Crustal CO2 contribution to subduction zone degassing recorded through calc-silicate xenoliths in arc lavas
| Autor: | Sean Whitley, Ralf Gertisser, Frances M. Deegan, Ralf Halama, Valentin R. Troll, Katie Preece |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
0301 basic medicine
Geochemistry lcsh:Medicine Volcanology Mantle (geology) Article 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Oceanic crust Xenolith lcsh:Science Calcite geography Multidisciplinary geography.geographical_feature_category Subduction lcsh:R Geokemi Volcanic rock 030104 developmental biology chemistry Volcano Carbonate lcsh:Q 030217 neurology & neurosurgery Geology |
| Zdroj: | Scientific Reports Scientific Reports, Vol 9, Iss 1, Pp 1-11 (2019) |
| Popis: | Interaction between magma and crustal carbonate at active arc volcanoes has recently been proposed as a source of atmospheric CO2, in addition to CO2 released from the mantle and subducted oceanic crust. However, quantitative constraints on efficiency and timing of these processes are poorly established. Here, we present the first in situ carbon and oxygen isotope data of texturally distinct calcite in calc-silicate xenoliths from arc volcanics in a case study from Merapi volcano (Indonesia). Textures and C-O isotopic data provide unique evidence for decarbonation, magma-fluid interaction, and the generation of carbonate melts. We report extremely light δ13CPDB values down to −29.3‰ which are among the lowest reported in magmatic systems so far. Combined with the general paucity of relict calcite, these extremely low values demonstrate highly efficient remobilisation of crustal CO2 over geologically short timescales of thousands of years or less. This rapid release of large volumes of crustal CO2 may impact global carbon cycling. |
| Databáze: | OpenAIRE |
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