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. 

Dirty Snow

I spent the other day checking out the early May snowpack on Red Mountain Pass here in the San Juan Mountains...some one had to do it!  Our winter produced an above average snowpack (just barely) which bodes well for the summer wildflowers and low elevation irrigation, but it is melting rapidly. This winter also produced three strong wind events that blew red dust in from Utah. The higher elevations were covered in red snow while the lower elevations saw muddy rain. The dust on the surface of the snow impacts the albedo and less solar energy is reflected back into the atmosphere. In addition, the desert dust that is mixed throughout the snowpack has a different specific heat than the snow. As the spring temperatures warm, these dirt and dust particles heat up faster and in turn melt the snow faster than historical records would suggest. Snowpack that once would last into July is now melting out in June. Rivers which should run high into the early summer peak out in May.

The last image shows the current state of the Gunnison basin snowpack. The smooth line represents the 30 year average. Look at the slope of the last few years of snow melt. I think there is a message here.

dirty snow at 11,000 feet

harder to see, but the snow fields are covered in dirt

National Park Week

National Parks have been called the best idea America has ever had. I have to agree. This past week has been National park week, a time to celebrate our idea to set aside and save some of the best that our country has to offer. Its a hard job to balance the millions of visitors parks get every year with the mission of protection.  

In the late 1980's, I actually postponed grad school graduation ( I was one course shy of finishing) because of a job offer with the NPS, in my favorite national park. I was a ranger in Rocky Mountain national park for 3 summers. My kids will tell you that those summers were their favorite 

while growing up. I worked in a campground, was trained to fight forest fires, helped with search and rescue and was impacted for the rest of my life. It was also handy that my graduate work was all in trying to make sense of the different glaciations the Colorado Rockies had seen. I was working in my field area :)! and, yes that is me in the Smokey the Bear hat.

Since then, I have been a enthusiastic visitor to as many different national parks as I can every year. This would be a good place to start a "how-many-parks-have-you-visited" meme, but I am too lazy to make a list. Buy the pass, even at its newer-higher "Bush era" price increase its still the best deal in America.  

concretions

A portion of last weekend was spent walking through Ute canyon in the Colorado National Monument.  In some areas we were walking across an eroded Wingate surface. The Wingate sandstone is early Jurassic in age and is a windblown quartz dominant sandstone with obvious crossbedding through out the formation. While walking on the Wingate (or the Navajo ss) there are sometimes collections of small marble like objects on the ground. These marbles are iron concretions. 

When the rock was originally going through the rock forming process a thin patina of hematite coated the quartz grains creating a cement holding them together.  Later, water (with certain reducing agents) moving through the sandstone picked up the iron. When this dissolved iron combines with oxygen the dissolved iron loses an electron and its solubility is reduced.  The hematite is immediately precipitated out forming the iron concretion.

This process happens all through the sandstone creating all sorts of shapes. The marbles are the most common, but concretions can be found as buttons and towers and sheets along the ground. As the softer sandstone erodes away, the harder concretions stand out making a surface of small marbles. 

Hawaiian volcanoes

I have to thank my fellow geobloggers for giving me some ideas for my Hawaiian vacation.  Spring in the Rockies can have glorious weather that allows for quality time outside, or it can be snow and cold and wind, with the emphasis on the cold and snow and wind. What better time to visit Hawaii?  Our choice of the big island was easy, where else do you get to combine all of the earth sciences? Geology was everywhere we looked, with the concentration of course being with volcanic rock. Astronomy was well represented by the Mauna Kea observatories and oceanography is self explanatory.

We did see steam rising from the ocean as new lava poured in. The NPS sure wanted to keep us safe so the view was a distant one. The highlight here was the walk across Kilauea Iki, the smaller Kilauea caldera. There are no pictures as it was raining too hard to get the camera our or to see anything.

What I found amazing was to hike across large open areas of fairly new lava flow. It must of been quite a sight watching lava pour over this cliff.  The biology was incredible watching the succession of plants create soil.

The black sand beaches were fun just to play in.  It was hard to imagine the interaction between the hot lava and the cooler water while we were playing in the sand watching sea turtles in the surf.

Just a reminder of the earthquakes that can occur around the Pacific Rim. This is definitely an image that will make it into my class slide shows.

What a tropical look. The lava flows coming right down to the ocean with palm trees on the beach...I could live here.