Thoreau's Legacy: American Stories about Global Warming

A new email from the Union of Concerned Scientists just popped up in my mail box. They are teaming with penguin books and creating an online anthology of stories (in the vein of Thoreau and Carson) about our current environmental problem-global warming. If you haven't heard of the Union of Concerned Scientists, they seem to be spending all of their time right now trying to show how the current folks in Washington haven't been using the most current scientific thought to make decisions. They also just had a great editorial cartoon contest and are suing the winners to create a calendar for next year. I actually gave a few calendars as gifts last Christmas. The topics are so sad they are funny. Check it out here. They have a thought provoking web site.

Below the Wingate

Today I had the chance to be in my favorite part of the Colorado Plateau. It's not a specific place but rather a place in time. In many places throughout the canyon country of Western Colorado and eastern Utah, there is a cliff-forming formation called the Wingate Sandstone. It seems in Triassic times, this area was quite the sandy desert, reminiscent of the Sahara desert of modern times. This wind blown sand accumulated a few hundred feet of depth before the next major climatic change came in to produce the Kayenta Formation, a great caprock keeping the Wingate from blowing away...again.

These reddish cliffs make a heck of a barrier when trying to cross the area and there are only select places where you can safely make your way through the cliffs.

But.

The cliffs themselves are the greatest red color and show remarkable cross bedding indicating their origins as sand dunes. Today the desert varnish colors the walls with stripes of black making amazing works of art. I just wish my camera would do justice to what I really see.

As I get older, desert hiking is quickly replacing my mountain adventures as what I do for entertainment. I enjoy walking through the canyons and dissecting their geologic history. I can look at the cross bedding and conchoidal fractures way up on the wall and I can understand how the sand grains were moved by wind those long eons ago... but, when I reach the bottom of the Wingate and start walking through the Chinle, I also just get mesmerized by the beauty in the rocks. So, when you get a chance, spend some time, even a night below the Wingate and you will see what I mean.

Sand bar camping

As the last post explains, we had plenty of sand bar camping and only small amounts of Teva sucking mud on our Geology of the Green River class. The flow of the river had dropped to its not-runoff-minimum just the week before and we were expecting to see lots of stagnant mosquito filled back water eddies behind the best camping sand bars... but no. The camping was awesome.

It was interesting to look for changes in sand bar location and size after a banner snow year across the west. The Green River, although dam controlled, still boasted a larger than normal spring discharge that we hoped would translate into lots of sand transport, at least from the channel centers to the river's edge. The upper stretches of the river (between Green River UT and the start of Labyrinth Canyon proper) saw just that, a healthy crop of not new, but certainly beefier sand bars than the year before. However, once we were in the narrower portions of the canyon, the sand bars were certainly just as numerous as other years but also all showed evidence of terrain loss. The focus on the class did not allow any quantitative measurements so this is all anecdotal.

One fun exercise was that we examined the sorting of particles across each sand bar to see how the flow of water changed as the discharge dropped and the sand bar was exposed above water. Mostly however, the class seemed to find a need to memorize each formation name as we floated by and they were less enthralled with studying the energy regime that created the rock they are looking at.

SAND!

Just back from the Green River (Labyrinth Canyon). Discharge was about 3100 cfs and the sand bar camping was amazing. The Teva sucking mud was at a minimum.

I'll tell more when I catch up on sleep.

Mud or Sand?

I am in the midst of getting my Geology of the Green River class finalized. You always have to wait until the last minute to see what the water conditions are like. The past few years have seen lower than average water conditions. The good news is that the sand bars are numerous and camping is pretty easy...the bad news is that you paddle all day every day. This year could be different with the record snow pack last winter. Rivers have been running high but it looks like the discharge has been dropping off rapidly in the past week as the snow pack from last winter has about finished melting. This graph shows a 1000 cfs drop in discharge about every 60 hours. Of course this is a dam regulated river flow and we know we won't run out of water (which this graph might suggest) , the question is when will the river reach its regulated base flow of 1975 cfs?
If we have water levels greater than 3000 cfs, there might be a bit of mud to content with, in which case the class might spend even more time looking at modern day sediment and sediment transport down the river and on our sandals. If the water levels drop to closer to 2000 cfs, we will have more sand and more sand bars to play with.

A Long Bike Ride

I am back home after riding the 185 mile C&O canal towpath along the Potomac River from Cumberland MD to Washington DC. The canal was a busy place for almost 100 years before the railroads took over the job of transporting stuff between the coast and the interior. Now protected by the National Park Service, this very long and very skinny unit of our National Park System provides an incredible chance to ride a bicycle through the heart of the Appalachian Mountains while not climbing a single hill...pretty cool.

I have to thank Callen for giving me some advanced information to help me appreciate the geology of the area. I am afraid I have that Western bias that assumes geology should be right in front of your nose with little vegetation hiding the nuances.

Now I am off to Lake City where we will attempt some easy 14'ers, and then one more geology class to teach while floating from Green River Utah to Mineral Bottom, 65 miles away.

I love summer!

summer fun

Last week I spent some time in the field with a group of elementary teachers looking at the geology of the Uncompaghre Plateau, specifically along Dominguez Creek and the Gunnison River. The week started at the Colorado School of Mines campus in Golden where we re-acquainted ourselves with simple geologic processes and then these lessons where put to the test in a 3 day field trip.

My big push has always been to try to understand the environment where the rock units we are studying were formed. To get the idea of different energy regimes in stream flows we calculated the discharge of Dominguez Creek near our camp.


To examine the difference in stream velocities we hiked upstream to an area where the creek was had eroded a small channel through much harder Pre-Cambrian Metamorphic rock thus a much smaller stream cross section. Discharge was approximately unchanged but the velocity was much higher. To test our findings we did as any geology class would do...we made a butt dam to see if we could stop the flow of water. We were unsuccessful. The space on the right was left for me and even though I tried I could not fill the gap.


It was a great time where we were able to discuss some local geology as well as how to incorporate more of the earth sciences to elementary classrooms.