USGS MAUNA LOA MORNING UPDATE FOR DAY 13

USGS (12.10.22) - The Northeast Rift Zone eruption of Mauna Loa continues. The fissure 3 (F3) vent continues to erupt with a reduced supply of lava and reduced gas emissions this morning. As of 7:00 a.m. today, December 10, a lava pond replaced the fountains at the F3 vent. The pond fed short lava flows that extended only 1.6 mi (2.6 km) from the vent but are already stagnating. The channels below this point appear drained of lava and no longer feed the main flow front. The inactive main flow front remains stalled about 1.7 mi (2.8 km) from the Daniel K. Inouye Highway (Saddle Road) when last measured on the afternoon of December 8. When seen this morning at 7 am, the front appeared to be in the same location. The inactive main flow front still glows at night and may inch northward very slowly as it settles. Sulfur dioxide (SO2) emission rates were also reduced to approximately 30,000 tonnes per day (t/d) as measured on December 8, 2022. The Hawaii Interagency Vog Information Dashboard has detailed information about vog: https://vog.ivhhn.org/. Forecasts for the dispersion of vog can be found on the VMAP Vog Forecast Dashboard: http://weather.hawaii.edu/vmap/new/. Tremor (a signal associated with subsurface fluid movement) continues its slow and steady decline. This indicates that the magma supply to the vent is decreasing. The significance of the reduced supply of lava is not yet clear; it is common for eruptions to wax and wane or pause completely, but none of the 8 recorded eruptions from Mauna Loa’s Northeast Rift Zone returned to high eruption rates after those rates decreased significantly. Nevertheless, the Hawaiian Volcano Observatory continues to closely monitor the current activity. There is no active lava within Moku'āweoweo caldera nor the Southwest Rift Zone. We do not expect any eruptive activity outside the Northeast Rift Zone. ---- END OF USGS UPDATE ---- Map and caption from USGS: The Northeast Rift Zone eruption of Mauna Loa that began the evening of November 27, 2022, continues as of December 9, 2022 (twelfth full day). One active fissure, fissure 3, feeds lava flows downslope to the north. HVO field crews and USGS analysts have accurately mapped some of the most active flows, displayed in red here, along with older flows further uprift, in part of Mokuʻāweoweo caldera, and in the upper summit region southwest of the caldera. Lava flow length was measured by tracing the continuous active channel shown in yellow here and then extending the measurement to the distal lava flow extent measured in satellite data. The total area covered is less than reported in previous days due to refined mapping efforts.