Publications des scientifiques de l'IRD

Rossel K., Aguilar G., Salazar E., Martinod J., Carretier Sébastien, Pinto L., Cabre A. (2018). Chronology of Chilean Frontal Cordillera building from geochronological, stratigraphic and geomorphological data insights from Miocene intramontane-basin deposits. Basin Research, 30 (S1), p. 289-310. ISSN 0950-091X.

Titre du document
Chronology of Chilean Frontal Cordillera building from geochronological, stratigraphic and geomorphological data insights from Miocene intramontane-basin deposits
Année de publication
2018
Type de document
Article référencé dans le Web of Science WOS:000419873300016
Auteurs
Rossel K., Aguilar G., Salazar E., Martinod J., Carretier Sébastien, Pinto L., Cabre A.
Source
Basin Research, 2018, 30 (S1), p. 289-310 ISSN 0950-091X
The Chilean Frontal Cordillera, near 28 degrees 45S, provides a remarkable example to explore the evolution of the Central Andes; this area provides conspicuous pediment surfaces and continental deposits, which allowed us to analyse the timing and propagation of deformation which controlled the Andes building during the Cenozoic using structural, geomorphological, sedimentological, stratigraphic and geochronological data. The study area is characterized by outcrops of the Cerro del Burro Gravels, a continental deposit which is surrounded by four morphostructural mountain systems. Based on a 46Ma tuff affected by a syncline, which is sealed by a 44Ma tuff, we recognized an Eocene fault activity that contributed to the uplift of the western and northern systems, which have remained inactive during the last 44Ma. The deformed lithologies during the last pulse of activity of the western fault and the youngest lithology carved by pediment processes (21Ma) indicate a pediment surface developed during the Late Eocene and Oligocene. This pediment extended below the Cerro del Burro Gravels associated to a base level which drained to the east. We also recognized Miocene fault activity that played a main role in the uplift of the eastern and southern systems. Geochronological, stratigraphic and geomorphological data suggest a first pulse of fault activity between 19 and 13Ma, which interrupted the pedimentation processes, developed an intramontane depocenter, and forced the accumulation of the Laguna Grande Succession in an alluvial-braided fluvial environment. After 13Ma, an erosive event evidenced by the incision of valleys, resulted after the change in the extension and configuration of the hydric network.
Plan de classement
Géologie et formations superficielles [064]
Description Géographique
CHILI ; ANDES
Localisation
Fonds IRD [F B010071990]
Identifiant IRD
fdi:010071990
Contact