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Mayor reorganización de la placa australiano-antártica en la curva de tiempo Hawaiano-Emperador
J M Whittaker1, R D Müller, G Leitchenkov
1EarthByte Group, School of Geosciences, University of Sydney, Sydney 2006, Australia. j.whittaker@geosci.usyd.edu.au
Science (New York, N.Y.)
|October 6, 2007
Resumen
Las reconstrucciones tectónicas de placas revelan una importante reorganización hace 50 millones de años, lo que explica la curva Hawaiano-Emperador. Este evento involucró a Australia, la Antártida y los desplazamientos de placas del Pacífico, resolviendo los problemas de ajuste continental.
Área de la Ciencia:
- La geofísica es la geofísica.
- La tectónica de placas es la tectónica de placas.
- La paleogeografía es la paleogeografía.
Sus antecedentes:
- La curva de la cadena de montaña submarina Hawaiian-Emperor se atribuye a una reorganización del manto de placas hace ~50 millones de años.
- Las hipótesis anteriores carecían de soporte para eventos contemporáneos de la placa circumpacífica.
Objetivo del estudio:
- Para investigar la causa de la curva de la cadena de montaña submarina Hawaiano-Emperador.
- Para identificar eventos tectónicos de placas contemporáneos que explican la curva observada.
Principales métodos:
- Desarrolló nuevas reconstrucciones de placas para Australia y la Antártida.
- Reconstrucciones revisadas del fondo marino del Océano Pacífico.
Principales resultados:
- Identificó una importante reorganización de placas entre Australia y la Antártida de hace 50 a 53 millones de años.
- Vinculó esta reorganización a la subducción de la cresta de extensión Pacífico-Izanagi.
- Se propuso el inicio de la subducción Marianas/Tonga-Kermadec como una causa potencial.
Conclusiones:
- La reorganización de la placa identificada proporciona un mecanismo para la curva de la cadena de montaña submarina Hawaiano-Emperador.
- Estas reconstrucciones resuelven problemas de ajuste continental de larga data.
- Mejora de las restricciones en el movimiento Este-Oeste de la Antártida y el cierre del circuito global de placas.
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