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Magmatismo contemporáneo a gran escala en los cratones del Kalahari y Laurentian durante el ensamblaje de Rodinia
Richard E Hanson1, James L Crowley, Samuel A Bowring
1Department of Geology, Texas Christian University, Fort Worth, TX 76129, USA. r.hanson@tcu.edu
Science (New York, N.Y.)
|April 24, 2004
Resumen
Grandes provincias ígneas en América del Norte y el sur de África, que datan de hace 1.100 millones de años, sugieren un solo evento durante Rodinia.
Área de la Ciencia:
- Geología Geología Geología.
- La geofísica es la geofísica.
- El paleomagnetismo es el paleomagnetismo.
Sus antecedentes:
- El magmatismo intraplaquetario está vinculado a las plumas del manto.
- El supercontinente Rodinia se formó hace aproximadamente 1.100 millones de años.
Objetivo del estudio:
- Para investigar el momento y la extensión del magmatismo intraplate durante el ensamblaje de Rodinia.
- Para determinar si los eventos magmáticos en diferentes cratones fueron contemporáneos.
Principales métodos:
- Datación radiométrica de las rocas ígneas.
- Análisis paleomagnético para determinar la polaridad magnética cron.
Principales resultados:
- El magmatismo intraplate se produjo en el cratón del Kalahari (África meridional) desde hace 1106 a 1112 millones de años.
- Este magmatismo ocurrió durante el mismo cronograma de polaridad magnética que eventos similares en el cratón norteamericano.
- Los eventos magmáticos cubrieron un área de dos millones de kilómetros cuadrados a través de ambos cratones.
Conclusiones:
- Se deduce que los eventos magmáticos en el sur de África y América del Norte son parte de una sola gran provincia ígnea.
- El extendido magmatismo intraplate durante el ensamblaje de los supercontinentes indica que las subidas del manto pueden ocurrir independientemente del ciclo de los supercontinentes.
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