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Geology of the American Southwest  For friends and IUP alumni who want to see all our journal entries and photos from the May 2005 Geology of the American Southwest field trip, here's a quick navigation aid (since the students' journals date from last May, they no longer show up on my "Friends" page). To start reading my overview journal from the beginning of the trip (May 9), click here and navigate forward a day at a time. To read Dr. Jon Lewis's journal in the same way, click here. Dr. Lewis goes into a lot more detail than I did about the geologic features we saw and discussed along the way. It's probably the best journal to read if you're really interested in going to any of these sites on a vacation or field trip. The students' journal entries can be found by following these links: Dana Mazur Justin Reed Kalin McDannell Mallory Zelawski Tim Hazen If anyone is headed out to the Southwest or the Eastern Sierra Nevada on a family vacation, please feel free to get in touch with me for logistical information or directions to any of our field sites. And if you're an IUP alum, don't forget to take some pictures and send them in for the online newsletter! Today was our last day in the field, and it was also about the hottest weather we had outside of Death Valley! We camped near Moab and spent the morning visiting the Island in the Sky, which was a high triangular mesa where Canyonlands National Park and Dead Horse State Park are both located. From way up high, you can look down on the Colorado River and see how it meanders through towering rock cliffs.  The IUP students put on their thinking caps (which look a lot like cowboy hats!) and managed to puzzle out why such a powerful river is taking such a "lazy" path on its way down to the Grand Canyon. For more details, check out their journal pages. Later that morning, we visited Upheaval Dome, a mysterious place on Island in the Sky where the rocks seem to have burst upward. No one knows for sure why this happened, but there are lots of different possibilities. Check out Dr. Lewis's journal for more on the spirited debate we held over the origin of this feature.  Finally, we spent the hot afternoon driving through the fantastic scenery of Arches National Park, just across the valley from Canyonlands. The rocks here are very different, thanks to the Moab fault which lifts the west side up relative to the east side. Huge salt deposits have bulged up under the ground at Arches, and cracked the rocks into long narrow "fins" which make natural arches quite easily. The IUP students scattered out in all directions to take pictures of these unique structures -- check out their pages to see them!  Tonight, we're going to celebrate the end of the trip with a pizza dinner and a good night's sleep. In the morning, a few hardy students are going to hike up to Delicate Arch to view the sunrise, then it's back to Indiana and home. Thanks for sharing the trip with us ... hope you enjoyed it! Dr. C. We made a long and snake-shaped drive today, from the little town of Escalante in southwestern Utah to the much bigger town of Moab in eastern Utah. Along the way we saw two outstanding geologic features. First up was Capitol Reef National Park, with its famous Waterpocket Fold. This colorful region shows off all of Utah's Mesozoic rocks, from the red Moenkopi and purple Chinle up to the white domes of the Navajo Sandstone. Apparently those domes reminded early travelers of the US Capitol in Washington DC.  Hmm. Do you think maybe they were squinting against the sun to see that? Or just sun-struck?? After Capitol Reef, we drove south and crossed the Colorado River at Hite UT, which is where Lake Powell begins. From there, we drove east through White Canyon, a bare rock valley named for the "petrified dunes" of white Cedar Mesa Sandstone that cover its floor while dark red mesas of Moenkopi and Wingate Sandstone march along its walls. Almost hidden in the winding mesas of this canyon are three of the best natural stone bridges in the world. Each one has been given a local Native American name -- the one below is Sipapu Bridge, named for the Pueblo sacred passage that leads to the spirit world.  For more details on the kind of fold we saw in Capitol Reef, or on the geologic processes that form natural bridges, check out any of the student journals on the friends page! And be sure to join us again tomorrow, when we'll finish our virtual field trip by visitng Canyonlands and Arches National Parks in Moab. After leaving Bryce Canyon, we traveled to a little-known state park called Kodachrome Basin to look at the Entrada Sandstone. This bright orange rock is like a younger little brother to the Navajo, since it also formed in a desert environment. Here at Kodachrome Basin, the Entrada is full of very tall, rounded columns called "stone geysers".  The students puzzled over the formation of these strange rock units for a while before figuring out that they were the result of ancient earthquakes. Check out their journals for more detailed information on the process that formed them. Later in the afternoon, we drove further north up the Grand Staircase to Escalante Petrified Forest State Park to see another, younger example of petrified wood preservation and to swim in a nice, cool lake. Since it's in the upper 90's here, we all appreciated that! We started our morning by driving through the long Mount Carmel tunnel and then hiking up the Canyon Overlook trail to examine the giant crossbeds of the Navajo Sandstone at close range. The students took a few moments at the top to appreciate the scenic beauty of this park.  After leaving Zion, we traveled to Bryce Canyon National Park. If you think of the Colorado Plateau as a giant layer cake, then Bryce Canyon is the pink and white "frosting" on the top (with some volcanic "birthday candles" in places here and there!) The scenery here is almost overwhelming, as the rocks break down in so many places that they create columns called "hoo-doos".  We spotted a neat-looking basalt flow along the interstate on our way to Quail Lake, so first thing this morning, we drove back and found a new road that cut through it.  This flow turned out to be a classic example of inverted topography, where a lava flow filled an ancient valley two million years ago. Since then, the soft clay hills on either side of that valley have eroded away, but the basalt flow is so strong that it is now the highest part of the landscape. This was also another good example of columnar jointing, similar to the Bishop tuff we studied back in California. Later in the morning, we drove into the main canyon at Zion National Park and studied the hanging valleys and slot canyons developed along the Virgin River here. The sheer cliffs of the Navajo Sandstone rise hundreds of feet above the canyon floor, creating shady alcoves where springs support hanging gardens of columbine and maiden fern.  The students really enjoyed walking along the shady river, since the temperature out in the main canyon was in the upper 90's. Tomorrow, we’ll drive out through the long Zion-Mount Carmel tunnel to visit Bryce Canyon National Park, and then go on to study the rock layers of the Grand Staircase National Monument. After camping in a peaceful pine forest, we spent the morning looking at the amazing cave formations inside Lehman Caves at Great Basin National Park.  These caves are not as popular as Carlsbad or Mammoth, but they have amazing cave formations, such as tiny delicate columns and parachute-shaped shields. For more pictures of these gorgeous cave decorations, check out the student logs on the ‘friends’ page! After leaving Great Basin, we traveled across the easternmost Basin and Range and climbed back onto the Colorado Plateau, the area of high flat rocks that contains more scenic wonders than any other region of the United States. For example, here is the view from the Kolob Canyon scenic drive in Zion National Park, where stunning vertical canyons are carved out of the massive Navajo Sandstone.  We ended the day by singing “Happy Birthday” to Dr. Lewis at our new campsite on Quail Creek Lake. 
We drove today from Big Pine California in the Owens Valley all the way across the Basin and Range region of Nevada to Great Basin National Park. This is one of the newest and least visited parks in the country, but it is spectacular. It includes Mount Wheeler, below, the second highest peak in Nevada.  At sunset, we drove up the Mount Wheeler Scenic Drive as far as we could (the top thousand feet was still snowed in!) to look at the rocks that made up the mountain. They were very hard because they were a slightly cooked sandstone, but they still showed primary features such as crossbedding. The students also demonstrated that the layering here is oldest to youngest by putting Tim (a senior) on the lowest ledge, Ryan (a junior) on the middle ledge and Mallory (a sophomore) on the highest ledge. 
When you think about major volcanic hazards, does eastern California come to mind as one of the places we should be worried about? Probably not, but after spending a day in Long Valley Caldera, you just might change your mind! This entire area is a collapsed volcano that erupted 730,000 years ago and still shows signs of continuing volcanic activity today.  We started our geology studies today at Hot Creek, a geothermal site where groundwater that has been heated by underground magma comes boiling up to the surface. Dana Mazur gave a presentation here on fumaroles, which are vents where superheated steam rises to the surface through narrow cracks.  After leaving Hot Creek, we traveled north to the Devil's Punchbowl, which is one of the Mono-Inyo craters. These are very young volcanos that erupted obsidian and pumice only a few hundred years ago. They are very steep, which made hiking up to the rim a real effort above 7000 feet of elevation! But it was worth the work, because once we got to the rim we could actually see the inside lining of the volcano's "throat" with its flow structures and tension cracks. After collecting lots of obsidian samples for the department's rock collection, we hiked back down Devil's Punchbowl and headed up to Mono Lake to take a look at its volcanic islands and tufa towers. The islands in this lake are also volcanos, and formed during the recent Ice Ages.  Our final stop of the day was the Hilton Creek Fault Zone. This is one of the many faults in the Owens Valley which helped to open cracks for the magma to rise through. The map below (courtesy of the USGS) shows how all of the features we saw today are related. The area marked "resurgent dome" is where the next volcanic eruption just might happen! 
We woke up in a windstorm this morning, and had to study geology inside for an hour.  After that, we drove north to Bishop California and hiked down the Owens River Gorge to study the Bishop Tuff. These thick volcanic layers formed when the Long Valley Caldera erupted (like Yellowstone) over 700,000 years ago. As the hot volcanic ash cooled down, it cracked in long pillars called “columnar joints” to form the spectacular view you see here.  Tonight, we’ll stay at Big Pine in an educational camp called Bernasconi Center. We’ll spend the next few days studying the tectonics and volcanic features of Owens Valley before heading back across the desert to Great Basin National Park. |
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