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Elevación constante del sur del Tíbet durante los últimos 15 millones de años
Robert A Spicer1, Nigel B W Harris, Mike Widdowson
1Department of Earth Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK. R.A.Spicer@open.ac.uk
Nature
|February 7, 2003
Resumen
Las hojas fósiles del Tíbet indican la meseta del sur del Tíbet.
Área de la Ciencia:
- Paleoclimatología Paleoclimatología
- Geología Geología Geología.
- Ciencias del clima Ciencias del clima Ciencias del clima
Sus antecedentes:
- La elevación de la meseta tibetana influye en el clima global y los monzones.
- Los modelos anteriores carecen de confirmación observacional de la historia de elevación.
Objetivo del estudio:
- Para reconstruir la historia de la elevación de la meseta del sur del Tíbet.
- Para probar modelos de engrosamiento litosférico utilizando datos paleobotánicos.
Principales métodos:
- Análisis de ensamblajes fósiles de hojas de la cuenca de Namling (aprox. 15 millones de años de edad).
- Modelado numérico de la circulación general para estimar las paleotemperaturas y la energía estática húmeda.
- Reconstrucción de la elevación de la cuenca basada en proxies climáticas.
Principales resultados:
- Se analizaron hojas fósiles fechadas hace ~15 millones de años.
- La elevación estimada de la cuenca de Namling hace 15 millones de años fue de ~ 4.600 metros.
- Esta elevación es comparable a la altitud actual.
Conclusiones:
- La elevación de la meseta del sur del Tíbet probablemente se ha mantenido estable durante los últimos 15 millones de años.
- Este hallazgo desafía algunos modelos de elevación continua de la meseta.
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