@article{fdi:010069503,
  title = {{A}cross-arc versus along-arc {S}r-{N}d-{P}b isotope variations in the {E}cuadorian volcanic arc},
  author = {{A}ncellin, {M}. {A}. and {S}amaniego, {P}ablo and {V}lastelic, {I}. and {N}auret, {F}. and {G}announ, {A}. and {H}idalgo, {S}.},
  editor = {},
  language = {{ENG}},
  abstract = {{P}revious studies of the {E}cuadorian arc (1 degrees {N}-2 degrees {S}) have revealed across-arc geochemical trends that are consistent with a decrease in mantle melting and slab dehydration away from the trench. {T}he aim of this work is to evaluate how these processes vary along the arc in response to small-scale changes in the age of the subducted plate, subduction angle, and continental crustal basement. {W}e use an extensive database of 1437 samples containing 71 new analyses, of major and trace elements as well as {S}r-{N}d-{P}b isotopes from {E}cuadorian and {S}outh {C}olombian volcanic centers. {L}arge geochemical variations are found to occur along the {E}cuadorian arc, in particular along the front arc, which encompasses 99% and 71% of the total variations in {P}b-206/{P}b-204 and {S}r-87/{S}r-86 ratios of {Q}uaternary {E}cuadorian volcanics, respectively. {T}he front arc volcanoes also show two major latitudinal trends: (1) the southward increase of {P}b-207/{P}b-204 and decrease of {N}d-143/{N}d-144 reflect more extensive crustal contamination of magma in the southern part (up to 14%); and (2) the increase of {P}b-206/{P}b-204 and decrease of {B}a/{T}h away from similar to 0.5 degrees {S} result from the changing nature of metasomatism in the subarc mantle wedge with the aqueous fluid/siliceous slab melt ratio decreasing away from 0.5 degrees {S}. {S}ubduction of a younger and warmer oceanic crust in the {N}orthern part of the arc might promote slab melting. {C}onversely, the subduction of a colder oceanic crust south of the {G}rijalva {F}racture {Z}one and higher crustal assimilation lead to the reduction of slab contribution in southern part of the arc.},
  keywords = {{EQUATEUR}},
  booktitle = {},
  journal = {{G}eochemistry {G}eophysics {G}eosystems},
  volume = {18},
  numero = {3},
  pages = {1163--1188},
  ISSN = {1525-2027},
  year = {2017},
  DOI = {10.1002/2016gc006679},
  URL = {https://www.documentation.ird.fr/hor/fdi:010069503},
}