Physical Sciences and Mathematics Commons^™

Computer-Assisted Graphic Correlation Of Ordovician Conodonts And Graptolites From The Argentine Precordillera And Western Newfoundland Using Constrained Optimization (Conop9), Andrea Marie Bryan

Honors Theses

The correlation of rock units is the foundation of geological research. Correlation is the process of proving two geologic events are time equivalent. Most importantly, it is used to establish time boundaries in the geologic time scale. This paper uses computer assisted graphic correlation (CONOP9) to correlate the ages of graptolites and conodonts from the Ordovician found in rocks from the continent Laurentia, and arranges them in a composite range chart. These two organisms lived in different environments and, therefore, are found in different biofacies. The Argentine Precordillera and the western Newfoundland region are places where these two fossils co-exist …

Nitrate Contaminant Tracing In Surface And Groundwater In The Great Miami River Watershed: Environmental Isotope Approach, Rachel Kristine Buzeta

Honors Theses

The global population has increased exponentially causing several challenges surrounding sustainability, including greater food production needs. To meet these demands and boost agricultural productivity, more efficient practices and fertilizers are used. Synthetic fertilizers and other nutrient sources have resulted in water quality degradation and pollution. Much of the Great Miami River Watershed’s streams and aquifers in southwestern Ohio are affected by nitrate contaminants originating from anthropogenic sources including synthetic and organic fertilizer used for agriculture, human wastes (domestic, industrial, and municipal wastes), and urbanization. High nitrate concentrations cause ecological disturbances across all trophic levels. Nitrate levels greater than 10 mg/L …

Revising The Geological Time Scale: A Conop9 Graptolite Composite From The Middle Ordovician Rocks Of Newfoundland, Katherine Michel

Honors Theses

The Geological Time Scale is a fundamental tool for geoscientists that is revised and republished every eight years. It is a representation of the geologic record - a system composed of radioisotope dates interpolated into fossil successions that can be used to correlate rocks. The current Geologic Time Scale for the Ordovician Period (GTS 2012) is composed of a sequence of species ranges from a group of fossils called graptolites with interpolated radiometric dates. Building a global geologic time scale requires correlating between different biofacies.

In this thesis I will attempt to combine stratigraphic range data from different kinds of …

Global And Regional Chitinozoan Biodiversity Dynamics In The Ordovician: Relationships To Sea-Level, Carbon Cycling And Tectonics, Jordan Watson

Honors Theses

Fossil species provide extensive information about the past history of life on Earth. This thesis focuses on the global and regional biodiversity dynamics of the extinct fossil group Chitinozoa, and analyzes the impact and influences of sea-level, global carbon cycling and tectonics on their biodiversity. Biodiversity curves were generated from three different paleo-continents, Laurentia, Baltica, and Gondwana using the automated graphic correlation computer program CONOP9. Traditional methods of biodiversity analysis count fossil taxa in individual intervals of geologic time. The results of these methods are highly dependent upon interval length and the relationship of taxon range to interval boundaries. CONOP9 …

Chitinozoan Biodiversity In The Ordovician Of Gondwana: An Interval-Free Approach Using The Quantitative Stratigraphic Correlation Program Conop9, Rachel Sales

Honors Theses

The purpose of this study is to examine the biodiversity patterns of a group of fossil organisms called chitinozoans. Chitinozoans are organic-walled, planktonic microfossils that first appear in the Early Ordovician Period (488 million years ago) and diversify rapidly through the Paleozoic Era. The Ordovician Period was a time of great global climate change, and by studying this group of fossil plankton, we hope to better understand how modern plankton, which are the base of the marine food chain, might respond to climate change. We used a method called constrained optimization (CONOP9) to construct a composite range chart of 152 …

Population Variation In Fossil Graptolites: A Quantitative Study Based On Single Species Assemblages, Elliott Matthias Mazur

Honors Theses

There are several different types of variation in populations of fossil organisms. These include intra-specific (population) variation, evolutionary variation (specimens on a slab accumulating over thousands of years), and preservational variation. An understanding of the extent and type of variation present in a population is fundamental to biological and paleontological studies. This study examines several populations of fossil graptolites from which population variation can be studied without the influence of the other types, and includes several types of morphometric analyses to examine population variation in several species of fossil graptolites. These analyses include isolating three dimensionally preserved specimens from limestone, …