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Volcano Awareness Month 2021 Program – When will Mauna Loa erupt next?

January 28, 2021

In this talk, USGS Hawaiian Volcano Observatory geologist Frank Trusdell, who has studied Mauna Loa for two decades, presents a roughly 40-minute talk about Earth’s largest volcano: Mauna Loa.

Because Mauna Loa has been quiet for almost 30 years, residents may not be aware that Mauna Loa is an active volcano. When Mauna Loa erupts, it is capable of disrupting lives and commerce throughout the Island of Hawai‘i. What can we learn from Mauna Loa’s past eruptions? What are the signs we need to look for in the future that might portend the next eruption of the world’s largest active volcano? Join USGS Hawaiian Volcano Observatory geologist Frank Trusdell, who has studied Mauna Loa for two decades, as he presents his talk about Earth’s largest volcano.

Video Transcript
(Public domain.)


Other Island of Hawaiʻi virtual Volcano Awareness Month 2021 programs available: 

Video Transcript
What’s happening at Kīlauea Volcano?On December 20, 2020, an eruption began in Halema‘uma‘u at Kīlauea Volcano’s summit, ending a two-year eruptive pause. The water lake that appeared at the bottom of Halema‘uma‘u in late July 2019, which had grown to be over 50 meters (55 yards) deep and more than 10 acres in surface area, quickly vaporized and was replaced by a growing lava lake. The eruption began as three fissure vents in Halema‘uma‘u and has remained dynamic. In this talk, USGS HVO scientists who monitor the eruption with permission from Hawai‘i Volcanoes National Park will share their insights and observations as of January 21, 2021. Were there eruption precursors? What does the new eruption mean for hazards at Kīlauea’s summit? How is the lava lake monitored and what is known about it? Join USGS Hawaiian Volcano Observatory scientists David Phillips, Matt Patrick, Tricia Nadeau, Ingrid Johanson, and Peter Dotray as they answer these questions and more.Talk section timestampsIntro and HVO update – David Phillips – 00:22Geology update – Matt Patrick – 04:43Volcanic gas update – Tricia Nadeau – 16:43Ground deformation update – Ingrid Johanson – 27:23Seismology update – Peter Dotray – 43:24Exit and closing comments – David Phillips – 59:22
Video Transcript
USGS volcano observatories in 2020: Review of the past 10 years and a look to the futureTalk by Tina Neal–USGS Alaska Volcano Observatory geologist and former USGS Hawaiian Volcano Observatory Scientist-in-Charge. Talk originally presented at the American Geophysical Union Fall Meeting 2020.Many 2010 decadal forecasts for USGS volcanology were correct, including increased application of social science into observatory operations; improved interagency coordination; expanded monitoring tools and data sharing. Progress often occurred in conjunction with significant eruptions (e.g., Bogoslof 2017, Kīlauea 2018). Beyond event-related breakthroughs, we expect that sustained strategic planning and investment – much already underway – will drive the next decade of progress in observatory science and operations. The 2017 National Academy of Sciences ERUPT report identified critical science questions, priorities for research, and new ways for the entire community to collaborate. For USGS, 2019 Congressional authorization of the National Volcano Early Warning System (NVEWS) set in formal motion a more integrated USGS volcanology program to improve observatory interoperability, expand 24/7 operations, and broaden opportunities for data collection, dissemination, and targeted research by the larger community. The NSF Community Network for Volcanic Eruption Response (CONVERSE) initiative is catalyzing USGS-academic partnerships to maximize science during event response. An international Volcano Observatory Best Practices effort is developing standards and protocols. Several US funding initiatives are supporting modernization of observatory programs and infrastructure. While volcano-specific expertise will remain critical, by 2030, USGS volcano observatories will be increasingly seamless. Staff will work virtually on common platforms to visualize and interpret data. Nodal seismic arrays, inexpensive microsensors, new satellites, and unoccupied aerial systems will increase the flexibility and reach of monitoring, research, and response. Propelled by computer and data science, reliable smart alarms to detect precursory signals will be common. Field, laboratory, and model-derived understanding of volcanic systems will inform routine use and continued development of forecasting frameworks and dynamic hazard assessments. These collective developments will improve delivery of actionable information to decision makers and those at risk via communication methodologies that keep pace with the rapid evolution in how information is best shared.
Video Transcript
Lava flow forecasting aided by remote sensing during the 2018 Kīlauea lower East Rift Zone eruptionTalk by Hannah Dietterich–Alaska Volcano Observatory geologist. Talk originally presented at the American Geophysical Union Fall Meeting 2020.This talk includes information that was preliminarily shared with emergency responders during Kīlauea Volcano’s 2018 lower East Rift Zone eruption. The 2018 Kīlauea lower East Rift Zone eruption on the Island of Hawai‘i effused 0.9–1.5 cubic kilometers [0.2–0.4 cubic miles] DRE [dense rock equivalent] of lava, destroying infrastructure and homes across more than 30 square kilometers [11.5 square miles] of the lower Puna District. Over more than three months, lava erupted from numerous fissures and produced rapid and dramatic topographic changes; this had significant implications for tracking lava flow emplacement and assessing the ever-changing areas at risk from lava inundation as the eruption progressed. We integrated probabilistic lava flow modeling with remote sensing of topographic change and flow dynamics to provide timely data and forecasts to emergency managers. Flows were modeled from active vents and channel overflow locations over frequently updated topography using the DOWNFLOW model and similar codes based on steepest-descent paths, while approximating flow thickness and ponding. These tools produced flow routing forecasts, while flow advance forecasts were based on measured advance rates. Up-to-date elevation data was primarily derived through repeated surveys by small unoccupied aircraft systems, airborne syn-eruptive lidar and single-pass interferometry surveys, as well as daily mapping of flow extents and thicknesses using a variety of methods. Fast topographic data processing and rapid modeling allowed for flow forecasts to be issued promptly and with improved accuracy during eruption response. To retrospectively assess these efforts and the importance of updated topography, we compare real-time eruption forecasts with later flow mapping, as well as equivalent simulations over pre-eruptive topography. Our results demonstrate how the evolving lava flow field influenced later flow routing and highlight the value of repeat high-resolution topographic surveys for hazard response. Topographic monitoring of the eruption through time also captured the evolution in lava volume and morphology, providing a critical dataset for understanding lava flow dynamics.
Video Transcript
The largest gravity changes ever recorded: Continuous gravity monitoring of the onset of Kīlauea’s 2018 eruption Talk by Mike Poland–USGS Yellowstone Volcano Observatory Scientist-in-Charge and former USGS Hawaiian Volcano Observatory geophysicist.Talk originally presented at the American Geophysical Union Fall Meeting 2020. Eruptive activity at Kīlauea Volcano, Hawaiʻi, in April–May 2018 occurred at sites that were well monitored by continuous gravity. Draining of the lava lake from the summit eruptive vent starting May 1, recorded by a gravimeter on the vent rim, was accompanied by a drop of ~1300 microgals over 9 days. At the rim of the Puʻu ʻŌʻō eruptive vent, 20 km [12 miles] down the East Rift Zone from the summit, a gravity decrease of ~200 microgals over 8 minutes, followed by an increase of ~350 microgals over the subsequent 9 minutes, accompanied the formation of an eruptive fissure on the flank of the cone on April 30. About 45 minutes later, a decrease of ~1500 microgals occurred over 2 hours as lava drained from the vent. These gravity changes are the largest ever recorded anywhere in the world.The evacuation of the summit and Puʻu ʻŌʻō eruptive vents provided opportunities to image the vent geometries, which were used to model the mass changes at the two locales. At the summit, joint modeling of gravity, lava level, and vent geometry indicate a best-fitting density of 1700 kilograms per cubic meter for the lava within the vent. There is no record of lava level over time at Puʻu ʻŌʻō, but the gravity data combined with the vent geometry can be used to reconstruct that process, suggesting that the lava had a density of ~1900 kilograms per cubic meter and that in 2 hours a bulk volume of 11 x 106 cubic meters drained from the cone. The pre-collapse gravity decrease and subsequent increase at Puʻu ʻŌʻō are more difficult to model given the lack of other constraining data. We hypothesize that the gravity fluctuation is due to the emplacement of an eruptive fissure on the west side of the cone immediately prior to the collapse. The gravity decrease represents the opening of a dry crack, and the gravity increase is the subsequent filling of that crack with magma that was denser than the spatter that makes up much of the cone.These data highlight the importance of continuous gravity for monitoring volcanic activity. Not only do the data provide important constraints on lava density, they can also be used to estimate the rate and volume of lava accumulation or withdrawal and can detect transient eruptive fissures, even in the absence of other observations. Without such data, our knowledge of the processes occurring at Puʻu ʻŌʻō during the crucial opening hours of the eruptive sequence would be as cloudy as the weather during that period.





Friday, January 29: A virtual walk through Kīlauea Volcano’s summit history

Join USGS Hawaiian Volcano Observatory scientist emeritus Don Swanson on a virtual walk, during which you learn about the past 500 years of Kīlauea Volcano’s history as revealed by rocks, craters, and cracks. This virtual walk will be released in three parts, covering different sections of the Keanakākoʻi Crater trail. Along the walk, Don points out and explains some of the features that formed during the 2018 summit collapse events, as well as the best publicly accessible display of explosive deposits erupted from Kīlauea around 230–370 years ago, one of which probably relates to an important oral tradition. Don also shows two contrasting vents for the July 1974 eruption, highlights the thick deposit of pumice and scoria erupted in 1959, and ponders the origin of Keanakākoʻi Crater. You can visit the Hawaiʻi Volcanoes National Park website ( to learn about walking the 2-mile round-trip Keanakākoʻi Crater trail, which begins at the Devastation Trail parking lot on Crater Rim Drive in Hawaiʻi Volcanoes National Park (Map:

Plumbing the depths of Kīlauea Volcano - POSTPONED

One of the key goals of volcanology is to monitor the movement of molten rock (magma) beneath the Earth’s surface.  Most volcanoes have their main storage area for magma a mile or two beneath the volcano in the Earth’s crust.  Kīlauea Volcano is very different and stores magma within the volcano itself, about a mile beneath its summit.  This is only possible because Kīlauea is so enormous it can store a large volume of magma.  In addition, the amount of magma moving through the system is so high that it doesn’t stay within the volcano long enough to crystallize.  To the average person, and quite frankly often to volcanologists as well, the pattern of volcanic vent locations at Kīlauea's summit or along its rift zones looks a lot like the game “Whack-a-mole,” where the eruptions seem to randomly appear.  However, there are patterns and our concept of what Kīlauea’s magma plumbing system looks like has changed significantly over time. After large eruptions like the 2018 eruption in Puna, Kīlauea’s plumbing appears to undergo significant re-organization.  While the recent reappearance of lava at Kīlauea’s summit happened quickly, summit activity was not unexpected.  ​Join geologist Ken Hon as he discusses what scientists are looking for now to better understand what Kilauea may do in the future.

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