@article{fdi:010088662,
  title = {{I}n situ probing of the present-day zircon-bearing magma chamber at {K}rafla, {N}ortheastern {I}celand},
  author = {{B}orisova, {A}. {Y}. and {M}elnik, {O}. {E}. and {G}aborit, {N}. and {B}indeman, {I}. {N}. and {T}raillou, {T}. and {R}affarin, {M}. and {S}tefánsson, {A}. and {L}aurent, {O}. and {L}eisen, {M}athieu and {L}lovet, {X}. and de {P}arseval, {P}. and {P}roietti, {A}. and {T}ait, {S}.},
  editor = {},
  language = {{ENG}},
  abstract = {{A}ctive felsic magmatism has been rarely probed in situ by drilling but one recent exception is quenched rhyolite sampled during the 2009 {I}celand {D}eep {D}rilling {P}roject ({IDDP}). {W}e report finding of rare zircons of up to similar to 100 mu m in size in rhyolite glasses from the {IDDP}-1 well products and the host 1724 {AD} {V}iti granophyres. {T}he applied {SHRIMP} {U}-{T}h dating for both the {IDDP} and the {V}iti granophyre zircons gives zero-age (+/- 2 kyr), and therefore suggests that the {IDDP}-1 zircons have crystallized from an active magma intrusion rather than due to the 20-80 ka post-caldera magmatic episodes recorded by nearby domes and ridges. {T}i-in-zircon geothermometer for {V}iti granophyre reveals zircon crystallization temperatures similar to 800 degrees {C}-900 degrees {C}, whereas {IDDP}-1 rhyolite zircon cores show {T}i content higher than 100 ppm, corresponding to temperatures up to similar to 1,100 degrees {C} according to the {T}i-in-zircon thermometer. {A}ccording to our thermochemical model at such elevated temperatures as 1,100 degrees {C}, rhyolitic magma cannot be saturated with zircon and zircon crystallization is not possible. {W}e explain this controversy by either kinetic effects or non-ideal {T}i incorporation into growing zircons at low pressures that start to grow from nucleus at temperatures similar to 930 degrees {C}. {H}igh temperatures recorded by {IDDP}-1 zircon together with an occurrence of baddeleyite require that the rhyolite magma formed by partial melting of the host granophyre due to basaltic magma intrusion. {Z}r concentration profiles in glass around zircons are flat, suggesting residence in rhyolitic melt for >4 years. {I}n our thermochemical modeling, three scenarios are considered. {T}he host felsite rocks are intruded by: 1) a basaltic sill, 2) rhyolite magma 3) rhyolite sill connected to a deeper magmatic system. {B}ased on the solution of the heat conduction equation accounting for the release of latent heat and effective thermal conductivity, these data confirm that the rhyolite magma could be produced by felsic crust melting as a result of injection of a basaltic or rhyolite sill during the {K}rafla {F}ires eruption (1975 {AD}).},
  keywords = {{I}celand {D}eep {D}rilling {P}roject ; {IDDP}-1 sample ; zircon ; rhyolite magma ; genesis ; {U}-{T}h age ; granophyre ; melting ; thermochemical modeling ; {ICELANDE}},
  booktitle = {},
  journal = {{F}rontiers in {E}arth {S}cience},
  volume = {11},
  numero = {},
  pages = {1307303 [12 p.]},
  year = {2023},
  DOI = {10.3389/feart.2023.1307303},
  URL = {https://www.documentation.ird.fr/hor/fdi:010088662},
}