Buried Ice and Sand Caps at the North Pole of Mars: Revealing a Record of Climate Change in the Cavi Unit With SHARAD
Name:
Nerozzi_et_al-2019-Geophysical ...
Size:
1.818Mb
Format:
PDF
Description:
Final Published Version
Affiliation
Univ Arizona, Dept Planetary Sci, Lunar & Planetary LabIssue Date
2019-05-22
Metadata
Show full item recordPublisher
AMER GEOPHYSICAL UNIONCitation
Nerozzi, S., & Holt, J. W. (2019). Buried ice and sand caps at the north pole of Mars: Revealing a record of climate change in the cavi unit with SHARAD. Geophysical Research Letters, 46, 7278–7286. https://doi.org/10.1029/2019GL082114Journal
GEOPHYSICAL RESEARCH LETTERSRights
Copyright © 2019. The Authors. This is an open access article under the terms of the Creative Commons Attribution‐Non Commercial‐No Derivs License.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
The cavi unit at the north pole of Mars is a deposit of aeolian sand and water ice underlying the Late Amazonian north polar layered deposits. Its strata of Middle to Late Amazonian age record wind patterns and past climate. The Mars Reconnaissance Orbiter Shallow Radar (SHARAD) reveals extensive internal and basal layering within the cavi unit, allowing us to determine its general structure and relative permittivity. Assuming a basalt composition for the sand (ε′ = 8.8), results indicate that cavi contains an average ice fraction between 62% in Olympia Planum and 88% in its northern reaches beneath the north polar layered deposits and thus represents one of the largest water reservoirs on the planet. Internal reflectors indicate vertical variability in composition, likely in the form of alternating ice and sand layers. The ice layers may be remnants of former polar caps and thus represent a unique record of climate cycles predating the north polar layered deposits.Note
Open access articleISSN
0094-8276Version
Final published versionSponsors
NASA Mars Data Analysis Program [NNX15AM52G]; Landmark Software and Services, a Halliburton Companyae974a485f413a2113503eed53cd6c53
10.1029/2019gl082114
Scopus Count
Collections
Except where otherwise noted, this item's license is described as Copyright © 2019. The Authors. This is an open access article under the terms of the Creative Commons Attribution‐Non Commercial‐No Derivs License.