Sunday, October 3, 2010

2010 River Trip Day 1 - 9/12 Lee's Ferry to North Camp river mile 20.8

2010 Geology River trip - we will be discussing this Wayne Ranney Grand Canyon river trip with a focus on Geology along with some information on the Canyoneers trip, their guides/stories and more.
I have included a number of Art Manburg, Jeff Eorio and John Zambrano photos in the journals and am very grateful for them.

2010 River Trip dramatis personae

2010 Trip Summary Links to Day 1 2 3 4a 4b 5 6 7 8 9 10
 
Geology is the science that deals with the history of the earth (including volcanism, weather, ocean/lake locations/levels, and the record of life on earth) as seen in rocks.  The Grand Canyon is one of the best places to see, hike and experience Geology.  We will discuss aspects of Geology in these journals.

For more information on Geology and the Grand Canyon I provide a number of links on my web site http://bmerrow.com but also share this NPS link – it is a great basic resource for those interested in more information on Grand Canyon Geology.  And, of course, everyone should have a copy of Wayne's Carving Grand Canyon and Ancient Landscapes – I reference them in various journals.

These journals will be posted to my website when completed – your feedback and corrections are desired and will be incorporated.
The images for our 2010 Grand Canyon trip will be made available at http://flickr.com/bmerrow - you will have access to all resolutions of all photos I took.  Selected photos from a 2009 and a 2008 Sept River Trip are already on Flickr.  The 2010 materials are not yet loaded – I am still processing the data from the trip.

In the below - click on an image to see a larger version.

Lee's Ferry - for more information see this link

Our boat is the Philomena (Canyoneers Boat 2) and is the same boat used on last year's river trip.  We have two of the boatmen/guides from last year as well - Brandon Green and Jamie Townsend.



Lee's Ferry is above the official start of the Grand Canyon - rising above it are 
Mile 0 layers above GC strata - from river up, Moenkopi, Shinarump Conglomerate and other Chinle Formation members, Kayenta, capped by a thick exposure of Navajo Sandstone. Downstream from Lees Ferry, the Kaibab Limestone emerges from the river marking the start of Grand Canyon.  For the Grand Canyon park area all the layers above Kaibab were eroded away and we see only rocks of Kaibab age and older.  


As we pull out from Lee's Ferry we see people fishing - this is one of the last spots where visitors can access the river without a long hike (until we exit Grand Canyon park in 10 days).


Training rock is used by park service and river guides for rescue training

Lee's Ferry was the only way across the river until the Navajo Bridge was built in the 1920s - a steep road was built up the cliff on river left

As we proceed down the river we quickly get to the start of the Grand Canyon where the Kaibab Limestone rises out of the river at the first point on river left

The turbulence in the water is the little Paria Riffle – the Paria River from the north is normally a small creek entering on river right with minimal impact.  But this summer August 4 it flashed and exceeded 2000cfs entering the Grand Canyon.  This would have been interesting to see but a lot less fun to directly experience.  Such sporadic events account for most debris fans in the river and the resulting rapids.  

The Grand Canyon cuts thru the various rock layers but much of what we see rapidly appearing as we proceed south is the result of the river cutting thru rocks raised by a general uplift caused by the Kaibab Monocline.


Soon (around mile 1.7) the Toroweap Formation appears (this forms the layer under the Kaibab) - below a 2010 photo of river left

And here a photo from 2008 of the Toroweap rising on river right

Here is the Coconino as seen at Mile 3.9 - it will be visible for most of the rest of our journey.  Click on the photo to see a larger image where the Coconino cross bedding is very apparent.  


Below is a detail from 2009 showing the cross-bedding

 

Nearing Mile 5 we see Coconino above water level topped by Toroweap and Kaibab - below looking back up river at Navajo Bridge on left we see the top cliff is Kaibab Limestone, the slope under it is Toroweap Formation, and the bottom cliff is Coconino Sandstone.  
These 1st three layers will soon be followed by the rest of our mnemonic for the main Grand Canyon rock strata: Know the Canyon's History, Study Rocks Made By Time.
So far we Know (Kaibab) The (Toroweap) Canyon (Coconino) . . .

10:49 Jeff Eorio photo upriver towards Navajo Bridge (thanks much for including me)





After mile 5 we see the Hermit Shale appear on river left (red at bottom of picture) – this is a slope forming deposit and is the History in our mnemonic.

Here is a photo of a typical Hermit slope

Mile 6 we see our first bighorns - this is another year (like 2009) with more bighorn sightings than I usually see



Heron


Mile 7 I get photos of a heron posing on the bank and standing upright in the detail below)

John Zambrano provides this photo of early bighorns


11:09 reflections in the water were outstanding on this trip - I added a Canon SX20is to my camera bag and it turned out to be especially good at this type of image - we will see a few of these reflection images in journals for later days (I admit I went wild for reflections).

12:42 Ten Mile rock is a large block of Coconino Sandstone that fell from the cliffs above

13:30 around Mile 11.4 the Supai appears


Here is Brown Inscription at Mile 12 in the Supai (from 2008 trip)




13:36 USGS Inscription with geologist hammer image


John Zambrano image of hammer


13:38 Jeff Eorio photo


13:58 After Mile 12.5 the Supai Gorge becomes well defined – we will see a number of different gorges at river level during our trip


below is a detail of the Sheer Wall rapid we saw ahead in the Supai gorge

13:58 Mile 14.5 Tanner Wash enters on river left

13:58 Mile 14.5 Sheer Wall Rapid is formed by Tanner Wash

Mile 16 detail of Esplanade Sandstone in the Supai - this layer forms the Esplanade bench on the north rim down river - potholes are seen in the image below. 
On the north rim, this layer erodes as a flatish surface similar to the slickrock common in Utah.  It easily forms depressions/holes that are a source of water for hikers in the Esplanade. Of course, one cannot count on finding this water but many potholes are large and maintain water for weeks – so recent trip and weather reports can be very useful.



The SX20is camera is a 20x superzoom - this came in handy for a number of later Geology photos.  I tried it out on day 1 on a fly on our boat with the below result:



Mile 20.8 is North Camp - our first camp.  It is located on river right just above rapids which provides background noise to cover up happy river runners snoring.
Because we setup camp early, a hike was done before dinner up North Canyon


at start of hike Wayne points out root casts in river sediment


 
North Canyon - exfoliation in sandstone accounts for the interesting strata below (photo below from 2009 hike). Note how the sandstone spalls parallel to all of the drainages - as the confining pressure is released by the erosion and removal of overlying rock, the sandstone pops out to create these lines of weakness.


John Zambrano next two photos up North Canyon 2010 Sep 12


The North Canyon hike ends at a pool (photo below is from my 2009 trip)


16:28 Jeff Eorio photo of pool

John Zambrano photo of Audrey and Dana in North Canyon at pool 2010

John and Laura Zambrano at pool

16:40 Jeff Eorio photos of exfoliation




Below, some camp scenes:
John Zambrano photo of camp

Butterfly on beach 


Sacred Datura plant (first of many we will see as we go down the canyon)


Moonflower detail (so called because the Sacred Datura flowers open at night).  During our trip we start out with an early moon which increases to full moon by end of trip.


we also spot a dead scorpion (no live ones end up on people on this trip)


my North Canyon campsite - one of the best on this trip - note the shelves and almost flat surface (rock shelves/chair are key priorities for me in selecting camp sites) - added bonus was a cloths drying rack




View of strata across the river from our camp


Our dinner was beef and potatoes (with a vegetarian stir fry for those who preferred).


day one ends with a marvelous sunset (a frontal system moves thru and we have a mostly clear sky and no rain for the entire trip)



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