Artículo
Structure and evolution of volcanic plumbing systems in fold-and-thrust belts: A case study of the Cerro Negro de Tricao Malal, Neuquén Province, Argentina
Fecha de publicación:
09/2015
Editorial:
Geological Society of America
Revista:
Geological Society Of America Bulletin
ISSN:
0016-7606
e-ISSN:
1943-2674
Idioma:
Inglés
Tipo de recurso:
Artículo publicado
Clasificación temática:
Resumen
Magma ascent and emplacement in compressional tectonic settings remain poorly understood. Geophysical studies show that volcanic plumbing systems in compressional environments are vertically partitioned into a deep level subject to regional compression and a shallow level subject to local extension. Such vertical partitioning has also been documented for the plumbing systems of mud volcanoes, implying common, yet unresolved, underlying processes. In order to better constrain the mechanisms governing this depth partitioning of emplacement mechanisms, we studied the structure and evolution of the Cerro Negro intrusive complex emplaced in the Chos Malal fold-and-thrust belt in the foothills of the Neuquén Andes, Argentina. The Cerro Negro intrusive complex consists of sills and N-S–striking dikes that crosscut the sills. The most prominent structures in the study area are N-S–trending folds, and both E- and W-vergent thrusts. We provide new U-Pb ages of 11.63 ± 0.20 Ma and 11.58 ± 0.18 Ma for sills and 11.55 ± 0.06 Ma for a dike, which show that the Cerro Negro intrusive complex was emplaced in a short period of time. Our ages and field observations demonstrate that the emplacement of the Cerro Negro intrusive complex was coeval with the tectonic development of the Chos Malal fold-and-thrust belt. This implies that the dikes were emplaced perpendicular to the main shortening direction. The systematic locations of the dikes at the anticlinal hinges suggest that their emplacement was controlled by local, shallow stresses related to outer-arc stretching at the anticlinal hinge. We conclude that folding-related outer-arc stretching is one mechanism responsible for the vertical partitioning of igneous plumbing systems in compressional tectonic settings.
Palabras clave:
Neuquén - Argentina
,
Volcaninc
,
Cerro Negro
,
Tricao Malal
Archivos asociados
Licencia
Identificadores
Colecciones
Articulos(MACNBR)
Articulos de MUSEO ARG.DE CS.NAT "BERNARDINO RIVADAVIA"
Articulos de MUSEO ARG.DE CS.NAT "BERNARDINO RIVADAVIA"
Citación
Gürer, Derya; Galland, Olivier; Fernando Corfu; Leanza, Hector Armando; Sassier, Caroline; Structure and evolution of volcanic plumbing systems in fold-and-thrust belts: A case study of the Cerro Negro de Tricao Malal, Neuquén Province, Argentina; Geological Society of America; Geological Society Of America Bulletin; 128; 1-2; 9-2015; 315-331
Compartir
Altmétricas