Results 31 to 40 of about 23,609 (212)
Petrographic and Geochemical Analyses of Kirana Hills Shield Rocks around Sargodha and Economic Potential [PDF]
International Journal of Economic and Environment Geology, 2017 The present study deals with geochemical and petrographic analysis of the Kirana Hill shield rocks of Punjab plains from Buland, Hachi, Shaheen Abad, Shaikh and Machh hills.
Muhammad Waseem Khan +3 more
doaj
Rhyolite grinding-milling tools in focus
Archeologické Rozhledy, 2023 Past societies have used various raw materials for making grinding-milling tools (GMT). These included rhyolite, a hard volcanic rock with a porphyritic texture and pores, which is suitable for grinding.
Kristina Doležalová +2 more
doaj +1 more source
JGEThe earth's subsurface can be composed of various rocks such as igneous rocks, sedimentary rocks, and metamorphic rocks. Determination of rock types below the surface is carried out using geophysical methods. This study aims to identify Rhyolite-Andesite
Rizky Ramadhan Dwiyantoro +2 more
doaj +1 more source
Frontiers in Earth Science, 2022 The 7.1 Ma Rattlesnake Tuff (RST) of eastern Oregon is a widespread and voluminous (>300 km3) ignimbrite composed of 99% crystal poor (≤1%) high-silica rhyolite (HSR) and <1% dacites.
Vanessa M. Swenton, Martin J. Streck
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Spherulite formation in obsidian lavas in the Aeolian Islands, Italy [PDF]
, 2017 The authors wish to gratefully acknowledge Andy Tindle (The Open University) for assistance with EMP analyses, and Richard Darton and David Evans (Keele University) for assistance with XRD and Prof Alun Vaughan and Nicola Freebody (University of ...
Bullock, Liam A. +2 more
core +2 more sources
The effect of fluorine on viscosities in the system Na2O-Al2O3-SiO2: implications for phonolites, trachytes and rhyolites [PDF]
, 1985 The effect of fluorine on melt viscosities of five compositions in the system Na2O-Al2O3- SiO2h as been investigateda t one atmospherea nd 1000-1600'Cb y concentric-cylinder viscometry.
Cronin, David J. +2 more
core +1 more source
Volcanica, 2020 Magma degassing mechanisms are key determinants of explosive and effusive eruption styles. Paired measurements of H2O content and hydrogen isotopic ratios (e.g., δD) in pyroclastic and effusive products can elucidate end-member degassing mechanisms (e.g.
Sebastian Walter, Jonathan Castro
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Elemental, isotopic, and geochronological variability in Mogollon-Datil volcanic province archaeological obsidian, southwestern USA: Solving issues of intersource discrimination [PDF]
, 2017 Solving issues of intersource discrimination in archaeological obsidian is a recurring problem in geoarchaeological investigation, particularly since the number of known sources of archaeological obsidian worldwide has grown nearly exponentially in the ...
Morgan, L, Pyle, D, Shackley, MS
core +1 more source
High‐Titanium Zircon Rims in Rhyolite – A Reflection of Adiabatic Ascent?
Geological Journal, EarlyView.The ascent of granitic magma from source to emplacement is rapidly achieved through dyking, resulting in negligible heat loss to the surrounding wallrock (i.e., adiabatic). Zircon growth during ascent can record the changing magma conditions including adiabatic cooling and heating, resulting in high titanium rims on low titanium cores without ...
Carson Kinney +2 more
wiley +1 more source
Geosciences, 2019 The oceanic crust consists mostly of basalt, but more evolved compositions may be far more common than previously thought. To aid in distinguishing rhyolite from basaltic lava and help guide sampling and understand spatial distribution, we constructed a ...
Christina H. Maschmeyer +3 more
doaj +1 more source