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Metamorphism and Metamorphic Rocks
, 2013 In the previous chapters, we learned about igneous and sedimentary rocks. This chapter presents some general concepts concerned with the process of metamorphism and the formation of metamorphic rocks. How pressure, temperature, and fluids control metamorphic processes and resulting metamorphic changes are discussed.
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Deep Underground Science and Engineering, EarlyView.This review elucidates the velocity–dispersion–attenuation coupling mechanisms of wave propagation in rock masses, compares six representative models, and reveals how pressure, temperature, mineral composition, and anisotropy jointly control dynamic responses in complex geological media.
Jiajun Shu +8 more
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Energy Science &Engineering, EarlyView.On the basis of core and log data, a Bayesian‐Optimized Random Forest model achieved 92.76% accuracy in classifying tight sandstone reservoirs. A gray relational analysis‐derived evaluation index shows > 80% consistency with actual gas zones. ABSTRACT Tight sandstone gas (TSG), an unconventional oil–gas resource, has heterogeneous reservoirs ...
Yin Yuan +8 more
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A study of radioactive elements of various rocks in Pattani Province with gamma ray spectrometer [PDF]
Songklanakarin Journal of Science and Technology (SJST), 2002 The radioactivity of the three elements, potassium, uranium and thorium, in rocks of various types in Pattani Province was investigated by using a gamma ray spectrometer.
Kaewtubtim, P. +2 more
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Geochemistry, Geophysics, Geosystems, 2014 Sulfides entering subduction zones can play an important role in the release of sulfur and metals to the mantle wedge and contribute to the formation of volcanic arc‐associated ores.
Fabio Giacometti +7 more
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Comparison between 2D and 3D microstructures and implications for metamorphic constraints using a chloritoid–garnet-bearing mica schist [PDF]
European Journal of MineralogyDespite the fact that rock textures depend on the 3D spatial distribution of minerals, our tectono-metamorphic reconstructions are mostly based on a 2D visualisation (i.e. thin sections).
F. Caso +6 more
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Energy Science &Engineering, EarlyView.A comparative study was conducted on gas desorption laws of raw and tectonic coals. The sensitivity of regional and local outburst prediction indexes was compared. Gas content is more sensitive than gas pressure for composite coal seams. K1 can more accurately predict the outburst danger than Δh2 $\Delta {h}_{2}$ in composite coal seams.
Haijun Guo +4 more
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Relationship between Brittleness Index and Crack Initiation Stress Ratio for Different Rock Types
Advances in Civil Engineering, 2020 Brittleness and crack initiation stress (σci) are important rock mechanical properties and intrinsically related to rock deformation and failure. We establish the relationship between σci and uniaxial tensile strength (σt) based on the Griffith stress ...
Juyu Jiang +3 more
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Geological Journal, EarlyView.Charnockites with 2691–2607 Ma magmatic ages from the NMZ show arc‐magmatic geochemical signatures. They correspond to the lower‐crustal equivalent of the Chilimanzi Suite Granite in the Zimbabwe Craton. Lu‐Hf isotopic data of magmatic zircons show negative εHf(t) values (−11.18 to −2.20) with TDMC ages of 3699–3158 Ma, suggesting their protolith ...
Toshiaki Tsunogae +6 more
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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
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