New Accretionary Wedge

I think this will be AW #23.

Not everything I am studying ends up in a published paper, well actually nothing I study ends up in a published paper. Sometimes my HS students hear about my adventures and sometimes I write a blog post, but mostly it is just for me.

This AW is to share your latest discovery with all of us. Please let us in on your thoughts about your current work. What you are finding, what you are looking for. Any problems? Anything working out well?

Lets try to get everything in by March 26. I will be out (mountain biking in the field) for the 1st half of April and I want to get this done before I head out.

The Grand Mesa

What a fabulous President's Day, a ski tour atop the "largest flat topped mountain in the world". The Grand Mesa is a large mesa found in western Colorado. I am not sure who decided that it was so special, but I read it on the Internet...so it must be true.

The top of the mesa is covered by lava flows dated at 10,000,000 years ago. These lava flows make quite a nice cap rock and have slowed erosion down. The top of the mesa sits a little over 11,000 feet, and in the summer the volcanic evidence is abundant. In the winter, not so much. On either side of the mesa, the Colorado River to the north and the Gunnison River to the south, deeper valleys have been incised down to 5,000 feet in elevation.

Because we can date the lava flows and we can measure the depth of the valleys next to the Grand Mesa, it makes for a very convenient yard stick. I teach geology classes along both the Colorado and Gunnison Rivers. By doing some simple math, (6,000 feet in 10,000,000 years) we get an idea how long it takes for neighborhood valleys to erode. We then measure nearby tributaries and get an idea how long that tributary has been down cutting. I love getting simple math into classrooms!

The Grand Mesa is important for more than just being a yard stick. It is a formidable barrier to moisture as it makes its way east. The south side of the mesa is part of the Gunnison River drainage while the north side of the mesa is part of the Colorado River drainage. Much of the water needed throughout the arid west will be dropped here as snow each winter.

The Grand Mesa seen from a distance. It makes an obvious landmark for mile around.

A summer time shot from the valley bottom.
Winter! Skiing next to a basaltic ridge.
The state flower, The blue Columbine growing among vesicular basalt boulders.

Flash Wedge

Fearing the demise of the geocentric carnival, several geoblogosphere members started a flash wedge. A sort of meme carnival or a carnival meme. So, I thought I would join the action.

I have been working with a group, Teachers Without Borders. They did some great work with the recovery of the large 2008 earthquake in Sichuan China. Those lessons will be used as the recovery occurs in Haiti. Currently, TWB has a one page "this is what happened" link that explains some of the science, how to contribute and some resources.

to borrow from John McPhee

I really needed a Californian.

Our 1st grandson was born about 1 month ago and we (being the grandparents we are) traveled to San Francisco to help our son and daughter in law make that transition from not-being-a-parent to parenthood. You know where you don't get to sleep any more. What a fun place to watch your new grandson. They live on top of one of the famed SF hills and there are outcrops all over the place. I have become lazy with the Colorado Plateau outcrops where the story is somewhat easily interpreted. Not so in SF! Pretty much made little sense to me. So, went to a book store and started researching. That and geotripper's posts sure helped. Thanks!

Most of the pictures taken were of people holding a baby. I will try and find one with people holding a baby next to a rock and post it.

teachable moments

The Haiti earthquake happening right on the heels of the Eureka earthquake has brought tectonics into almost every elementary classroom in the region (and I would imagine most everywhere else also). Because of my geology background and flexible schedule, I have been asked to discuss the geology of these events in a few of these classrooms.

I would like to thank all of the bloggers in the geoblogosphere. Your posts have helped me sound like I almost know what I am talking about.

Avalanche

Last week we saw our first major accumulation of snow. In some places there were reports of four feet! Not so much here, but a blue sky day and new snow that was just aching to be skied on. We climbed up into the basin, and noticed very few ski tracks and a few recent avalanche paths, including this one large slide.

The crown fracture line was just a few feet deep. You can see the major slide and then a smaller sympathetic slide right next door.
The debris crossed the valley, all the way to the small drainage.
A little over exposed (I don't know who left the setting at 1600ISO?) But this gives a better idea of the size of the event. We skied a little closer and then turned around and went someplace safer.

traveling meme

Well I haven't posted for quite some time due to some family traveling, with night time flying and events where it would be extremely bad form to photograph any surrounding outcrops.

Most of my field trips are close to home, the San Juan Mountains in SW Colorado and the red rock canyon country of Utah. I will also admit that most of the geology I do is done on the back of a mountain bike. My wife calls in recreation, but I am convinced we are doing real science.

This year, along with visiting my usual nearby haunts, there were three trips further afield. In April, my first trip to Hawaii! June saw us visiting Yosemite. Much of August and September was in New England helping family members.

Skiing near Red Mountain Pass last January

The black sands of Hawaii during spring break

Eye of the Whale arch in Arches National Park

Exploring Keg Spring Canyon and finding some great examples of late Paleozoic petrified logs.

Iconic Yosemite valley

Teaching a field class while floating the Colorado River.

Riding in Crested Butte. Great flowers among spectacular mountains.

The Colorado River flowing through an anticline.

As each year progresses, the to do list for the next year gets longer. 2010 is no exception. Hopefully there will be lots of time in the field, because as every geologist knows, life is a field trip.