Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Physical Sciences and Mathematics
Org Or Inorg? Atmospheric Carbon Controls That Initiated The Late Paleozoic Ice Age 326mya, Paco Defrancis
Org Or Inorg? Atmospheric Carbon Controls That Initiated The Late Paleozoic Ice Age 326mya, Paco Defrancis
CLAS: Colby Liberal Arts Symposium
The Late Paleozoic Ice Age (LPIA) was a major global icehouse that initiated in the Mississippian (326 million years ago; ma) and lasted through the Early Permian (267ma). An ice sheet nucleated in southern Gondwana near the South Pole, which either paleogeography (positioning of paleocontinents) or atmospheric concentration of the greenhouse gas CO2 controlled. In this paper I accept recent findings that prove atmospheric pCO2 and not paleogeography forced global cooling that resulted in the nucleation of Gondwanan ice sheets that defined the LPIA. There remains no broad consensus of what caused pCO2 lowering in the Mississippian. Organic carbon found …
From The Depths Of Great Pond (Maine): Anthropogenic And Natural Influences On Bottom Sediments And The Implications For Local Sustainability, Sara George, Clara Bicher
From The Depths Of Great Pond (Maine): Anthropogenic And Natural Influences On Bottom Sediments And The Implications For Local Sustainability, Sara George, Clara Bicher
CLAS: Colby Liberal Arts Symposium
As part of a Maine EPSCoR grant focusing on sustainability in the Belgrade Lakes watershed of central Maine, current research consists of collecting bottom sediment samples from Great Pond. Samples were analyzed to create a sediment map of the lake basin in regards to depth, grain-size distribution, organic content (%C), C:N ratios and phosphorus concentration. Results will aid in the understanding of the glacial formation of the lake, distribution of sediment within, and human impact on the lake. Additionally, knowing the distribution of phosphorus within the sediments may allow development of a strategy to avoid accelerated eutrophication. This research will …
My Pet Mineral: Augite, Jacob Wall
My Pet Mineral: Augite, Jacob Wall
CLAS: Colby Liberal Arts Symposium
Augite is typically known for its greenish black color, nice vitreous luster, two directions of cleavage and of course its simple chemical formula: (Ca,Na,Mg,Fe2+,Fe3+Al,Ti)2[(Si,Al)2]O6]. Augite has a hardness of 5.5, 2 planes of cleavage and massive habit. Augite is an important rock-forming silicate mineral and occurs in a wide variety of basic igneous rocks, including gabbros, dolerites and basalts. Augite also occurs in ultrabasic and intermediate rocks as well as a limited number of high-grade metamorphic rocks such as granulites and charnockites. Augites range widely in composition and show a continuoius variation in chemical composition. Iron rich augites are restricted …