Adventures in Fillmore

June 3rd, 2012

FILLMORE, UTAH – [Guest bloggers Matt Peppers and Will Cary]

As Dr. Wilson so kindly stated in his last blog post, the Utah group arrived safely at Salt Lake City International Airport on Saturday, June 2. After stopping briefly at a Target to get various essentials, we finished our two-hour drive at Fillmore (see here for how the drive went), the town we will reside in for the next two weeks. We are staying at a KOA Kampsite in some kozy little kabins. After getting acquainted with the campsite layout, we explored some of the finer cuisine options, finally settling on Larry’s Drive-In Diner across the road. Will tried a marshmallow milkshake that gave him enough sugar to power through the jet lag associated with the time zone change. After a filling meal, the group headed back to the campsite for a quick group meeting to go over the schedule for Sunday, which promised to be an orientation day to the Black Rock Desert and what we could expect. Following the meeting, everyone felt the effects of travel and promptly retired to their respective cabins for the evening.

Dr. Judge lays out the maps for our field site.

The next morning, the group met at 9:30 to pack lunches for the day followed by an overview of equipment and safety precautions that we would need for our fieldwork. With backpacks set up, we gathered as much water as we could carry and set out to our first meeting with the Black Rock Desert. We drove directly west out of Fillmore and, although we couldn’t get onto it, saw Ice Springs, our future field site. We drove around the flow front boundaries and were impressed by how distinct and steep the boundaries actually were. Because today was an orientation day, we set out to find some lava tubes in the Tabernacle Hill lava field. Although we were unsuccessful in locating them, we had some good experience using the GPS units. In addition, we spent a lot of time looking at pressure ridges in the lava field, which adds additional complexity to some students’ projects.

Admitting defeat in finding the lava tubes (and questioning the signage that lead us to that area), we drove on to White Mountain, a hulking mass of gypsum sand a few minutes away. Looking for a place to get out of the 93° heat to eat our lunches, we headed to the one tree we had seen in the entire trip. Stepping out of the car almost had us believing we were in the Bahamas, and the white sand proved a pleasant place to sit. As we moved under the shade of the tree, two small owls flew out from its branches. Waiting cautiously in the leaves above us were three more owls, who seemed upset that we interrupted their lunch with our lunch (3 dead mice taunted them from next to where we were sitting).

The glare of someone who's had his lunch interrupted.

Imagining we are in the Bahamas.

After getting back into the car, we asked Dr. Judge and Dr. Pollock what our next stop would be. Getting only a, “Classified” as a response, all we could do is bounce around in the back of the car down a dusty road. We were pleasantly surprised when the trip ended at a natural hot spring. We eagerly climbed out of the car and jumped in.

Nature's gift.

We continued our first full day by taking a quick stop back at the campsite for a change into dry clothes before heading to meet Dr. Wilson’s, aunt, Ms. Sylvia Huntsman. She graciously welcomed us into her house where we played with her two dogs, Zeke and Bogey and ate delicious apple cobbler. When eyes started to droop from too much time sitting in a comfortable air-conditioned house, we excused ourselves to go eat more food. The fine cuisine of Fillmore proved itself once again at the “Garden of Eat’n.”

The first day ended with a final meeting back at the campsite to set a schedule for Monday (the 7 am departure time was a harsh return to reality) and a beautiful sunset.

Wooster’s Fossil of the Week: A trilobite (Middle Cambrian of Utah)

August 14th, 2011

I’ve avoided having a trilobite as Fossil of the Week because it seems like such a cliché. Everyone knows trilobites, and they are the most common “favorite fossil” (invertebrate, anyway). Plus our best trilobite (seen above) is the most familiar trilobite of all: Elrathia kingii (Meek, 1870). One professional collector — just one guy — said that in 20 years he sold 1.5 million of these.

Still, trilobites are cool. They virtually define the Paleozoic Era, appearing in the Early Cambrian and leaving the stage (with so many others) in the latest Permian. They were arthropods, sharing this very large phylum with insects, spiders, crabs and centipedes. The name “trilobite” means “three lobes” referring to the axial lobe (running down the center along the length of the animal) and the two pleural lobes, one on each side. They  also have three parts the other way: a head, thorax and pygidium (the tail end).

Elrathia kingii is a ptychopariid trilobite found in extraordinary numbers in Middle Cambrian dark shales and limestones. There is a geological story here, two of them, in fact. One reason they are so common is that their populations were commonly buried by sediment stirred up in massive storms (Brett et al., 2009). They are among the only fossils found in organic-rich dark sediments because they lived in the harsh “exaerobic zone” at the very minimum of oxygen needed for animal life (Gaines and Droser, 2003). They apparently were the first large invertebrates to exploit this marginal environment.
Elrathia kingii gives us the opportunity to meet a pioneering American paleontologist: Fielding Bradford Meek (1817-1876). He originally described this species in 1870, calling it Conocoryphe kingii (see above). Paleontologists are quite familiar with the name “Meek” following a fossil species because he described hundreds of them. Meek was a native of Madison, Indiana, a place where Ordovician fossils are abundant and easily collected. He was apparently an unsuccessful businessman so he jumped at a chance in 1848 to work for the U.S. government surveying the geology of Iowa. Meek was good at this job and soon was working with James Hall in New York, the country’s premier paleontologist. Meek was eventually based in Washington, D.C., with the United States geological and geographical surveys. After many accomplishments in government service, he died of tuberculosis in 1876 (White, 1896).

Fielding Bradford Meek

References:

Brett C.E., Allison P.A., DeSantis M.K., Liddell W.D. and Kramer A. 2009. Sequence stratigraphy, cyclic facies, and lagerstätten in the Middle Cambrian Wheeler and Marjum Formations, Great Basin, Utah. Palaeogeography, Palaeoclimatology, Palaeoecology 277: 9-33.

Gaines, R.R. and Droser, M.L. 2003. Paleoecology of the familiar trilobite Elrathia kingii: An early exaerobic zone inhabitant. Geology 31: 941–944.

White, C.A. 1896. Memoir of Fielding Bradford Meek, 1817-1876. Biographical Memoirs, National Academy of Sciences, p. 75-91.

Wooster’s Fossil of the Week: Oyster balls! (Middle Jurassic of Utah)

April 17th, 2011

The technical term is ostreolith, but “oyster ball” is much more descriptive. These fossils are found by the thousands in the Carmel Formation (Middle Jurassic) in southwestern Utah. As far as I know, this is the only place they’ve ever been found. Colin Ozanne (’96) worked on these ostreoliths as part of his Independent Study project, and the results of our work were published in a 1998 issue of Palaios. Colin now, by the way, is an Engineer Trial Attorney for the US Army Corps of Engineers in Buffalo, New York.

Ostreoliths are “circumrotatory accumulations” of the little oyster Liostrea strigilecula. The most common form began with a clam shell fragment as a nucleus. Oyster larvae recruited on the top shell surface and grew in the normal way. A current, though, flipped the shell over, exposing the underside that was in turn encrusted by more oyster larvae. These grew into larger oysters until, again, the shell flipped back over. A new generation of oysters then encrusted the older layer. The shell then overturned again and … you get the idea. Some ostreoliths grew this way to almost a quarter meter in diameter. The cup-shaped left valve of Liostrea was an essential feature for ostreolith development. A typical flat oyster would not build the necessary depth with each layer.

Polished section through the middle of an ostreolith showing the curved nucleus shell and calcite-filled bivalve borings.

Closer view of oysters on the surface of an ostreolith. Note how juvenile oysters are clustered within the left valves of an older generation.

Several sclerobionts (hard substrate dwellers) grew with the oysters on the ostreoliths, including the bivalve Plicatula, disciniscid brachiopods and cyclostome bryozoans. Mytilid bivalves also drilled holes (called Gastrochaenolites) in the oyster skeletons to form cavities for their filter feeding.

Ostreoliths, strange and unique as they are, tell us a lot about the depositional environment of the Carmel Formation. The sediments accumulated in these horizons under fairly high energy with periodic storm disturbances. The mytilid borings trapped ooids during formation of the ostreoliths, showing that this characteristic carbonate sediment was more common in the environment than indicated by the rocks alone.

Carmel Formation exposed at Gunlock Reservoir near St. George, Utah.

Regardless of their scientific value, though, oyster balls certainly start good conversations!

Wooster’s Fossil of the Week: A brittle star trace fossil from the Jurassic of Utah

February 13th, 2011

This week we have a trace fossil that looks almost exactly like the animal that made it. A trace fossil is evidence of organism activity recorded in the rock record. The photograph above shows one of my favorite specimens: Asteriacites lumbricalis von Schlotheim 1820 from the Middle Jurassic (Bathonian) Carmel Formation in southwestern Utah. I collected it while doing fieldwork with Wooster student Steve Smail too long ago for either of us to mention.

This fossil was made when a brittle star (ophiuroid) burrowed into carbonate sediment to either hide from predators or to look for a bit of food. Brittle stars are echinoderms that appeared in the Ordovician and are still very much alive today (see below). This Jurassic trace was formed when a brittle star essentially vibrated its way down into the loose sediment in a manner many of their descendants do today. The result is what appears to be an impression of the body (an external mold) but is actually formed by action of the animal.

Green Brittle Star (Ophiarachna incrassata) courtesy of Neil at en.wikipedia.

The trace fossil Asteriacites is far more common in the rock record than the brittle stars and seastars that made it. These traces thus often indicate the occurrence of organisms in critical intervals where they would otherwise be unknown. For example, Asteriacites lumbricalis is found in Lower Triassic rocks showing that brittle stars were part of the recovery fauna after the Permo-Triassic Mass Extinction (see, for a Wooster example, Wilson & Rigby, 2000).

Stony bryozoans get their day

August 1st, 2010

Trepostome ("stony") bryozoan on a carbonate hardground from the Kanosh Formation (Ordovician, Whiterockian) of west-central Utah.

KIEL, GERMANY–The first day of the International Bryozoology Association meeting is traditionally devoted to workshops where participants can listen to experts on a particular group, technique or idea and then ask questions, work out exercises, or study specimens. I went to the workshop on a group of extinct bryozoans called trepostomes. The Order Trepostomata usually produced thick skeletons of the mineral calcite so they are commonly known as “stony bryozoans”. They lived from the Ordovician into the Triassic, and then disappeared forever. They are a difficult group to work with because their diagnostic features are internal and microscopic (thus requiring thin-sections or acetate peels to identify) and the number of important defining characters is still debated. I went to this workshop because Ohio can be considered the Trepostome Capital of the World with its abundant and diverse varieties found in the Ordovician of the Cincinnati area. Any Wooster geology student who has taken the Invertebrate Paleontology course will remember the buckets of these fossils we’ve collected over the years on field trips.

Wooster played a small role in this workshop, to my delight. One of the interesting and somewhat odd trepostome bryozoan types is found in the Ordovician (Whiterockian) at a place called Fossil Mountain in the western desert of Utah. A generation of Wooster Independent Study students worked here with me studying carbonate hardgrounds and the fossils associated with them. We collected many examples of a strange bryozoan we called “Trepostome Species A” because we could not identify it. Later Andrej Ernst, Paul Taylor and I described it as a new genus: Kanoshopora. It is still odd with its variable walls and colony forms. This meeting may have stirred some interest in pursuing its functional morphology (essentially how it lived) and evolutionary placement. A nice contribution from those days in the late 20th Century when we walked up and down the sunny slopes of Fossil Mountain trying to sort it all out.

Longitudinal thin-section view of Kanoshopora droserae showing its complex zooecial walls.

Fossil Mountain, west-central Utah -- the scene of much Wooster geology Independent Study fieldwork in the 1980s and 1990s, and the home of many of the oldest and strangest trepostome bryozoans.

A view of the Wasatch Mountains from above

July 18th, 2010

Looking west over the Wasatch Mountains into the Salt Lake Valley of Utah. Note the beautiful syncline in the center of the image. Flying across the western United States is such a treat for a geologist. These are the kind of structures the Wooster Utah team is enjoying this summer.

The Bonneville Flood and where it began

July 17th, 2010

DOWNEY, IDAHO–Lake Bonneville has been one of the geological themes of my short visit to northern Utah this summer. The remnant wave-cut platforms of its shorelines dominate the geomorphology of the Logan area, and the lake sediments are the basis for the rich soils of the Cache Valley. Today my parents and I visited Red Rock Pass in southern Idaho where this massive lake breached a weak area of limestones and shales 14,500 years ago and then catastrophically flooded the land to the north. The Bonneville Flood was not as large as the Missoula Floods of geological legend, but it left a very similar record of scoured land, scattered boulders, huge waterfalls, and thick gravel bars.

Red Rock Pass near Downey, Idaho. The rocky hill in the center was part of the dam of sedimentary rocks which gave way 14,500 years ago and released the catastrophic Bonneville Flood.

View north from the dam area looking down one of the flood channels. On the left is a rocky outcrop of the original dam. On the right along the side of the channel is a gravel bar running parallel to the current direction.

Sure this is a geology blog, but these wildflowers …

July 16th, 2010

… are fantastic!

Blue flax, Indian Paintbrush and other wildflowers near Tony Grove Lake, Cache County, Utah.

Geologists are natural historians, so of course anything natural (or historical!) fascinates us. Stephanie Jarvis showed us some flowers (and mushrooms) in Alaska this summer. Last year we looked at acacia trees in Israel. We’ve even delighted in moss, flowers and wild strawberries in Estonia. The wildflowers this week in Logan Canyon, northern Utah, are extraordinary. In keeping with tradition, I want to share a few.

Colorado Columbine (left); Scarlet Gilia (right).

Blue Flax (left); Sticky Geraniums (right).

Floret of a Giant Gentian (left); florets of the Elephant's Head Figwort (right).

Geysers, Mountains, and Dinosaurs…OH MY! (Subtitle: This Summer is Stromato-Tight)

July 16th, 2010

Guest Blogger: Elizabeth Deering

This summer I have been given many amazing opportunities starting with my employment at the Wyoming Dinosaur Center in Thermopolis, Wyoming. Since late May I have been working with 7 other summer staff members giving tours, working in the prep-lab, and excavating Camarasaurus and Allosaurus bones. Excavating bones is a lot different than what you see in the movies and its definitely not as easy, but it is still a lot of fun. We use dustpans, brooms, oyster knifes, and occasionally hammers and chisels to excavate the bones, but before we can remove them we have to take many measurements and GPS coordinates so we can map the bones for further study. This summer we have found many vertebrae, teeth, and even some cranial material! One of the coolest finds was discovered on accident when a staff member broke an Allosaurus humerus in half with a chisel. The inside of the humerus was hollow and had been replaced with an unidentified mineral, making it look like a geode. It was a very unique find for the center.

Two summer staff members and myself working on excavating a Camarasaurus at the BS (Beside Sauropod) quarry at the Wyoming Dinosaur Center.

Two summer staff members and myself working on excavating a Camarasaurus at the BS (Beside Sauropod) quarry at the Wyoming Dinosaur Center.

Thermopolis is only a few hours from both Yellowstone National Park and Grand Teton National Park, so my roommates and I have taken advantage of our location and made a few weekend trips to both parks. They are both amazing! Yellowstone is unique because of the drastic changes in landscape that you encounter while driving through the park. In places it can be very wooded and have an alpine feeling, while in other places it can be very desolate and have lots of geothermal activity. Personally, I liked the more desolate landscape of Yellowstone. It was amazing to see things like geysers, paint-pots, and mineral springs. The Tetons were also incredible. They are younger mountains, so they have less erosion and are more jagged than other mountains. There is absolutely breathtaking scenery in the Tetons and many fun activities as well. If you ever find yourself in Wyoming I recommend seeing both parks.

Fountain Paint-Pot, Yellowstone National Park, Wyoming.

Fountain Paint-Pot, Yellowstone National Park, Wyoming.

Grand Teton National Park, Wyoming.

Grand Teton National Park, Wyoming.

Right now I am in Ephraim, Utah, with Dr. Judge and Jesse Davenport working on my Senior I.S. on stromatolites in the Green River Formation. This past week we have worked hard in the hot sun collecting samples and making strat columns. We have gathered a lot of great samples and lots of important information to include in my paper, but we have had a lot of fun too! I am here in Utah until Tuesday and then I fly back to Thermopolis to finish up the summer.

A Great Unconformity

July 16th, 2010

I almost forgot our quick side trip at the end of the day. With the Green River Formation behind us (literally, in this photo), we turned to view a fantastic example of an angular unconformity here in central Utah. Although there are several significant unconformities in the area, this unconformity is probably my favorite, because it shows paleotopography as you follow it regionally from west to east.

The photo above shows the unconformity that places the Paleogene Colton Formation on top of the vertical Jurassic Twist Gulch Formation.

The photo above shows the unconformity that places the Paleogene Colton Formation on top of the vertical Jurassic Twist Gulch Formation.

« Prev - Next »