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Actividad acuosa en el Sistema Solar temprano: evidencia isotópica de Sr del meteorito Orgueil CI
J D Macdougall1, G W Lugmair, J F Kerridge
1Scripps Institution of Oceanography, University of California, San Diego, La Jolla 92093, USA.
Nature
|January 19, 1984
Resumen
El carbonato en los meteoritos CI se formó temprano en la historia del Sistema Solar, poco después de la formación del cuerpo progenitor. Sin embargo, algunos sulfatos parecen ser mucho más jóvenes, lo que indica procesos complejos de alteración acuosa a lo largo del tiempo.
Área de la Ciencia:
- Cosmoquímica es la cosmoquímica.
- Ciencias planetarias Ciencias planetarias.
- La meteorítica es la meteorología.
Sus antecedentes:
- Los meteoritos CI son muestras raras de material del Sistema Solar temprano.
- Contienen minerales secundarios formados por alteración acuosa.
- El momento de esta alteración era previamente desconocido.
Objetivo del estudio:
- Para determinar el momento de la alteración acuosa en los meteoritos CI.
- Para investigar la formación de las fases minerales secundarias.
Principales métodos:
- Se midió la composición isotópica del Sr y las relaciones 87Rb/86Sr.
- Analizó las fases de carbonato y sulfato del meteorito Orgueil.
Principales resultados:
- La deposición de carbonato ocurrió simultáneamente o poco después de la formación del cuerpo madre (dentro de 100 millones de años).
- Algunas fases de sulfato de calcio muestran evidencia de formación reciente.
Conclusiones:
- La actividad acuosa temprana fue significativa en los cuerpos progenitores de meteoritos CI.
- También se produjeron eventos acuosos posteriores, que condujeron a la formación de sulfatos.
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