UC Geologists Introduce Colleagues to New Amphibian, New Tools to Study Volcanoes and More

From a newly discovered, and armored, amphibian to new tools for understanding volcanoes, to dating hillside erosion, geologists from the University of Cincinnati’s McMicken College of Arts & Sciences fill the agenda at the upcoming Geological Society of America (GSA) annual meeting Nov. 2-5.

UC geologists will present 27 papers and posters among the 170 symposia and other sessions scheduled at the conference. More than 6,000 geoscientists will gather for “Geoscience Horizons,” the 115th annual GSA conference, which meets at Washington State Convention and Trade Center in Seattle.

Beyond the variety of research topics presented, University of Cincinnati geologists demonstrate emerging trends in how science is conducted on a dynamic campus today. Among the presentations, UC demonstrates a commitment to:

• undergraduate research with a student listed as co-author on one presentation,
• interdisciplinary collaboration with a session co-authored by geologists and archaeologists, and
• global collaboration with projects between UC and scientists in Austria, New Zealand and England.

A sampling of the presentations includes:

Civil War and computers help hillside history analysis
When the Confederate soldiers built defensive earthworks around Charleston, South Carolina, they had little idea they were setting the groundwork for a geologic experiment. Because the age and original shape of these artificial hills is well documented, they provide a good laboratory for the study of hillside erosion. Reuben G. Bullard Jr. of the University of Cincinnati geology department reports that his studies show that the earthworks provide information on both the rate and pattern of erosion. Bullard’s work has been assisted by an updated version of SLOPEAGE, a computer program for dating hillsides, developed by UC geologist David Nash.

New model for hillside erosion
What goes up must come down – that is the basic law of erosion. But, how fast do landscapes erode? And what factors affect the rate of erosion? The answers can help us provide accurate dating of hillsides. University of Cincinnati geologist David Nash questions the conventional assumption that steepness of slope is the only factor. The size of the slope, Nash said, is very important. In the area around Jenny Lake in Teton National Park, Wyoming, Nash found a number of scarps (landslides) of known age. The steepness of the slope was only a partial indicator of the age of these erosion incidents, but factoring in both steepness and size resulted in a very accurate dating.

Trace elements open a window to ancient environments
During the Pennsylvanian Period (320 million years to 286 million years ago), when many U.S. coal beds were deposited, sea level rose and fell repeatedly, creating a transition from swamp to fresh water to seawater and back. These transitions, caused by a mechanism not fully understood, are recorded in the rocks as characteristic features known as cyclothems. UC geologists Thomas Algeo and Barry Maynard have analyzed trace elements in these formations and discovered that their abundance is remarkable, not only in comparison to ancient deposits, but to modern organic-rich environments.  In particular, Algeo and Maynard found two distinct patterns of trace-element abundance that could provide a picture of an environment in which sulfur and oxygen were more or less abundant during the “Coal Age,” and this could give us a clue to what caused sea levels to rise and fall.

A new tool for studying volcanoes
A geologist trying to determine the origin of a volcanic rock such as basalt needs accurate chemical tools, or the evidence will yield faulty conclusions. Sometimes, for example, lava pours straight from pools deep in the earth, and forms minerals entirely from within its flow. In other circumstances, lava flows pick up contaminants from the strata it flows through. University of Cincinnati geochemist Attila Kilinc, working with post-doctoral researcher Tammie Gerke, discovered that a widely accepted chemical benchmark has more limited use than believed. Kilinc and Gerke analyzed basalts with high-alkaline content from China and Antarctica, and have generated a new equation for analyzing a wide variety of basalts. By adopting the new technique, geologists may develop a clearer picture of how volcanoes – and the rocks they create – form.

Austrian Alps yield proof of ancient volcanoes
University of Cincinnati geologist Warren Huff has been working with colleagues for several decades to collect and analyze deposits from ancient volcanoes. The deposits, known as K-bentonites, were formed after massive volcanism in the Ordovician and Silurian periods roughly 450 million to 400 million years ago. By tracking these deposits across continents, Huff and his collaborators can reconstruct how the ancient land masses moved. Huff will present his latest analysis, of volcanic evidence from Austria’s Alps. Working with scientists from the Geological Survey of Austria, Huff found that, although somewhat altered by 450 million years of geologic effects, a volcanic fingerprint still remains clear, and can be matched across Europe. “The abundant presence of these horizons in the Carnic Alps is similar to those in the British Isles, Sweden, Canada and North America and documents widespread volcanism related to the closing of the ancient Iapetus Ocean and northward drifting of pieces from the northern margin of the Gondwana super-continent,” Huff said.

Black shales tell a green tale
During the Devonian Period, 417 to 354 million years ago, thick beds of rock known as black shales were deposited. University of Cincinnati geologist Thomas Algeo noted that black shales are rich in carbon and phosphorous – elements associated with living things. How these elements, particularly phosphorous, got into the rock can tell us a lot about ancient conditions. Algeo discounted a massive change in the percentage of phosphorous deposited, as well as upwelling from marine sources. The evidence points to a new invader on the Devonian landscape – plants. The phosphorous found in these rocks is probably the result of chemical weathering, a mechanism that would have sped up as plants became more common on dry land and bolstered the creation of organic soil.

Tales of a Kansas sea preserved in stone
A layer of organic-rich rock in eastern Kansas tells tales of a vast seaway that once ran through the middle of North America around 300 million years ago. University of Cincinnati geologist Thomas Algeo, along with James Hower of the University of Kentucky, examined this layer in great detail, mapping chemical and physical changes, centimeter by centimeter, through nearly two feet of rock – what Algeo and Hower describe as “an archive of high-frequency climato-environmental variation.” Throughout the sequence represented in these rocks, land-originated organic material dropped off precipitously while chemical analysis indicates a rise and then fall in water depth. In general, the sequence suggests a transition from warm and humid conditions favoring development of coal swamps to cooler and possibly dryer conditions. These findings document the scale of contemporaneous changes in climate and land vegetation that occurred between glacial and interglacial stages of the Late Pennsylvanian Period.

Who Ate Whom? Decoding fossilized food webs
Throughout the 1970s and 1980s, paleontologists took a first look at recreating predator-prey relationships in fossilized environments by building “paleo-food webs.” What could have been a useful method for bringing fossil communities to life was abandoned because the analytical tools available then didn’t have enough precision to generate meaningful principles about these food webs. A team of paleontologists from several U.S. and British institutions including the University of Cincinnati have taken a close look at food webs from the Cambrian, Mississippian and Eocene rocks, three intervals that sit far apart in geological time. “Despite the very different temporal, spatial and ecological contexts of these three paleo-food webs, there appear to be no intractable problems in reconstructing complex webs for carefully chosen and well-documented fossil assemblages,” said UC paleontologist Arnold Miller. This research opens the possibility for a better understanding of whether and how food web structure evolved over time, Miller said.

New Zealand glaciers take global temperature

In the quest to better understand global warming and other large-scale climatic changes, glaciers can provide a lot of information – if they can be read with accuracy. University of Cincinnati geologist Thomas Lowell, working with George Denton of the University of Maine, report that six glaciers in New Zealand record climatic change with substantial accuracy. These glaciers have been in retreat since the end of the 1800s, but were spreading in the 1700s and early 1800s during a period known as the “Little Ice Age.” Lowell and Denton called upon data from a variety of sources, including historical accounts and lichen growth patterns to indicate that all six glaciers reflect global climate changes in common. “All began to retreat at the same time within the resolution of the dating techniques,” Lowell said. “The climate signals should be of the magnitude of the Little Ice Age or larger to overcome the influence of local conditions.”

A new twist on glacial deposits
The landscape of Ohio is a record of repeated assaults by glaciers during the last Ice Age. Although the glaciers retreated 100,000 years ago, geologists are still sorting out what today’s landscape tells us about that frigid time. In 1882, a geologist described a peculiar glacial deposit which he called an “interlobate moraine.” Geologists have believed that, as two arms of a glacier retreated, material piled up between them, creating this signature pattern. Using field mapping, aerial photography and digital models, Alexander Stewart and Thomas Lowell of the University of Cincinnati geology department, arrived at a new interpretation. Stewart and Lowell found that the interlobate deposits were asymmetrical, with stratified materials on one side and unstratifed materials on the other. Since this pattern appears in several areas, it may imply that during glacial retreat one lobe stagnated whereas the other remained active.

Where did Albanian millstones come from?
A collaboration among anthropologists, classical archaeologists and geologists at the University of Cincinnati is using geochemical analysis to trace the origins of ancient millstones found in a prehistoric settlement in Albania. The millstones, of volcanic origin, were collected as part of a surface survey from the Greek colony of Apollonia, in central Albania. Apollonia, founded in the 6th and 7th centuries B.C., is located in an area without volcanic rocks. The interdisciplinary team believes the millstones originated in Italy and arrived in Albania through trade. A chemical profile of the millstones has been developed, and the team is comparing that profile to chemical signatures of Italian and Greek volcanoes. The effort is part of the University of Cincinnati-based Mallakastra Regional Archaeological Project, a multi-disciplinary archaeological expedition organized in 1996 to investigate the history of settlement and land use in central Albania.

Soiled communication: Effect of trees on early ocean life
The Middle to Late Devonian Period, around 360 million years ago, saw major changes in life on land, including the evolution of trees and seed plants and the appearance of multi-storied forests. At the same time, there was a crisis in the sea that decimated tropical sea-floor environments, especially reef communities. The connections between these terrestrial and marine events are poorly understood, but a key may lie in the role of soils as a link between the two environments and the role of land plants in affecting this link, according to University of Cincinnati geologist Thomas Algeo and Stephen Scheckler of Virginia Polytechnic Institute. Algeo notes that as plants took over the land they grew both taller and deeper as their roots dug firm foundations and plants moved out of moist lowlands as seed-bearing capabilities improved. This led to the creation of organic-rich soils from which leached nutrients were swept by rivers into the sea, dramatically disrupting the marine environment. “The role of soils as a geochemical interface between the terrestrial and marine biospheres has received insufficient attention, “ Algeo said, “yet weathering rates during soil formation are a fundamental control on bionutrient availability and, hence, an important influence on patterns of evolution and extinction in marine ecosystems.”

New armored fossil amphibian identified
For several years, William Garcia has been investigating a deposit of fossils located in Kentucky and dating from the Mississippian Period, around 325 million years ago. The Hancock County site has yielded a variety of fish and amphibians, including a previously unknown amphibian. The newly identified creature is represented by a mostly complete skeleton with evidence that this amphibian – unlike smooth-skinned frogs and salamanders – was armored with scaly plates embedded in its skin. The likely reason? Garcia notes that his amphibian was aquatic and swam alongside carnivorous fish reaching 16 feet in length.

Bad day at Jurassic Park
The Mother’s Day Site, located in south-central Montana’s upper Jurassic rocks, preserves the remains of a herd of young sauropod dinosaurs. Evidence indicates that all of the juvenile to sub-adult dinosaurs were killed at one time. While previous research suggested that the dinosaurs became stuck in a muddy flat, Timothy Myers of the University of Cincinnati geology department has found new clues that a strong current deposited the remains. Myers said his review of the fossilized material shows evidence of this current, and also that the water was sweeping freshly killed animals, rather than gathering up loose bones.

Does the wire read what the eye sees?
There is a big problem involved in studying layers of rock: The layers under study are often buried by megatons of rock. Geologists use a variety of tools to “see” into these buried layers, including a technique known as “wireline" logs, which are produced by lowering a bundle of instruments into a hole created by drilling, a cheaper and quicker alternative to extracting core. But, how accurate are these? Austin Hendy of the University of Cincinnati, working with Peter Kamp of the University of Waikato, New Zealand, looked at the record of sea-level changes by comparing wireline log data to a core of rock pulled from a drill hole. By comparing fossils found in the core sample to modern sea life, they provided an independent and detailed record of rapidly changing sea level through 1 million years of geologic time.  This study showed that wireline logs can indeed provide a good look at subsurface strata in the absence of drilling cores and enable geologists on the surface to read the buried record of sea-level changes with confidence.

Looking underground to look further afield
The Ordovician rocks of southwestern Ohio and northern Kentucky are so abundant and so abundantly exposed because of the area’s hilly terrain, that few researchers look beyond readily accessible exposures. But Brian Kirchner and Carlton Brett of the University of Cincinnati geology department were up against a rock wall in their investigation of ancient environments. The surface exposures displayed cycles, from one-half meter to three meters thick, between different types of rock, but surface exposures do not give a full picture of the extent of these cycles over a large region. Kirchner and Brett used a new set of cores drilled throughout the area, in addition to surface surveys, to map the cycles over tens of kilometers. They found that the addition of subsurface samples gives a clearer picture of the processes at work. It appears that – contrary to previous theories that falling sea level generated the cycles – minor periods of rising sea levels are probably the driver.

Ohio universities make science work for public good
Kyle Ward, an undergraduate student at the University of Cincinnati, is a pioneer in an Ohio project known as SOARS to put science to work in the public interest. SOARS (Scientific Outreach and Applications using Remote Sensing) recruits undergraduate and graduate students pursuing degrees in remote sensing, Geographic Information Systems (GIS) and related disciplines. SOARS was developed by OhioView, a grassroots organization formed to make satellite data more accessible to educators, industry and the public. Ward was part of a team drawing from many Ohio universities researching the condition of the Cuyahoga River over the past 14 years. As part of their most recent work program, GIS and satellite mapping is being utilized to create tributary-based watershed maps that are intended for presentation and distribution to local officials and public interest groups.

Clues from Smuggler’s Cove: How accurate are paleontology’s models?
Paleontologists often make assumptions about ancient environments by looking at collections of many fossils found at a single site. They believe their conclusions are accurate by comparing ancient assemblages to modern environments in which animal remains are on their way to becoming fossils. But how accurate is this comparison? University of Cincinnati paleontologists note that modern sea-floor shell beds often contain materials that – while not quite fossilized – are many thousands of years old. To test the accuracy of this ancient-to-modern model, the UC paleontologists compared a detailed inventory of seabed remains at Smuggler’s Cove, Virgin Islands, in 1980 and again in 2002. They discovered that, while the model held up fairly well, it was possible to map significant changes in snail populations over the 22-year period. “This transition suggests that there was a change in the physical or ecological dynamics of Smuggler’s Cove during the period between the two studies,” said graduate student Chad Ferguson. It is possible, then, that fossilized assemblages may not be telling the whole story about how dynamic environments are through time.