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Mars north polar deposits: stratigraphy, age, and geodynamical response

Science

By:
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DOI: 10.1126/science.1157546

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Abstract

The Shallow Radar (SHARAD) on the Mars Reconnaissance Orbiter has imaged the internal stratigraphy of the north polar layered deposits of Mars. Radar reflections within the deposits reveal a laterally continuous deposition of layers, which typically consist of four packets of finely spaced reflectors separated by homogeneous interpacket regions of nearly pure ice. The packet/interpacket structure can be explained by approximately million-year periodicities in Mars' obliquity or orbital eccentricity. The observed ???100-meter maximum deflection of the underlying substrate in response to the ice load implies that the present-day thickness of an equilibrium elastic lithosphere is greater than 300 kilometers. Alternatively, the response to the load may be in a transient state controlled by mantle viscosity. Both scenarios probably require that Mars has a subchondritic abundance of heat-producing elements.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Mars north polar deposits: stratigraphy, age, and geodynamical response
Series title:
Science
DOI:
10.1126/science.1157546
Volume
320
Issue:
5880
Year Published:
2008
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
First page:
1182
Last page:
1185