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Las capas de hielo subterráneas expuestas en las latitudes medias de Marte
Colin M Dundas1, Ali M Bramson2, Lujendra Ojha3
1Astrogeology Science Center, U.S. Geological Survey, 2255 N. Gemini Drive, Flagstaff, AZ 86001, USA.
Science (New York, N.Y.)
|January 13, 2018
Resumen
Las latitudes medias marcianas contienen depósitos gruesos y poco profundos de hielo de agua subterráneo. La erosión expone estas capas ricas en hielo, haciendo que las escarpas se retiren debido a la sublimación, revelando Marte
Área de la Ciencia:
- Ciencias planetarias
- Geología
- Ciencias del clima
Sus antecedentes:
- Las amplias regiones de las latitudes medias marcianas están cubiertas por mantos gruesos y lisos.
- La erosión de estos mantos forma escarpas, exponiendo la estructura interna del depósito.
- El hielo subterráneo es un recurso clave e indicador del clima pasado en Marte.
Objetivo del estudio:
- Para investigar la composición y estructura de los depósitos de hielo de latitudes medias de Marte.
- Comprender los procesos que afectan a los depósitos de hielo expuestos, como la sublimación.
- Evaluar el potencial de estos depósitos como archivos del clima pasado.
Principales métodos:
- Investigación de campo de ocho lugares en las latitudes medias de Marte.
- Análisis del espesor, la profundidad y las características estructurales del depósito expuesto.
- Observación del retroceso activo de las escamas y los procesos de sublimación asociados.
Principales resultados:
- Los depósitos expuestos contienen hielo de agua de más de 100 metros de espesor.
- El hielo se encuentra desde profundidades tan superficiales como 1-2 metros debajo de la superficie.
- Las escarpas que se retiran activamente son impulsadas por la sublimación del hielo expuesto.
Conclusiones:
- Los depósitos de hielo marciano probablemente se formaron a partir de nevadas compactadas durante períodos de alta oblicuidad.
- Estos depósitos de hielo masivos, fracturados y en capas representan importantes archivos climáticos.
- La estructura vertical de estos depósitos puede preservar un registro de la deposición de hielo y el pasado clima marciano.
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