Student Symposium Abstracts - Geology

2012 Symposium Presenters 2012 Symposium Presenters #2

2012 Symposium Poster Presenters and Speakers
Poster presenters: Mike Barthelmes '13, Bill Rood '12, Luke Anderson '12, Ellen Shank '12, Julian Peota '12, Ni An '14, Nic Slater '12, Dan Cleary '12, Andrew Roers '12. Speakers: Professor Emily Walsh, Robin Drucker '12, Chelsea Nissen '12, Daniel Cleary '12, Professor Rhawn Denniston.

Tropical Sea Surface Temperatures Over the Last 120,000 Years

April 27, 2013

Sea surface temperature (SST) is one of the most important and fundamental components of Earth’s climate. Tropical SST determines the location of the Intertropical Convergence Zone where the northeast and southeast trade winds meet, and influences global moisture content, the strength of monsoons, and precipitation in the tropics.  Therefore, the importance of understanding the changes [...] Read More

A Stalagmite Record of Climate Variability from the Last Glacial Maximum Through Middle Holocene from Cape Range, Western Australia

April 27, 2013

Lots of research has been conducted on Australia’s late glacial (30,000-20,000 years ago), deglacial (20,000-10,000 years ago), and Holocene (the last 10,000 years) climate; however, few climate reconstructions exist for northwestern Australia due to a lack of data.  Drivers of climate variability over these time periods are important to understand because local climate adjusts to [...] Read More

Evolution of a Cretaceous Subduction Model: Insights from the Catalina Schist

April 27, 2013

The Catalina Schist crops out on Santa Catalina Island and underlies the southwestern California borderland, preserving a Cretaceous subduction zone environment. The Catalina Schist consists of amphibolite-facies rocks atop a suite of rocks metamorphosed at progressively lower temperatures with increasing depth. This inverted metamorphic sequence has been explained to be the result of tectonic juxtaposition [...] Read More

U/Th Dating of Cold Water Tufa Deposits from Kimberly Region of Australia

April 27, 2013

Paleoclimate records from Indonesia and the West Pacific Warm Pool (WPWP) reveal that changes in global and regional climate have altered the intensity and location of Indonesian-Australian Summer Monsoon (IASM) precipitation over glacial/interglacial cycles (Magee & Miller, 2004; Griffiths et al., 2009; Mohtadi et al., 2011). Understanding the magnitude and timing of monsoon variability in [...] Read More

A 4,000 Year Stalagmite Record of Extreme Rainfall Events in Tropical Western Australia

April 27, 2013

Global environmental change poses several risks, including the possibility of increased frequency and strength of severe weather events. Though extreme weather events are difficult to define precisely, they include, but are not restricted to, tropical cyclones (a.k.a. hurricanes and typhoons) and particularly intense rainfall episodes within summer monsoons. However, the main problem associated with present [...] Read More

Sea Level Rise and Fall Recorded in The Bahamas Caused by Glacial Events and the Future Impacts of Sea Level on World Population

April 27, 2013

The last several hundred thousand years have witnessed dramatic changes in sea level due to the growth and decay of the Greenland, Antarctic, and now-melted North American continental ice sheets. The last time sea level exceeded modern day levels was 120,000 years ago, at which time it was as much as 6-8 m above present. [...] Read More

Mud Layers and Oxygen Isotopic Ratios in Late Glacial Stalagmites from Coastal Western Australia

April 14, 2012

Mud layers trapped within stalagmites from caves in a variety of environmental settings have been interpreted as flood deposits.  Here we present a combined petrographic and isotopic analysis of one glacial-age stalagmite, AUS-118 from Cape Range, coastal Western Australia.  Stalagmite AUS-118 was thin sectioned and visually inspected and 121 mud layers were identified.  The distance [...] Read More

Paleoclimate Reconstruction in Portugal and the Iberian Margin

April 14, 2012

Paleoclimate reconstructions for Portugal and the Iberian margin have recently been conducted for the last glacial cycle with the main focus centered on both terrestrial and marine-based data. Portuguese stalagmites provide climatic information through oxygen and carbon isotopes in stalagmite calcite and can be dated using uranium-thorium techniques. One area of particular interest is the [...] Read More

Holocene Tropical Cyclone Activity in Northwestern Australia Recorded as Mud Layers in Stalagmites

April 14, 2012

Tropical cyclones (a.k.a. hurricanes and typhoons) are among the most devastating forms of extreme weather events in terms of loss of life and destruction of property.  Identifying long-term trends in tropical cyclone activity is crucial to understanding the mechanisms that drive variability in frequency and intensity.  Historical records of cyclone activity are high-resolution, but short-reaching, [...] Read More

Mud Layers in Stalagmites: A Proxy for Past Cyclone Activity

April 14, 2012

Our current understanding of trends in tropical cyclone activity in the Indo-Pacific is restricted by a limited historical record.  Mud layers deposited in stalagmites during flooding events in cave KNI-51 from tropical Western Australia appear to be a proxy for tropical cyclone activity in the region.  Aragonite stalagmites were precisely dated using U/Th mass spectrometry [...] Read More

Using Eclogites to Decode the Pressure/Temperature History of an Ultrahigh-pressure Metamorphic Zone, North Qaidam Mountains, China

April 14, 2012

An ultrahigh-pressure (UHP) metamorphic zone has been identified in the North Qaidam Mountains of China. Located on the northeastern edge of the Tibetan Plateau, the North Qaidam Mountains contain UHP eclogites, which indicate subduction of continental materials to > 90 km deep. UHP metamorphism occurred ~495 million years ago; the presence of an older ophiolite [...] Read More

Elemental Diffusion in Eclogite Garnets from the North Qaidam (U)HP Metamorphic Belt, China, and Its Implications for Thermobarometry

April 14, 2012

The northeastern region of the Tibetan plateau is composed of multiple terranes and tectonically altered zones, including the North Qaidam (ultra)high-pressure metamorphic belt (NQMB).  The NQMB is roughly 15 km wide, extends 350 km NW-SE, and contains well-exposed continental collision-type (ultra)high-pressure metamorphic rocks. Eclogites in the NQMB occur as blocks, boudins or layers within the [...] Read More

Understanding Millennial-scale Shifts in Australian Monsoon Variability Over the Past 40,000 Years Through Analysis of Stable Isotopes in Calcite Stalagmites

April 14, 2012

Approximately one third of the global population lives in the area affected by the Indo-Australian monsoon. Understanding the variability and dynamics of Australian monsoon rainfall, especially in response to global climate change, is of critical importance. Research in Borneo and Indonesia has demonstrated that the strength of the Indo-Australian monsoon is tied to millennial-scale climate [...] Read More

Monsters & Gigantism: Exploring Large Body Size

April 14, 2012

Large body size in movie monsters has inspired a new generation of scientists to explore the fact that real animals, both extinct and extant, have attained almost comparable sizes throughout geologic time. In this study I look at gigantism as preserved in the fossil record and at biologic problems arising from attaining a large size. [...] Read More

Characterizing Pyroxene Cooling Rate Using Reflectance Spectra

April 14, 2012

Pyroxenes are among the most common minerals in the inner solar system. The degree of order/ disorder in their crystal structure relates to the cooling history of the mineral. In pyroxenes, Fe2+ prefers the M2 cation site, and Mg prefers the M1 cation site in the crystallographic structure; the slower the pyroxene cools, the more [...] Read More

High-fluid Component in Some Recent Lavas from the Southern Cascades

April 14, 2012

We present U-Th and Sr isotopic data on young (Holocene) lavas from Lassen and Mt Shasta volcanic fields and surrounding areas.   Andesitic lavas from Shasta have 232Th/238U ratios of 2.6–2.7 and, similar to those reported previously, have activity ratios  (230Th/238U) of 1.01–1.03 close to secular equilibrium. A Holocene rhyodacite flow from Lassen has a 232Th/238U [...] Read More

Reconstructing Tropical Cyclone Frequency Using Mud Layers in Speleothems

April 11, 2011

Our ability to understand multi-decadal to centennial-scale trends in tropical cyclone activity is limited by the short duration of, and limitations in, historical records. In order to extend these records for tropical Western Australia, we have analyzed mud layers in stalagmite KNI-51-11 from the Kimberley region of north-central Australia that appear to be formed by [...] Read More

Combined Stalagmite and Limpet-Based Holocene Paleoclimate Reconstructions From Coastal Portugal

April 11, 2011

Few paleoclimate records preserve high-resolution information for the middle Holocene in (near) coastal Portugal, but this region contains many caves within a few kilometers of the coast.  In addition, shells of shallow marine invertebrates record sea surface conditions and some of these were harvested and preserved in archaeological middens. We attempted to develop a paleoclimate [...] Read More

Using Ultrahigh-Pressure Eclogites to Reconstruct the Tectonic Past of the North Qaidam Mountains, China

April 11, 2011

The North Qaidam Mountains on the northeastern edge of the Tibetan Plateau show evidence of ultrahigh-pressure (UHP) metamorphism, indicating subduction and exhumation of continental materials to > 90 km deep, within the mantle. The area most likely represents a suture zone, as an ophiolite is present, indicating the closing of an ocean. This ocean was [...] Read More

Using Epibiont Successional Patterns to Determine the Mode of Accumulation of Late Pleistocene Fossil Reefs

April 11, 2011

Coral colony orientation data obtained from Late Pleistocene reef coral assemblages preserved on Curaçao, Netherlands Antilles, Great Inagua and San Salvador Islands, Bahamas, indicates that the same gradient in hurricane frequency observed today also was present during Late Pleistocene time. We conduct an independent test of this hypothesis by examining the successional patterns exhibited by [...] Read More

Beach Dynamics of San Salvador

April 11, 2011

The San Salvador Island, Bahamas, is located within Hurricane Alley, causing the island to be passed by approximately 60 hurricanes in over a 100-year span.  The purpose of this project is to conduct a comparative multiyear study, from 1999 to 2010, of three beaches on San Salvador that experience different wave and wind regimes and [...] Read More

Monsoon Variability Preserved in Australian Stalagmites During the Early Holocene

April 11, 2011

Recent studies from Borneo and Indonesia have increased our understanding of the evolution of the Indonesian-Australian Summer Monsoon (InAuSM) system over the past 10,000 years (the Holocene epoch).  However, little is known about the InAuSM in Australia or at centennial time-scales. Here we present carbon and oxygen stable isotope data from two stalagmites collected from [...] Read More

Efficacy of the Curaçao Marine Park: A Pleistocene Perspective

April 8, 2011

As global climate change persists, anthropogenic impacts will continue to exacerbate current environmental degradation, particularly to coral reef ecosystems. To mitigate this critical situation, coral reef conservation efforts have focused on the development of effective marine protected areas (MPAs). However, successful ecological conservation and restoration require an understanding of previous community states – unaffected by [...] Read More

Pressure-Temperature Estimates of Eclogites in the North Qaidam Ultrahigh-Pressure Metamorphic Belt in China

April 8, 2011

The Tibetan plateau in Southwestern China is the result of multiple tectonic events. The region is composed of various terranes and tectonically altered zones, including the North Qaidam ultrahigh-pressure (UHP) metamorphic belt. The belt extends roughly 500 km NW–SE before being sinistrally offset by the Altyn Tagh fault and is found between the Qilian terrane [...] Read More

A Comparison of Analyses of Drilling Predation on Fossil Bivalves Using Different Sampling Methodologies: Bulk Sampling vs. Taxon-Specific Sampling and the Role of Collector Expertise

April 8, 2011

Taxon-specific sampling has been used in many studies of drilling gastropod predation and is particularly useful for rare taxa. Whether predation metrics from such samples are biased compared to bulk samples, the most widely accepted method of collection for studies of predation, requires testing. To test for bias, we compared analyses of predation in bulk [...] Read More

Tectonic History of the North Qaidam Ophiolite, Qinghai Province, China

April 6, 2011

The North Qaidam Ophiolite provides insight into the mechanisms that formed the rocks of the Tibetan Plateau before its uplift through the Cenozoic India-Eurasia collision. The ophiolite, juxtaposed and folded with an ultrahigh-pressure (UHP) terrane across the Luiliangshan Detachment Zone, separates the two major terranes in the region, the Qaidam and Qilian blocks. Two endmember [...] Read More

A Quantitative Analysis of Ceramic Thin Sections at Site 13LN323, Palisades-Dows State Preserve, Linn County, Iowa

April 6, 2011

Thin sections, prepared from sherds that were collected during recent excavations at site 13LN323, were analyzed by point counting compositional elements, which included natural inclusions (sand and silt), non-natural inclusions (temper) and matrix (clay). Dominant temper lithologies are granite, gabbro and basalt. Temper was preferentially selected by different cultures, with earlier cultures preferring granite, and [...] Read More

Fire History from Little Round Lake, Northwestern Wisconsin, USA

April 8, 2010

Fire history recorded in charcoal in lake sediments can be used to determine different climate conditions and vegetation, as well as fire frequency.  The observation of different charcoal morphotypes has been suggested to reflect fuel sources and burn conditions present at the time of the fire. I classified and counted charcoal from Little Round Lake, [...] Read More

Pleistocene Rapid Sea Level Change in Western Australia

April 6, 2010

Climate change affects sea level causing sea level fluctuations, which are correlated to glacial and interglacial periods. During glacial intervals water is stored as ice on the continents; therefore, sea level drops. When temperatures increase during interglacial periods, the melting ice sheets return the water to the ocean basins thereby raising sea level. These intervals [...] Read More

Trace Elemental Analysis of a North Australian Stalagmite

April 18, 2009

A 152 cm tall stalagmite (KIM1) was collected from the El Niño-Southern Oscillation (ENSO)-sensitive and monsoon-dominated Kimberly region of northwestern Australia. In order to better constrain the results of a previous a stable isotope study of KIM1, we conducted 173 trace elemental analyses at 1 cm intervals, corresponding to ~20 year resolution. Mg/Ca and Sr/Ca [...] Read More

Speciation in Fire Corals: What Constitutes a Species?

April 18, 2009

Two morphologies of Millepora, currently classified as separate species, exist off the coast of the Bahamas. Millepora complanata is found primarily in shallow waters, possessing wide, smooth branches whereas Millepora alcicornis is found primarily in deeper waters, possessing thinner, knobby branches. Upon discovery of colonies that contain intermediate morphologies, the question arose as to whether [...] Read More

Stability of Melt-rich channels in Earth’s Mantle: High Pressure and Temperature Experiments on Olivine, Chromite and MORB

April 29, 2008

Melt transport, the movement of molten rock through the Earth’s relatively solid outer shell, is important in many geological processes. Volcanism at subduction zones and hot spots and the formation of oceanic crust at mid-ocean ridges all involve melt transport. To increase our understanding of how melt moves from depth to Earth’s surface, we conducted [...] Read More

Big Bend National Park, Texas: an Educational Spring Break

April 29, 2008

In 2008, Cornell College’s Geology Club helped sponsor a trip for twelve students to Big Bend National Park in Texas. Big Bend hosts an array of impressive geologic features recording disparate events from Cretaceous deep-sea deposition to volcanic flows less then 30 million years old. This presentation will present a short history of the park’s [...] Read More

Paleobotanical Evident for “Pluvial” Intervals in the Western Pangean Tropics During the Early Permian

April 29, 2008

The transition from the Pennsylvanian to the Permian in the tropics of western Pangea was marked by a general trend toward increased temperature and decreased soil moisture, based on geophysical indicators, such as paleosol morphologies and oxygen isotopes. Vegetation tracked these changes and there is a 1:1 correspondence of species pools with climate proxies: floras [...] Read More

Sector Zoning and Age in Zircon Grains from the Western Gneiss Region, Norway

April 29, 2008

Zircon is a strong mineral capable of withstanding extreme geologic pressures and temperatures. It is able to retain geochemical signatures. which allow the timing of geologic events to be determined. The Western Gneiss Region of Norway is one of the largest exposed complexes of ultrahigh-pressure metamorphic rocks in the world. By determining the ages of [...] Read More

Scanning Electron Microscope Study of Zircon Grains in Gneisses and Pegmatites from the Western Gneiss Region

April 29, 2008

Metamorphic rocks, gneisses and pegmatites, from the Western Gneiss Region in southwestern Norway were analyzed to determine when the area was metamorphosed at ultrahigh pressures during the Caleonidonian orogeny. Cathodoluminescence images (CL) of zircon grains separated from the samples show older oscillatory-zoned igneous cores and younger metamorphic rims. The zircon samples were analyzed using a [...] Read More

Speciation in the Millepora Complex: What Constitutes a Species?

April 29, 2008

Fire coral from the genus Millepora are ubiquitous in tropical western Atlantic reefs. Two distinct morphologies of Millepora, currently classified as separate species, exist off the coast of the Bahamas. M. complanata have broad, smooth blades and prefer shallow waters whereas M. alcicornis have knobby branches and prefer deeper waters. After an intermediate morphology was [...] Read More

Skeletal Morphology of the Genus Millepora Displays Phenotypic Plasticity

April 29, 2008

The genus Millepora, commonly known as fire coral, is a calcareous hydrozoan common in tropical seas worldwide. In the western Atlantic, there exist two prominent morphologies that are presently being classified as separate species. Millepora alcicornis is defined by thin nodular branches; Millepora complanata has plate like, smooth blades. However, recent genetic data suggest that [...] Read More

Growth Histories of Late Pleistocene and Holocene Stalagmites From Cape Range, Western Australia

April 14, 2007

In moisture-limited environments, meteoric precipitation is the primary control of speleogenesis. We have investigated the growth histories of two stalagmites, 117 & 118, from C -126 Cave, Cape Range, Western Australia (22.1°S, 113.9°E) in order to reconstruct the timing of wet and dry periods during the Holocene and latest Pleistocene. Both stalagmites were dated by [...] Read More

Onshore/Offshore Trends in Preservation of the Cidaroid Subfamily Cidarinae

April 14, 2007

Echinoid tests are composed of a series of plates, interlocked with adjacent plates, and reinforced by soft tissue. Regular echinoids disintegrate in a generally predictable manner: spines disarticulate, followed by oral and aboral membranes, the lantern, and finally the corona which will break apart progressively. Cidaroid echinoids are characterized by having a small degree of [...] Read More

Fire-Cracked Rock Composition and Distribution in Palisades-Dows State Preserve, Linn County, Iowa

April 29, 2006

Palisades-Dows State Preserve was excavated by students at Cornell College and has produced sizeable lithic and ceramic assemblages. An in-depth analysis of the composition and distribution of the fire-cracked rock excavated at the site shows a relatively high amount of dolomite, gabbro, and chert and a relatively low amount of dolostone or limestone. Comparisons of [...] Read More

Hurricane-Controlled Beach Dynamics on Windward and Leeward Sides of San Salvador Island, Bahamas

April 29, 2006

Over an eight year period four beaches on San Salvador Island, Bahamas have been monitored with respect to their dynamic erosion and depositional processes. Beach profiles were made and evidence of two major hurricane events can be seen over the monitoring period. The prevailing easterly trade winds play a major role in the beach dynamics [...] Read More

Race and the Pullman Company, 1913- 1948

April 29, 2006

The Pullman Company shaped the traveling experience of generations of people in the US, starting in 1867 and continuing for 102 years. Soon after the Civil War, Pullman was one of the first industrial firms to hire former slaves. The Pullman Company was later the site of the first black labor union in the country [...] Read More

U-Th Chronologies of Stalagmites from Two Caves in Western Portugal

April 29, 2006

Stalagmites from two caves, Almonda Cave and Glory Hole Cave, located near Nazare in westcentral Portugal, are being investigated in order to reconstruct the region’ s paleoenvironmental history. Here we report our initial attempts to construct growth histories for these samples using U-Th mass spectrometry. Most stalagmites from Almonda Cave, one of the deepest and [...] Read More

Taphonomic Comparison of Modern and Pleistocene Coral Assemblages:

April 29, 2006

Taphonomic analyses of reef corals have been conducted in multiple reefal environments present in a great many locations including the Great Barrier Reef, Florida Keys, Bahamas, and Papua New Guinea. However, taphonomic research on modern and Pleistocene reefs of Western Australia has not been published. The study presented here examines taphonomic signatures retained by modern [...] Read More

An Ozark Stalagmite Record from the Penultimate Deglaciation

April 29, 2006

We present stable isotopic data from CS-04-5, a 54 cm-high, cylindrical calcite stalagmite from Cosmic Cavern, northwest Arkansas, which grew during the penultimate deglaciation (Termination 2). The chronology for CS-04-5 is based on six U-Th mass spectrometry dates, all of which fall in correct stratigraphic order (140.6±1.9, 138.5±2.6, 137.4±2.1, 136.0±2.5, 134.2±2.0, and 128.7±2.4 ka). Petrographic [...] Read More

Constituent Particle Analysis of Reefal Sediments from the Houtman-Abrolhos Islands, Western Australia

April 29, 2006

Constituent particle analyses have been applied to many different sedimentary environments, especially in the Bahamas and the Caribbean, but have rarely been used in analyzing sediments from Western Australia. This study compared sediment samples collected from modern and Pleistocene reef environments in the Houtman-Abrolhos Islands off the coast of Western Australia. The archipelago is located [...] Read More

Refining a High Resolution Climate Record from a Late Pleistocene New Zealand Speleothem: Stage 1 – Cross-Checking a Published Record

April 17, 2004

Isotopic analysis and U-Th dating of New Zealand speleothem MD3 has yielded a 31,000-year record of climate change published by John Hellstrom in 1998 (Hellstrom et al., 1998). This is a particularly important climate record because the Southern Hemisphere is mostly marine, and thus there are very few places to obtain high-resolution climate information. But [...] Read More

Observations on Microbial CO-Oxidation in Marine Systems: Dynamics of CO and Enrichment of CO Oxidizers

April 17, 2004

Oceans emit small amounts of carbon monoxide (CO) adding to the total CO load in the atmosphere. The hydroxyl radical is the primary sink for CO and other greenhouse gases. Therefore, the amount of CO in the atmosphere indirectly controls the residence time of greenhouse gases. Most CO in marine waters is derived from the [...] Read More

Genetic Analysis of Fire Coral

April 17, 2004

Coral are important components of underwater ecosystems and contribute to reef biodiversity. The Millepora genus (fire coral) is a hydrozoan represented predominately by two species prevalent on tropical western Atlantic reefs. Each species has distinct morphological features: M. complanata is broad, smooth, and blade-like while M. alcicornis is thin with knobby branches (Kaplan, 1982). However, [...] Read More