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Showing 1 to 20 of 21 for “"geochemical evolution"”.
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Geochemical Evolution at White Island, New Zealand
… from crystallizing. The tectonic setting and geochemical characteristics of the magma body at White Island are similar to features observed in economic porphyry systems elsewhere. These data suggest that development of economic porphyry copper mineralization at White Island is likely.
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Seasonal Effects on the Geochemical Evolution of the Logsdon River, Mammoth Cave, Kentucky
… describes the collection and evaluation of geochemical data from the Logsdon River, an open-flow conduit that drains a portion of the Turnhole Spring drainage basin within the Mammoth Cave karst aquifer of south-central Kentucky. This spatial survey of nearly 10 km of continuous base-level …
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Volcanic framework and geochemical evolution of the Archean Hope Bay Greenstone Belt, Nunavut, Canada
… distinct suites based upon field, petrologic, geochemical, and geochronologic criteria. Some of the suites are stratigraphically continuous and can be correlated tens of kilometres along strike thereby linking the two parts of the Hope Bay Greenstone Belt. U-Pb geochronology supports work by …
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The geochemical evolution of saline groundwater within a fresh water aquifer south of Oakes, North Dakota
<p>An area of saline/brackish groundwater south of Oakes, North Dakota has been reported by the North Dakota State Water Commission. The concentrated water (over 12,000 mg/L of total dissolved solids) is in direct hydraulic connection with relatively fresh water and shows an abrupt change in …
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Petrology and Geochemical Evolution of the East Hill Suite of the Mont Saint-Hilaire Alkaline Plutonic Complex
… syenoids. A lamprophyric unit stands on its own, geochemically, consistent with typical lamprophyre petrogenesis. Whole-rock geochemistry of the East Hill suite shows moderate silica content but highly alkaline rocks, enriched in Mn, Zn, Zr, Y, and Ce. Chlorine and sulfur are important and present …
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Proterozoic thermal and deformational history and geochemical evolution of the 1.4 Ga Priest pluton and its aureole
… is a heterogeneous source region. Therefore, geochemical signatures that are commonly associated with particular tectonic settings may instead be a reflection of heterogeneities in the source.
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A Chemical and Isotopic Investigation of the Groundwater in the Mahomet Bedrock Valley Aquifer: Age, Recharge and Geochemical Evolution of the Groundwater
… in a conceptual model explaining the variable geochemical characteristics across the MA. The 14C data indicates that the MA is well protected from surficial contamination.
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Solute Chemistry and Isotopic Investigation of the Groundwater Flow Paths in Honey Lake Basin, Lassen County, California and Washoe County, Nevada
… cold and two thermal, are identified and the geochemical evolution of those paths are characterized by integrating solute chemistry and isotopic data. The chemical flow paths include recharge in either granitoid or volcanic terrains in the Sierra Nevada Range and the Modoc Plateau, …
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Tracing the input and evolution of municipal water in springs and tributaries of the Bull Creek watershed, Austin, TX
… a better understanding of the processes of geochemical evolution as anthropogenically-sourced water recharges natural systems. Urbanization patterns in the Bull Creek watershed have created a contiguous expanse of urban development that covers roughly two thirds of the watershed, whereas the …
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Sources of CO<sub>2</sub> Controlling the Carbonate Chemistry of the Logsdon River, Mammoth Cave, Kentucky
… has provided a unique opportunity to examine the geochemical evolution of a stream flowing through a major karst conduit that can be traversed for 10 km. This study examines CO<sub>2</sub> inputs at the upstream portion of the river, which provide major control for the river’s hydrochemistry. …
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Geochemical methods for evaluating the origin and evolution of ground water in volcanic rocks
A broad-based geochemical approach, including chemical and isotopic analyses of ground water, chemical analysis of aquifer materials, and laboratory water-rock experiments, was used to evaluate the origin and chemical evolution of ground water on La Palma, a volcanic island in the Canary …
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The evolution of oceanic gabbros : in-situ and ancient examples
This study is a geochemical investigation into the accretion of lower oceanic crust and processes of shallow melt-rock reaction at mid-ocean ridges. Major-, trace-elements, and isotopes from whole-rocks and minerals from the Lyngen Gabbro, a 480-My old dismembered ophiolite from the Scandinavian …
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Characterizing Variable Flow Pathways And Geochemical History Of Seepage Under The Mississippi River Levee: 2011, 2015, And 2016 Floods
… understanding of the nature of flow and the geochemical evolution of the local groundwater. Geochemical signatures identify distinct deep and shallow flow pathways. Deeper flow pathways have lower redox potential, high fe and as, and higher barium to calcium ratios. Tds values were of the …
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Analysis of coal combustion by-product disposal practices in an arid climate : leachate water quality
… and old buried CCBs, and investigated the geochemical transformations that occur with time. Samples of CCBs ranged in age from less than a year old to over 30 years old. These samples were subjected to batch leaching tests as well leaching in unsaturated column tests. The mineralogy and …
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Evolution of oceanic gabbros : in-situ and ancient examples
This study is a geochemical investigation into the accretion of lower oceanic crust and processes of shallow melt-rock reaction at mid-ocean ridges. Major-, trace-elements, and isotopes from whole-rocks and minerals from the Lyngen Gabbro, a 480-My old dismembered ophiolite from the Scandinavian …
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Isotopic, geochemical, and geochronological constraints on the origin and evolution of Cenozoic volcanism, Baikal Rift Zone, Siberia
… Baikal. This large-scale study investigates the geochemical evolution of the Baikal Rift Zone volcanism using major element, trace element, and isotopic (Sr, Nd, and Pb) geochemistry, as well as 40Ar/39Ar geochronology. In addition, a detailed isotopic study of megacrysts provides insight into …
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Sub-surface geology, petrochemistry and hydrothermal alteration of Wells MW-03, MW-09 and MW-20 from Menengai geothermal field, Kenya
… neighbouring wells MW-04, MW-06 and MW-07. The geochemical evolution of Menengai rocks seems to be mainly controlled by fractional crystallization. However, more than one process are involved. The realionship between trace elements with depth in wells MW-03, MW-09 and MW-20 depict four volcanic …
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Quantifying Crustal Assimilation in Historical to Recent (1329-2005) Lavas at Mt. Etna, Italy: Insights from Thermodynamic Modeling
… an excellent opportunity to investigate the geochemical evolution of a highly active volcano. Of particular interest is elucidating the cause of a selective enrichment in alkali elements (K, Rb, Cs) and <sup>87</sup>Sr/<sup>86</sup>Sr. This alkali enrichment trend, which began in the …
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Spatial-Statistical Properties of Geochemical Variability as Constraints on Magma Transport and Evolution Processes at Ocean Ridges
… ridges represent a critical setting for many geochemical fractionation processes involved in the chemical evolution of the silicate Earth, and are fundamental to the plate tectonic cycle. Because of the inherent inaccessibility, it remains an ongoing challenge to interpret the geochemistry of …
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The origins of olivine fabric transitions and their effects on seismic anisotropy in the upper mantle
… mantle plays a central role in the thermal and geochemical evolution of the Earth. It provides the principal force responsible for major geological features such as mountains and ocean basins. Plate tectonics and its violent consequences such as earthquakes and volcanoes are all manifestations …
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