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      ۻ   ۻ  ۻ ۻ   ۻ ۻ ۻ ۻ
      ۻ ۻ ۺ ۻ  ۺ ۺ ͼ ۻ
      ɼ ۺ ۺ ۻ ۺ ۺ ۻ   ɼ
      ۻ ۺ ۺ ۺۻۺ ۺ ͼ   ۻ
      ۺ  ۺ ۺ  ۺ ۺ ۺ ۺ ۺ ۻ ۺ  ۺ
      ͼ  ͼ ͼ  ͼ ͼ ͼ  ͼ ͼ ͼ ͼ  ͼ

   Ŀ    Ŀ    Ŀ Ŀ    Ŀ Ŀ Ŀ  Ŀ
        Ĵ                        Ĵ      
                                    
           Ŀ    Ŀ Ŀ          Ŀ  Ŀ
                Ĵ Ĵ               Ĵ  Ŀ
                                     
                      Ŀ Ŀ Ŀ     
                       Ŀ           
                         

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      Ŀ Ŀ     Ŀ Ŀ  Ŀ  Ŀ Ŀ
                   Ĵ             
              o                
                     ERUPTION HISTORY


1820            RAINIER         Ash(?)
1820-1854       RAINIER         Andesite pumice
1841            RAINIER         Ash(?)
1843            RAINIER         Ash(?)
1846            RAINIER         Ash(?)
1854            RAINIER         Ash(?)
1873            RAINIER         "Clouds of smoke pouring from
                                highest peak
1879            RAINIER         "Brown, billowy clouds"
1882            RAINIER         "Brown, billowy clouds"




       Mt.  Rainier, of western Washington.  Few who have ever seen her
will ever forget her.  Towering 14,410 feet over the Puget Sound, Mt.
Rainier is the most conspicuous object on the horizon--when it's not
obscured by clouds, that is.  From Seattle to Port Orchard to Bremerton
to Vashon Island, Mt. Rainier is a stunning sight to behold on a crisp
Washington morning.  Mt. Rainier supports the largest glacier system in
the lower 48 states (26 are officially named) and enjoys a status as
a National Park.  The mountain's base is beautiful, gilded with wildflowers,
mosses and heather.  Her summit is equally beautiful, covered year-round
with snow.

        Rainier is nothing more than tranquil beauty, until you notice
her twin summit craters (see CRATER.GIF), with clean edges free of snow
and ice.  These craters have been known to belch a little heat and steam from
time to time, and that keeps them free from winter's grip.  Yes, Mt. Rainier,
in all her beauty, is a slumbering volcano--asleep now for 111 years, and
counting.  By contrast, Mt. Saint Helens slept for 123 years before
roaring to life in 1980.

        The United States Geological Survey has a "volcano watch" on
Rainier.  Residents of Tacoma and other Seattle suburbs routinely practice
"volcano drills."  Rainier WILL erupt again.  But,   when???

͸
 Detailed, scientific information on Mt. Rainier is difficult to     
 find.  I used "FIRE MOUNTAINS OF THE WEST" and "FIRE AND ICE,"      
 both by Stephen L. Harris to prepare this report.  I wish to thank  
 Mr. Harris for his dedication to the study of the Cascade range     
 volcanoes, and for two extremely informative and fascinating books! 
;
    Compiled in August, 1993, by Jim Coleman, Sysop, The NASA MLP BBS
                  Text written by Jim Coleman

                        Brought to you by:
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 ۲              THE  NASA  MLP                ۲ 
 ۲ (206)871-3965       Hours: Forever, Amen!! ۲ 
 ۲            The ULTIMATE trip!              ۲ 
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                       TABLE OF CONTENTS:

           Opening Remarks and Eruptive History of RAINIER
                    The Rock is Gonna Fall On Us
                          In the Beginning
                       The Baby Volcano Grows
                          RAINIER  Matures
                         After the Glaciers
                     Destruction of her Summit
                   Building of the Present Summit
                       Recent Thermal Activity
                      The USGS "Volcano Watch!"
                   When MT.  RAINIER Erupts Again!
                        Visiting MT. RAINIER
                     Glossary of Geologic  Terms
                        Volcano--Jimmy  Buffet





Ŀ
                              THE ROCK                                    

        This is an interesting message that I found in the Seismology
Conference on my BBS (MLPNET) (SciFacNet).  It just about sums it all
up.  Enjoy this, and then be prepared to delve into the fascinating
history of beautiful Mt. Rainier!

The NASA MLP BBS  Node 2 871-3965 08-08-93 14:06
Name: JIM COLEMAN


Date: 08-08-93 (14:06)              Number: 11845 of 11845 (Refer# NONE)
  To: ALL
From: JIM COLEMAN
Subj: Rock is Falling
Read: (N/A)                         Status: PUBLIC MESSAGE
Conf: Main Board (0)             Read Type: GENERAL (-)

This is YOUR invitation to join the SEISMOLOGY conference, where
earthquakes HERE and abroad are reported and discussed!


It is always fun when you do your research, collect your facts and
approach people with the news that it is a good idea to buckle up and
prepare for the worst.  I now know how Noah felt.  <G>  Washington state
is number four in the entire country in seismicity, and there is strong
physical evidence of MAJOR events in this area.  But, as the USGS says
in one of it's publications: "The public has largely forgotten the quake
of 1965, and the population in the Puget Sound area has more than
doubled since that time."

I certainly don't scream that a huge quake is imminent, but it *IS*
smart to be prepared.  My brother just kinda chuckled it off, but he did
let me secure his water heater for him.  (This is the same one that I
warned when he moved into his house that the garage needed repair.
During the Inauguration Day storm, he lost the roof and half the
contents of his garage.  :)

I did find this VERY interesting song, that I feel relates to what we
are doing in this conference.  The lyrics are (C) Harry Chapin Estate
and (C) Elektra Records:


        THE ROCK

"THE ROCK IS GONNA FALL ON US!"
He woke with a start.
And he ran to his mother
The fear dark in his heart.
And he told her of the vision
That he was sure he'd seen
But she said "Go back to sleep, son,
You're having a bad dream.

"Everybody knows the rock leans over the town
Everybody knows that it won't tumble to the ground
Remember Chicken Little said the sky was fallin' down
Well, nothin' ever came of that
The world still whirls around."

"THE ROCK IS GONNA FALL ON US!"
He stood and told the class
The professor put his chalk down
And peered out through his glasses
But he went on and said, "I've seen it high up on the hill-
If it doesn't fall this year
Then very soon it will."

(The professor remarks:)
"Everybody knows the rock leans over the town
Everybody knows that it won't crumble to the ground
We've more important studies than
Your fantasies and fears
Everybody knows that rock's been perched
Up there a hundred thousand years."

"THE ROCK IS GONNA FALL ON US!"
He told the magistrate,
"I believe that we can stop it,
but the time is getting late.  You see,
I've done all the research
My plans are all complete--"
He was showing them contingencies
When they showed him to the street.

(They said:)
Everybody knows the rock leans over the town
Everybody knows that it won't tumble to the ground
Everybody knows of those who say the end is near
Everybody knows that life goes on
As usual 'round here."



He went up on the mountain beside the giant stone
They knew he wasn't sane
So they left him all alone.
He'd given up enlisting help
For there was no one else
He spent his days devising ways to stop the rock himself.

One night while he was working
Building braces on the ledge
The ground began to rumble,
The rock tumbled off the edge.

"THE ROCK IS GONNA FALL ON US!
Brother, you'll be crushed!"
And, indeed, the rock was moving,
Crumbling all the dust.
He ran under it in one last hope
That he could add a prop
And as he disappeared
The rock
Came to
A stop.

The people ran into the street
But all was still
The rock seemed where it always was,
Or where it always will be.
When someone asked where he had gone
They said, "Oh, he was daft.
Who cares about that crazy fool!"
And then they'd start to laugh.

But high up on the mountain
When the wind is hitting it.
If you're watching very closely,
the
rock
slips
a
little
bit.



Just like it does each year under the Puget Sound.  :)
<<<>>>


                                        
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The NASA MLP BBS - Today's Launch Schedule: Seismology, Meteorology,
Hobbies, Electrical Engineering, Chemistry, Current NASA News, Games,
Children's Education, Music, Arts, All facets of Education, TO THE
              LIMIT OF YOUR IMAGINATION!!!



Ŀ
                          IN THE BEGINNING                                


     To witness the birthing of this majestic and powerful volcano, let's
step back in time nearly ONE MILLION years!  Picture the Cascades and
Puget Lowlands WITHOUT Seattle, Bremerton, Tacoma and the cities surrounding
the Puget Sound.  With the exception of the noticeable absence of Mt. Rainier,
the area looks very much the same!  The mountain would eventually be
born on a large, rugged plateau one full mile above sea level, surrounded by
mountain peaks up to 3,000 feet higher!  The recognizeable rivers in the area
(Carbon, Mowich, White and Puyallup) had already scooped out large canyons
branching to the north (toward present-day Seattle) and west toward the
Puget Sound lowlands.  Differences in elevation (from the summits to the
valley floors) was already about 4,000 feet.  Wooly mammoths prowled the
lowlands of the Puget Sound then, sharing the area with an assortment of
other wildlife. (In fact, on August 10, 1993--just yesterday--a small girl
found a genuine wooly mammoth tooth lying on a Puget Sound beach.  No kidding!)

        A series of earthquakes on the plateau gave the first indication that
a powerful volcano was soon to radically alter the landscape.  These quakes
gradually increased in strength and frequency; some of them split the ground
open, and vapor issued from numerous fissures.  The earthquakes continued
until the ground soon vibrated nearly continuously.  The vapor soon transformed
into surging columns of steam.  A cacaphonous roar was produced as one of the
fissures was ripped open and huge chunks of rock were thrown into the air.
Explosion soon followed explosion, and the daytime skies were darkened as ash
and debris was thrown into the air.  Rainier was born, and, by nightfall, a
cinder cone 150 feet high stood where flat ground had existed only the day
before.

        The devastation in the area was complete.  Ash covered everything, like
a layer of dirty snow.  Gone were the pretty firs, snowfields, and clear
alpine streams.  The area looked very much like a desolate, barren moonscape.
Rainier continued to erupt, producing tremendous quantities of pyroclastics
(Greek word for FIRE-BROKEN, referring to fragmented volcanic rock thrown out
during an eruption), mainly hypersthene (a mineral found in basic rocks)--
hornblende andesite pumice.  At night, sparks flew as red-hot rock particles
were thrown skyward, and red hot magma danced against the backdrop of dark
ash in the night skies.  The magma beneath the new mountain had been held under
too much gaseous pressure for far too long; it now literally blasted out of the
maw of the newborn mountain.

        Rainier's pyroclastic cone hit 1,000 feet in height, and the volcano
feel eerily silent for several years.  A variation in the volcano's usual
pattern occurred during this time.  Instead of blasting out skyward,  the
liquid rock rose to the very mouth of Rainier, threatening to spill over and
down its slopes.  This created pressure within the mountain that Rainier could
not stand.  It's sides split open from the foot of the cone to the summit
crater and streams of lava broke free.  An entire side was swept away by this
torrent of molten rock.

        The lava, perhaps 1,800 degrees fahrenheit, spilled into a riverbed
at the mountain's base as it searched for the lowest channel in which to
flow.   The air cooled the lava until it advanced only a few hundred yards
per day, and soon, stopped altogether, congealing at an accumulated depth
of several hundred feet.  The first lava flow (of thousands to come) from
Mt. Rainier was over, but the mountain remained so hot that the winter snows
had no chance of sticking to it.  The mountain grew.

        The Mount Rainier we know in the 20th century is built almost
exclusively of hypersthene-andesite flows, which might lead one to believe
that Rainier was built primarily from the quiet emission of lava.  This, quite
simply, is not true.  Throughout an unknown number of centuries, the volcano
on the plateau where Mt. Rainier now stands erupted quite violently.  There is
evidence of this in the Puget Lowlands where the mudflows derived from this
active volcano at the site of Rainier are interbedded with glacial drift
deposited by the huge ice sheet that moved into the area from Canada, due
north.

        Erosion partially removed Rainier's ancestral cone some 700,000
years ago, and the mountain erupted voluminous lava flows.  At this stage
in its growth, Rainier most likely resembled a large, broad lava dome with
gray, black and red tentacles of andesite snaking out from a central crater.

        It is commonly believed that these flows of lava issued from vents
along the sides of the volcano and travelled many,  many miles.  One such
flow filled the Grand Park River (since vanished) to a depth of 2000 feet,
and a distance of twelve miles!

Ŀ
                        THE BABY VOLCANO GROWS!                           

        Due to the fact that the infant mountain sat atop a complex
series  of ridges and ravines, its lava flows did not simply pile up
around the cone as is the case with other Cascade volcanoes.  Instead,
the flows drained into the nearby valleys.  The Puyallup and Mowich
Rivers were seriously affected as Mt. Rainier looked to drain its magma.
The mountain continued to erupt, issuing molten lava over previous flows
not yet cooled.  These lava flows carried debris with them, which soon
dammed the ancestral rivers and forced them to find new new channels.
The original waterways of the Puyallup and Mowich were soon completely
buried beneath more than 2,000 feet of andesite.  A flow 900 feet deep
and several miles in length on the east side of the mountain deflected the
ancestral White River from its course.  Yet another snaked past Goat
Mountain.  Rainier continued to spew lava, and  major land changes occurred in
the Puget Sound area.

        Eventually, the climate turned much cooler.  Snow started to stick
and accumulate and fell to record depths.  Summers were too short and far
too cool to melt the snowfall, and, soon, canyons and ravines were soon
filling with ice.  Mt. Rainier, sheathed completely in ice, fell into its
longest period of inactivity to date, as if it had frozen to death.  Glaciers
slid down its flanks, carving new paths.  Valleys and ravines were scooped out
and deepened by moving sheets of ice.  Streams of meltwater carried debris
away from Rainier and deposited them in the Puget Lowland.  It was almost as
if the new mountain was doomed to "piecemeal destruction."

        However, as all sleeping things do, the mountain awoke--and with
a fury.  It was quite a catastrophic awakening.  The plug in the volcano's
throat had long since solidified, and the explosions ripped effortlessly
through it, sending debris far and wide over the surrounding area.  The sun
literally disappeared as the ash turned day into night, and fire continued
to spew from the "quiet" mountain.  Steam, meltwater, molten rock and
other debris combined to rush down Rainier's flanks at speeds in excess
of 50 m.p.h.  One flow, on Rainier's north face, managed to consume and
replace an entire glacier 1200 feet thick!  This survives today as
Ptarmigan Ridge, though it is deeply eroded.)

        Through episodes of Pleistocene glaciation, the baby mountain
continued to grow, shaped by the strong forces of fire and ice.  When
Mt. Rainier was dormant, ice carved new trenches in the mountain and
trimmed its shape.  However, sporadic eruptions filled valleys with lava
and its shape was regained.  As time passed, Mt. Rainiers eruptive habits
changed, in that she no longer erupted canyon-filling lava flows, but,
rather, narrow streams of lava which terminated and piled up around
Rainier's cone, giving her a rapid increase in height.  Earlier lava
flows had raced down the slopes and covered areas of a hundred square miles
or so, but the new flows were far more restricted, rarely exceeding a
thickness of 50 to 200 feet.  Finally, Mt. Rainier began to assume the
shape of an elegant stratovolcano.

Ŀ
                         THE MOUNTAIN MATURES                             

        Today, Rainier looms over the Puget Sound at a summit altitude of
14,410 feet.  However, Rainier used to be taller, MUCH taller (see
RAINIER.GIF).  Roughly 75,000 years ago, Mt. Rainier at her maximum size
loomed 16,000 feet above sea level!  In addition, the mountain was most
likely far more symmetrical than it is today, though most scientists doubt
that Rainier was ever a perfect cone (except maybe, at birth) due to the
cutting glaciers.  Rainier was probably high enough to support glaciation
even during the warmest Pleistocene interglaciations.

        New vents opened up on Rainier's north side and built what are
now the eroded remains of Observation Rock and Echo Rock.  Small streams of
lava issued from these vents and continued toward the base of the mountain.
With the exception of this activity, Rainier once again lapsed into a period
of relative inactivity.  Flows of lava occasionally broke through the cone, but
Rainier's emissions were mainly steam and acidic gas.

        Rainer experienced at least three heavy periods of glaciation in
the past 65,000 years.  Each of them significantly impacted the mountain
in terms of erosion.  The last one, in particular, the Fraser Glaciation,
stripped  between 2,000 and 3,000 feet of material from all sides of Rainier's
cone.  When the Pleistocene  glaciers melted away, ONE THIRD OF MOUNT RAINIER
HAD VANISHED!

        Rainier erupted very little fresh lava during this period.  Steam
and various other gases rising from her internal pools of magma converted
much of the summit rock to clay, weakening the summit.  Mount Rainier stood
16,000 feet high at the beginning of the Halocene Epoch.

Ŀ
                         AFTER THE GLACIERS                               

        Since the ice and glacial age, most of Rainier's eruptions have
actually served to tear the mountain down, rather than build it up.

        Between 6600 and 5700 years ago, Rainier was quite different still
than it is today.  Recognizeable outcrops such as Little Tahoma Peak and
Steamboat Prow extended much higher up the mountain and bore only a vague
resemblance to their present-day form.

        With no warning whatsoever, a violent explosion brought major changes
to Rainier's flanks.  The eastern slope of the mountain was loosened and it
plunged into the canyon of the White River.  Condensed steam within the debris
quickly turned the slide into a mudflow hundreds of feet thick, carrying
blocks of andesite up to thirty feet in diameter!

        This mudflow removed yet another layer from Rainier's east side,
exposing hydrothermally altered lavas that lay immediately beneath her outer
shell. Some of these were tinted green, white, sulphur yellow, and/or dull
orange, demonstrating that what once had been solid rock was now soft,
permeable material.

        The steam explosions also triggered a huge avalanche that swept
down the Nisqually Glacier on Rainier's south side.  The avalanche was
soon transformed into a giant mudflow, which rushed through Paradise Valley
in a single wave in excess of 800 FEET in height!

Ŀ
                    THE DESTRUCTION OF HER SUMMIT                         

        Rainier managed to lose more than a fifth of a cubic mile in volume
during the Paradise and Greenwater mudflows, but the loss was insignificant
when compared to the destruction which followed. One of Rainier's most
cataclysmic Holocene eruptions occured some 5700 years ago.

        Even at what would be considered "safe ground," a high plateau
35 miles down the EAST side of Rainier, a wall of rock and mud over 100
FEET IN HEIGHT, MOVING AT ABOUT 40 MPH obliterated everything in its path.

        This disastrous mudflow, the infamous OSCEOLA MUDFLOW is one of the
largest mudflows on record ANYWHERE in the world.    Mt. Rainier's entire
summit, weakened by years of acidic emissions, suddenly collapsed,
disintegrating like the dome of a great sports arena during an earthquake.
Simultaneous steam explosions sent tons of shattered rock over the northeast
flank of the volcano.  Consequently, the undermined summit toppled
eastward, forming a deadly avalanche of hydrothermally altered rock hundreds
of feet in height, which easily overrode the apex of Steamboat Prow.  This
avalanche was so immense that the entire structure of Steamboat Prow was
momentarily completely buried!

        A huge wave of debris washed down the Emmons Glacier between the Prow
and Little Tahoma to flood the White River Canyon while yet another sped down
the Winthrop Glacier into the West Fork of the White River.  They converged
beyond the base of the mountain and extended 65 miles to inundate 125
square miles of the Puget lowlands.  Within a matter of hours, rock that had
once enjoyed an altitude of 16,000 above sea level now lay beneath the chilly
waters of the Puget Sound (about where Puyallup now sits!)  Only very rarely in
Halocene time has a volcanic mudflow affected an area so large, and so far
from its source.

        As one may suspect, Rainier took on a totally new appearance following
the summit collapse.  Rainier's once-stately summit now housed a void, one and
a half to two miles in diameter--a bowl shaped caldera tipped to the east,
that survives to this day!  The highest points on the caldera walls were (are)
on the north, Liberty Cap (14,112 feet) and, on the southwest, Point
Success (14,150 feet).  The western caldera wall, relatively intact, stood
somewhat higher until about 2800 years ago, when another series of mudflows
and rockslides changed the mountain even further.


Ŀ
                    BUILDING THE PRESENT SUMMIT CONE                      

        About 2500 years ago, Rainier introduced a welcomed variation
in her eruptive behavior.  For the first time in 25,000 years, a cycle of
activity began that, in effect, actually repaired some of the damage
done by earlier outbursts.  Volcanoes, particulary Mount Rainier, are
intricate structures, and, by virtue of longevity, not all the volcanic
activity is necessarily destructive!

        Renewed construction began with the discharge of hot ash and
molten breadcrust bombs.  These were blown from vents within the caldera
and they accumulated until the combined weight and bulk sent them
sliding down the west flank of the mountain.  This hot avalanche, at least
200 feet in height traveled down the South Puyallup River valley, igniting
groves of timber on the valley floor.  Engulfed in a flowing mass with a
temperature at least 600 degrees Fahrenheit, many tree trunks were instantly
reduced to charcoal.  Carbon samples from this deposit enabled scientists to
date the eruption that produced it.

        Mt. Rainier next spewed large volumes of pumice, which the winds
carried northeast of the peak to blanket Yakima Park, where it lies a foot
thick.  Following the pyroclastic eruptions, streams of liquid andesite
poured from fissures in the caldera floor and spilled over eastward from the
eastern rim.  These thin tongues of black, glassy lava did not travel very
far downslope, but they were sufficient to cause a very sudden melt of the
Emmons and Nisqually Glaciers.  Once again, devastating mudflows poured into
the White River and Nisqually valleys, raising canyon floors at least 80 feet
above their present levels.  The flows of lava quickly built a miniature
new Mt. Rainier atop the old summit.  As the cone grew, it eventually filled
most of the summit depression left by the catastrophic avalanches of
some 3,700 years before.  This late and rare cone-building (see RAINIER.GIF)
episode most likely required no more than just a few decades.  When complete,
the beautifully symmetrical young mountain sitting atop the ruins of its
predecessor had a base a mile across and a crest that stood at least 1000
feet above the now-buried eastern lip of the old caldera.

        A second, briefer, eruption of lava occured some time after the first,
forming a somewhat larger crater east of the old vent.  1,330 feet across and
perhaps 500 feet deep, this younger crater tilts noticeably to the east.  The
point where the two craters overlap (See CRATER.GIF)--now called Columbia
Crest--marks the highest elevation of Mt. Rainier.

        Were it not for constant heat and steam emission, glaciers
might have already breached Rainier's crater rims.  Occasional brief
eruptions of steam and ash have originated at the summit vents
during the past 2,000 years, the last occuring within historic time.  But,
when compared with the tons of material removed DAILY from the volcano
by mudslides, glaciers, and meltwater, the amount of new lava produced
in recent centuries is negligible.

        Quoted from "Fire and Ice," by Stephen L. Harris--"Our journey into
Mount Rainier's past has shown the volcano growing from a small cinder
cone to an ice-covered giant; from a classic smooth-sided cone to
its present craggy mass.  Although its life-story has already spanned
more than a million years, Mt. Rainier will be with us and our children
for many eons to come."

Ŀ
                      RECENT THERMAL ACTIVITY                             


        Mount Rainier has not has a BONA FIDE eruption in nearly a hundred
years, but the mountain has NOT been entirely at rest.  In addition to
areas of hot rock and active fumaroles on the summit cone, the volcano
still produces occasional hot steam explosions on its flanks.  Reports of
these phenomena seem to have increased in frequency in the past decade.
Beginning in the early 1960's, summer climbers were sometimes startled by
hearing loud explosions and seeing columns of vapor rise from crevices in
the rock.  In 1961, steam blasted a new hole near Gibraltar Rock, sending
a column of pressurized vapor 200 feet into the air and scattering debris
over the nearby Cowlitz Glacier.  This vent remained active throughout
the summer, though diminishing in frequency.  In March, 1965,
skiers were amazed to observe clouds of steam spouting from a ridge above
the Kautz Glacier and setting off an "avalanche."

        A much larger avalanche--the largest in historic time--may have
been initiated by a steam explosion on December 14, 1963.  About noon on
that date, forest rangers 12 miles northeast of the mountain heard a
"very loud, sharp boom in the direction of Mt. Rainier."  When clouds
and falling snow cleared enough for the Rangers to see the eastern slope
through binoculars, they could see a large amount of rock debris covering the
lower Emmons Glacier.

        What the rangers could not perceive from their location was that
approximately 14 million cubic yards of lavas and breccias had fallen from
the north face of Little Tahoma Peak.  Plummeting straight downward for
1700 feet onto the glacier's surface, the avalanche struck with tremendous
force.  Because of its large mass and the steepness of the landing site,
the avalanche shot across the surface buoyed up by a cushion of compressed
air, at speeds up to 100 miles per hour.  When it reached the glacier's snout,
it simply soared up into space.  A stream-guaging station, six feet high,
was untouched as tons of rock hurled by overhead.  Where the upper White River
valley curves or is constricted, the flowing mass of rock and trapped air
surged up canyon walls as high as 300 feet!  When it all finally came to
rest, a HALF MILE FROM THE WHITE RIVER CAMPGROUND, it had travelled some four
miles from its source while dropping over 6,200 FEET in ALTITUDE!  Several
of the boulders transported were as large as buildings!  One measures 60
by 130 by 160 feet and weighs in the neighborhood of 50,000 tons.  Imagine
seeing THAT coming down a ravine, right at you!  :)

        Later studies revealed that at least seven separate rockfalls and
avalanches had occurred in quick succession.  The plywood guage house that
survived the first river of rock was later carried hundreds of feet by
a blast of air escaping from the flank of another avalanche which stopped
a short distance away.  Two square miles of the Emmons Glacier and Upper White
River valley were covered by the rockfalls.  If this would have happened in
the summer months, many hikers could have been killed.

        In August and September, 1967, clouds of water vapor and "steam"
were seen billowing from the cliffs above the South Tahoma Glacier.
During the same period, floods and mudflows repeatedly descended the
Tahoma Creek Valley.  Described as causing a deep rumbling noise and
vibrations of the ground, these small lahars swept large boulders
downstream and generated waves of mud up to 15 feet high.  Further
sightings of steam and smoke rising from the west face of the volcano were
reported in August, 1968, and February, 1969.  These rockfalls and
slurry floods may have been initiated by a steam vent located beneath the
South Tahoma Glacier.

        A more threatening manifestation of Mt. Rainier's internal heat
occurred on the Emmons Glacier during the summer months of 1969.  Between an
elevation of 10,000 and 13,000 feet, the normally intact ice surface broke
into a network of potholes and crevasses.  In some places, gaps in the ice
widened enough to reveal bare rock beneath the glacier.  This melting by sub-
surface heating was brief, however, and by the summer of 1970, new ice and snow
had filled in the caved-in areas. Nonetheless, such melt-depressions on
glaciers, completely unrelated to weather conditions, are the kind of WARNING
TO BE EXPECTED WHEN A DORMANT VOLCANO IS PREPARING TO ERUPT!!!


Ŀ
                        THE USGS "VOLCANO WATCH!"                         

        Because of these, and other signs of geologic restlessness, scientists
at the University of Washington and the United States Geologic Survey keep
a "VOLCANO WATCH" on Mt. Rainier.  In the 1960's the USGS began taking
aerial photographs and infrared images of the summit craters, Little Tahoma
Peak, and the South Tahoma Glaciers.  In addition, seismographs were placed
at various locations on the mountain, one as high as Camp Muir at the 10,000
foot level.  These quake-monitoring stations record swarms of micro-
earthquakes centered beneath the peak, which, should they suddenly increase
in frequency or intensity, could mean that magma is rising in the mountain
conduits toward the surface.  The tremors thus far recorded demonstrate that
some activity indeed DOES continue within Rainier's deep, subterranean magma
chamber.

        The infrared surveys have officially confirmed what mountain climbers
have always known--Mt. Rainier's summit craters are definately hot!  The
zones of the most intense volcanic heat were found along the northwestern
rim of the east crater, the north side of the west crater, and along a
pattern of concentric arcs on the western flank of the summit cone.  A later
survey indicated a possible increase in thermal anomalies along the
southern rim of the west crater, but that may have resulted from imperfections
inherent in the infrared techniques.  In general, the hottest areas correspond
to swaths of exposed rock, which stand out as black patches amid the summit
icefields.

        When geologist and mountaineer Dee Molenaar measured the heat generated
at fumaroles in both summit craters, he found that the steam issues at
temperatures of about 186 degrees Fahrenheit (the boiling point of water at
14,410 feet).

Ŀ
                    WHEN MOUNT RAINIER ERUPTS AGAIN                       

        "Residents of Seattle, Tacoma and adjoining cities have much to
worry about.  An eruption of Mount Rainier, even on a small scale, could
easily obliterate most all of the Puget Sound communities, even burying parts
of Seattle and Tacoma under ash, lava and mud up to two dozen feet thick in
places . . . Even west-sound communities, such as Bremerton and Silverdale,
would be disastrously affected . . ."

        Please, sit back with me and laugh at this.  I spotted this portion
of a message on the Internet, and properly chastised the author for this
far-from-the-truth advisory.  However, this is an attitude that is pervasive
with some of the media; I am sure we've all heard speculation that Mt. Rainier
will scorch and burn our cities, turning them into modern-day Pompeiis.  This
is simply not true.

        Yes, *WHEN* Mt. Rainier blows (after all, it is a matter of WHEN, not
a matter of IF) there will be destruction and possibly death, even in some
settled areas in the Sea-Tac area.  However, it would have to be a
cataclysmic eruption far beyond anything scientists have projected to affect
the west-sound communities, and even to cause Seattle/greater Tacoma much
concern aside from a bit of possible ash fallout.

        Let's examine what could possibly happen when Mount Rainier wakes up
and decides to burp.  There are several different scenarios, and we'll examine
each.

        First, potential loss of life and property has GREATLY increased this
century as more people have settled around the towering Cascade volcanoes
and more people use them for recreational purposes.  From Canada down to
California there are scores of new lumber camps, thousands of new homes,
artificial reservoirs and lakes.  Rainier is no exception.  Most people,
absorbed in the beauty or positive economic impact of the large volcanoes are
unaware, or choose to ignore the danger.  However, it is unlikely that Seattle,
Tacoma, Bellingham and scores of other Puget Sound towns would suffer too
greatly due to the meteorological fact that prevailing winds would most
likely carry the ash fallout east, over the Cascade Range.  Towns downwind,
such as Yakima and Ellensburg could possibly receive damaging fallout.  This
could (among other things) pollute the air, clog machinery, and muddy the water
supply.  Only if Mount Rainier exploded violently (on the scale of the
catastrophic Mt. Mazama eruption 6,600 years ago) would there be a serious
threat to western Puget Sound populations.

        With ejection of pyroclastics restricted to the size of those which
built up the present summit cone 20 centuries ago, any appreciable damage
from Mt. Rainier would most likely be confined to an area 10 to 15
miles immediately downwind from the summit crater.  Of course, curious persons
standing on ridges at a closer range could be in danger, even though they
were out of the path of any lava or mudflows.  Remember, previous Holocene
eruptions have thrown rocks up to FOUR FEET in lenth distances of EIGHT MILES,
or slightly more!

        It is wise to note that there definately *IS* the possiblity that
Rainier will produce an eruption of far greater magnitude than anything
seen in the past 7,000 years.  In that event, no one can accurately predict
what will happen, and I won't be foolish enough to try.  If a huge eruption
such as this seemed imminent, a speedy evacuation to high ground as far as
possible upwind of the volcano would be advised.

        Geologists with the United States Geological Survey keep a "Volcano
Watch" on Mount Rainier now, and continously project what possibly could happen
in the event of an eruption.  Fumaroles along the twin craters of Rainier
have released enough acidic steam to compromise much of the summit, turning
it to opal or clay.  If the summit were to collapse as it did long ago,
another Osceola-type mudflow could result.  This could be the result if
fresh lava were to rise in the eastern crater.  In this event, steam
explosions caused by hot magma in contact with meltwater could conceivably
rupture the crater walls.

        One only has to LOOK at Mount Rainier to see the present danger.  The
mountain towers majestically over populated areas of the Puget Sound (See
TOWERING.GIF), its shoulders and flanks covered with ice and glaciers.  Logic
would suggest that in an eruption (which produces tremendous heat), all that
ice would be shaken loose and melted, and millions of gallons of water
would sweep down the slopes in a deadly rush, obliterating everything in
its path.  This water and debris would find its way into the numerous glacial
rivers in the area, which wind toward the Puget Sound, and, consequently, run
through many populated areas.  Judging by the effects of Mount Rainier's
historical eruptions, the Puyallup, Tahoma, Nisqually and Whiter River valleys
seem to be at high risk in such an event.  There would be a very high danger
from mudflows, which, in the past, have REPEATEDLY swept down through these
valley areas.  Lava flows from Rainier would probably be short, and ashfalls
would extend a few dozens of miles east, northeast, and/or southeast of the
summit crater. The principal danger would be to towns--ORTING, SUMNER,
AUBURN, PUYALLUP, ENUMCLAW, etc.-- which lie on deposits from large,
historical mudflows.

        Should Mt. Rainier blow and you live in one of the adjacent valleys,
catch a ferry to Port Orchard on the west side of the sound and you can sit
with me on the porch and watch the event.  :)


Ŀ
                       VISITING MOUNT RAINIER                             

       ( I would like to thank my friend, Sam McKernan for his help with
this part of this lengthy detailed document.  What follows (well, follows my
comments about visiting an active volcano) are two messages about visiting
Mount Rainier that I pulled out of The NASA MLP Seismology conference.
Thanks, Sam!)

        Okay, you have just read that Mt. Rainier is an ACTIVE volcano,
issuing steam from time to time as it sleeps.  You have read the risks
associated with an eruption, one that will certainly happen sometime in the
future.  Now, you are gonna read a section on visiting the mighty Rainier and,
perhaps even consider driving out to the mountain?  What, you may wonder,
do you think I am nuts???

        Relax.  Even with the destruction accompanying the Mount Saint Helens
eruptions and even with all I've written about mudflows and avalanches and
rushing rivers and lava flows, Rainier is (at this time) still a safe place
to visit.  Volcanic eruptions most always give plenty of notice, and
scientists and communities are usually well prepared for the event.  Take,
for instance, Mount Saint Helens.  Scientists couldn't accurately predict
exactly when she'd blow, but there was plenty of time for evacuations and
planning.  Consequently, loss of life was surprisingly minimal.  Most volcanic
eruptions begin on a small, harmless scale.  For that reason, you need not omit
a trip to Rainier (or any other Cascade volcano) from your vacation
itinerary.  Before a catastrophic outburst were to occur, there would be
numerous clues and unmistakable warning signs, which would give authorities
plenty of time to evacuate the area(s) possibly affected.

        What are the signs?  They are numerous, but include increased steam
emissions, swarms of microearthquakes recorded on seismographs, swelling of
the mountain as indicated on a tiltometer, and the appearance and/or
proliferation of"hot spots" detectable on infrared images.

        Of course, it *IS* remotely possible that a volcano could explode
violently before sufficient evacuation notice was given.  Or that, contrary
to its past behavior, a volcano could erupt far more violently than it had in
the past.  However, unless activity was noted in the recent past, the chances
of this happening are awfully slim, and if this should keep you from visiting
one of the Cascade volcanoes (such as Mt. Rainier) you are only robbing
yourself of a very enjoyable time!

        ENJOY MOUNT RAINIER, THE PRETTIEST OF ALL THE CASCADE PEAKS!!!

Date: 07-20-93 (23:44)              Number: 488 of 615 (Refer# NONE)
  To: ALL
From: SAM MCKERNAN
Subj: MT. RAINIER INFO
Read: (N/A)                         Status: PUBLIC MESSAGE (Echo)
Conf: SEISMOLOGY (6)             Read Type: GENERAL HAS REPLIES


GENERAL INFORMATION

         Mount Rainier National Park is located in southwest
Washington state, 95 miles southeast of Seattle and 83 miles west of
Yakima. Mount Rainier was established March 2, 1899 as our fifth
national park. The park encompasses 378 square miles (980 square
kilometers) Elevation ranges from 1800 feet at the Carbon River
rainforest to 14,410 feet at the summit of the glacier-covered peak.
Approximately 2 million people visit the park each year to enjoy its
most rainforest, giant old growth forest, subalpine meadows, and
glaciers.

INDIANS
         Before the arrival of European explorers, Indian tribes lived
in the lowlands surrounding the mountain. Some tribes called the
mountain "Takhoma," others "Tahoma" with meaning of "high mountain,"
"great snowy peak," or just "the mountain."

EXPLORERS
         The first recorded view of the mountain by a European was
made by the English explore, Captain George Vancouver while exploring
Puget Sound in 1792. He mentioned sighting a "remarkably high mountain
covered with snow." He named the peak after his friend Rear Admiral
Peter Rainier, who never saw the mountain.

THE VOLCANO
         Mount Rainier is a volcano that is believed to be dormant and
not extinct. The volcano began to grow between one half and one million
years ago. The slopes of lava flows on opposite sides of the mountain
projected more than 1000 feet above the present summit. The upper
portion of the cone was probably removed by explosions and landslides.
The current summit, Columbia Crest at 14,410, lies on the rim of the
recent lava cone.

GLACIERS
         There are 25 named glaciers and about 50 small, unnamed
glaciers and ice patches on the slopes of Mount Rainier. Mount Rainier
has the largest single peak glacial system in the United States outside
Alaska. The largest glacier on the mountain is the Emmons Glacier on
the east side. The largest glacier seen from Paradise is the Nisqually
Glacier.

PLANTS
         The forest surrounding the mountain are predominantly
Douglas-fir, western hemlock, red cedar, and several species of true
fir. The meadows above them are summer time celebrations of color as
wildflowers bloom in July and August; their broad vistas are cool and
remote, with majestic sweep and rising snowline, where spring happens
all summer long. In August tiny alpine ecosystems flourish at the toes
of the ice fields.

WILDLIFE
         Animals live in the park include bear, deer, elk, mountain
goats, mountain lions, bobcats, beaver, marmots, squirrels, rabbits,
hammsters and raccoons, and a variety of birds who live in or visit
the park.

WEATHER
         Mount Rainier is often said to create its own weather. It
reaches into the atmosphere and interrupts the flow of the moist
maritime air masses from the Pacific Ocean. This results in great
amounts of rain and snowfall. The heavier rainfalls occur between
October and early May. During the winter of 1971-72, 1,122 inches of
snow fell at the Paradise weather station. Summer temperatures average
in the upper 40's to the mid-70's at Longmire (2,761 feet) and in the
lower 40's to the mid-60's at Paradise (5,400 feet).

FEES
         An entrance fee of $5.00 per non-commercial vehicle is
charged. A fee of $2.00 per person is charged for person entering by
foot, bicycle or commercial vehicle. Golden Age Passports are
available to persons over 62 years old, and Golden Access Passports
are available to disabled and handicapped persons. A park specific
annual pass for Mount Rainier is available for $15.00. The Golden
Eagle Passport annual pass, good in all federal recreation areas
charging an entrance fee, is available for $25.00 per year. A user fee
of $5.00 - $6.00 is charged per night per campsite in the auto camp-
grounds.

AUTO CAMPING
         Five car campgrounds offer 600 campsites for overnight stay in
the park. Campsites are available on a first-come-first-served-basis,
with no reservations. Fees range from $5.00-$6.00 per night. The Cougar
Rock and Ipsut Creek Campgrounds do offer group campsites which can be
reserved, call 206/569-2211. Group fee is $1.00 per person. All camp-
grounds have running water, flush or pit toilets, and individual sites
 with a table and fireplace. Sunshine Point and Isput Creek Campground
are open year round for camping.

BACKPACKING AND HIKING
         Backcountry permits are required for all overnight stays in
the backcountry and wilderness, on a year-round basis. These free
permits are available at hiker information centers, ranger stations
and visitor centers, on a first-come-service-basis. Over 300 miles of
trail throughout the park are available for day hikers and backpackers
to enjoy. The 93 mile Wonderland Trail completely encircles the
mountain, traversing through low forest, subalpine meadows, and over
occasional snow and rock. Higher elevation trails remain snow covered
into July most years.

CLIMBING
         The first recorded climb to the summit of Mount Rainier was
made in 1870 by Hazard Stevens and Philemon Beecher Van Trump from the
south side of the mountain. Each year, more than 3,000 people stand on
the summit of Mount Rainier. Climbers need to be in top physical
condition, and have experience in glacier travel. Climbers must
register with a Ranger before climbing and checkout upon returning.

BICYCLING
         Bicycles are allowed in the park on roads open to the public
and roadways in the campground extreme caution needs to be exercised
due to the very narrow roads. Bicycles are not permitted on any park
trails, including "Mountain Bikes."

BOATING AND FISHING
         Boating and fishing are permitted within the park, and no
licenses are required. Non-motorized boats only are permitted on park
lakes. Fishing regulations for the park are in accordance with those of
the surrounding area waters of the State of Washington. Be familiar
with specific regulations for boating and fishing.

HORSES
         Horses are permitted on nearly 100 miles of park trails.
Trails are most accessible from mid-July through September. Neither
saddle nor pack animals are permitted in auto campgrounds, picnic
grounds or within 100 yards of trail shelters, backcountry campsites or
above such sites and waterways, except where facilities are provided. A
horse trail map is available.

SNOWMOBILING
         Snowmobiles are permitted on designated roadways only, when
such roadways are closed by snow to normal traffic. Snowmobiles are
not permitted to travel crosscountry, on trails or on undesignated
roads. A map of designated snowmobile roadways is available.

RANGER PROGRAMS
         Guided walks and information programs are presented through
the park, see the summer and winter park newspaper or check at the
museum and visitor centers for details. Programs are open to all ages
and abilities.

PARK ROADS
         The road from Paradise to Ohanapecosh is opens mid-June
through early November. Highway 1, and 410 via Cayuse Pass open by late
April most years through December. Chinook Pass opens by early June and
closes in November. The Sunrise road opens to the White River Camp-
ground by mid-June and Sunrise by July 1st. Snowfall may close higher
park roads for a few day in the fall before closing for the winter.

FOOD AND LODGING
         Mount Rainier Guest Services, Inc. operates the Paradise Inn,
National Park Inn, and Sunrise Lodge in the park. The Paradise Inn is
open late May to early October for lodging, meal and gifts. The
National Park Inn at Longmire will be closed for remodeling starting
mid-April 1989 for about a year. The Sunrise Lodge is open for meals
and gifts July-September. For lodging reservations write Mount Rainier
Guest Services. Inc. P.O.Box 108. Ashford. WA 98304 or call
206/569-2275.

         Lodging and food service are available in the local
communities of Ashford, Packwood and Enumclaw. Seattle, Tacoma,
Portland and Yakima also offer lodging and food services.


FOR FURTHER INFORMATION WRITE
Mt. Rainier National Park, Tahoma Woods, Star Route, Ashford, WA. 98304
<<<>>>



         ķ
           Ŀ     Ŀ  Ŀ  Ŀ Ŀ Ŀ     
            Ŀ         Ŀ  Ŀ Ĵ  Ĵ  
                        
                      of GEOLOGIC TERMS             
              from FIRE AND ICE by Stephen Harris   
         Ľ

Aa--    Hawaiian word used to describe a lava flow that is characterized by
        a surface broken into rough, angular "clinkery" fragments.  Good
        examples of these jagged slaggy flows occur along the McKenzie Pass
        Highway between the North Sister and Mt. Washington.
Ash--   fine particles of pulverized rock from an explosion vent.  Measuring
        less than 1/10th inch in diameter (under 4mm), ash may either be solid
        or molten when first erupted.  By far the commonest variety is vitric
        ash, glassy particles formed by gas bubbles bursting through liquid
        magma.  Lithic ash is formed of older rock pulverized during an
        eruption, while in crystal ash each grain is composed of a single
        crystal or groups of crystals with only traces of glass adhering to
        them.  Many ash deposits are mixtures of all three in various
        proportions.
Ash Flow-- A turbulent mixture of gas and rock fragments, most of which are
        ash-sized particles, ejected violently from a fissure or a crater.
        This mass of pyroclastics is normally of very high temperature and
        moves rapidly down the slopes of a volcano or even along a level
        surface.  Extensive ash flows have been erupted from Mt. Mazama,
        Broken Top, and Mount Saint Helens.  When solidified, ash flow
        deposits are often called ignimbrites.  (See pyroclastic flow and
        block-and-ash flow.)
Basalt-- A lava relatively poor in silica and rich in magnesium and ferrictic.
        When poured out in sufficient volume with a high enough temperature and
        gas content, it typically flows long distances from its source and is
        the characteristic lava of most shield volcanoes.  The outpouring of
        highly fluid basalts created the vast inland plateaus of Washington
        and Oregon during Miocene time.
Bergschrund-- A crevasse at the back of a glacier between the glacier and the
        rock headwall, formed by melting and the movement of the glacier.
Block-- Angular chunk of solid rock ejected during an eruption.  Accumulations
        of blocks may form breccia.
Block-and-ash Flow-- Variety of a pyroclastic flow, a turbulent mass of hot
        fragments, varying in size from under 1/10th inch to many feet in
        diameter, which sweeps downslope as a result of a volcanic eruption.
        Block-and-ash flows are commonly caused by the collapse of the side of
        a dome while still hot, as happened with the first Mount Saint Helens
        eruption.
Blocky Lava-- Lava which, when congealed, exhibits a surface broken into large
        angular fragments.  Whereas aa lava has a spiny, scoriaceous crust,
        blocky lava flows have one littered with large boulders.
Blowhole-- A miniature crater, usually secondary in nature to the main vent
        of a volcano, through which gas is discharged.  Blowholes often form
        on the surface of a thick lava flow, the result of rapidly escaping
        gas.
Bomb--  A fragment of molten or semi-molten rock 2.5 inches to many feet in
        diameter which is blown out during an eruption.  Because of their
        plastic condition when first ejected, bombs are often modified in
        shape during their flight though the air and/or by their impact
        with the ground.  As the outer crust cools and solidifies,
        continued expansion of the interior by gas pressure sometimes
        causes cracking, which may form a bomb surface resembling the
        crust of freshly baked bread (breadcrust bombs).
Breccia-- A rock composed of many distinct fragments, often sharp and/or
        angular, imbedded in a matrix of fine material.  Breccias are
        sometimes formed when shattered blocks of volcanic rock are
        transported by avalanches or volcanic mudflows.
Caldera-- The Spanish word for cauldron, a large basin-shaped volcanic
        depression--by definition at least a mile in diameter.  Such large
        depressions are typically formed by the subsidence of volcanoes.
        Crater Lake occupies the best-known caldera in the Cascades.  Calderas
        are to be distinguished from craters, which they always exceed in size.
Cinder Cone-- A volcanic cone built entirely of loose fragmental material
        (pyroclastics).  Most cinder cones are symmetrical, with a circular
        ground plan and steep, regular slopes terminating in a single
        summit crater.  Although the eruptions which build these cinder cones
        are most always explosive, lava commonly flows quietly from the foot
        of the cone.
Clinker-- Rough fragment of lava on the surface of aa flows, so named because
        of its resemblance to clinkers formed in the grate of a furnace.
Cirque-- An ampitheater-like depression in mountain regions, formed by the
        plucking action of glacial ice.
Composite Cone-- Another term for a stratovolcano, a large volcanic cone
        constructed of both lava flows and fragmental material.  All of the
        largest Cascade volcanoes are this type.
Conduit-- The feeding pipe of a volcano, the "throat" through which material
        passes on its way to the surface of the earth.  When filled with
        congealed lava (a plug), a central conduit is often relatively
        resistant to erosion.  As a result, the solidified conduit fillings
        can remain standing as high pinnacles long after the surrounding
        cone has been eroded away.  Mt. Thielsen and Union Peak are good
        examples of such eroded volcanic necks.
Crater-- The bowl-shaped hollow, usually at or near the top of a volcano,
        through which lava and pyroclastics and ejected.  In cross-section,
        most craters are cylindrical or funnel-shaped.
Dacite-- Lava with a high silica content.  Dacites are usually slow moving
        and viscous when erupted and can form flows of exceptional
        thickness.  When unusually thick and pasty, they may form steepsided
        domes, such as Lassen Peak.  The only major stratovolcanoes in the
        Cascades formed principally of dacite lava are Glacier Peak and
        Mount Garibaldi.
Detonation-- An explosion as a result of the combustion of gasses or by the
        abrupt release of gasses from a volcanic vent.
Dike--  Relatively thin walls of solidified lava which cut through, vertically
        or obliquely, the interior of a volcanic cone.  Dikes are formed when
        liquid lava rises to fill cracks or crevasses within the volcano.  Some
        dikes are the congealed feeding pipes of parasitic cones or lava flows.
        They are visible only when exposed by erosion.
Dome--  A rounded protrusion of lava which, when erupted, was too viscous to
        flow laterally and instead piled up above the erupting vent.  When the
        lava mass is an upheaved, consolidated conduit filling, the resultant
        mound is called a plug dome.
Dormant--Literally "sleeping."  The term used to descibe a volcano which is
        presently inactive but which may possibly erupt again, like Mount
        RAINIER of western Washington.  Most of the rest of the Cascade
        volcanoes are also believed to be dormant rather than extinct.
Ejecta--The material thrown out of a volcano.
Engulfment-- The inward collapse of a volcano, perhaps as a result of an
        evacuation of the magma chamber.  The collapse basin thus formed is
        called a caldera.
Eruption-- The process by which solid, liquid, and gaseous materials are
        ejected, usually violently, onto the surface of the earth by volcanic
        activity.  Eruptions range from the quiet overflow of liquid rock
        to the tremendously violent expulsion of pyroclastics.
Eruption Cloud-- The column of gasses, ash and larger rock fragments rising
        from a crater or other volcanic vent.  If it is of sufficient volume
        and velocity, this gasous cloud may reach many miles into the
        stratosphere, where high atmospheric winds may carry it miles from its
        original source.  The eruption cloud from Mount Mazama, for example,
        was probably carried by the winds entirely around the world!
Eruptive Vent-- The opening through which volcanic materials are ejected.
Fault-- A crack or fracture in the earth's surface along which there has been
        differential movement.  It may represent the juncture between two
        adjoining blocks or tectonic plates.  Movement along a fault can
        produce earthquakes, or, in the process of mountain building, can
        release underlying magma and permit it to rise to the surface.
Fissure-- Elongated fractures or cracks on the slope of a volcano, or any
        ground surface.  Fissure eruptions typically produce liquid flows,
        but pyroclastics may also be ejected.
Fumarole-- A vent or opening through which issue steam, hydrogen sulphide,
        or other gasses.  The craters of many dormant volcanoes such as
        RAINIER, Shasta, Lassen and Hood now contain active fumaroles.
        Some give off chemically active fluids or gases which radically
        alter or erode the surrounding rock, changing it eventually into
        such substances as opal or clay.  This process can hasten the erosion
        and eventual destruction of volcanic peaks.
Glowing Avalanche-- A superheated mass of incandescent ash, blocks, dust, and
        other gas-rich material which bursts from an erupting vent and rushes
        down a mountainside at high speed.  Although most of the material
        hurtles across the ground surface, great clouds of turbulent ash
        often rise thousands of feet above it.   There have been large glowing
        avalanches from Shastina, Mazama, Glacier Peak and Mount Saint Helens
        during post-glacial time.
Glowing Cloud-- The turbulent mass of gas and dirt that rises high above a
        glowing avalanche.  It is also known as "nuee ardente."
Holocene Epoch-- the 10,000 to 12,000 year-long period of time which has
        elapsed since the end of the Pleistocene Epoch (Ice Age).  It is the
        geologic period in which we now live.
Hot Avalanche-- A glowing avalanche.
Horizontal Blast-- An explosive eruption in which the resultant cloud of
        ash and other material moves laterally rather than upward.  Lassen
        Peak's famous "Hot Blast" of 1915 was such an eruption.
Hydrothermally Altered Rock-- Rock that has been decomposed or otherwise
        chemically changed by prolonged action of hot steam and/or acidic
        solutions.  Such rock is often decayed into soft opal or clay, making
        it extremely susceptible to erosion or sliding.  It is thought that
        the former summit of MT. RAINIER was thus decomposed before it slid
        off to form the Osceola Mudflow.
Hypersthene-- A mineral found in basic rocks, or in intermediate rocks such
        as andesite.
Ignimbrite-- Rock consisting of glassy (vitric) ash, usually produced by hot
        ash flows.
Incandescent Ash Flows-- An intensely hot, gas-charged glow of pyroclastic
        material.
Intrusive Rock-- Volcanic rock, which, when molten, was intruded into
        preexisting rocks without ever reaching the surface as lava.  Dikes
        and volcanic plugs are good examples.
Lapilli-- Literally "little stones"--round to angular rock fragments
        measuring 1/10th inch to 2.5 inches diameter, which may either be
        ejected in a molten or solid state.
Lahar-- The Indonesian term for a mudflow originating on the slopes of a
        volcano.
Lava--  Magma which has reached the surface of the earth through a volcanic
        eruption.  The term is most commonly applied to streams of molten rock
        which flow from a crater or a fissure.  It also refers to cooled and
        solidified masses of rock.
Lava Tree Mold-- The hollow impression left when a tree has been engulfed
        by a lava flow.  As the tree is carbonized by the heat from the
        surrounding rock, water escaping the trunk cools a thin crust of lava
        which hardens around the tree trunk.  As the tree decays or
        crumbles into ash, the solidifying lava forms a mold in the exact
        shape of the tree.  See Tree Wells.
Lava Tubes--  Caves or tubes formed by lava inside a lava flow.  Although
        there are several means by which lava tubes can be created, the
        most common explanation is that the liquid interior of a lava stream
        continues to flow after the top and sides have cooled and hardened.
        The center of the flow then drains away, leaving behind a hollow tube.
        The solidified crust of the flow forms the sides and roof of the
        tunnel.
Magma-- Molten rock confined beneath the surface of the earth.  When erupted to
        the surface, it is called lava.
Magma Chamber-- The underground supply house of volcanoes.  These are
        envisioned as subterranean cavities containing the gas-rich liquid
        magma which feeds volcanoes.
Microearthquakes-- Extremely small tremors which are perceptible only to
        very sensitive scientific devices.  Seismographs especially designed
        to detect these microearthquakes are placed near active or dormant
        volcanoes to determine the frequency of shocks in and adjacent to
        the volcano's subterranean magma chamber.  An increase in seismic
        activity can be the first indication of an impending eruption.
        Seismologists at the University of Washington now run a Volcano Watch
        on MOUNT RAINIER and record and measure these tiny quakes on a daily
        basis.
Nuee Ardente-- The French term for a turbulent cloud of hot ash or dust
        which rises above the front and sides of a glowing avalanche.
Obsidian-- A dense, black, glossy volcanic rock almost devoid of bubbles
        or mineral crystals.  It is a highly silicic form of rhyolite.
        Large obsidian flows have emerged in recent past from the Newberry
        Caldera and the flanks of the South Sister.
Pahoehoe-- Hawaiian word for congealed lava which is characterized by a smooth
        ropy or billowy surface.  It is contrasted to aa, which has a rough
        slaggy crust.  Pahoehoe flows often contain lava tubes or caves
        such as those near Mount Saint Helens.
Parasitic Cone-- A (typically small) secondary cone built on the flanks of a
        larger volcano.  It is parasitic because it taps the magma chamber
        of the older volcano, thus using material that would have otherwise
        been ejected by the main cone.  Shastina, on the west side of Mount
        Shasta, is the largest parasitic cone in the Cascades.
Paroxysm-- A violently explosive eruption of unusual magnitude.
Palean Eruption-- Eruption which follows the pattern of the 1902 outburst
        of Mount Pelee, Martinique.  The volcano produced glowing avalanches
        and clouds which utterly destroyed the city of St. Pierre and killed
        at least 28,000 unfortunate people.
Phreatic Eruption-- Violent steam explosion that produces little or no new
        lava.  It characteristically blows out solid fragments of the pre-
        existing rock of the volcanic cone.
Pliocene Epoch-- Period of geologic time immediately preceding the Pleistocene
        and lasting from about 7,000,000 to 2 or 3,000,000 years before the
        present.  During this epoch, numerous shield volcanoes and basaltic
        cones were built in the Cascades.
Pleistocene Epoch-- Period of geologic time immediately preceding the
        Holocene Epoch and lasting from 2 or 3,000,000 to 10,000 years before
        the present.  It was characterized by repeated development of ice caps
        and valley glaciers in the Cascade Range, and hence is popularly known
        as the "Ice Age."  Most of the large stratovolcanoes in the Washington
        Cascades were erected during this period.
Plug--  Solidified lava that fills the conduit or "throat" of a volcano.
        It is usually more resistant to erosion than the material making
        up the surrounding cone and may remain standing as a solitary
        pinnacle when the rest of the original structure has been eroded
        away.  The pointed spires of Mt. Thielsen and Washington are good
        examples of volcanic plugs exposed by erosion.
Plug Dome-- The steep-sided rounded mound formed when viscous lava wells up
        into a crater and is too stiff to flow away.  It piles up as a dome-
        shaped mass, often completely filling and burying the vent from which
        it emerged.  Lassen Peak is the largest and best-known plug dome
        in the Cascade mountain range.
Pumice-- Solidified form of rock-glass which was highly charged with gas
        when blown from the crater.  Usually light-colored, it is full of tiny
        bubbles or vesicles, which makes it bouyant.
Pyroclastics-- The Greek word for "fire broken," referring to fragmented
        volcanic rock thrown out during an eruption.  Another Greek word
        for this kind of ejected material is tephra, which applies to al
        material blown out through the air.
Pyroclastic Flow-- A volcanic flow of hot gas and fragmented material
        (pyroclastics); it may be composed of either pumice or lithic (non-
        vesicular) debris, or a mixture of both.
Quaternary-- The geologic time period that includes both the Pleistocene
        and Holocene Epoch.  It began a maximum of three million years ago.
Rhyolite-- Lava rock extremely rich in silica and with a high glass content.
        Because they are still and pasty when erupted, rhyolite lavas do not
        normally flow far from their source.
Scoria-- Glassy fragments of dark-colored rock, often the product of sprays of
        semiliquid lava shot into the air from explosions accompanying a
        lava flow.  Scoria range in size from 1/10th to 2.5 inches.
Seismograph-- Instrument which detects and records earthquakes, including those
        too weak to be felt by most people.
Shield Volcano-- A broad, very gently sloping volcano built almost exclusively
        of lava flows.  Named for their supposed resemblance to a warrior's
        shield laid flat with the curved side upward, these volcanoes
        are characterized by quiet effusive eruptions with little or no
        explosive action.
Silicic Lava-- Lava rich in silica (over 65%) and having a relatively low
        melting point (850 degrees Centigrade).  It usually emerges as a stiff
        viscous mass and does not flow long distances.  Silicic lavas may
        congeal near the erupting vent to form steep-sided domes, such as
        Lassen Peak and Chaos Crags.  Rhyolite, dacite and obsidian and typical
        silicic lavas.
Solfatara-- Term derived from the Solfatara volcano in Italy which is
        characterized by the quiet emission of sulpherous gases.  A form of
        fumarolic activity, the solfatara can hydrothermically alter the
        chemical composition of the rocks surrounding the vents.
Stratovolcano-- A volcano composed of both lava flows and fragmental
        (pyroclastic) material.  A cross-section through a stratovolcano
        reveals alternating layers (strata) of lava, ash, breccias, etc.  It is
        also called a composite volcano.
Tephra-- Term used by Aristotle to describe air-borne pyroclastic material
        ejected from a volcano.
Tree-Mold-- A hole in a lava flow, created by lava forming the hollow
        impression of a tree trunk.  See Lava Tree Mold.
Tree-Well-- The cylindrical hole in a lava flow created by lava forming the
        hollow impression of a tree trunk, which has been engulfed in the flow.
Tuff--  Rock formed of pyroclastic material; it usually refers to ash-sized
        and perhaps other material; if coarser, it may be called a lapilli
        tuff.  See Welded Tuff.
Vent--  Opening in the surface of the earth through which volcanic material
        is ejected.
Vulcan-- Mr. Spock (just kidding :) Roman God of fire and the forge, after whom
        volcanoes are named.  Also, the planet that Mr. Spock is from.
Vulcanian Eruption-- A type of eruption characterized by violent explosions
        which send dark cauliflower clouds of ash into the air.  Vulcanian
        explosions are thought to be previously trapped gas suddenly breaking
        through congealed rock in a vent.
Vitric-- Term describing volcanic material consisting chiefly of glassy
        matter such as vitric ash which is at least 75% glass.
Welded Tuff-- Rock composed of fine-grained material which was hot enough
        when emplaced to weld or fuse together.







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    ۲۲  Kitsap County's Finest  ۲  
     ۲۲                          ۲
    ۲۲ No ALIAS names permitted ۲   
    ۲۲The NASA MLP is NOT a game۲
     ۲۲ and GIF forum, but is an ۲    
     ۲۲ exceptional  educational ۲   
    platform,  hailed by the 
       local  news media!    
 
 



               VOLCANO

I don't know
I don't know
I don't know where I'm a'gonna go
When the volcano blows.

The ground she's movin' under me
Tidal waves out on the sea
Sulphur smoke up in the sky
Pretty soon we'll learn to fly.

I don't know
I don't know
I don't know where I'm a'gonna go
When the volcano blows.

Now my girl quickly says to me,
"Man, you gotta watch your feet
Lava come down soft and hot
You better love me now or love me not."

I don't know
I don't know
I don't know where I'm a'gonna go
When the volcano blows.

No time to count what I'm worth
Cuz I just left the planet earth
Where I go I'll hope there's rum
Not to worry, monsoon come.

I don't know
I don't know
I don't know where I'm a'gonna go
When the volcano blows.

I don't want to land in New York City
I don't want to land in Mexico
I don't want to land on Three Mile Island
I don't want to see my skin aglow.
I don't want to land in Comanche skywatch
I don't want to land in Nashville Tennesse
I don't want to land in a San Juan airport
Or in Yukon territory.
I don't want to land in San Diego
I don't want to land in a buzzard's bay
I don't want to land on no Ayatollah--
I got nothin' else to say.

I don't know
I don't know
I don't know where I'm a'gonna go
When the volcano blows.



Jim Coleman
Sysop, The NASA MLP BBS of Port Orchard, WA
1-206-871-3965
Many many heartfelt thanks to ALL the NASA MLP
callers, for their support of science. Thanks to
Ron Wright for the encouragement and maps, Sam
McKernan for the help with the park information,
Stephen L. Harris for his comprehensive books
and information on Mount Rainier, and Dr. Samuel
Anderson, of the United States Geological Survey
for spending many afternoons over here in planning
and discussion.  Thanks to all!
September 25, 1993
