@article{fdi:010078986,
  title = {{E}volution of the {E}cuador offshore nonaccretionary-type forearc basin and margin segmentation},
  author = {{H}ernandez, {M}. {J}. and {M}ichaud, {F}. and {C}ollot, {J}ean-{Y}ves and {P}roust, {J}. {N}. and d'{A}cremont, {E}.},
  editor = {},
  language = {{ENG}},
  abstract = {{F}orearc basins have developed along accretionary and nonaccretionary convergent margins. {H}ere, we investigate the evolution of an offshore nonaccretionary-type forearc basin that has developed along the {E}cuadorian convergent margin. {W}e used 2{D}-{M}ultichannel {S}eismic {R}eflection profiles to recognize five seismic units overlying the acoustic basement. {T}he units were dated by correlation with wells and regional stratigraphy. {T}hey recorded the structural evolution of the margin into {N}orth, {C}entral-{N}orth and {C}entral-{S}outh margin segments identified from {G}ravity {F}ree {A}ir {A}nomalies. {I}ntersegment transition zones accommodated deformation related to the margin segmentation, contributing to the development of shelf forearc depocenters. {A}n offshore forearc basin (subunit {L}1a) developed on accreted oceanic terranes during the middle-to-late {E}ocene. {T}he basin was affected by normal faulting during the {O}ligocene to early-middle {M}iocene (subunit {L}1b). {T}his extension stage initiated during the rifting and oblique subduction of the {F}arallon plate beneath the {E}cuador margin. {T}he basin underwent an early-middle {M}iocene uplift outlined by unconformity {U}1 potentially associated with the subduction of the young {N}azca plate, in a less oblique plate convergence environment. {D}uring the early-{P}liocene, the {C}entral-{S}outh margin segment individualized by uplift during the formation of unconformity {U}2. {T}he {M}anta anticline, which developed in the intersegment transition zone, accommodated the segmentation. {T}his event is associated with the arrival of the {C}arnegie ridge in the subduction. {T}he {N}orth segment individualized by uplift during the {P}liocene early-{P}leistocene formation of the {P}edernales structural high, which may coincide with a reactivation of the {C}anande fault. {S}ynchronously, unit {L}3 sediment recorded the subsidence of the {C}entral-{N}orth segment, and strike-slip tectonics in the area of the {J}ama-{B}ahia depocenter. {A} mosaic of middle-to-late {P}leistocene unit {L}5 depocenters that alternate with uplifted zones along the shelf likely recorded the subduction of the topographically irregular {C}arnegie ridge. {T}he study provides a remarkable example of the evolution of a non-accretionary-type forearc basin.},
  keywords = {{C}onvergent margin ; {N}onaccretionary forearc basin ; {E}cuador ; {M}ultichannel ; seismic reflection ; {EQUATEUR} ; {PACIFIQUE}},
  booktitle = {},
  journal = {{T}ectonophysics},
  volume = {781},
  numero = {},
  pages = {art. 228374 [ p.]},
  ISSN = {0040-1951},
  year = {2020},
  DOI = {10.1016/j.tecto.2020.228374},
  URL = {https://www.documentation.ird.fr/hor/fdi:010078986},
}