Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Institution
- Publication
- Publication Type
Articles 1 - 6 of 6
Full-Text Articles in Geological Engineering
Geochemical Evidence Of Drying During The 4.2 Ka Event In Sediment Cores From The Yucatán Peninsula, Mexico, Derek K. Gibson, Jonathan Obrist-Farner, Alex Correa-Metrio, Alejandra Rodriguez-Abaunza, Carlos Castañeda-Posadas
Geochemical Evidence Of Drying During The 4.2 Ka Event In Sediment Cores From The Yucatán Peninsula, Mexico, Derek K. Gibson, Jonathan Obrist-Farner, Alex Correa-Metrio, Alejandra Rodriguez-Abaunza, Carlos Castañeda-Posadas
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Tropical hydroclimate variability during the Middle and Late Holocene was investigated using geochemical indicators of local-scale precipitation and evaporation preserved in sediment cores from two sites in the Mexican Yucatán Peninsula. Scanning X-Ray fluorescence spectroscopy data show generally decreasing precipitation trends during the Early and Middle Holocene. During the transition between the Middle and Late Holocene, geochemical evidence of reduced watershed erosion and increased evaporation indicate that a centennial-scale drying event impacted the region between 4.3 and 4.0 ka (kilo-anum; thousand years before present). These findings suggest that the 4.2 ka drying event, which has been previously recorded in Europe, …
Covid-19 Pandemic Lockdown Modulation Of Physico-Chemical Parameters Of Surface Water, Karamana River Basin, Southwest India: A Weighted Arithmetic Index And Geostatistical Perspective, S. P. Prasood, M. V. Mukesh, K. S. Sajinkumar, K. P. Thrivikramji
Covid-19 Pandemic Lockdown Modulation Of Physico-Chemical Parameters Of Surface Water, Karamana River Basin, Southwest India: A Weighted Arithmetic Index And Geostatistical Perspective, S. P. Prasood, M. V. Mukesh, K. S. Sajinkumar, K. P. Thrivikramji
Michigan Tech Publications
The coronavirus disease or COVID-19 pandemic continues imposing restrictions on the human population from full-scale normal/routine activities all over the world. This study primarily spotlights the consequences of the COVID-19-pandemic-lockdown on physicochemical parameters of water (samples) of the Karamana river system (KRS) during the pre-monsoons (or January) of 2021 and 2022, using the Weighted Arithmetic Index method and Geostatistical analysis (ArcMap 10.2). Even though the Karamana river supported the water needs of the people during the past several decades, the quality of water deteriorated due to the rising population and consequent anthropogenic activities. Hence, it is imperative to evaluate the …
Mineralogy And Fluid Inclusion Study Of The Crystal Mountain Fluorite Mine, Ravalli County, Montana, Francis Grondin
Mineralogy And Fluid Inclusion Study Of The Crystal Mountain Fluorite Mine, Ravalli County, Montana, Francis Grondin
Graduate Theses & Non-Theses
The Crystal Mountain Fluorite Mine, known for its vast amounts of massively grown fluorite and rare accessory minerals including fergusonite (YNbO4) and thortveitite (Sc2Si2O7), is located in the Sapphire Mountains 22 km east of the town of Darby, Montana. This site has been mined previously between the years of 1954 through 1973. The Taber collection of drill core, thin sections, mine maps and miscellaneous reports on Crystal Mountain was recently donated to the Montana Bureau of Mines and Geology for future studies. The purpose of the present study has been to use …
Geochemistry Of Metals And Nutrients In Fine-Sediment Pore Water In Blacktail And Silver Bow Creeks, Butte, Montana, Robert Radar
Geochemistry Of Metals And Nutrients In Fine-Sediment Pore Water In Blacktail And Silver Bow Creeks, Butte, Montana, Robert Radar
Graduate Theses & Non-Theses
Historical mining in Butte, Montana has impacted surface and groundwater in the area. Although most of the known sources of contaminants of concern have been removed or remediated, metal loading continues to occur in lower Blacktail Creek and upper Silver Bow Creek. Possible sources of metals include upwelling groundwater and interaction between the stream and metal-rich sediment in the stream bed. To assess the importance of fine sediment as a source (or sink) for metals, this investigation used sediment pore water diffusion samplers (“peepers”). Peepers are ideal for capturing cm-scale vertical gradients in pore water chemistry across the sediment-water interface. …
Mineralogy And Sulfur Isotope Geochemistry Of The Apex And Bonanza Prospects At The Golden Sunlight Mine, Montana, Hamadou Gnanou
Mineralogy And Sulfur Isotope Geochemistry Of The Apex And Bonanza Prospects At The Golden Sunlight Mine, Montana, Hamadou Gnanou
Graduate Theses & Non-Theses
The Golden Sunlight mine, located 50 km to the east of the famous Butte porphyry/lode deposits, is the largest gold mine in Montana, and has produced over 3 million ounces of gold in its 35+ year history. Most of this gold has come from the Mineral Hill breccia pipe (MHBP), a west dipping, cylindrical body of brecciated latite and country rock fragments of the Precambrian LaHood and Greyson Formations. The breccia pipe is late Cretaceous in age (84±18 Ma, DeWitt et al., 1986), is silicified, pyrite-rich, and is mineralized with gold, silver, and minor base metals. Because the MHBP has …
Effect Of Variable-Ph Landfill Leachate On A Carbonate Rock Aggregate, William L. Niemann, Allen W. Hatheway
Effect Of Variable-Ph Landfill Leachate On A Carbonate Rock Aggregate, William L. Niemann, Allen W. Hatheway
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Carbonate rock aggregate is commonly used as drainage stone in leachate collection systems of RCRA Subtitle D landfills. U.S. EPA technical guidance for waste containment facilities states that excessive carbonate in drainage stone may result in dissolution and clogging at sites of reprecipitation (Daniel and Koerner, 1993, p. 197). Unfortunately, this theoretical concern does not appear to be confirmed by any experimental evidence with typical landfill leachate or documented instances of clogging at typical Subtitle D landfills. This paper describes a practical laboratory experiment that measured the effects of landfill leachate - maintained at three distinct pH levels - on …