@article{fdi:010044175,
  title = {{S}edimentation and preservation of the {M}iocene {A}tacama {G}ravels in the {P}edernales-{C}hanaral {A}rea, {N}orthern {C}hile : climatic or tectonic control?},
  author = {{N}alpas, {T}hierry and {D}abard, {M}. {P}. and {R}uffet, {G}. and {V}ernon, {A}. and {M}podozis, {C}. and {L}oi, {A}. and {H}{\'e}rail, {G}{\'e}rard},
  editor = {},
  language = {{ENG}},
  abstract = {{I}n recent years, longitudinal changes on the thin/thick-skinned tectonic styles of the {C}entral {A}ndes has been intensively discussed while other studies have considered the role of mass transfers on the unloading of the orogen, and on the stress regime along the plate interface arising from changes on the volume of sediment arriving into the {P}eru-{C}hile trench. {T}he search for paleo-climate records is therefore crucial for our understanding of the history of the {C}entral {A}ndes. {I}n this paper, we focus on the {A}tacama {G}ravels, an extensive blanket of {M}iocene continental deposits filling a {N}eogene paleo-valley system along the southern {A}tacama {D}esert in northern {C}hile. {A}n east-west transect, between {P}edernales and {C}hanaral (26 degrees 30'{S}), enabled us to carry out a sedimentological and tectonic study of the {A}tacama {G}ravels, based on logging and field observations along the {R}io {S}alado canyon. {N}ew {A}r-39-{A}r-40 ages obtained on intercalated and overlying ignimbrites date the beginning of the {A}tacama {G}ravels sedimentation at around the {O}ligocene-{M}iocene boundary and cessation of sedimentation in the {L}ate {M}iocene. {T}hirteen lithofacies, included within five facies associations ({A}1 to {A}5) were identified. {D}epositional environments vary from proximal alluvial fan ({A}1, {A}2) in the {P}recordillera through ephemeral fluvial ({A}3, {A}4) to distal playa lake ({A}5) in the {C}oastal {C}ordillera. {N}o evidences of synsedimentary deformation have been found, showing that the change from sediment removal to sediment preservation cannot be explained by tectonic causes. and climate change appears to be the dominant controlling factor of sediment preservation. {A} progressive change from semi-arid towards hyper-arid climatic conditions during the {M}iocene, led to a reduction on the transport capacity of the fluvial system and sediment preservation along the paleo-valley system formed during the {O}ligocene.},
  keywords = {{A}tacama {G}ravels ; {A}ndes ; {D}epositional environments ; {C}limate ; {D}eformation ; {A}r-39-{A}r-40 dating ; {CHILI} ; {ANDES} ; {ATACAMA}},
  booktitle = {},
  journal = {{T}ectonophysics},
  volume = {459},
  numero = {1-4},
  pages = {161--173},
  ISSN = {0040-1951},
  year = {2008},
  DOI = {10.1016/j.tecto.2007.10.013},
  URL = {https://www.documentation.ird.fr/hor/fdi:010044175},
}