Friday, April 24, 2009

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.  




Monday, April 20, 2009

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. 

Wednesday, April 15, 2009

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.

Monday, April 6, 2009

Spring break in Hawaii

Just back from a week in the tropical rain of Hawaii. We visited Hawaii Volcano NP and peered through the mist to see what could be a caldera...any way more of that to follow. This was also a visit to the only state I had not been to.