Video Experimental Relacionado
Updated: Jul 12, 2026

07:48
An Externally-Heated Diamond Anvil Cell for Synthesis and Single-Crystal Elasticity Determination of Ice-VII at High Pressure-Temperature Conditions
Published on: June 18, 2020
Resumen
Los diamantes sudafricanos contienen proporciones de helio-3/helio-4. Algunos diamantes muestran proporciones extremadamente altas, lo que sugiere el helio primitivo que ha evolucionado poco desde la formación de la Tierra.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- El análisis de isótopos es un análisis de isótopos.
- Ciencias de la Tierra Ciencias de la Tierra.
Sus antecedentes:
- Los isótopos de helio (helio-3/helio-4) proporcionan una visión de la evolución planetaria.
- Comprender los orígenes del helio es crucial para la ciencia de la Tierra y el sistema solar.
Objetivo del estudio:
- Para analizar la relación isotópica de helio-3/helio-4 en los diamantes sudafricanos.
- Para investigar las implicaciones de las relaciones observadas para el contenido de helio primitivo de la Tierra.
Principales métodos:
- Análisis de la relación isotópica del helio-3 con el helio-4.
- Se tomaron muestras de trece piedras de diamante de minas sudafricanas.
Principales resultados:
- Las proporciones de helio-3/helio-4 variaron significativamente, desde <10(-7) hasta (3.2 ± 0.25) x 10(-4).
- La mayor proporción observada excede la proporción primordial encontrada en los meteoritos.
- La proporción más alta es comparable a las proporciones de helio del tipo solar.
Conclusiones:
- Las proporciones extremadamente altas de helio-3/helio-4 en los diamantes pueden indicar la presencia de helio primitivo.
- Estos hallazgos sugieren una evolución mínima del helio-4 (radiogénico) desde la formación de la Tierra.
- Los diamantes pueden servir como muestras valiosas para estudiar la composición isotópica temprana de la Tierra.
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