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Physical Sciences and Mathematics Commons

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Geology

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University of Dayton

Series

2014

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Population Variation In Fossil Graptolites: A Quantitative Study Based On Single Species Assemblages, Elliott Matthias Mazur Apr 2014

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, …


Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu Jan 2014

Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu

Geology Faculty Publications

Reconstruction of the Hirnantian (Late Ordovician) palaeotopography in South China is important for understanding the distribution pattern of the Hirnantian marine depositional environment. In this study, we reconstructed the Hirnantian palaeotopography in the Upper Yangtze region based on the rankings of the palaeo-water depths, which were inferred according to the lithofacies and biofacies characteristics of the sections. Data from 374 Hirnantian sections were collected and standardized through the online Geobiodiversity Database. The Ordinary Kriging interpolation method in the ArcGIS software was applied to create the continuous surface of the palaeo-water depths, i.e. the Hirnantian palaeotopography. Meanwhile, the line transect analysis …