Out of context

Callan talks about desk crop-samples. Here are two examples of "parking-lot-crop-samples".

How many times has someone come up to you as a geologist and asked you to identify a rock sample? How many times has the sample in question come from a nearby parking lot? This happens to K-12 teachers all of the time.

Many K-12 teachers are not geoscientists and I tell them that context will help them in trying to identifying the rock sample. They must ask the kids about the location that the rock came from. It helps the kids in creating the description of the

their rock sample as well as giving you an idea of what the name is .

I was particularly interested in how the crystalline sample was found next to the conglomerate sample. It is obvious that the they did not originate in the same place but both had been transported to this location. This can lead to a great discussion about how rocks can be moved: water, wind, truck.

Over the years, these parking lot samples have kept me on my toes, especially that one GEO 101 lab where the TA gave me some aged concrete to identify. I quickly learned that lesson.

Why Geology?

In response to Magmalicious' question about why I ended up as a geo-scientist instead of perhaps a stock broker??

Neither of my parents nor anyone in my immediate family was interested in science...never mind the geo-sciences. It was in high school when I found that the landscapes I had been walking, climbing. biking and canoeing through had stories that could be teased out of the rock. It seemed that by following a few simple rules anyone could piece together this tale. I was hooked. What other field allowed me to be outside all the time and to do real science?

Studies in glaciology let me see why our backyard was full of cobbles from distant places and why the nearby lake was called a kettle pond and why Cape Cod is so rocky

Later, as an undergrad in Colorado, learning how seas had come and go through the years creating alternating layers of sandstone and shale out on the Eastern plains.

And then I found western Colorado with tertiary volcanics and sandstone canyons.

I decided to enter the world of the K-12 science teacher. In that time I figure that I have seen over 3000 students. I hope that I have shared this love of the outdoors, the story of landscape formation and how we can tease information out of the very rocks themselves.

Class time

One of the greatest classrooms I have ever had the opportunity to use has been the Colorado River. We spend 3 days camping and canoeing and doing geology for a teacher enhancement course. That means I teach teachers some simple geology and we all share ideas how we can bring kids into the world of rocks and rivers.

Looking down into the Grand Valley on day 1.

Canoeing past Entrada walls

Hiking into side canyons. Here the stream cuts into pre-Cambrian "Black Rocks" dated at 1.7 b.y. and is overlain by the Chinle formation aged approximately 0.2 b.y. Everyone thought that walking on 1.5 b.y of missing time was an impressive Saturday afternoon stroll.

getting ready

The arches of Mee Canyon. The erosive potential of the Wingate sandstone is seen here. The Kayenta caprock is missing and the windblown Wingate creates evenly placed joints that erode into columns. Our lab that day was to establish the height of the columns and then using the average local incision rate of 0.14 ft/1K years to calculate how long this canyon has been around...a fun time with math!

The crew

Summer vacation continued-Sierra Nevada

After leaving the Silver State we made our way to Yosemite. I had last visited as a 12 year old kid but I had some expectations after reading through geotripper's travelogues. I had read his posts and in the text books, I understood the batholith that is today the granite of Yosemite...but it was the brilliant white       of the rock that took my breath away.  The granite's that I have played on have not been as white as what I saw in Yosemite. The image on the left is the view of Yosemite valley that we saw. The white is not the granite, but a meteorological event called a storm. 

All the rain of the day before translated into some incredible waterfalls. Most of the water falls entering Yosemite valley are from hanging valleys, a byproduct of the last ice age. Here Nevada falls makes its way downward towards the ever popular and aptly named mist trail. The mist trail is in near Vernal falls and every hiker is "misted upon" making a favorite hike on a hot day.

The rocks along the roadside in King's Canyon showed a little bit of deformation here. From what I could find, this area was positioned immediately above the great batholith as a pendant of former rock. It was not quite melted but sure had some significant changes take place.

What visit to the Eastern Sierra would be complete without a visit to the Devil's Postpile. This classic... nay textbook example of columnar basalt was at the end of a short fun hike.

I remember when I read John McPhee's annals of a former world, he made a statement about needing a Californian to understand the geology of the Golden State. I am sure glad that there were a variety of guide books as well as geotripper's comments to help me along a great road trip.

our summer vacation-Nevada

It has been awhile since my last post and actually its been awhile since we had regular Internet access. This is just a quick update.

 The summer started with a whirl wind trip to Yosemite. We crossed Nevada and did some  geology at 70 mph. We stayed a total of 3 nights in the Silver state. Our very first night of the trip was spent in Cathedral Gorge State Park. Very cool place, reminded me of the Badlands of South Dakota. The sediment is all from a Pliocene era lake bed. The erosional features are cathedral looking hence the name. The best part were the long narrow gullies that are called "the caves".  The picture on the left is from inside one of the gullies.  The picture below is one of the Cathedrals in the park. We then took the extraterrestrial highway to the Sierra Nevada mountains.

 Our final stop on the tour was in Great Basin National Park. We visited years ago and said we needed to visit again. What a fantastic representation of the basin and range province. 

Unfortunately it snowed quite a bit while we were there and we couldn't see everything we wanted to. What amazed me the most was the elevation change from the desert floor to the summit of the park...over 8,000 feet.

more to come when time permits...

summer reads

The summer season has been busy already. I had 5 fantastic days doing geology through Labyrinth Canyon with a Denver museum. There were 4 of us geologists all with different specialities and a boat load of interested lay people with us. Great fun! We are now getting ready to visit Yosemite and some places in Nevada (I have been studying Silver Fox's posts to get a lost together). The editors of my latest writing assignment have been busy so if I am not packing I am fixing edits.

But

I am also getting a list of geology books together for the back of the truck. I am re-reading McPhee's Basin and Range and Assembling California for our next trip.

Let's get a list together of great geology books that we can all read this summer!

Playing in the Entrada

Way back in the mid Jurassic, about 150 million years ago the Colorado plateau region of Utah was in the middle of a huge, Sahara-esque desert. Sediment from the rising mountains in Nevada blew across western Utah and was deposited in huge dunes in what we now call the slick rock member of the Entrada formation.  

The Entrada formation is divided into three members, the middle member, called the slick rock member gets most of the press. The oldest member is named after the now burned-to-a-crisp Dewey Bridge. It consists of siltstone and is a holdover from the underlaying Carmel      formation. The oldest portion, called the Moab 

member slowly grades into the Summerville formation. 

But it's the middle member we all go to Arches NP to see. These last two weekends were no exception. The first few images show the landscape near the Herdina park section in the national park. We wandered around this sandstone island finding balanced rocks, arches and alcoves.

Eye of the Whale arch

This past weekend was looking at the arches in the Black Ridge Wilderness. The trail starts at the river and climbs, sometimes steeply as evidenced by the BLM trail marker.

At trails end is the second largest concentration of arches in the US.