The mineralogy and geochemistry of quartz-tourmaline schlieren in the granites of the Primorsky Complex, Western Baikal Region

التفاصيل البيبلوغرافية
العنوان: The mineralogy and geochemistry of quartz-tourmaline schlieren in the granites of the Primorsky Complex, Western Baikal Region
المؤلفون: S. V. Kanakin, V. B. Savel’eva, E. P. Bazarova
المصدر: Geology of Ore Deposits. 56:617-628
بيانات النشر: Pleiades Publishing Ltd, 2014.
سنة النشر: 2014
مصطلحات موضوعية: Tourmaline, Muscovite, Geochemistry, Mineralogy, Geology, engineering.material, Feldspar, Geochemistry and Petrology, visual_art, Schlieren, Monazite, engineering, visual_art.visual_art_medium, Economic Geology, Quartz, Ilmenite, Zircon
الوصف: Quartz-tourmaline schlieren have been found within rapakivi-like granites of the Early Proterozoic Primorsky Complex in the Western Baikal Region. These rocks are biotite leucogranites with normal alkalinity (A/CNK = 1.00–1.04); a high iron mole fraction (92–95%); a K2O/Na2O value of about 2.0; relatively high F, Li, Rb, Cs, Sn, Pb, Th, and U contents; and low Ba, Sr, Eu, Zn, Sc, and V contents. The schlieren composed of quartz and tourmaline with relics of feldspar also contain fluorite, rare muscovite, chlorite, and accessory rutile, ilmenite, zircon, monazite, xenotime, and bastnasite. B2O3 and F contents in the schlieren are 2.29–2.63 and 0.30–0.47 wt %, respectively. Fe2O3 (4.8–5.4 wt %), F, and H2O contents are higher in these schlieren than in the host granite, while SiO2, CaO, Na2O, K2O, and P2O5 contents are lower than in host rocks. K2O/Na2O values decrease in the schlieren down to 0.4. Enrichment of the schlieren in Fe and other ore elements (Zn, Co, Cu, Sn, etc.), together with B, F, H2O, and Na, suggests that they crystallized from fluid-saturated melt segregated from aluminosilicate melt in the apical part of a shallow-seated intrusion. The formation of tourmaline may be related to the interaction of the fluid with feldspars in the crystallizing granites; it was accompanied by a separation of fluid F-CO2. Quartz precipitated at the next stage, due to the acidic character of the aqueous fluid. In general, the relationships of minerals in the schlieren indicate distinct fractionation of LREE, HREE, and Y in the fluid-saturated melt.
تدمد: 1555-6476
1075-7015
DOI: 10.1134/s1075701514080091
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_________::89503c793031c955d958ff9ae60cbcbe
https://doi.org/10.1134/s1075701514080091
Rights: CLOSED
رقم الانضمام: edsair.doi...........89503c793031c955d958ff9ae60cbcbe
قاعدة البيانات: OpenAIRE
الوصف
تدمد:15556476
10757015
DOI:10.1134/s1075701514080091