Durango Bill's
Grand Canyon 3-D Tour
Boucher Creek to Crystal Rapid
to Ruby Canyon
Grand Canyon Miles 96 to 104
This
view to the northwest has Boucher Creek in the lower left
corner with a remote section of the South Rim stretching out
toward Havasupai Point in the distance. The North Rim at
Point Sublime can be seen in the upper right corner.
Slate Fault cuts left to right across the
center of the picture. Of major interest to both rafters and
geologists is Crystal Creek, which has developed along the
fault. Crystal Canyon enters from the right edge and forms
Crystal Rapid where it joins the Colorado River. Scorpion
Ridge can be seen directly above the junction.
Prior to December 1966 there wasn't much more
than a riffle at the base of Crystal Creek. Then a six-inch
rainfall generated multiple debris flows that included
18-inch diameter Ponderosa Pine Tree logs that were carried
at least 8 miles down from the North Rim. The resulting
debris fan created Crystal Rapid. Robert Webb and Peter
Griffiths have documented 168 tributaries to the Colorado
River in the Grand Canyon that have had debris flows in
modern history, but Crystal is the most dramatic. (More on
recent debris flows when we get down to Lava Falls at mile
179)
There is always an argument as to whether
Crystal or Lava Falls is the wildest rapid on the river, but
historically, if you are going to have a problem on the
river, Crystal is the most likely place. Page 376 "Grand
Canyon Geology" by Beus and Morales has a photograph of a
large motorized raft being completely swallowed by a
standing wave in excess of "5 - 6 m." (16.5 to 20 ft.)
at Crystal Rapid. On occasion, rafting trips have celebrated
surviving Crystal Rapid with an "ABC Party" (Alive Below
Crystal).
View to the
north-northwest with Scorpion Ridge in the center and the
South Rim's Havasupai Point in the distance. Ruby Canyon
enters from the left edge and joins the Colorado where the
river bends slightly to the left before straightening out. The
North Rim’s Point Sublime is again visible at the right edge.
The Crazy Jug Monocline/Fault has contributed to
Tuna Canyon, which starts right of center and extends toward
the top edge. The inner gorge is still composed of 1.7 billion
year old basement rock although somewhat different than the
Vishnu/Brahma Schists. The resistant Tapeats Sandstone forms
the flattish shelf with the usual Paleozoic sequence above.
Return
to
river
miles 88 to 96
Continue
to river miles 104 to 112
Return
to
the Index Page for the Grand Canyon Tour
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