Today Travis, Dr. Pollock and I started our field work in Undirhlíðar Quarry. It was cold, windy and rainy- perfect for our new rain gear!
Geochemists at work
We started mapping the quarry walls in detail where Becky Alcorn ’11 left off, and made it along the East wall in about six hours. We observed some gorgeous pillow lavas, the most abundant formation in the quarry.
Pillow from the East wall
Undirhlíðar is much larger than I had originally imagined it (certainly a grander scale than Estonian quarries). Here’s a great picture taken by Travis:
Undirhlíðar quarry wall under consideration by Dr. Pollock and Lindsey Bowman
To brighten up this post, I’d like to nod to the colorful and abundant flora of Iceland. Barren? I think not.
Nootka Lupin outside Undirhlithar
Wood crane's bill
The only fauna that we’ve seen besides seagulls are these unfortunate fish- species unknown.
Dried fish- yummy!
Finally, below is a video taken by Travis today to give you an idea of Undirhlíðar in 3D-
Tomorrow we head to Vatnsskarth to continue our field work!
WOOSTER, OH – Students in the Geology of Natural Hazards course spent a day studying the products of volcanic eruptions. Here are some of the outstanding samples in our volcanic collection:
Reticulite is a delicate network of basaltic glass that forms during Hawaiian fire fountaining. Volatiles expand easily in the low-viscosity magma, creating a dense network of interconnected vesicles separated by thin strands of quenched lava (sideromelane).
Accretionary lapilli are rounded pea-sized pieces of tephra that consist of volcanic ash. Ash aggregates into balls because of electrostatic forces in the eruption column.
Volcanic bombs are formed when lava is ejected and becomes airborne. The fusiform bomb has a rounded aerodynamic shape with an elongated tail, which tells us that the material was molten when it was ejected and was shaped as it traveled through the air.
The glassy surface of this basalt shows the classic ropy texture of pahoehoe. Ropy pahoehoe develops when the surface of a lava flow becomes partially solidified and wrinkles as the underlying lava continues to flow.
ZZYZX, CALIFORNIA–This morning the Wooster Geologists enjoyed an ancient lava flow from the inside. We found our way to a lava tube near the center of the Mojave National Preserve and explored the interior with flashlights and flash cameras. It helped that there were a few “windows” in the basalt roof where sunlight could stream in. As Meagen Pollock (she who lives for basalt) explained, a lava tube is formed when a flow cools on its exterior portions while the lava is still moving. When the lava drains out at the end of the flow, the result is a long tunnel of basalt. Lava dripped from the ceilings, making the igneous equivalent of stalactites. As the flow receded, it left horizontal “bath tub rings” along the side of the tube. It was fun to speculate on how many lava tubes remain undiscovered beneath the many square kilometers of basalt exposed in the Mojave Desert.
ZZYZX, CALIFORNIA–This afternoon the Wooster geologists studied two very different magma products in the southern part of our field area. After lunch we drove to Amboy on historic Route 66 and then hiked up to the rim of Amboy Crater. Here we saw the extrusive, mafic rock basalt at its finest in the cinder cone itself and the lava flows across the valley.
Desert iguana on the basalt near Amboy Crater.
After Amboy, we traveled north to the Granite Mountains and examined wonderful alkali granites weathering into rounded boulders. The feldspar crystals in these intrusive felsic rocks were extraordinarily large and numerous, and there were many xenoliths scattered throughout. The countryside here was lush with desert vegetation that made our all-too-brief stop most enjoyable.
WOOSTER, OHIO–”When College of Wooster Assistant Professor Meagen Pollock stands in front of one of her geology courses, she’s thinking beyond what her students need to accomplish during that class period, or even during that semester. Pollock is constantly thinking about how she can ensure that her students—all her students—develop good research skills.” This is the beginning of an article in the October 2010 AAC&U News, a widely-read publication of the Association of American Colleges & Universities. The topic is Wooster’s signature Independent Study program. Katie Holt of the Wooster’s Department of History is also featured. We are very proud of our colleagues … and just love the fact that one of our geology students in the field is pictured as an example!
Ali Drushal Sloan ('09) doing Independent Study fieldwork in northern Iceland.
After hiking through the Tetons, we continued our tour of Yellowstone by visiting a number of places in the eastern and northern portions of the park. We visited Signal Mountain Summit, which is a great overlook of the glacial outwash plain due to the glaciation of Yellowstone. (However, I was just as fascinated by the little black bear that we saw on the drive up to the summit.) We also stopped at Artist Point, south of Canyon Village. (We actually stayed the night in Canyon Village’s cabins.)
Then, our journey took us to Norris Geyser Basin, Obsidian Cliff, Sheepeater Cliff, and the Mammoth Hot Spring Terraces. All I can really say is “Wow”!!
Above is a scenic view of one section of Norris Geyser Basin, which had some of the most interesting thermal activity in the park.
Take a look at Sheepeater Cliff, which is composed of basalts that exhibit columnar jointing. Sheepeater Cliff is a result of the bimodal volcanism that was present in Yellowstone.
Mammoth Springs provided some wonderful exposures of travertine terraces, several of which were very active.
Of course, along our journey we made some friends, such as this moose grazing along the river bank. It was amazing how one creature could tie up so much traffic!!
Yet another friend...a very, very large bison.
The day ended with a trip to the Gardner River. The picture above shows a small stream of thermally-influenced water flowing into the Gardner River. Along the river bank, temperatures are easily over 100-110 degrees F, and thus many people enjoy one of nature's very own hot tubs. But, if you walk just a few feet out into the main portion of the Gardner, the water is ice cold.
FRANKFURT, GERMANY–Isn’t that a great front yard for a Natural History Museum? Diplodocus longus strides by columnar basalt and a massive chunk of conglomerate. This is the Naturmuseum Senckenberg in downtown Frankfurt, about two blocks from my hotel. On my last day in Europe I met with Dr. Mena Schemm-Gregory, a brilliant young paleontologist who specializes in brachiopods. I was very impressed with the labor-intensive way by which she makes three-dimensional reconstructions of brachiopods embedded in matrix, including their internal structures. I also simply enjoyed the museum displays. This is a good way to end this eventful trip — a visual survey of the history of life!
The front of the Senckenberg Museum, which was built in the first decade of the 20th Century. The tall object on the left is a life-sized reconstruction of a Carboniferous seedless vascular plant. I'm cleverly using it to hide an annoying smokestack in the background!
Close-up of a massive piece of Banded Iron Formation also standing outside the museum. This one is anywhere from 3.5 to 1.9 billion years old. It represents a complex interaction of ancient microbes, seawater and the atmosphere which is still not completely understood.
Even the living plants highlight life's history. This is a branch of a ginkgo tree, a group which has an ancient lineage extending back to the Triassic. Er ist ein "Lebendes Fossil".
Today, we ended the indoor classroom portion of the Teaching in the Field Workshop with a lively discussion on the use of technology in the field. Everyone seemed to agree about its usefulness in research; however, there were many different views when the discussion turned to the use of technology in the field when teaching students how to map. Digital mapping is used by state geological surveys and the USGS, but the techniques are not universally used in the classroom and in field camps across the country. When this friendly debate was concluded, it was time for dinner. Instead of eating in the conference room in the student union, the workshop coordinators had organized a picnic for us overlooking Hyalite Reservoir.
Hyalite Canyon is located just south of Bozeman in the Gallatin Range, and it exposes rocks of all ages — Archean gneisses through Eocene volcanics. Before dinner, we hiked to Palisade Falls for a spectacular view that underscored the fact that I was definitely not in Ohio.
As we walked to Palisade Falls in Hyalite Canyon, we followed a wonderful stream flowing through a sub-alpine forest.
Palisade Falls, shown above, was gorgeous during the early evening light.
Notice the wonderful columnar jointing that makes up the wall for Palisade Falls. It was very difficult to pull 50+ geologists off of this outcrop, but dinner was ready!!
The rest of the week, the workshop on Teaching in the Field is actually taking to the field to put boots on the ground.
CHRISTCHURCH, NEW ZEALAND–Andrew Collins, our Wooster Geology student abroad in New Zealand, has posted another set of photographs from his adventures. Of course they include field geology! Here is one of his images from a recent outing:
Cave Rock near Sumner, which is a suburb of Christchurch, New Zealand. Photograph by Andrew Collins.
This view fits into one of our major themes this year: basalt! We had plenty of it on the Mojave field trip, the Utah group dabbled in it, and the Iceland team is defined by this dense black rock. Now I’m no expert, but here’s my interpretation of the above outcrop: it looks like a basalt flow over a coarse conglomerate with a magnificent baked zone at the top of the conglomerate (the bright red) and a chilled zone at the base of the basalt. What do you think?
Unfortunately this is our last night in Iceland so I will not be posting again anytime soon. We did have a great last day though. We spent the morning working on my abstract and packing things up before we found a wonderful geothermal area to relax in after our long week. This evening we drove into Reykjavik to say goodbye to Steina, Meagen’s colleague who helped get us into my field site, and enjoyed a real meal that wasn’t peanut butter and jelly. Overall we had a fantastic trip and I’m excited to work on my IS. I’m very sad to say goodbye to this beautiful country, but it’ll be good to be back home.