The light lithophile (Li, Be and B) and halogen (F, Cl) elements are powerful tracers of fluid transfer, due to their mobility during high temperature hydrothermal processes and metamorphic devolatilization, as documented by their very high concentrations detected in altered oceanic rocks -as a result of interactions with hydrothermal fluids- relative to their low contents in mantle reservoirs. Moreover, although a great deal of studies have been carried out on Li, Be, B, F (and Cl) in whole rock and rock-forming minerals of altered rocks from divergent and convergent plate margins, an inventory of such trace elements in mineral phases from altered Icelandic oceanic crust is still incomplete and requires thorough constraints and detailed monitoring. A micro-analytical study of light and volatile elements in single mineral phases is of importance when studying the Reykjanes geothermal system in SW Iceland, collaborating in the Iceland Deep Drilling Project (IDDP) drilling. Here we report the results of in-situ EMPA and SIMS investigations on 10 basaltic rock samples of altered magmatic (plagioclase and clinopyroxene) and hydrothermal phases (amphibole and epidote). The samples are from drill cuttings at different depths, ranging from 400-3000 m from the well RN-17. To authors' knowledge, this data on light and volatile elements, i.e., Li, Be, B and F is the first in the literature on single mineral phases from the Reykjanes system, and complete our research on light elements begun two years ago on this geothermal field. Our study benefited from the use of detailed optical and SEM investigations; from ICP-MS on Li, and ID analysis on B on the whole rock; from TIMS on B isotope ratios. The analytical result and its significance will be described at the EMAS 2009 workshop.
SIMS study of volatile elements in mineral phases from well RN-17 (Reykjanes Peninsula, SW Iceland)
OTTOLINI L;TONARINI S;GIANELLI G;
2009
Abstract
The light lithophile (Li, Be and B) and halogen (F, Cl) elements are powerful tracers of fluid transfer, due to their mobility during high temperature hydrothermal processes and metamorphic devolatilization, as documented by their very high concentrations detected in altered oceanic rocks -as a result of interactions with hydrothermal fluids- relative to their low contents in mantle reservoirs. Moreover, although a great deal of studies have been carried out on Li, Be, B, F (and Cl) in whole rock and rock-forming minerals of altered rocks from divergent and convergent plate margins, an inventory of such trace elements in mineral phases from altered Icelandic oceanic crust is still incomplete and requires thorough constraints and detailed monitoring. A micro-analytical study of light and volatile elements in single mineral phases is of importance when studying the Reykjanes geothermal system in SW Iceland, collaborating in the Iceland Deep Drilling Project (IDDP) drilling. Here we report the results of in-situ EMPA and SIMS investigations on 10 basaltic rock samples of altered magmatic (plagioclase and clinopyroxene) and hydrothermal phases (amphibole and epidote). The samples are from drill cuttings at different depths, ranging from 400-3000 m from the well RN-17. To authors' knowledge, this data on light and volatile elements, i.e., Li, Be, B and F is the first in the literature on single mineral phases from the Reykjanes system, and complete our research on light elements begun two years ago on this geothermal field. Our study benefited from the use of detailed optical and SEM investigations; from ICP-MS on Li, and ID analysis on B on the whole rock; from TIMS on B isotope ratios. The analytical result and its significance will be described at the EMAS 2009 workshop.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
