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Composición isotópica de oxígeno de la calcita precipitada subglacialmente: posibles implicaciones paleoclimáticas
Science (New York, N.Y.)
|June 16, 1978
Resumen
La calcita subglacial es una calcita subglacial que se encuentra bajo el hielo.
Área de la Ciencia:
- Glaciología y paleoclimatología.
Sus antecedentes:
- El análisis de isótopos de oxígeno es crucial para las reconstrucciones paleoclimáticas.
- Los entornos subglaciales ofrecen archivos únicos de las condiciones climáticas pasadas.
Objetivo del estudio:
- Para investigar si la calcita precipitada subglacialmente puede registrar la firma isotópica de oxígeno del hielo de los glaciares.
- Evaluar el potencial de usar esta calcita para reconstruir las condiciones pasadas de la capa de hielo y el océano.
Principales métodos:
- Análisis isotópico de muestras de calcita recolectadas cerca de un glaciar templado moderno.
- Comparación de los valores del delta de la calcita con los valores del delta de hielo del glaciar.
Principales resultados:
- El delta de la calcita refleja directamente el delta del hielo del glaciar que lo recubre.
- Esta relación se mantiene para la calcita precipitada subglacialmente.
Conclusiones:
- La calcita subglacial es un sustituto confiable para los isótopos de oxígeno del hielo glaciar.
- La antigua calcita se puede utilizar para reconstruir la capa de hielo del Pleistoceno y el delta del océano.
- Este método permite mejorar las estimaciones de la paleotemperatura a partir de datos foraminiferales.
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