-term hazard map for Kīlauea Volcano (https://pubs.usgs.gov/mf/1992/2193/) and should stay informed about Kīlauea activity.