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Volcano Watch: Volcano collapses mark beginning and end of USGS scientist’s career

  • U.S. GEOLOGICAL SURVEY photos

    Left: Horseshoe-shaped crater of Mount St. Helens in 1980, formed by a landslide that removed the top of the volcano. The crater is about 2 km (1.2 mi) wide and the floor is about 600 m (1,970 ft) below the crater rim. Right: Halema‘uma‘u nestled in the summit crater of Kilauea Volcano on Aug. 1, the day before the last collapse event. The Hawaiian Volcano Observatory building is visible at the far right.

My 37-year stint with the U.S. Geological Survey — 16 years at the Cascades Volcano Observatory and 21 at the Hawaiian Volcano Observatory — ends this month.

I feel privileged to have spent a long career observing volcanoes, supporting my colleagues and striving to help people understand the potential impacts of eruptions. Upon reflection, I’m struck by the extraordinary “collapse” events that bookended my career, beginning in 1981 at Mount St. Helens and ending this year at Kilauea Volcano.

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It took only minutes for the top and north flank of Mount St. Helens volcano to collapse in a massive landslide May 18, 1980. The fearsome eruption that followed led to the creation of CVO — modeled after HVO — for scientists to focus long-term investigations and keep a watchful eye on Cascade Range volcanoes.

My journey with volcanoes began there as a surveyor in the debris-clogged river valleys downstream from Mount St. Helens. Soon thereafter, I volunteered to serve as media liaison for CVO. Fifteen years later, I moved to Hawaii to coordinate and develop HVO’s website.

This month, my USGS career ends on the heels of the collapse of Halema‘uma‘u and adjacent caldera floor at the summit of Kilauea. The collapse occurred as an enormous outpouring of lava on the volcano’s lower East Rift Zone 40 km (25 mi) away buried more than 700 homes and 35 sq km (13.7 sq mi) of land with flows as thick as 25 m (80 ft).

Halema‘uma‘u was eventually deepened by more than 500 m (1,600 ft) and widened (east-west) by 1.8 km (1.1 mi), equivalent to a volume loss of 0.9 cu km (1.2 billion cu yds). As magma drained from the summit reservoir, the overlaying crater floor collapsed piecemeal more than 60 times, dropping more than 2 m (6.5 ft) with each event. Each of these collapses released energy equivalent to that of a magnitude-5 earthquake.

Many eruptions in the U.S. and abroad, some with dire consequences, spanned the volcano-collapse bookends of my career. Only four years into my work at CVO, the 1985 eruption of the Colombian volcano Nevado del Ruiz killed more than 25,000 people when lahars (volcanic mudflows) swept down several river valleys.

Thousands of people had, for many decades, unknowingly built their communities on lahar deposits from earlier eruptions of the volcano. This eventually created the dilemma faced by Colombian authorities when the volcano awakened a year before the deadly eruption: How long could evacuation of thousands of people be delayed to minimize economic upheaval and political costs of a too-early evacuation or false alarm?

This dilemma is universal for current emergency management authorities and elected officials as increasing numbers of people live and work on the slopes of volcanoes or within areas known for potential volcanic hazards.

The dilemma also creates increasing challenges for scientists to improve their capabilities to monitor and interpret volcanic behavior so they can issue more accurate and timely warnings of eruptions and potential consequences. They also must effectively communicate the results of their work before, during and after eruptions to raise awareness of volcano hazards to an increasingly interested and demanding media and public.

There have been many successful responses to sudden periods of volcanic unrest since the Nevado del Ruiz tragedy. Two eruptions stand out for me because bold actions taken by officials and scientists saved thousands of lives: Mount Pinatubo in the Philippines in 1990 and Mount Merapi in Indonesia in 2010 (https://volcanoes.usgs.gov/observatories/hvo/hvo_volcano_watch.html?vwid=57). Many USGS colleagues were directly involved in helping scientists in both countries.

USGS work on volcanoes, primarily in the U.S. but also abroad, is possible because of the long-term public investment in our nation’s five volcano observatories. The ever-growing knowledge and experience of observatory personnel with different volcanoes and types of eruptions are invaluable for helping prevent future volcano emergencies from becoming volcanic disasters.

I bid a fond farewell to my colleagues at HVO and the other four U.S. volcano observatories, as well as other volcano scientists, emergency professionals, educators, land managers, naturalists and media with whom I’ve had the pleasure of working.

And to everyone in Hawaii who has supported and challenged HVO and participated in dozens of community meetings during the past few years, mahalo nui loa (many thanks) for your sincerest aloha!

Volcano activity updates

At Kilauea’s lower East Rift Zone and summit, seismicity and ground deformation remain low. Active lava has not been seen within the fissure 8 cone since Sept. 5 and the high rates of seismicity and deflationary deformation at the summit stopped abruptly on Aug. 4. Hazardous conditions still exist in the lower East Rift Zone and at the summit. Residents in the lower Puna and Kilauea summit areas should stay informed and heed county Civil Defense closures, warnings and messages (http://www.hawaiicounty.gov/active-alerts).

No collapses at Pu‘u ‘O‘o have been observed during the past week.

The combined sulfur dioxide emission rates at Kilauea’s summit, Pu‘u ‘O‘o and lower East Rift Zone is less than 300 tonnes per day — lower than at any time since late 2007.

The USGS Volcano Alert level for Mauna Loa remains at Normal (https://volcanoes.usgs.gov/vhp/about_alerts.html).

HVO continues to closely monitor Kilauea and Mauna Loa and will report any significant changes on either volcano.

Daily Kilauea updates are posted at https://volcanoes.usgs.gov/volcanoes/kilauea/status.html. Monthly Mauna Loa updates are posted at https://volcanoes.usgs.gov/volcanoes/mauna_loa/status.html.

Three earthquakes with three or more felt reports occurred in the Hawaiian Islands this past week: a magnitude-3.1 quake at 12:05 p.m. Oct. 1, 28 km (17 mi) west of Pepeekeo at 19 km (12 mi) depth; a magnitude-3.4 quake at 10:46 a.m. Sept. 30, 21 km (13 mi) east-northeast of Honaunau at 5 km (3 mi) depth; and a magnitude-4.0 quake at 12:05 a.m. Sept. 28, 11 km (7 mi) south-southeast of Kapaau at 22 km (14 mi) depth. Small aftershocks from the May 4 magnitude-6.9 earthquake are still being generated on faults located on Kilauea’s south flank.

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Visit HVO’s website (https://volcanoes.usgs.gov/hvo) for past Volcano Watch articles, Kilauea and Mauna Loa updates, volcano photos, maps, recent earthquake info, and more. Call 808-967-8862 for a Kilauea summary update. Email questions to askHVO@usgs.gov.

Volcano Watch (https://volcanoes.usgs.gov/hvo/hvo_volcano_watch.html) is a weekly article and activity update written by U.S. Geological Survey Hawaiian Volcano Observatory scientists and affiliates.

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