Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5487372 | Icarus | 2017 | 14 Pages |
Abstract
Modern N2 ice glaciers flow from highlands to the east of the 750Â ÃÂ 1400Â km2 lowland of Sputnik Planum [SP] and merge with the ices of similar composition on SP. We explore the possibility that glaciation may be fed by N2 sublimation from SP followed by redeposition on the highlands. The uplands to the northeast, north, and west of SP have been erosionally sculpted into a variety of dissected terrains that feature linear depressions (valleys), locally in dendritic networks. We interpret these dissected terrains to have been carved by N2 glaciers formerly covering the uplands. Depositional glacial landforms (moraines, eskers, outwash) have not been identified, however. N2 glaciation would have a different erosional manifestation because the substrate (porous water ice and CH4-rich mantles) probably has lower density than N2, and also because of the lack of freeze-thaw weathering. If sufficiently thick (1-4Â km), N2 glaciers might have experienced basal melting. Past flow of N2 glaciers from the highlands into SP may have detached and transported the prominent mountainous water ice mountains along the western border of SP.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Space and Planetary Science
Authors
Alan D. Howard, Jeffrey M. Moore, Orkan M. Umurhan, Oliver L. White, Robert S. Anderson, William B. McKinnon, John R. Spencer, Paul M. Schenk, Ross A. Beyer, S. Alan Stern, Kimberly Ennico, Cathy B. Olkin, Harold A. Weaver, Leslie A. Young,