Open Access. Powered by Scholars. Published by Universities.®

Geology Commons™

Open Access. Powered by Scholars. Published by Universities.®

29,955 Full-Text Articles 16,143 Authors 6,782,393 Downloads 178 Institutions

All Articles in Geology

Faceted Search

29,955 full-text articles. Page 260 of 1249.

Mgrre_Thinsections_Mgrre-04_17, MGRRE 2022 Western Michigan University

Mgrre_Thinsections_Mgrre-04_17, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_Mgrre-04_18, MGRRE 2022 Western Michigan University

Mgrre_Thinsections_Mgrre-04_18, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_Mgrre-04_19, MGRRE 2022 Western Michigan University

Mgrre_Thinsections_Mgrre-04_19, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_Mgrre-04_20, MGRRE 2022 Western Michigan University

Mgrre_Thinsections_Mgrre-04_20, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_Mgrre-02_3, MGRRE 2022 Western Michigan University

Mgrre_Thinsections_Mgrre-02_3, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_Mgrre-02_11, MGRRE 2022 Western Michigan University

Mgrre_Thinsections_Mgrre-02_11, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_Mgrre-02_20, MGRRE 2022 Western Michigan University

Mgrre_Thinsections_Mgrre-02_20, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_Mgrre-02_15, MGRRE 2022 Western Michigan University

Mgrre_Thinsections_Mgrre-02_15, Mgrre

Thin Sections

No abstract provided.


Mgrre_Thinsections_Mgrre-04_15, MGRRE 2022 Western Michigan University

Mgrre_Thinsections_Mgrre-04_15, Mgrre

Thin Sections

No abstract provided.


Hydrogen Isotope Behavior During Rhyolite Glass Hydration Under Hydrothermal Conditions, Michael R. Hudak, Ilya N. Bindeman, James M. Watkins, Jacob B. Lowenstern 2022 University of Oregon, Woods Hole Oceanographic Institution

Hydrogen Isotope Behavior During Rhyolite Glass Hydration Under Hydrothermal Conditions, Michael R. Hudak, Ilya N. Bindeman, James M. Watkins, Jacob B. Lowenstern

United States Geological Survey: Staff Publications

The diffusion of molecular water (H2Om) from the environment into volcanic glass can hydrate the glass up to several wt% at low temperature over long timescales. During this process, the water imprints its hydrogen isotope composition (δDH2O) to the glass (δDgl) offset by a glass-H2O fractionation factor (ΔDgl-H2O = δDgl – δDH2O) which is approximately -33‰ at Earth surface temperatures. Glasses hydrate much more rapidly at higher, sub-magmatic temperatures as they interact with H2O during eruption, transport, and emplacement. To aid in the interpretation …


Evaluating Our Reliance On Rare Earth Minerals And Platinum Group Metals Over The Period Of 2012 To 2021, Ryan Smith 2022 Longwood University

Evaluating Our Reliance On Rare Earth Minerals And Platinum Group Metals Over The Period Of 2012 To 2021, Ryan Smith

Fall Showcase for Research and Creative Inquiry

Rare Earth Elements (REE’s) are minerals used in our everyday lives. They can be found in our household appliances, phones, computers, cars, as part of wind turbines and solar panels. The US relies on imports of these rare earths from several other countries (e.g. China, Estonia, Malaysia, and Japan) as we cannot mine a majority of the minerals (e.g. cerium, lanthanum, europium, etc) domestically. Since the year 2012, the US has imported approximately 3,000 metric tons of rare earths, and in recent years, this number significantly increased. As of 2021, the US now imports approximately 43,000 metric tons of rare …


Mgrre_Thinsections_05_A_37, MGRRE 2022 Western Michigan University

Mgrre_Thinsections_05_A_37, Mgrre

Thin Sections

No abstract provided.


Intact Polar Brgdgts In Arctic Lake Catchments: Implications For Lipid Sources And Paleoclimate Applications, Jonathan H. Raberg, Edgart Flores, Sarah E. Crump, Greg de Wet, Nadia Dildar, Gifford H. Miller, Áslaug Geirsdóttir, Julio Sepúlveda 2022 University of Colorado Boulder

Intact Polar Brgdgts In Arctic Lake Catchments: Implications For Lipid Sources And Paleoclimate Applications, Jonathan H. Raberg, Edgart Flores, Sarah E. Crump, Greg De Wet, Nadia Dildar, Gifford H. Miller, Áslaug Geirsdóttir, Julio Sepúlveda

Geosciences: Faculty Publications

Paleotemperature histories derived from lake sediment archives provide valuable context for modern and future climate changes. Branched glycerol dialkyl glycerol tetraether (brGDGT) lipids are a valuable tool in such pursuits due to their empirical correlation with temperature and near ubiquity in nature. However, the relative contributions of terrestrial and lacustrine sources of brGDGTs to lake sediments is site-dependent and difficult to constrain. Here, we explored the potential for intact brGDGTs—the complete lipids with polar head groups (HGs) still attached—to provide insight into the sources of brGDGTs on the landscape and their contributions to the sedimentary record in a set of …


Sulfur Behavior In The 1257 Ce Samalas Magma (Lombok, Indonesia) As Revealed By Volcanic Apatite, Yasmin Jackson 2022 Southern Methodist University

Sulfur Behavior In The 1257 Ce Samalas Magma (Lombok, Indonesia) As Revealed By Volcanic Apatite, Yasmin Jackson

Earth Sciences Theses and Dissertations

Explosive volcanic eruptions can inject massive amounts of volatiles, including SO2 and H2S, into the stratosphere, inducing drastic tropospheric cooling via sulfate aerosols. Greenland and Antarctic ice cores record evidence of these substantial releases of SO2 and H2S, including the massive release during the ultraplinian 1257 CE Samalas eruption. The 1257 CE Samalas eruption is estimated to have released ~158 Tg of SO2, making it the largest volcanogenic release of SO2 within the last 2000 years. Vidal et al. (2016) propose that most of this sulfur (S) was hosted in a …


Soils Of The Central Nebraska Loess Hills And Central Loess Plains, Judith Turk, Rebecca Young, Nicolas A. Jelinsky, Amber D. Anderson, Ashlee Dere, Colby J. Moorberg, Rachel K. Owen 2022 University of Nebraska - Lincoln

Soils Of The Central Nebraska Loess Hills And Central Loess Plains, Judith Turk, Rebecca Young, Nicolas A. Jelinsky, Amber D. Anderson, Ashlee Dere, Colby J. Moorberg, Rachel K. Owen

Conservation and Survey Division: Faculty and Staff Publications

Understanding soil systems that characterize a region is critical to natural resource management. However, the knowledge gained through intensive study of local soil systems, which takes place annually as part of collegiate soil judging contests, is often poorly preserved for future use. In this study, field descriptions and laboratory data for 16 soil profiles described for the 2019 Region 5 Soil Judging Contest were used to characterize the soil system of the Central Nebraska Loess Hills and Central Loess Plains. Three landscape components of this soil system were analyzed: the loess uplands and rainwater basins, the transitional zone, and bottomlands. …


Mgrre_Thinsections_05_A_36, MGRRE 2022 Western Michigan University

Mgrre_Thinsections_05_A_36, Mgrre

Thin Sections

No abstract provided.


Evaluation Of Enzymatic Activity During Growth Of Pleurotus Hk 37 On Saba Comorensis Exocarp, Isse I. Molobele, Rose J. Masalu, Prosper R. Mosha, Cyprian B. Mpinda 2022 Department of Molecular Biology and Biotechnology, University of Dar es Salaam. P.O Box 35179, Dar es Salaam, Tanzania.

Evaluation Of Enzymatic Activity During Growth Of Pleurotus Hk 37 On Saba Comorensis Exocarp, Isse I. Molobele, Rose J. Masalu, Prosper R. Mosha, Cyprian B. Mpinda

Tanzania Journal of Science

Mushrooms degrade lignocellulosic biomass by releasing lignolytic and hydrolytic enzymes which convert lignocellulosic material into soluble and low molecular weight compounds which are then absorbed as nutrients. In the present study, enzymatic activities of Pleurotus HK 37 during growth on Saba comorensis exocarps were evaluated. It was observed that, Pleurotus HK 37 has ability to produce lignolytic enzyme (Laccase) and hydrolytic enzymes (Carboxymethyl cellulase, xylanase and filterpaperase). Maximum laccase activity of 3.33 ± 0 UmL-1 was observed during colonization period and the activity dropped during fruitification phase. Similar to hydrolytic enzymes, the activity was observed during colonization period and decreased …


Effects Of Small-Scale Mining Activities On Fisheries And Livelihoods In The Birim River In Atiwa District, Eastern Region Of Ghana, Elliot Haruna Alhassan, Samuel Opoku Dandi, Sandra Akugpoka Atindana 2022 Department of Fisheries and Aquatic Resources Management, Faculty of Biosciences, University for Development Studies, Tamale-Ghana

Effects Of Small-Scale Mining Activities On Fisheries And Livelihoods In The Birim River In Atiwa District, Eastern Region Of Ghana, Elliot Haruna Alhassan, Samuel Opoku Dandi, Sandra Akugpoka Atindana

Tanzania Journal of Science

The socioeconomic importance of small-scale mining in Ghana is of great interest to the country. It provides employment, supports the livelihood of poor rural areas, and also contributes to national income. Despite all these importance, it has a great influence on the surroundings, with surface and groundwater bodies being the most affected. The study was conducted to determine the effects of small-scale mining activities on fisheries and livelihoods along the Birim River in Atiwa District of Ghana, and also, to ascertain the nature of mining in the catchment and the current status of fisheries in the river. Data were collected …


Drivers Of Pb, Sb And As Release From Spent Gunshot In Wetlands: Enhancement By Organic Matter And Native Microorganisms, Anna Potysz, Łukasz J. Binkowski, Jakub Kierczak, Barnett A. Rattner 2022 University of Wrocław

Drivers Of Pb, Sb And As Release From Spent Gunshot In Wetlands: Enhancement By Organic Matter And Native Microorganisms, Anna Potysz, Łukasz J. Binkowski, Jakub Kierczak, Barnett A. Rattner

United States Geological Survey: Staff Publications

In many countries the use of lead-based ammunition is prevalent, and results in exposure and poisoning of waterfowl and other species of birds. In waterfowl hunting areas large quantities of spent shot may be deposited in wetland and terrestrial habitats. These pellets can undergo transformations, which are influenced by various abiotic and biotic factors. In addition to lead (Pb), other elements like antimony (Sb) and arsenic (As) can be leached from Pb shot into the environment. In vitro simulations that included organic matter and microorganisms were utilized to examine elemental leaching from gunshot. We found that leaching efficiency was the …


Mgrre_Thinsections_05_A_35, MGRRE 2022 Western Michigan University

Mgrre_Thinsections_05_A_35, Mgrre

Thin Sections

No abstract provided.


Digital Commons powered by bepress