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Mt St.
Helens: An Eruption Remembered
May
18, 1980
(A
Memoir of Sorts)
I grew up in
Tornado country… I
recall: candlelit shopping for—with the power
out—emergency supplies…filling water containers...heating soup over a
candle…waiting in
cellars…viewing the wake of destruction. And before the storm there's
an eerie deadness—a surreal moment.
|
| I'd
been in Oregon less than six
months when Mount
St. Helens greeted
me in
a big loud voice. Hello! It was a jaw-dropping experience; amazing,
thrilling, terrifying, and utterly surreal. Aren't volcanoes supposed
to be on tropical islands? The lava pumping out in red rivers, or at
least in red rivulets? And we'll board the re-floated pirate ship while
Nemo goes
down with the
Nautilus? Well… no. |
—Mount St. Helens received its
Anglophone name from Briton Commander George Vancouver. The mountain
was named for Baron St.. Helens, Alleyne Fitzherbert, then British
ambassador to Spain. Vancouver and the crew of the H.M.S.Discovery
spent a the years of 1792 to 1794 exploring the northern portion of the
Pacific coastline. (The cities of Vancouver, British Columbia, in
Canada, and Vancouver in Washington State (across the Columbia River
from Portland, Oregon) are named for Commander Vancouver.)
—Captain Nemo (the Nautilus was his
submarine) is a character that appears in the works of Jules Verne. (20,000 Leagues
Under the Sea and Mysterious Island) Both have been
filmed (the
first five times—one an
animated version, the
second six times, and had a TV
series as well). Mysterious Island (1961) was a
favorite of mine as a youth, and definitely had a impact on me—in
several ways. And this reference constitutes a major spoiler as this
is, in fact, how the story ends.
|
Climatic setting and fantasy aside,
there are different
types
of
volcanoes. Some do spout lava, hurling blobs of molten rock
into the
air, creating rivers of fire. Some violently blow out craters, then
ooze lava slowly, building domes, the mountain gradually reforming.
Cascade volcanoes are mostly the second type. They ferociously blow
pyroclastics (basically any eruption ejected volcanic rock), gases
(some toxic), steam, and ash; and create lahars, with dome-building
phases between these
eruptions.
(See
a graphic/chart illustrating the different volcanoes types.)
Earthquake-like¹ activity (harmonic tremors
aren't normal earthquake
tremors) presage an eruptive-stage's onset…
|
—The Hawaiian Islands (probably
the type most familiar to people) are all shield volcanoes; formed nearly
exclusively of repeated very liquid lava outpourings, sometimes
accompanied by fire fountains of spouting lava, possibly hundreds of
feet high, but to a more localized effect. These are actually Earth's
largest mountains. Volcanoes such as St. Helens, Hood, Rainier, and Mt
Fuji (with which St. Helens was often compared prior to the 1980
eruption) are composite or stratovolcanoes; comprised of
alternating layers of ash, lava, cinders, tephra, and the evocatively
named blocks and bombs. Cascade volcanoes tendency to explosive
eruptions is due to the chemical composition (lots of silica) of the
magma and accompanying gases, as well as to a greater concentration of
gas being present. This region's underlying magma periodically changes
composition, and, so, we can have both explosive and occasionally
non-explosive eruptions. It's all in the mix. Shield volcanoes are
usually more predictable than composite; eruptions tend to be more
localized (although lava flow can be extensive) and are non-explosive.
Lava produced by composite volcanoes tends to be more viscous than that
produced by shield volcanoes. A common by-product of composite
volcanoes is the lahar (mudflow), which can be of any size and are
quite destructive. They can also occur without the volcano being in an
eruptive phase, usually spawned by earthquake¹ activity.
Composites are steep sided, symmetrical, and generally regarded as the
most pleasing in shape.
Essential facts about stuff that confuses people: Lava is molten rock
above ground, while Magma is molten rock below ground. Pyroclastics are
any eruption ejected volcanic rock. Pryoclastic flows are explosive
eruptions of ash (pumice) and gases.
Volcano
Types
Cascade
range Volcanoes and Volcanics
Cascade
Range Volcanoes: Interactive
Graphical
Map (Center the
mouse on the red triangles or you'll
end up back at the index.]
America's
Volcanic Past- Cascade Range
Miscellaneous
Volcanic facts
Glossary:
Volcano and Hydrologic
Hazards, Features, and Terminology
Glossary
of Volcano and Related Terminology |
¹ While the overall area (the zone along
the Juan de Fuca subduction plate) is seismically active (for the last
36-million years) the primary area of earthquake activity is between
Mts Hood, in Oregon, and Rainier (pronounced Ray-Near'), in Washington.
On average a 'felt' earthquake (one people notice without equipment
readings) occurs on Hood every two years. However, there are actually
quakes on the mountain far more frequently. Generally they occur in
swarms, a series of small quakes (3-3.5M each) clustered closely
together (in time). The hotspot of activity is the southern flank, just
south of the summit. Prior to St. Helens eruption the most active
mountain, and probably the most likely to be next to erupt is Mt. Adams
near St. Helens
|
March 20, 1980: A 4.1-magnitude quake
hits the
andesite-dacite volcano
geologists call MSH. Klickitats called it Louwala-Clough,
smoking
mountain. It rumbles off and on for the next seven weeks, with multiple
quakes per hour. Worrisome cracks appeared in the glaciers. March 27,
obscured by cloud cover, a large steam event creates a 250-foot crater
at the summit, and a pressure bulge between two fissures on the north
flank. A second crater soon merges into the first. The bulge grows
5-feet per day, to over a mile in length, half-mile in width, and up to
450-feet high. Minor events plague the month of April. Safety zones are
established, with road blocks costing almost $4000 a day to maintain.
It's claimed
eruption is imminent, but
frustrated scientists and
government representatives fear people aren't taking it seriously.
There's just enough activity to entertain the rubbernecks taunting
death by crowding the restricted zone margins—mild earthquakes and some
venting—insufficient to genuinely frighten. Maps showing ways into the
zone, past the road blocks, disseminate. Clandestine sightseeing has
become a challenge—danger ignored. Evacuated citizens agitate to
return home. The town of Cougar (the nearest community, 8-miles away)
found, at various times, portions of or the
whole town within the
restricted zone. They protest, chide authorities, swipe at scientific
warnings, block the highway, threaten to sue.
U.S. Geological
Survey (USGS) vulcanologist
David Johnston warns that
if the bulge doesn't stabilize there's extreme danger of a
mammoth-sized avalanche. “This mountain is a powder keg, and the fuse
is lit, but we don't know how long the fuse is.” Various agencies tried
to balance cost and safety—briefing frequency lessens, monitoring staff
is reduced. Johnston lobbies for an expansion of the restricted area,
rather than its contraction.
April 30: The
restricted area expands into two
zones: red, with no
public access; and blue, with restricted access. To get monitoring
equipment closer a new USGS station, Coldwater II, is established on a
ridge 5-miles north of the summit.
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|
May 17: A brilliantly clear blue day,
with the
same promised tomorrow.
That night three men camped in different places on Coldwater:
David Johnston (30)—substituting for a colleague—manned the station;
near him, loaned—to remotely trigger photos—from The Columbian
(Vancouver, Washington's newspaper) is photographer Reid Blackburn
(27); farther up is Washington's Military Department Emergency
Management Division's observer, Gerry
Martin (64).
May 18, 1980: At
8:32am a 5.1-magnitude quake
begins the mountain's
violent eruption—its first since 1857. David
Johnston excitedly
radioed to report the
event. “Vancouver,
Vancouver, this is it.” He was shortly thereafter swallowed by the
blast of the eruption, vanishing forever.
Reid
Blackburn also died.
|
—Jerry, a retired
military man and ham radio operator, was on May 18, 1980, 3 days short
of his 65th birthday.
—David's
death is particularly affecting. Enthusiastic, very passionate, a good
scientist....he saved lives...and he was snuffed out—robbed by the very
thing which should have provided him the greatest fulfillment—right at
the very moment the most exciting phase began.
|
| Above them, on the ridge, Martin, in
the midst of his daily radioed
report, told those listening what he'd just seen. “The camper and the
car just over to the south of me are covered. It's going to get me
too.” It did. |
| In
all, 57 people are known to
have died that day—many
bodies were never recovered. The wildlife was devastated—an estimated
5000 black-tailed deer, 200 black bears... The total loss of birds and
animals is placed around 1.5-million, while over 12-million salmon
fingerlings alone perished in destroyed fish hatcheries. Some 230-square-miles
of forest
toppled,
blown down along the contours of
the land, like whorl patterns in hair at a head's crown. The volcano's
blast reached up and slicked back the mountain's hair. It is impossible
to enumerate the loss of the other plant life or insects. The dollar
amount for damage is placed around $1-billion. |
—Escapees reported sightings of
unidentified others within the eruption zone who remain unaccounted
for. Had they come from elsewhere without informing anyone as to where
they were going they may have been reported missing distantly. Other
bodies are known to lay hidden beneath layers of mud and ash—such as
Johnston, Martin, and Truman, none of whom were found (nor are they
likely to be). One woman's body was recovered because of sunlight
glinting off her wedding ring—only her hand extended above the surface.
Even cadaver dogs, at times, had trouble locating the more accessible
corpses.
—Coincidentally, some 230-plus
estimated species of plants had grown within the blast zone prior to
the eruption.
—Weyerhaeuser lost some
68,000-acres of timber in the eruption, adequate it's estimated to have
constructed 300,000 2-story houses. Weyerhaeuser salvaged enough timber
to have built 80,000 3-bedroom homes.
|
| The north flank of the less than
50,000-year-old
mountain had exploded
(unexpectedly laterally) with the force of 500 Hiroshima bombs (at
600mph), reducing its height by more than 1,300-feet. An angry jinn was
released. A lightning laced column of steam and ash rose 80,000-feet in
less than 15-minutes—spreading into that ominous mushroom cloud.
|
—A jinn is a Genie. |
| The
generated 660° heat sterilized the
soil along the course of the
blast. There are more forces to clock: the lateral-blast of steam,
gases, and pyroclastics moved at 300mph; the largest landslide in
recorded history at about 150mph; while later pyroclastics flows were
slower at 50-70mph. |
—Strange foreign bacteria
appeared in the sterilized waters of Spirit Lake for a time after the blast. Now days
there are oversized fish. |
Eruption Damage²
was
wide-spread: 185-miles
of public roads gone, 27 bridges damaged, 200-plus homes destroyed,
people
trapped—many stories of dramatic escapes and rescues emerged over the
ensuing
months. And stories of those who didn't... Spirit
Lake disappeared
under a deluge of pumice and mud that took the life of Harry
Truman (84),
who'd remained with special permission, refusing to leave his lakeside
home. The bed of the Toutle River's North Fork became the channel of a
gigantic landslide as the mountain fell apart. The river, now a wall of
fast moving mud—known as a lahar—swept along everything encountered as
it spread westwards beyond its now clogged riverbed to overrun the
lower Columbia—reducing its channel by 26-feet—stranding 31 ships. Day
turned to night—a swirling chaos, a thick grittiness that blinded, and
choked, and stung. That's not hyperbole—it was devastation. In Spokane,
as if a record blizzard had hit, tons of pyroclastics rained down.
People struggled just to get home, bent against the wind, with scarf
crossed faces—trying to see, trying to breathe. Ash fell over
900-miles away, 550-tons the first day alone. The darkness
extended 85-miles east to Yakima, where
it lasted 12 hours, and beyond.
The eruption
lasted for 9 hours.
|
—Some burrowing animals survived; while
much along the southern
part of the mountain, and surrounding area, went unscathed. See also ² below.
—Spirit Lake, located below the mountain's northern
flank, received its name from natives likening mist
rising off the surface to ghosts. The lake's surface area is
actually larger now, with its new thick sedimentary ash layer raising the lake's surface to a
higher altitude, where, spreading
wider while conforming to the slope of the mountainsides, the lake grew.
—Harry
had a well stocked cave he'd planned to retreat to, with his
cats. However, the abruptness of the eruption would have made it quite
impossible for him (or the cats) to reach the cave in time.
—Route 90 from Seattle to Spokane
was closed
for a week due to the ashfall. (Spokane is pronounced
Spō-can'.) Also,
FYI, ash plays havoc
with internal combustion engines and is hard (slick) to drive on.
—It took 10-weeks to cleanse
Yakima of ash, at an estimated
costs of $2.2-million. The ash had to be shoveled and swept up, then
carted away everywhere it fell. (Yakima is pronounced
Yak'-uh-mah.)
|
²If you didn't open that link
above, please,
do
so now. It is an extraordinary summary of the eruption, listing
losses, but also statistics
on magnitudes, mph, depths, etc. More information on totals, this
time with an economic focus, can be found here.
|
|
Those first few days we divided time
between
TV
coverage and standing
outside staring towards the great mushroom cloud. Sales of simple paper
painters' facemasks skyrocketed. The ash took months
to
settle out, a
fine layer gathered on everything, and stayed. We lived lee side of the
blast, many miles south—didn't matter—we got ash. Each period of
renewed activity on the mountain added to the total. It spawned a new
industry—ash made mementos, or just simply, ash in a bottle. Gen-u-ine
volcano ash! Get it while it lasts. They found Reid Blackburn's car—ash
filled. And all the particulates in the air made for one spectacularly memorable
sunset
after another.
With great
satisfaction we watched wildlife slowly
return
to nibble the
shoots of plants struggling to crack that layer of ash on everything.
Each early evidence of the landscape's rebirth, its inhabitant's
return, a media event. Nevertheless, you can still drive through miles
of ash-shrouded trees lying exactly where the
eruption forced them.
|
—Ash high in the
atmosphere actually circumnavigated the globe multiple times. Also, it
would be
redistributed by
wind, rain, even tremors, spreading where it had already been
cleared, time and time again. It's estimated
that over
2.4-million-cubic-yards (or about 900,000-tons) were removed from
Washington State highways and airports. Five ash dumps—the equivalent
of debris dumps or landfills but containing ash only—were
specially created to stockpile ash, which can be used in
construction. Other
ash was taken to disused quarries and
other dumps.
—I often say a good sunset needs
clouds to show off. This adds drama, but also the color isn't nearly as
visible otherwise, nor as varied. Sunsets happen because light passing
through the atmosphere at an oblique angle causes lots of refraction
and scattering (light bouncing about at various
angles) which reflects as (visible light) various portions of the spectrum's red
end, and is seen as various shades of reds,
oranges, pinks, and purples. More airborn particulates (dust, clouds
(moisture
droplets)) causes more scattering. That means that the
colors you see in the clouds are being generated within the clouds and
aren't just an extension of the sky colors. So, as I said, a good
sunset
need clouds to show off.
—For a time the return happened
in bits
and drabs, but
then, quite suddenly, within a short space of time, all the previous
resident species returned pretty much en masse. This was not what had
been expected to happen and was a pleasant surprise. (Some of Spirit
Lake's inhabitants have apparently been introduced deliberately,
although no one has come forward to take responsibility.
Scientists have
theory about Spirit Lake's big fish. (KATU))
—The monument, part of Gifford Pinchot National
Forest, has visitor centers within it
and a few more stand outside. Some aren't open during winter, but
multiples also allow,
if
volcanic activity necessitates, creation of red zones that still permits
public access to at least one VC. It lets each VC to have a slightly
different focus or special features. Many activities other than viewing
and learning about the volcano
are available in the monument and forest area. Information on planning a visit
is found lower on this page.
—They're also involved in global
research, sharing knowledge with researchers in other parts of the
world.
|
Activity on
the mountain has renewed. It does
from time to time. The
lava dome is now taller than a 30-story building. Spirit Lake is
larger, but shallower, pushed up and out by ash sediment at its
bottom—its surface a raft of rotting logs. Coldwater II, now Johnston
Ridge, is topped by a visitor center and is, when not closed by
volcanic activity, the closest the public is allowed to the now mile
wide 2000-foot deep crater. (Johnston
Ridge Observatory Cam) The National Press Photography
Association has established the Reid Blackburn Scholarship. And we have our memories.
--Remember St Helens (The Columbian) This
site has pieces both from the newspaper
as well as from individual contributors.
--20th
Anniversary (EMD) These are pieces written
by the Emergency
Management Division's personnel of their memories of the events during
the eruption and during the search for survivors.
--Mount St. Helens
Remembered Seattle Times. More focused on
the
elasped 20-years than the eruption and its immediate aftermath.
[If you should find any similar
sites (listing groups of memories like
these two do) please let me know by using the email link at the main
entrance to this site.]
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Always, we acknowledge the disaster
could have
been much worse. Had the
eruption occurred on another flank or later in the day (during logging
activities on adjacent Weyerhauser lands)… Spared: the Columbia River
Gorge, Portland, Vancouver… And while MSH remains a constant
reminder of what
may yet come,
much closer still is
the mighty presence of Mount
Hood—far from
extinct—and it too will blow, someday.
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—It should be made clear that an
extreme
explosive eruption like that of May 18, 1980, is unlikely for the mere
fact that such a huge portion of the mountain is actually gone—much
of what happened can't be
repeated. Not for a very long time.
—There will be severe property
damage
regardless or what type of eruption may come—or its force;
but with the lessons learned, and today's technology,
there should be
sufficient time in which to evacuate. Loss of human life should be
minimal
to nil. There's not much that can be done about the flora and fauna
though. Damage to property and the area's infrastructure will be
extensive. Hood's last eruption was about 200-years-ago, or relatively
shortly before Lewis & Clark arrived in the area.
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For further
information on the eruptions of Mount St. Helens check out these news
sources
Mount
St. Helens News (A NewsLIB
service user site -- links to MSH news from around the world.)
KATU's
Mount St. Helens Team 2 coverage (Local ABC
affiliate's
special coverage section.)
May 18, 2005
The Return
It had been
some years since I was actually up on the mountain, before all the
improvements for visitors were complete. Instead of a well paved
highway, with turn lanes at each visitor center and viewpoint to keep
traffic flowing, it had been up a single lane (with wide spots for
passing on-coming traffic) unimproved road through a murky forest until
we break the tree line. When Jimmy Carter visited the mountain he
described the vista the volcano provided as a moonscape, but a
moonscape would not have included the mile after mile of blown down
forest. It's not enough to say all the trees are laid out flat, ridge,
after ridge, after ridge of them; it's the seemingly endless ranks of
jagged spikes revealing the ripped trunks that illustrate the power and
violence of that brief time in which all these trees fell,
230-square-miles toppled, almost simultaneously. And everywhere and
everything an unrelenting gray, gray, gray; smothered in ash, an
infinite and eternal bleakness. Emotions evoked by the sight can be
nothing but intense and extreme. This you take away with you, and it
stays with you.
Over the intervening years since the big eruption of May 18, 1980, many
changes have occurred on the mountain. Human improvements include the
obvious, from repair or construction of roads and bridges, to creation
of a series of visitor centers; and the not so obvious like the
apparent surreptitious reintroduction of fish to Spirit Lake. Nature
too contributes; the flora and fauna populations rebound and even
flourish. We've seen it all on TV. Yet those remembered onsite images
remain imprinted into your psyche. There's only one way to truly
appreciate the changes, to go there and stand amid the devastation as
it is undone.
August 14, 2005
At last, I'm standing on the mountain again. Is it possible that this
is the same place? It must be, for matchstick blow down remains, and
jagged spikes still thrust upwards, the silt-like ash has washed out of
some of the landscape, but only to make the grit, the angular chunks,
more apparent than before. But over the fallen trees flowers bloom, and
about the base of spikes encircling clumps of flowers climb—fireweed,
lupines, Indian Paintbrush, Queen Anne's Lace, and more...spatterings
of white, yellow, red, purple, and blue. And more spikes abound, those
of leaves and stems, and bushes. It's as though nature is
determined to camouflage the destruction. Given enough time this denial
resolves itself as fact. The planet heals itself, as always, if given
half a chance. And I just cant get over all these flowers. Each new
face the mountain presents impresses itself indelibly upon any human
observer.
Rock Slab
Growing at Mt. St. Helens Volcano (Nasa, Astronomy
Picture of the Day, 2006 May 9. Dan Dzurisin, Cascades
Volcano Observatory.) [Strains of Also Spake Zarathustra fill my
head.]
Added September, 12, 2005
Should
visiting MSH, or the area, be on your
agenda, or if you want to know more about the area, see below for links
to maps, advisory & conditions, visitior
information and tourism sites.
©2005
Mig Archey
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