In December 1996 shortly after Christmas Day something violent
happened here.
December 1996 before Christmas saw an unusually heavy snowfall.
This area was so beautiful with the mature Pine and Cedar trees
covered in a blanket of white, a peaceful stillness beguiling the
potential danger. Then after Christmas the rain came.
Nicknamed a “Pineapple Express”, warm tropical rains
came in from the south west saturating the peaceful snowy ridge ¼
of a mile above where you are standing. Suddenly the silence was
broken and the landscape was quickly and suddenly changed. Vast
amounts of ice and snow were melted and the already saturated ridge
gave way. If the heat source had been volcanic the resultant slurry
of mud, silt, rock, plants, and animal would have been named a
Lahar. Even without the name the effect was devastating. Had you
been standing on Highway 4 you would have heard a loud sound like a
train approaching as the the ridge above you started to give way
and slide. You would not have survived.
While at school or watching a Discovery Channel program, you may
have heard about fossils that were created by silt covering an
animal or a plant and later after perhaps millions of years they
are excavated and studied. Some specific conditions have to occur
to create a fossil. Typically an animal or plant must be buried in
layers of ash or mud; the layers must be deep enough to prevent
scavenging of the remains and often dense enough to prevent
significant decomposition due to bacteriological action. Even with
these conditions met geological events must provide additional
material over the potential fossil to continue to compress it and
its surrounding silt until the silt itself begins to harden into
sandstone like rock. Water then carries minerals through the
sandstone and slowly replaces the animal or plant tissue. These
mineral deposits are harder and as the surrounding sandstone is
later weathered away the fossils are exposed. Without these
sedimentary processes Paleontology would not be a viable
science.
But wait a minute. This is all well and good but where does all
this silt come from? What processes can deposit enough material to
start the fossilization process? Most people will immediately say
“volcanoes” as portrayed in countless films, and they
would be correct, but there is another cause. This cause is what
you can see the remnant of here.
The landslide that occurred here continued down the side of this
ridge all the way to the Stanislaus River in the canyon below. It
gained strength as if flowed another ½ mile down hill collecting
snow, rain, rocks, boulders, animals and plants. Once it reached
the River bead it destroyed a bridge, the debris of which can still
be seen there, and the Sour Grass Campground that was being
re-constructed at the time. Many pieces of heavy equipment were at
the campground awaiting the end of the holidays to return to work.
A back hoe was washed downstream and has never been located,
buried, it is awaiting its fate, and perhaps it will become a
fossil.
Back up the roadway where you are standing a granite bolder the
size of an 1950s Buick was left on the roadway. The bolder was too
large to carry away and had to be broken up with the remnants
spread into the culverts along the roadway. They remain visible
there today. Oddly enough, even with all that debris churning
across the Highway 4 roadway, there was little to no damage to the
road itself which was re-opened as soon as it was cleared.
To get credit for this cache send an e-mail through my geocache
profile with the first line containing " GC2FACY What happened here
was not an Avalanche! " and the answers to the following
questions:
1) What evidence still remains of this event?
2) Use your GPS to mark one edge of the event area and walk
along the road (be careful) to the other side of the event area and
read the distance you are from the marked point. How wide is this
area at the Highway 4 roadside?
3) Optional: Post a picture with you and your GPS at the event
location.
Do not include your answers in your log or I will have to delete
your entry. If you do not e-mail me the answers to the above
questions your log will be deleted.
I hope you enjoy this Earthcache, for more information about the
Earthcache program visit www.earthcache.org
| I am a proud |
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Contrats to the team of troll # 5 and DesertDon749 who get the
co-FTF recognition!