North polar trough formation due to in-situ erosion as a source of young ice in mid-latitudinal mantles on Mars

Area of Science:

• Planetary Science
• Geology
• Climate Science

Background:

• The Martian north polar plateau features a prominent clockwise spiral of troughs, a geologically young megastructure.
• A prevailing hypothesis suggests this spiral formed due to poleward migration of troughs.

Purpose of the Study:

• To investigate the formation mechanism of the Martian north polar spiral troughs.
• To determine the origin of the ice within the mid-latitude mantles.

Main Methods:

• Analysis of trough segmentation and internal layered structures.
• Topographical mapping of surface undulations and their relation to troughs.
• Geological interpretation of erosional processes and ice deposition.

Main Results:

• Troughs are segmented into enclosed cells with concentric layers, indicating in-situ erosion.
• Trough segmentation patterns suggest gradual growth transverse to katabatic winds, leading to spiral arrangement.
• Erosion may have supplied up to 25% of mid-latitude icy mantle volume, potentially as recently as 50,000 years ago.

Conclusions:

• The spiral pattern results from in-situ erosion and transverse growth, not solely poleward migration.
• Subsurface troughs confirm the megastructure's stabilization before burial.
• The eroded ice is a potential resource for future human exploration on Mars.