Results 31 to 40 of about 47,799 (141)
Journal of Economic Geology, 2021 Introduction Phosphorites are marine sediments of biogenic origin containing 15–20 wt% P2O5 and between 50 and 120 ppm U (Boggs, 2009; Tzifas et al., 2014; Zarasvandi et al., 2019).
Alireza Zarasvandi +3 more
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Geosciences, 2017 Phosphates from the Martian shergottite NWA 2975 were used to obtain insights into the source and subsequence differentiation of the melt/melts.
Ewa Słaby +5 more
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Geochemistry of apatite in various felsic rocks of the Piranshahr plutonic complex: an approach to investigate magmatic evolution [PDF]
علوم زمین خوارزمی, 2023 The felsic intrusive rocks in the Piranshahr plutonic complex consist of three groups: syenite, nepheline-syenite, and alkali-feldspar granite. They are co-genetic and formed approximately 40 million years ago.
Seyed Ali Mazhari, Kwan-Nang Pang
doaj
The composition of apatite in the Archean Siilinjärvi glimmerite-carbonatite complex in eastern Finland [PDF]
Bulletin of the Geological Society of FinlandWe present a geochemical dataset and cathodoluminescence images of apatite from the Neoarchean (2610 Ma) glimmerite-carbonatite rocks from the Siilinjärvi complex, Eastern Finland. The subhedral, tapered prismatic grains are compositionally fluorapatite,
Seppo Karvinen +3 more
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Geology and Geochemistry of the Early Proterozoic Kortejärvi and Laivajoki Carbonatites, Central Fennoscandian Shield, Finland [PDF]
Bulletin of the Geological Society of Finland, 1997 This paper provides for the first time extensive petrological, mineralogical and geochemical data on the early Proterozoic Kortejärvi and Laivajoki carbonatites, northern Finland, which form metamorphosed and highly strained bodies 2 and 4 km long within
J. Nykänen, K. Laajoki, J. Karhu
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Известия Томского политехнического университета: Инжиниринг георесурсов, 2018 The relevance of the work is caused by appearance of thermodynamic data on heavy REE phosphates, bastnesite and parizite, as well as experimental data on stability of lanthanides sulfate complexes and yttrium fluorine complexes in solutions.
Galina Petrovna Shironosova +1 more
doaj +2 more sources
REE minerals at the Songwe Hill carbonatite, Malawi: HREE-enrichment in late-stage apatite [PDF]
, 2016 Compared to all published data from carbonatites and granitoids, the fluorapatite compositions in the Songwe Hill carbonatite, determined by EPMA and LA ICP-MS, have the highest heavy (H)REE concentration of any carbonatite apatite described so far.
S Broom-Fendley (21855821) +4 more
core +3 more sources
Speculations Linking Monazite Compositions to Origin: Llallagua Tin Ore Deposit (Bolivia)
Resources, 2017 Monazite [(Ce,Th)PO4] from the Llallagua tin ore deposit in Bolivia is characterized by low radiogenic element contents. Previously reported field evidence and mineral associations suggest the mineral formed via direct precipitation from hydrothermal ...
Elizabeth J. Catlos, Nathan R. Miller
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Geological Journal, EarlyView.U–Pb isotope and trace element geochemistry of apatite from carbonatites of Peshawar Plain Alkaline Igneous Province, western Himalaya shows Permo‐Carboniferous magmatism, an additional magmatic pulse during Cretaceous, and post‐magmatic hydrothermal/metasomatism during Oligocene. ABSTRACT U–Pb isotope and trace element geochemistry of apatite combined
Mehboob ur Rashid +9 more
wiley +1 more source
Quantification of Sulfur Speciation in Apatites: Comparison of the XAS, XPS and EPMA Techniques
Geostandards and Geoanalytical Research, EarlyView.Key Points Sulfur speciation in apatites has been determined by S K‐edge X‐ray absorption near‐edge structure (XANES) spectroscopy, S 2p X‐ray photoelectron spectroscopy (XPS) and electron probe microanalysis (EPMA). XANES provides the most sensitive and accurate quantification of sulfur speciation.
Yuzhou Feng +8 more
wiley +1 more source