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Posibles antiguos océanos en Marte: evidencia de los datos del altímetro láser del orbitador de Marte
J W Head1, H Hiesinger, M A Ivanov
1Department of Geological Sciences, Brown University, Providence, RI 02912, USA.
Science (New York, N.Y.)
|December 11, 1999
Resumen
Los datos de alta resolución sugieren que existe una costa marciana en las tierras bajas del norte. Esta antigua costa, consistente con un gran cuerpo de agua, presenta terrazas y una topografía más suave debajo de ella.
Área de la Ciencia:
- Ciencias planetarias Ciencias planetarias.
- Geología Geología Geología.
- Hidrología Hidrología Hidrología.
Sus antecedentes:
- Las tierras bajas del norte de Marte poseen una topografía compleja.
- Las hipótesis anteriores sugieren que una gran masa de agua existió en la historia media de Marte.
Objetivo del estudio:
- Para analizar datos altimétricos de alta resolución de las tierras bajas del norte de Marte.
- Para evaluar la hipótesis de una antigua costa en esta región.
Principales métodos:
- Utilizó datos altimétricos de alta resolución para mapear la topografía marciana.
- Se analizan las características geológicas y las variaciones topográficas relativas a una línea de contacto propuesta.
Principales resultados:
- Se identificó un contacto geológico distinto que rodea las tierras bajas del norte.
- La altitud del contacto se alinea con una línea equipotencial.
- La topografía por debajo del contacto es significativamente más suave que por encima de ella.
- Amplias terrazas paralelas al contacto en numerosos lugares.
- El volumen de agua estimado se alinea con las estimaciones anteriores para Marte.
Conclusiones:
- El contacto geológico identificado apoya fuertemente la hipótesis de una antigua costa marciana.
- Esta línea costera probablemente demarca un cuerpo de agua grande y estable durante la historia media de Marte.
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