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Two-way Valorization of Blast Furnace Slag: Synthesis of Precipitated Calcium Carbonate and Zeolitic Heavy Metal Adsorbent
Published on: February 21, 2017
Formación de carbonatos en el meteorito Tatahouine
J A Barrat1, P Gillet, C Lécuyer
1Université d'Angers, Laboratoire de Géologie, 2 Boulevard Lavoisier, 49045 Angers Cedex, France.
Science (New York, N.Y.)
|May 9, 1998
Resumen
El meteorito de Tatahouine muestra contaminación terrestre, evidenciada por minerales secundarios de calcita y formas en forma de vara que aparecen en las fracturas después de 63 años de exposición a la Tierra. El análisis de isótopos de carbono confirmó que estas características se originaron en la Tierra, no en el meteorito en sí.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- La mineralogía es la Mineralogía.
- Ciencias planetarias Ciencias planetarias.
Sus antecedentes:
- Los meteoritos proporcionan información sobre los materiales y procesos extraterrestres.
- La contaminación terrestre puede alterar la composición de los meteoritos con el tiempo.
- El meteorito Tatahouine cayó en Túnez en el año 1931.
Objetivo del estudio:
- Para investigar la contaminación terrestre en el meteorito Tatahouine.
- Para caracterizar los minerales secundarios y las formas desarrolladas en las fracturas de meteoritos.
- Para determinar el origen de estas características secundarias.
Principales métodos:
- Análisis comparativo de muestras de meteoritos recolectadas en diferentes momentos.
- Examen microscópico de fracturas para el crecimiento de minerales secundarios.
- Análisis de isótopos de carbono (δ13C PDB) de carbonatos en el meteorito y el suelo circundante.
Principales resultados:
- Las muestras de meteoritos de 1931 mostraron fracturas pero no minerales secundarios.
- Las muestras de 1994 exhibieron agregados de calcita y formas en forma de varilla en las fracturas.
- Los valores de isótopos de carbono de los carbonatos secundarios coincidían con los del suelo terrestre, lo que indica el origen de la Tierra.
Conclusiones:
- El meteorito Tatahouine experimentó una significativa contaminación terrestre durante sus 63 años en la Tierra.
- La calcita secundaria y las microestructuras asociadas se formaron después de la caída debido al desgaste terrestre.
- El análisis isotópico es un método confiable para distinguir los materiales extraterrestres de los terrestres en los meteoritos.
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