@article{fdi:010041422,
  title = {{C}retaceous alkaline intra-plate magmatism in the {E}cuadorian {O}riente {B}asin : geochemical, geochronological and tectonic evidence},
  author = {{B}arragan, {R}. and {B}aby, {P}atrice and {D}uncan, {R}.},
  editor = {},
  language = {{ENG}},
  abstract = {{S}mall volumes of {C}retaceous alkaline basaltic magmas have been identified in the sedimentary infill of the {E}cuadorian {O}riente foreland basin. {T}hey are characterized by a restricted range of compositional variation, low {LILE}/{HFSE} ratios and {S}r-{N}d isotope values within the range of oceanic island basalts ({OIB}). {R}eflection seismic data show that a pre-existing {NNE}-{SSW} {T}riassic and {J}urassic rift controls the location and occurrence of these alkaline eruptive sites. {R}adiometric ages (4(40){A}r-{A}r-39, incremental heating method) and the biostratigraphic record of their surrounding sediments indicate a {NNE}-{SSW} systematic age variation for the emplacement of this alkaline volcanism: from {A}lbian (110 +/- 5.2 {M}a) in the northern part of the {O}riente {B}asin, to {C}ampanian (82.2 +/- 2.0 {M}a) in the west-central part. {T}he geochemical, geochronological and tectonic evidences suggest that asthenospheric mantle has upwelled and migrated to the {SSW}, into the region underlying the pre-existing {T}riassic and {J}urassic rift (thin-spot?). {W}e propose that subduction was abandoned, subsequent to the accretion of allochthonous terranes onto the {E}cuadorian and {C}olombian margin in the latest {J}urassic-earliest {C}retaceous, causing the relict slab material, corresponding to the eastwards-directed leading plate, to roll-back. {U}nmodified asthenospheric mantle migrated into the region previously occupied by the slab. {T}his resulted in partial melting and the release of magmatic material to the surface in the northern part of the {O}riente {B}asin since at least {A}ptian times. {T}hen, magmatism migrated along the {SSW}-trending {C}entral {W}rench {C}orridor of the {O}riente {B}asin during the {U}pper {C}retaceous, probably as a consequence of the lateral propagation of the transpressive inversion of the {T}riassic-{J}urassic rift. {E}ventually, the {L}ate {C}retaceous east-dipping {A}ndean subduction system was renewed farther west, and the development of the compressional retro-foreland {O}riente {B}asin system halted the {C}retaceous alkaline magmatic activity. (c) 2005 {E}lsevier {B}.{V}.. {A}ll rights reserved.},
  keywords = {{N}orthern {A}ndes ; {E}cuador ; {O}riente {B}asin ; alkaline magmatism ; {C}retaceous ; roll back ; transpressive inversion},
  booktitle = {},
  journal = {{E}arth and {P}lanetary {S}cience {L}etters},
  volume = {236},
  numero = {3-4},
  pages = {670--690},
  ISSN = {0012-821{X}},
  year = {2005},
  DOI = {10.1016/j.epsl.2005.03.016},
  URL = {https://www.documentation.ird.fr/hor/fdi:010041422},
}