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Articles 31 - 34 of 34

Full-Text Articles in Paleobiology

Biogenic Tracers Through The Holocene On The Alaskan Shelf, Carie A. Curry Jan 2009

Biogenic Tracers Through The Holocene On The Alaskan Shelf, Carie A. Curry

OES Theses and Dissertations

Dramatic environmental changes in the Arctic Ocean have been observed for the last two decades including changing the amount of sea ice thickness and extent, and increased river discharge. In order to put these and other current day observations into historical context and perhaps reveal mechanisms controlling them, a suite of paleo-proxies were used to analyze two high resolution cores collected on the 2005 HOTRAX expedition. The goals of this research were: (1) develop an analytical method for determining biogenic calcite, (2) identify the major sources of biogenic matter into the system over the Holocene, and (3) assemble the history …


A Biogeochemical Comparison Of Fossil (Carboniferous) And Modern Crustose Red Algae, Michael A. Kruge, John E. Utgaard, William Ferry Jan 1999

A Biogeochemical Comparison Of Fossil (Carboniferous) And Modern Crustose Red Algae, Michael A. Kruge, John E. Utgaard, William Ferry

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The nature of the contribution of the various types of algae to sedimentary organic matter continues to be a topic of research interest. Crustose red algae have however received less attention than other types. The fossil calcareous red algae (Rhodophyta) analyzed in this study are two relatively unrecrystallized specimens of Parachaetetes (Family Solenoporacea) from the lower part of the Ste. Genevieve Formation (Carboniferous, Visean) in Union County, Illinois, USA. They occurred in the patch reef phase of a small carbonate mudmound-patchreef. The three modern specimens (collected and identified by F. Collier) are the crustose algae Lithothamnion, Clathromorphum and Phymatolithon …


Environmental And Botanical Controls On Peatification - A Comparative Study Of Two New Zealand Restiad Bogs Using Py-Gc/Ms, Petrography And Fungal Analysis, Tomasz K. Kuder, Michael A. Kruge, J C. Shearer, S L. Miller Jan 1998

Environmental And Botanical Controls On Peatification - A Comparative Study Of Two New Zealand Restiad Bogs Using Py-Gc/Ms, Petrography And Fungal Analysis, Tomasz K. Kuder, Michael A. Kruge, J C. Shearer, S L. Miller

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

This study shows that chemical properties of two restiad species, Empodisma minus and Sporadanthus traversii, may contribute to their success as peat-formers in a climate of the North Island of New Zealand which is not conducive to raised mire development. Unlike Sphagnum, the equivalent northern hemisphere peat-former, restiads possess lignin in their tissues. In addition, the presence of non-lignin polyphenols (including tannins and phenolic acids) in restiads may be an important factor in peat formation due to the allelopathic decay retardation. Patterns of degradation of plant biopolymers have been examined and the pathway of degradation of monocotyledons (loss …


Petrographic And Chemical Properties Of Carboniferous Resinite From The Herrin No. 6 Coal Seam, John C. Crelling, Michael A. Kruge Jan 1998

Petrographic And Chemical Properties Of Carboniferous Resinite From The Herrin No. 6 Coal Seam, John C. Crelling, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Resinite is a naturally occurring substance found in coal and derived from original plant resins. It is ubiquitous in North American coals and comprises 1 to 4% by volume of most Illinois coals. It has been commercially exploited in the western USA for use in adhesives, varnishes and thermal-setting inks. The major objectives of this study were: (1) to separate resinite macerals from the Herrin No. 6 coal seam and to carefully verify, by petrographic and fluorescence microspectrophotometric methods, that the separated material was indeed resinite; (2) to characterize the chemical composition of the separated resinite by Py–GC–MS techniques; and …