Decametre-thick remnant glacial ice deposits on Mars

Research areas:

• Surfaces planétaires (2011 - 2016)

Year:

2014

Authors:

• Susan Conway
• Matthew R. Balme

Journal:

Geophysical Research Letters

Volume:

41

Number:

15

Pages:

5402-5409

BibTex:

@article{conway_decametre-thick_2014, author = "Susan Conway and Matthew R. Balme", abstract = "On Mars a smooth, draping unit - the “Latitude Dependant Mantle” (LDM) believed to comprise meters-thick layers of dust and ice - extends from the mid-latitudes to the poles, covering at least 23\% of the surface [Kreslavsky and Head, 2000; Mustard et al., 2001]. We show that the LDM can be 30 m deep on pole-facing crater walls and, by measuring the erosional and depositional volumes of small gullies that incise these LDM deposits, we show that it must contain between 46\% and 95\% ice by volume. Extrapolating to a global scale, these deposits account for {\textasciitilde}104 km3 of near-surface ice, doubling previous LDM volume estimates [Kreslavsky and Head, 2002]. Thick LDM deposits can be emplaced during the many orbital variation-driven climate excursions [Jakosky and Carr, 1985] that occurred during the Amazonian. We suggest LDM deposits are similar to ice-sheets composed of massive ice with a surface lag.", doi = "10.1002/2014GL060314", extra = "PICL", journal = "Geophysical Research Letters", number = "15", pages = "5402--5409", title = "{D}ecametre-thick remnant glacial ice deposits on {M}ars", volume = "41", year = "2014", }

Abstract:

On Mars a smooth, draping unit - the “Latitude Dependant Mantle” (LDM) believed to comprise meters-thick layers of dust and ice - extends from the mid-latitudes to the poles, covering at least 23\% of the surface [Kreslavsky and Head, 2000; Mustard et al., 2001]. We show that the LDM can be 30 m deep on pole-facing crater walls and, by measuring the erosional and depositional volumes of small gullies that incise these LDM deposits, we show that it must contain between 46\% and 95\% ice by volume. Extrapolating to a global scale, these deposits account for {\textasciitilde}104 km3 of near-surface ice, doubling previous LDM volume estimates [Kreslavsky and Head, 2002]. Thick LDM deposits can be emplaced during the many orbital variation-driven climate excursions [Jakosky and Carr, 1985] that occurred during the Amazonian. We suggest LDM deposits are similar to ice-sheets composed of massive ice with a surface lag.