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Grand Canyon - look closely and you can see the Colorado River
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Our travel from Payson was uneventful, thankfully.The RV park we are staying in is pricier than most we patronize, but it is the nearest to the Grand Canyon so we didn't have much choice. Even from here it was an hour to the canyon. The park is clean and neat (bathrooms
were beautiful but frigid) with lots of extras, but the sites are
stark (nearly no plants or trees) and beware! This park insists that
you pay the entire reservation up front, and if you have to cancel
less than 3 days prior to arrival, they keep all your money.
Additionally, if you have a discount for the park, expect discounted
service. We had a reservation, and after checking in and setting up,
found that the advertised WI-fi didn't work. After an hour plus on
the phone with the tech support, we were informed that the reason we
didn't have WI-fi was because there were some big RV's parked between
the WI-fi antenna and our RV. They offered to give us a different
site, but between being frustrated, calculating the time we spent
trying to get WI-fi to work, putting things away, pulling in the
slides, re-leveling, and setting up again plus not knowing if the
WI-fi would work in the new location, it just didn't seem worth it so
we declined. The signage for check-in office in is also inadequate.
Even the employees here say the two biggest complaints they get are
about the poor WI-fi and poor signage. (Our next stop cost almost
half what this place did per night, the WI-fi worked beautifully,
showers were good, and the park nicely landscaped.)
The annoying problems at the RV park
couldn't ruin the Grand Canyon. It was everything I had read about
and more. Pictures and movies don't do it justice, the history is
fascinating, and the geology left me speechless (well – almost).
The North and South Rims are just 10 miles apart, as the raven flies,
but 215 miles by road. The South Rim elevation averages 7,000 feet
and the summer temperatures range in the 50's – 80's. The North
Rim, at 8,000 feet, is about 10 degrees cooler than the South Rim.
This trip took us to the South Rim – next time, we're hoping to
visiting the North Rim and sometime we'd like to take part of a trail
down into the canyon a short way.
As we have found at all the other
National Parks, the visitor center is a wonderful combination of
educational information, helpful rangers and volunteers, comfort
stations, and a well-stocked gift store.
It's a great place to finish planning
your day – we had a good idea of what to expect and what we wanted
do from the website and the “know before you go” link, but it is
always a good idea to check with a ranger or volunteer to be sure
nothing has changed.
We were both a bit leery of having to
ride the shuttle bus around the area we wanted to visit, but we gave
it a whirl. Our fears were for naught and it was, for the most part,
great. There were a few places we'd like to have been able to stop
and look at, and had we felt like walking the couple of miles to the
next stop we could have done just that. The shuttle buses are timed
so you only have 15 minutes between them, so whether you like to take
a quick look or, as we do, take time to read the signs, talk about
the sights, and get some photos, you won't have long to wait for the
next one to come along.
Rich had visited here 40 or so years
ago, and he has been having a ball just watching my reaction to this
marvelous country. This time, he had me close my eyes as he walked me
up to the first viewing area. The area around the canyon is fairly
flat and rocky, then standing at the railing, opening my eyes and
seeing the huge canyon filled with buttes, pinnacles, and cliffs was
awesome in the purest sense of that overused word.
We spent seven hours at the South Rim
and could easily have spent another day or two. In addition to the
fantastic canyon and its formations, we saw a young mule deer, its
ears turning one way and canyon filled with buttes and another until
they looked like helicopter rotors and several elk. Just outside the
park we caught sight of seven pronghorns. The Canyon is overwhelming
in size and beauty and I think we will enjoy it even more the next
time, since we've had time to digest some of the things we've learned
about it. One thousand million years ago. Geez!
The sights just keep getting more and
more beautiful the farther west we travel. Can't wait to see what's
next!
The day we left, Williams was expecting
snow – we were happy to be heading away from it up to up to Las
Vegas and the Hoover Dam.
The
rest of the this post (after the photos below) is an overview of the geologic growth of the
Grand Canyon, which I took from a pamphlet at the visitor center.
Feel free to skip it if you're not interested.
The
lowest layer of rocks we see is called the Vishnu Basement Rocks –
huge burly dark reddish-black rocks and they date back between 1,840
– 1,680 MYA million years ago. One thousand million years – I
can't even begin to get my feeble brain around that number. These
Vishnu Basement Rocks were formed nearly two billion years ago when
two tectonic plates collided. The heat and pressure from this
collision changed the existing rocks into a dark metamorphic rock –
the basement of the canyon. There are lighter colors mixed in with
the dark and were formed when molten rock squeezed into cracks and
hardened as light bands of granite.
Next
we see what is called the Grand Canyon Supergroup which is dated
around 1,200-740 MYA – its color is also dark reddish-black, but
the rock appears different in texture and the manner in which it is
eroding. That's because this layer is red shale, fossil-bearing
limestone, and dark lava, but it can be seen in only a few areas of
the canyon. The many strata of the Supergrouop accumulated in basins
formed as the land mass pulled apart. The expansion caused huge
blocks of the Vishnu to tilt, inclining the Supergroup layers. The
same process caused Nevada’s alternating basin and mountain ranges.
(Cedar Breaks and the area around it is a good example of this. It is
coming up several blogs after this one.)
The
Layered Paleozoic Rocks come next. These rocks are made up of a
number of different different layers that were formed from 525 - 270
MYA, and are composed primarily of sedimentary rocks and make up the
upper two-thirds of the Canyon's walls. These rocks formed at the
edge of the continent, near sea level, the remains of sea life
accumulated on the ocean floor to form limestone. Rivers deposited
the sediments in swamps and deltas that then became mudstones, and
eventually solidified into sandstone. Some of the different layers in
this group are repeated in the area in the names of mountain ranges
and National Forests -Tonto, Coconino, Kaibab to name the ones I'm
familiar with.
About
70 MYA the Rocky Mountains began to form, pushed up as the North
American Plate overrode the Pacific plate. As a result, a large
section of what is now eastern Utah, northern Arizona, western
Colorado, and a corner of New Mexico rose up from sea level
elevations to thousands of feet, forming the Colorado Plateau. This
uplift occurred with remarkably little tilting or deformation of the
sedimentary layers.
The
stage was set for the carving of the Grand Canyon.
By
five to six MYA the Colorado River flowed across the Colorado Plateau
on its way from the Rocky Mountains to the Gulf of California Each
rain washed sparsely vegetated desert soils into the river. A steep
gradient and heavy sediment loads created a powerful tool for
erosion. The river's volume varied seasonally and over time. As the
last Ice Age ended 12,000 years ago, the flow may have been ten times
today's volume.
As
the river cuts down, the canyon deepens. Tributaries erode into the
canyon's sides, increasing its width. Erosion carves faster into the
softer rock layers, undermining harder layers above. With no
foundation, these layers collapse, forming the cliffs and slopes
profile of the canyon. Erosion wears away the ridges separating
adjacent side canyons, leaving buttes and pinnacles. The age of the
Earth is 4,500 million years.
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