The boundary between South America and Scotia plates was established during Neo-gene times when a wrench tectonic regime was developed along the central area ofTierra del Fuego. This boundary includes the Magallanes–Fagnano fault system: aregional diffuse deformation zone, which involves the development of the satelliteYehuin–Chepelmut fault zone and a series of pull-apart basins overprinting theFuegian fold and thrust belt. The analysis of regional seismic lines allowed to recon-struct and recognize the structure of the external fold and thrust belt. The interpretedstructures were integrated into a regional transect and a 3D block diagram that dis-play the different structural domains and, mainly, the wrench deformation associatedwith the Magallanes–Fagnano fault system. Geophysical data from gravity and mag-netic anomaly maps provided further support for the location and development ofthe pull-apart basins along the plate boundary. The deformation of the external foldand thrust belt is characterized by an imbricated fan system with a Paleogene detach-ment surface, which was later cut across by the Yehuin–Chepelmut fault zone andthe Magallanes–Fagnano fault system
The central Fuegian fold and thrust belt in Tierra del Fuego:Strike-slip tectonics superimposed onto compressionaldeformation
Marco Menichetti;
2020
Abstract
The boundary between South America and Scotia plates was established during Neo-gene times when a wrench tectonic regime was developed along the central area ofTierra del Fuego. This boundary includes the Magallanes–Fagnano fault system: aregional diffuse deformation zone, which involves the development of the satelliteYehuin–Chepelmut fault zone and a series of pull-apart basins overprinting theFuegian fold and thrust belt. The analysis of regional seismic lines allowed to recon-struct and recognize the structure of the external fold and thrust belt. The interpretedstructures were integrated into a regional transect and a 3D block diagram that dis-play the different structural domains and, mainly, the wrench deformation associatedwith the Magallanes–Fagnano fault system. Geophysical data from gravity and mag-netic anomaly maps provided further support for the location and development ofthe pull-apart basins along the plate boundary. The deformation of the external foldand thrust belt is characterized by an imbricated fan system with a Paleogene detach-ment surface, which was later cut across by the Yehuin–Chepelmut fault zone andthe Magallanes–Fagnano fault systemI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
