USGS MAUNA LOA MORNING UPDATE FOR DAY 9

USGS - The Northeast Rift Zone eruption of Mauna Loa continues. One active fissure, fissure 3, is feeding a lava flow advancing slowly northward toward the Daniel K. Inouye Highway (Saddle Road). The lava flow has reached relatively flat ground causing it to slow down significantly over the past several days, as expected. As of 5:00 a.m. today, December 6, the flow front was about 1.93 mi (3.1 km) from the Daniel K. Inouye Highway (Saddle Road). There continued to be several small overflows from main channels recorded over the past day and a brief surge at the flow front yesterday morning. During the past 24 hours, the lava flow advanced at an average rate of about 68 feet per hour (21 meters per hour), about twice the rate for the past several days. Over shorter periods, the advance rate varied from 62 to 90 feet per hour (18.8 to 27.4 m per hour). The lava flow remains active and is continuously supplied from the fissure 3 vent. Advance rates may be highly variable over the coming days and weeks. On the flat ground between Mauna Loa and Mauna Kea, lava flows advance more slowly, spread out, and inflate. Individual lobes may advance quickly, and then stall. Additional breakouts may occur if lava channels get blocked upslope. There are many variables at play and both the direction and timing of flow advances are expected to change over periods of hours to days, making it difficult to estimate when or if the flow will impact Daniel K. Inouye Highway. Sulfur dioxide (SO2) emission rates of approximately 120,000 tonnes per day (t/d) were measured on December 4, 2022, and remain elevated at this time. The International Volcanic Health Hazard Network has detailed information about vog: https://vog.ivhhn.org/. Forecasts for the dispersion of vog can be found on the Mauna Loa Vog Forecasting Dashboard: https://vog.ivhhn.org/content/mauna-loa-eruption Pele's hair (strands of volcanic glass) fragments are being wafted great distances and have been reported as far Laupāhoehoe. Tremor (a signal associated with subsurface fluid movement) continues beneath the currently active fissures. This indicates that magma is still being supplied to the fissure, and activity is likely to continue as long as we see this signal. 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 ---- Image from Andrew Hara