Monday, December 22, 2008

Desert Rat or Mountain Climber

This has been a gray snowy week. The pass has over 5 feet of snow now sitting on the ground and the avalanche danger is high. So...I am posting an image from my most recent trip into the Canyonlands. I have had a number of friends over the years leave the mountains to become full time desert rats. I am moving that way myself. My youth was spent climbing all over Colorado, a little higher than John Denver campsite. The alpine tundra was the place to be. My graduate work was studying the glacial history of The Colorado Rockies.

Now, I crave the desert. I am enjoying my transition from mountaineer to desert rat.

The image above is looking east from deep in the canyons. The rock is the Cedar Mesa Sandstone...Permian in age. The red layers come from sediment sloughing off the Uncompaghre Uplift in Western Colorado, the white layers come from Sahara like sand dunes to the north. The mountains in the distance are the La Sal Mountains, a laccolith just outside of Moab and in the foreground is one of the six shooter peaks, a column of Wingate favorite formation in the canyons.

It's dumping up on the pass. I really need to go skiing

Hope everyone has a great Christmas.

Tuesday, December 9, 2008

It's gone

Last weekend I was in Moab Utah and took a fun hike along the "primitive" trail in Arches NP. The trail passes by some of the worlds greatest rock spans. Landscape Arch, the longest span in the world looks like it could collapse at any moment, but it was Wall Arch that actually fell last summer. I walked up to a pile of rubble and looked around to see where it had fallen from...well...the arch is gone!

And as everyone knows: Geology Happens.

Thursday, December 4, 2008

Green River field work

For this month's Accretionary Wedge: favorite places to do field work:
I will be the first to admit I don't do real field work. I usually even leave my Brunton at home (but I usually have my GPS) I have been involved in K-12 education as well as introductory college level teaching for almost 25 years. I love the teaching...I can do with out the administrivia. My favorite class I have been teaching is the Geology of the Green River by Canoe through the Colorado School of Mines. Its nothing more than a "teacher enhancement" course meaning that the credit is only good for re-certification of the state teacher license. That said...we do some fun science on the river. The first image shows the river coming around BowKnot Bend. This entrenched meander takes 7 river miles to go less than 1/2 mile of a straight line. For Earth Science teachers who have taught river meanders, oxbow lakes and simple river mechanics in a classroom, the real thing helps them immensely in the next school year.

This image is Anvil or Inkwell or Dellenbaugh Butte. The natives called it the first two names but Major Powell changed all that. What a fantastic example of advance and retreat of seas through out the Summerville Formation. It is an especially great teaching tool when you can see how silty the river is and then examine the grain size of the easily climbed strata. last year I had a student climb to the top for a sample. he was disappointed when I explained the top most sandstone cap is actually a member of the Morrison. Oh well, you can't fault his effort.

As anyone who has read any of my posts knows that my favorite Canyonlands formation is the Wingate with it's cap, the Kayenta. It is a great example of windblown to marine-ish environments. The desert varnish is awesome and the cross bedding is plain to see. Again, many classroom teachers have taught the principle, but this gets it in their face.

This view come near the end of the class. You can clearly see how the Wingate creates pillars when the cap rock is taken away. Underneath the Wingate is the Chinle formation and we have fun exploring some of the Uranium mines in the area. The BLM has just recently closed most of them so we really just loiter outside looking for petrified wood and seeing how the miners did their thing back in the 1950's.

This is the entrance to the Hey Joe Uranium mine. The entrance is closed now, but a few years ago it was open for all river rats to explore a cool (literally) mine with walls littered with petrified wood.

It is a great experience to be able to take teachers down through this stretch of the Green River and explore the walls of the canyons as we float along in the August heat!

Tuesday, December 2, 2008

2 months in

We are 2 months into the new water year and things are looking OK on Red Mountain Pass, the closest snotel site to my favorite play areas. We are just a little below average right now but the best is yet to come. That storm last weekend really helped put moisture on the ground.

I'll keep you posted.

Tuesday, November 25, 2008

Confluence of the Green and Colorado Rivers

Early in Thanksgiving week we were able to visit an iconic location of the American West, the confluence of the Green (left) and Colorado (right) Rivers. There has been so much written about these rivers and so much western history has happened between the two rivers that a visit here is really mandatory for any devotee of the area.

You can clearly see the Green River with a large dose of suspended solids coming into the main stem of the Colorado looking just like a lateral moraine between two converging alpine glaciers. It is interesting to watch the dividing line between the two rivers slowly dissipate as you travel down stream. Any trace of this division will be obliterated in about four miles when the rivers passes through the upper most rapid in Cataract Canyon, Brown Betty.

Last year, I had the opportunity to fly over the confluence and experience the "google earth" view. You can see the silty Green River water staying remarkably separate from the Colorado for quite a ways further than this year's experience. The biggest reason was last year's discharge was approximately 800 cfs and this year it was flowing at over 2400 cfs.

Friday, November 21, 2008

Decorative rock and the Cutler formation

My next door neighbor, a retired local rancher invited me over to check out his new boulder. His ranch is in the valley below a great outcrop of Cutler and he decided that this conglomerate needed to be in his retirement from yard. His real reason for inviting me over was to give a quick historical geology lesson about the origins of his boulder.

The Cutler, at least here in Western Colorado is a rough conglomerate filled with the practically unsorted material that eroded off of the Ancestral Rockies...or at least here the Ancestral Uncompahgre Plateau. If my photo taking skills were better, you would be able to see largish cobbles (I did remember to add a nickle for scale) of all sorts showing the type of rocks that made the highlands of the Pennsylvanian. We discussed how you could break off a larger cobble and hold in your hand a chunk of rock from an ancient mountain range. He was impressed that he took the boulder from the location that gives its name to the formation. Cutler Creek.

Coupled with the Fountain formation, Minturn formation and the Maroon formation (all contemporaries, all red beds and all conglomerates) we see the outlines of the Ancestral Rockies during the Pennsylvania and Permian periods. This has been a great exercise with my students in trying to determine the extent of this ancient mountain range from data easily dug up today. They can visualize the high energy environment that mimics what we see in the mountains today creating these alluvial fans of conglomerate.

Wednesday, November 19, 2008

Teaching Science to Kids

Way back in my undergraduate days I had the chance to either do the industry thing (in geology that often means oil fields) or go into education. I chose geology education, especially in the K-12 arena. I guess this explains why I didn't get the memo about the demise of the Tertiary...but I digress.

There have been lots of great and not so great programs that have crossed into my classroom. I was a charter member in the Colorado River watch project where we studied the geology-chemistry-physics of rivers to determine overall stream health (biology). The image here is a group of teachers learning how to calculate discharge.

I spent a week at the Colorado School of Mines campus learning how to operate state of the art seismographs to be placed at local schools (that one was shot down by a building principal).

I could go on about the GLOBE program, project wild, wet, damp and all of the others. All very good programs that have stood the test of time. I have just been introduced to another program. This one aimed at middle school kids. (Research tells us that many kids choose the scientist track as 8th graders. )

The JASON project has been around for awhile, but its newest iteration as a subsidiary of National Geographic is one of the best mechanisms to get kids excited about science that I have seen for awhile. The idea is to use new cutting edge ideas AND their researchers to grab the kids. Yes, they start by focusing on the sexy stuff, (flying into hurricanes and swimming with sharks) but they end by hitting all of the key concepts in that discipline as well as doing some good middle school science and in an affordable way. It's not just about the activities they do with the kids but the concepts are backed up by the traditional print text books (think National Geographic for kids)and an impressive array of resources on their web site. Yes, finally a public school curriculum that uses the power of the Internet!

Lets continue to support teachers getting kids excited about science.

Tuesday, November 11, 2008

wild animals in the field

Things have been really busy this past month...but I couldn't help but want to post my little part of the animal meme.

Its funny with all the time I spend in my outdoor lab, there are few animals that I have seen and even fewer that have been out at the same time the camera was out.

The turtles on the C&O canal were fun to watch. I live in the arid west and am not used to such aquatic species.

I have already posted this picture when we saw the baby lambs learning rock climbing skills near the Gunnison River.

Of course there is lots of evidence of animals in the distant past.

and the high altitude mountain goats.

Thursday, October 16, 2008

No Child Left Inside: 4th Graders in the Red Mountain Mining District

Last week I took a group of 4th Graders from a nearby elementary school to the old ghost town (I guess there aren't any new ones) of Ironton Colorado. This area is smack in the middle of the Red Mountain Mining District and has quite a few nearby mines to examine. Here we are standing on the tailings from the Larson Brothers mine. The mining district is pretty much right on the rim of the Silverton caldera, with the ore deposits all being associated with breccia pipes and the ring fault system at the rim of the caldera. Walking around the district you can see the remnants of the breccia pipes with small mines (and the occasional large one) at each base.

The kids were quite interested in the color of the water coming out of the mine and even though the chemistry was a bit over their heads, they got the idea that the pyrite oxidised into a strong acid. Then they all jumped over the stream so that the acid water wouldn't dissolve their shoes.

From here, we walked up valley into the town itself and then visited the renovated Colorado Boy headframe. The Colorado Historical Society has done an awesome job restoring the structure which I have shown to my college and high school classes on our field trips here. There is not much written about what was mined here beyond the usual, copper, silver and galena ores. It is also a great place to take a rest during a mid winter ski. This picture nor the next was of course not taken last week

Above the Colorado Boy is the remnants of an old wooden flume that transported a tailings slurry to the massive tailings pile in the valley bottom. The image here is the old suspension structure carrying the pipline across Corkscrew Gulch. Legend around here suggests that when this was made, it was the 2nd largest suspension bridge in Colorado. They engineered the pipeline so that it bowed upwards when there was no load and then during slurry operations it would assume the correct downward slant. Please don't cross the bridge now!

Tuesday, October 7, 2008

geologic time and the budget- An analogy of sorts


I was thinking about asking the Department of the Treasury for some help this semester in explaining exactly what 4.5 billion years looks like. They seem to have no problems with really large numbers. Here is a link to a story about the national debt clock being out of room.

Perhaps scientific notation will help? How many significant digits do you want?

Monday, October 6, 2008

Black Rocks

Last weekend was spent on a stretch of the Colorado River through Ruby and Horse thief Canyons. It was an awesome early fall day with warm daytime temperatures and the leaves just starting to turn.

Here, our flotilla is approaching the Black Rocks Monocline. Black rocks is the local name for...well, an outcrop of black rocks where this stretch of river sees its only rapid. I am not sure but it seems as if the Laramide left us more than our fair share of monoclines on the Colorado Plateau. My field work is very limited, but we seem to have a bunch. Anyway. The monocline shows a great bend in the Wingate-Kayenta-Chinle combination, much different from the usual flat lying cliffs we are used to seeing. Around the river bend will be the Black Rocks. These pre-Cambrian rocks are much harder than the Mesozoic sediments found everywhere else. The river channel in this section is much narrower, but deeper and the whole flow must squeeze through the channel creating a faster current, with some great hydraulics. I have seen whirlpools appear out of now where and just slap a canoe over, capsizing the boat and throwing dinner into the water, not to mention the two paddlers.

These rocks have been dated to 1.7 billion years old and it looks like a migmatic pegmatite with a few quartz veins shooting through (did I think of taking a close We had even camped one canyon up river with a great outcrop of the same material. Oh well, sitting right on top of this early Proterozoic black rock is the Mesozoic Chinle formation which clocks in at about 200 million years old. This trip was for fun, but every early summer I take a few geology-hungry K-12 teachers down this stretch and they love being able to stand on 1.5 billion years of missing Earth history. wow!

Tuesday, September 30, 2008

Happy New Year

Happy New Water Year that is. On October 1st we start the 2009 water year. The graph on the left is the 2008 water year for Red Mountain Pass. It was a good year.

You can see that the snow accumulation started late. October and November were warm and dry. Then on December 1, as if a switch were thrown, the snow started coming down and didn't stop until April, where it then slowed down a bit. The spring was cool with a few storms here and there, but the snow still melted out earlier than the historical average would have predicted.

Now we are getting ready for the new water year, hoping that there will be enough moisture for all. The graph is all ready on the web site, now all we need is snow.

NOAA is predicting southwestern Colorado will have slightly below average moisture in the fall changing to equal chances of normal precipitation in late winter.

Stay tuned and we will see.

Wednesday, September 24, 2008

The Carnival in space- Accretionary Wedge 13

This month, Good Schist ask about our interest in geology off planet. I am cheating somewhat since my post is about a phenomenon that happens here on earth as well as in space. That is the idea of impact craters.

Looking up at the moon the cratered surface is pretty easy to make out even with the naked eye. With a small telescope you can easily see that indeed those shapes up there are little pock marks. Boy, did that observation get Galileo in trouble when he suggested that a heavenly body might just have zits.

We can be reasonably sure that an old surface will have a greater chance of being hit by objects flying in space. the older the surface the greater the density of craters there should be, conversely, new surfaces should be somewhat clean of impacts. Using this idea, I have had many of my high school and undergrad Astronomy students counting craters to determine relative ages of different surfaces. The maria regions having fewer craters indicate a newer surface and the upland regions being just pockmarked with craters indicate an older surface.

Airless bodies, like the moon are pretty straight forward. However, the Earth and any other planets with active weathering are a little harder to study. We want to look not only at the density of craters, but examine how quickly they are obliterated by geology. The Earth then ups the ante with active plate tectonics so that the old craters are not just weathered away, but completely recycled. And then there is Venus. The old debate between catastrophism and uniformitarianism has been getting a work out on that planet. . I won't get into the Venus mystery as hypo-thesis covers it in great detail.

Craters have now been counted all over the solar system, the inner terrestrial planets and the moons of the outer gas giants. It is fun to show students how much information can be gleaned from a bunch of pictures sent back from our robotic explorers.

I think the overall favorite impact crater we ever studied was Herschel on Saturn's moon Mimas. Every student of mine has called this the death star, interesting because the movie was made a few years before we had any imagery from Saturn showing us the moon.

This unit always brings up the idea concerning the chances of a repeat K-T impact on our modern world. Most kids don't believe it could happen again until we pull out the Earth Crossing Asteroid list. But as I often tell them, Geology happens and that includes impacts from space.

Monday, September 22, 2008

meeting geobloggers

Last week I found myself on the Fort Lewis college campus and thought I would try and find fellow geoblogger Kim at All of My Faults are Stress Related. It was great fun to interrupt her work saying my name is Ed but am also known as Geology Happens. We had a fun quick visit, talking about some of our recent posts and then had to go our own respective ways. Kim had a class to teach and I had a mountain to climb.

So Kim, thanks for giving me part of your busy day.

Wednesday, September 10, 2008

5 minerals

I saw the original meme about 50 minerals and thought, well that seemed like too much thinking for me right now. When I saw Callan's 5 mineral challenge, I figured I could put a few brain cells into action.

1. Quartz: When you spend as much time tromping through sand stones as I do then quartz should be high on your personal list. Not to mention that its pretty stable with our current environmental conditions so we find it in so many places.

2. Hematite: less as those great crystal specimens from that favorite 101 lab but more as one of the mineral cements holding my favorite sandstones together. I love finding concretions on field trips.

3. Pyrite: Living on the North side of the San Juan Mountains we are blessed with more than our fair share of water tainted with acid mine drainage. the pyrite to sulfuric acid reaction is always a favorite in my high school classes.

4. Calcite: Limestone is such a fun rock to find in the desert, not to mention the many calcite veins that my students are just positive are hydrothermal quartz veins.

5. Ice: I spent last Monday hiking up to and along a long ridge above treeline. The effects of alpine glaciation was just as dramatic as the more modern weathering taking place because of the many freeze thaw cycles we see at 12,000 feet.

Thanks for the idea of spending a comfortable 1/2 hour thinking deep geological thoughts. And, now back to work.


What a remarkable day for particle physics. They sure have big toys to work with, but at least my lab bench has always been the big outside! Check out this video about the Large Hadron Collider.

Monday, September 8, 2008

geoblogosphere survey

I just saw that NOVA Geoblog is taking a survey concerning who we are and what we are doing. The incredible growth of geology blogs in the past year has been mind boggling or is it mind blogging?? I started geo-blogging because I was hooked on finding the "Where on Google Earth" location but was never fast enough.

I am looking forward to seeing his final results. Go on over to NOVA geoblog and tell us all about why you blog about rocks.

Friday, September 5, 2008

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.

Sunday, August 31, 2008

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.


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.

Wednesday, August 13, 2008

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.

Monday, August 4, 2008


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.

Saturday, July 12, 2008

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.

Wednesday, July 2, 2008

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!

Monday, June 16, 2008

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.

Saturday, May 31, 2008

geology in the field

I have enjoyed reading about everyone getting excited about leaving the books and chalk boards behind and getting outside where the real geology is stored. My life is a little different. I mostly teach high school. We don't have field camps and their is absolutely no budget for fields trips (beyond to a nearby museum) anymore. However we use the Internet frequently (another great thread using the internet instead of the doing the real deal...but anyway)

So, in my case, I don't "do" geology as much as I "play" in geology, the next month schedule:
I am looking forward to seeing how the bigger water from last winter's snowpack will translate into rearranged sediment in some of the desert streams we frequent. Pictures will be coming as the play commences.

Have a great field season (summer)

Wednesday, May 28, 2008

Basic Soils, Starbucks and the Mancos shale.

The adobe badlands of Western Colorado are the erosional remnants of of the Mancos Shale, itself a depositional remnant of the Cretaceous Western Interior Seaway. The shale here in my back yard is made of very fine, organic rich materials that were eroded off of the newly formed Rocky Mountains and Uncompaghre uplift as well as some volcanic ash from somewhere west of home. You can read some more of this in Clastic Detritus' Accretionary Wedge entry.

But we wanted to create a garden. The Mancos shale erodes into a fierce muddy basic glop that is home to just a few hardy plants. So that is where Starbucks comes in. Occasionally, there are bags of old Starbucks grounds that are free to take for the sole purpose of lowering the soil's pH closer to neutral so that perhaps the tomato plants we stuck in the ground can actually live through the summer and produce fruit...

Stay tuned and lets see what happens at harvest time.

Tuesday, May 20, 2008

Accretionary Wedge, Spring Run Off

My favorite time of the year is spring. My wife and I go on countless "signs of spring" hikes at different elevations and have seemingly months and months of spring. (It is still winter above 10,000') Along with the various plants making their way towards the sun and blooms of different flowers showing their colors, one part of spring I look forward to every year is the spring run off. Small mountain streams slowly build throughout the day. Clear waters becoming more turbid as the discharge climbs with water that was snow just this morning.

The most significant geologic event to me is the spring run off in the Rockies. Every year this rush of water cleans out rivers, moves a boat load of sediment and provides great thrills for those of us who enjoy being particles ourselves and move down stream. Some years we get some big water, and this will be a big water year. You can stand above smaller streams and actually hear the movement of boulders along the stream bed. Rivers will overflow their banks in the "what was a flood plain before the housing development was built" and deposit smaller sized sediment that would enable great riparian health if we hadn't cut the trees down and built our houses there. The Animas Valley near Durango or the Yampa Valley near Steamboat Springs comes to mind. During the big snow years in the late 70's the whole valley would be there are really expensive houses there.

I have been studying the changes in sedimentation in the canyons on the Colorado Plateau as a result of the drought. We see larger particles sitting still for a number of years until there comes an event with enough energy to move them. These big snow years can be the energy event that an get this sediment transported a little closer to the ocean... And, its also great fun just to watch the power of big water.

Thursday, May 15, 2008

Words that bug

Callan over at NOVA geoblog has asked what words bug us. His rant discusses some of the words we have heard in countless conversations and term papers.

My rant is a small one and shows that my teaching is almost all at the high school level, but can you think of another way to say "a lot"? Some well meaning teacher back in the day pointed out to my students that "alot" is not one word but two "a lot" is a perfect use of grammar even if it is horrible word choice. I cringe and then automatically deduct a few points every time I read "a lot" in a formal term paper, and I read "a lot" of "a lots"

My favorites of course are the misspelled words. Just today I read about "comments" made of ice and dust that orbit the sun.

...and texting is something else altogether.

Wednesday, May 14, 2008

Did you feel it?

wow I can't believe so much of May has gone by already...time moves quickly!

I have 3 children who all live in different places. Two live in pretty active seismic regions (Guatemala and San Fransisco) and the third lives in a quiescent seismic area, Washington DC. So, I was very interested to read on Callan's and Tuff's blogs about the recent Washington DC earthquake and the amount of data collected from it, principally, the "Did you feel it?" information.

My wife was talking on the phone to our son when a M5.6 earthquake hit the bay area on October 31, 2007. As they I was able to get onto the National earthquake Information Center and watch their network do its thing and then start watching the map show who felt was pretty cool to watch.

Our daughter in Guatemala felt a smaller M4.8 event just last month. Now you would expect their to be fewer Internet connected computers in Guatemala especially since I am comparing them to Silicon Valley, and yes, the amount of information on the NEIC web site is minimal. But, our daughter tells us that the cell phone network of Peace Corps volunteers was busy that night as they all did their own reporting about who felt what.

However, I am not surprised that either location experienced an earthquake with far more energy than anything they experienced as a child growing up in Colorado.

Our third child holds one of those ubiquitous government jobs in DC and when I found out that she experienced an earthquake I was quite surprised. (I really shouldn't be as I have been learning about the violent geologic history of Washington and vicinity from NOVA Geoblogs.) The small M1.8 didn't slow down congress but did give her semi-geologist father something to talk about the next time she called.

What has been fun is being able to use these events to show my geology students how dynamic the earth really is and it makes for some great assignments! Currently of course the China earthquake and the eruption of Chaiten is a much more powerful reminder of how dynamic the earth can be and somehow gives more gravity to the lessons of earthquake theory.

Monday, April 28, 2008

Islands or Continents

I have been helping out an the elementary school where my wife teaches. Last week I had a smart little 4th grader ask what the difference is between an island and a continent. Of course I answered the continent was bigger. So, they ask why is Australia a continent and Greenland an island? I really had to think... Most of the geography answers really didn't help. But, the geology answers I came across seem to make sense, although the students did get that iced over look in their eyes as I rambled on about continental crust vs. oceanic crust, plates and geologically stable cratons. However, it was when I started to discuss the ideas of island arc accretion that I realized I had lost them. Perhaps next year.

Wednesday, April 16, 2008

volcanic ash makes great building materials

Spring break was spent in Guatemala visiting my daughter and her husband who are Peace Corps volunteers in the Western Highlands. On the bus ride between Guatemala City and her town near Xela, we passed innumerable small strip mines where some industrious locals have mixed the ash with lime to create cinder blocks which are used to build everything in modern Guatemala. In many cases, large piles of drying blocks are set out near the road.

The image above shows an ash mine with a cinder block building in the foreground. It turns out that this ash combined with a bit of lime is an excellent replacement for portland cement which is pretty pricey in the Guatemalan hinterlands.

Most of the Western Highlands are volcanic in nature with ash deposits, in many cases, 10's of meters thick and easily eroded making some interesting erosional features and some difficult terrain to get around. Most of the surface ash deposits are pozzolanic ash a fine, sandy volcanic ash originally discovered in the region around Vesuvius. This sandy ash is perfect for the production of cinder blocks and mortar as the deposits break apart easily. Unfortunately, I didn't do the homework I should have done before the trip and I found that poking around on Guatemalan private property was not a good idea. In Colorado I usually tell people I am studying the geology in their backyard...but my Spanish is not that good and I didn't need to start an international incident or make an ash of myself by examining the geology.

Thursday, March 27, 2008

Geology as Art

Last weekend we were walking past this alcove where you can see some pretty fresh looking Wingate sandstone. The exterior of the alcove has varying degrees of desert varnish while the inside looks virtually untouched. There is a nice large dark coating of varnish river right of the water drop off. When we climbed up to the alcove you could see lots of sandstone blocks with different degrees of varnish lying on the ground. As a rule of thumb I have always heard that a good thick layer of varnish takes about 2,000 years to develop. This is handy when trying to date petroglyphs or in this case rock fall.

I was always taught that the varnish is a result of biological action. Looking through my old notes I found thepaper by Dorn and Oberlander (Science Volume 213, 1981) where they state that desert varnish is formed by colonies of bacteria
absorbing trace amounts of manganese and iron from the atmosphere and wind blown dust and metabolically precipitate it out as a black layer of manganese oxide or reddish iron oxide on the rock surfaces. So for all of these years I have been teaching my students about the biologically mediated mechanism of desert varnish formation.

Well it appears that there has been some additional research done since my MA in 1989. There seems to be total agreement (as total as one could expect) with the material not coming from the parent rock and that there must be a mechanism to deliver the material to the rock surface.

Just by walking through the canyons you can see that the presence of water is integral to the process of desert varnish. I like the idea of atmospheric water using desert dust as condensation nuclei instead of bacterial action. Iron and manganese are found in the reservoir of desert dust which acts as condensation nuclei for the water vapor. Upon contact with the sandstone walls, the minerals precipitate out onto the rock. The water then evaporates and the excess dust blows away leaving the patina of varnish. I am concerned though as I have quite a reservoir of desert dust in the back of the jeep and I really don't need and minerals precipitating out on the window

This of course still leaves the question about the presence of bacteria, DNA and organic compounds in the varnish. Instead of being a part of the formation mechanism organisms might be coexisting in the developing varnish as it is being developed.

I don't pretend to be a chemist, geo or otherwise I just enjoy the puzzle of the origins of the patterns on the rock. But really, I usually just enjoy the desert varnish as geology as art!

Sunday, March 16, 2008

rock climbing lambs

Last Saturday was an awesome late winter/early spring day and we took advantage of the weather by hiking into Dominguez Canyon on the Uncompahgre Plateau. This Wilderness Study Area has an incredible display of petroglyphs all along a perennial stream, the appropriately named Dominguez Creek. The rock units are typical of the east side of the Colorado Plateau. The trail was constructed on the interface between the unconformable Precambrian "Black Rocks" as everyone calls them and the Triassic Chinle Formation. Just overhead are my two favorite formations in the canyons: the Wingate Sandstone and the Kayenta Formation. The Kayenta being a great caprock to the more easily eroded Wingate. These two units together create some of the more easily identified cliffs in the Canyonlands area not to mention that the desert varnish on the red rock creates some fantastic sunrises and sets (as an example, I made my family camp in canyonlands in mid November so that I could watch the sun rise hit the Wingate/Kayenta cliffs on the morning of my 40th birthday).

The Wingate tends to be a more massive cliff with some great crack climbing as in the Indian Peaks area. The Kayenta, I tell my students tends to be ledgey because it was deposited in a more wet environment. This also makes it easier to some places.

So, as we were hiking out of the canyon, we hear the baying of a young sheep on the cliffs above us. A group of four bighorn sheep were climbing the cliffs and it appeared that they were teaching two young lambs the finer aspects of crack climbing. The mom and dad?? (no anthropomorphizing here) were standing above the two kids cheering them on with a deep baying. One kid made it with little effort, but the second one was having troubles. We would watch him/her get a running start but never quite making the top. Each attempt ended with a fall back to the starting point and an earful of young sheep baying. We never did see the second sheep make it to the top. In the image, you can barely make out "dad" silhouetted against the skyline and a very small white dot that is kid #2 trying to climb the cliff

Thursday, March 13, 2008

Grand Canyon floods

...or at least the man made ones. Last week the Bureau of Reclamation opened up the jet tubes at Glen Canyon and increase the discharge from near 10,000 cfs to 41,000 cfs in an attempt to mimic natural high water spring runoff. The park service is hoping that they get some beach aggregation by moving sand from the stream bed onto the banks and make some sand bars. All this sounds like a fun experiment and I certainly would not mind being set on beach somewhere in the canyon to do some data collecting (sure beats being in a lab) but what I love is all the public accessible data that is created by these events.

In the summers I teach classes to K-12 teachers where we discuss teaching geology, at all levels, even in the elementary grades. I will put the graph above on the screen and ask them what happened. This country has a lot of great K-12 science teachers, but unfortunately many of them have little experience working with real life data or at least data that didn't come from the book. These public data sites are awesome and can be used to teach something at every level. Needless to say, the high school teachers have a slightly different take home message that the pre-school teachers do but they all leave saying that they can use something in their classes.
After a day spent in a lecture hall, we get ready for the field portion of the course where we canoe through some incredible Utah canyons, trying to be particles traveling with the current towards the ocean and coming face to face with some incredible geology...after all, somebody has to do it.

Thursday, March 6, 2008

Death defying geologists

Being new to the geoblogosphere and not reading and/or posting every day I find that I have come in late to some of the great death defying posts that others have shared. Last summer we were traversing under a pretty rotten cliff face(volcanic breccia) when we heard a rifle-like-shot come from way above and we witnessed a rock fall that featured a compact car sized rock hitting the road where I am standing in the picture. It was pretty fascinating to watch the whole event, so much in fact that even though we had cameras in our hands no one thought of videoing the rock fall or the resulting dust cloud. The rock hit the road with a thud and then bounced off the other side to the valley bottom.
As I say...Geology Happens

Friday, February 29, 2008

more snow

Today I had the opportunity to ski near Red Mountain Pass in Colorado's San Juan Mountains (the other side of the mountains from All My Faults are Stress Related) when I skied next to the Idorado Snotel measuring station. I just had to take the picture that backs up my last post that we have a boat load of snow here in the headwaters of the Uncompahgre River. Yes, the chain link fence surrounding the station is a full 6 feet high.

Wednesday, February 27, 2008

snowpack in the rockies

I have had the greatest time reading geology blogs such as Apparent Dip. Magma Cum Laude, The Lost geologist, NOVA Geo blog and Ron Schott's page and thought I would join in the action. I didn't link these blogs as I thought it would be presumptuous on my part without asking them.

One of my passions is watching how changes in each winter's snow pack influences how our spring and summer will behave. This is especially true for those of us who are looking forward to river trips in the warmer weather. Also I love data!

This graph courtesy of the National Resources Conservation Service. The black line shows this year's totals to date as compared to the last few years and to the 30 year average. It is plain to see that we are on track for record breaking snow in our river basin. But, what is interesting to see is how quickly the snow melts once the weather turns warm. A study done at the University of Colorado shows that the snow in the upper Colorado Basin has melted out about o.4 days earlier per year over the last 30 years for a melt out two weeks earlier than the 1970's. What will this year look like? A fast melt with flooding? A slow melt with full streams throughout the summer? Stay tuned to find out.