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Colloidal gold and silica in mesothermal vein systems
Geology, 1993Some of the textural features of mesothermal gold-quartz veins may be best explained by the initial precipitation of amorphous silica gel (colloid), which subsequently crystallizes to quartz. This can occur in brittle-ductile shear zones where a significant fluid-pressure drop occurs during stick-slip failure.
R. J. Herrington, J. J. Wilkinson
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Mesothermal plasma flow around a negatively wake side biased cylinder
Journal of Geophysical Research: Space Physics, 1991We have made a numerical investigation of the wake potential and density perturbations caused by the presence of a large negative voltage on a sector situated on the wake side of a spacecraft moving at orbital speed through the ionosphere. The spacecraft is represented as an infinite cylinder moving in an unmagnetized plasma. The rest of the cylinder's
Éric Coggiola, Amaury Soubeyran
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Can lamprophyres resolve the genetic controversy over mesothermal gold deposits?
Geology, 1988Associations between calc-alkaline lamprophyres and mesothermal gold deposits (Archean to Tertiary) in which the lamprophyres are coeval (as well as cospatial) with mineralization are increasingly recognized worldwide. Our suggested hypothesis regards lamprophyres as transporting agents for Au from Au-rich sources in the deep mantle, which then undergo
Nicholas M.S. Rock, David I. Groves
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Electron Properties in Collisionless Mesothermal Plasma Expansion: Fully Kinetic Simulations
IEEE Transactions on Plasma Science, 2015This paper presents a fully kinetic particle-in-cell simulation of collisionless mesothermal plasma expansion with a focus on the macroscopic electron properties. The results show that the electron thermal properties are anisotropic and nonuniform. In the beam core region, the electrons are thermalized due to interactions between the trapped electrons ...
Yuan Hu, Joseph Wang
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Alteration of biotite under mesothermal conditions
Economic Geology, 1958The complex chemical composition of biotite is doubtless the cause of a variety of alteration products when it has been altered by hydrothermal solutions at moderate temperatures and pressures. As a rule biotite is unstable under hydrothermal conditions and alters to numerous minerals that seem to depend primarily on the composition of the solution at ...
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Near wake of the rarefied plasma flows at mesothermal speeds
6th Aerospace Sciences Meeting, 1968Plasma interaction between negatively charged body and tenuous plasma stream, discussing near wake of rarefied plasma flows at mesothermal ...
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Current Coupling Via Electron Emission in Fast and Mesothermal Ion Beams
2018 IEEE International Conference on Plasma Science (ICOPS), 2018Ion beam neutralization during operation of ion sources requires current coupling between beam ions and electrons from the neutralizer. The current and charge density equalization during neutralization is accomplished in practice, however, the exact process has not been adequately simulated/understood due to the wide range of conditions.
Daoru Han +2 more
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Geology of the Hammer Down mesothermal gold deposit, Newfoundland Appalachians, Canada
Canadian Journal of Earth Sciences, 1996The Hammer Down gold deposit is one of the most significant mesothermal vein-type gold deposits in the Canadian Appalachians. It is located within a complex sequence of Ordovician, mafic-dominated tholeiitic and calc-alkalic and arc-related volcanic rocks, which was intruded by Silurian felsic porphyry dykes.
Gaboury, Damien +3 more
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Distribution of plasma density and potential around a mesothermal ionospheric object
Journal of Geophysical Research: Space Physics, 1989For an object moving at mesothermal speeds in a collisionless plasma it is shown that the ion thermal motion as well as the coupling of the disturbances in front of the object to the wake region play significant roles in modifying the plasma environment around the object.
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Crustal Hydrothermal Fluids and Mesothermal Mineral Deposits
1992In this chapter we examine a broad category of hydrothermal mineral deposits whose principal characteristic is their strong structural control, and whose genesis is attributed to the action of deep-circulating crustal fluids. The mineralisation is hosted in a variety of lithologies metamorphosed to lower-upper greenschist facies, and less commonly to ...
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