|
|
BEACON eSpace at Jet Propulsion Laboratory >
JPL Technical Report Server >
JPL TRS 1992+ >
Please use this identifier to cite or link to this item:
http://hdl.handle.net/2014/40227
|
| Title: | Erosion rates at the Mars Exploration Rover landing sites and long-term climate change on Mars |
| Authors: | Golombek, M. P.
Grant, J. A.
Crumpler, L. S.
Greeley, R.
Arvidson, R. E.
Bell, J. F. III
Weitz, C. M.
Sullivan, R.
Christensen, P. R.
Soderblom, L. A.
Squyres, S. W. |
| Keywords: | erosion
surficial geology
erosion rates
environment
weathering
aqueous
Mars |
| Issue Date: | 8-Dec-2006 |
| Publisher: | American Geophysical Union |
| Citation: | Journal Of Geophysical Research, Vol. 111, E12S10, doi:10.1029/2006JE002754, 2006 |
| Abstract: | Erosion rates derived from the Gusev cratered plains and the erosion of weak sulfates by saltating sand at Meridiani Planum are so slow that they argue that the present dry and desiccating environment has persisted since the Early Hesperian. In contrast, sedimentary rocks at Meridiani formed in the presence of groundwater and occasional surface water, and many Columbia Hills rocks at Gusev underwent aqueous alteration during the Late Noachian, approximately coeval with a wide variety of geomorphic indicators that indicate a wetter and likely warmer environment. Two-toned rocks, elevated ventifacts, and perched and undercut rocks indicate localized deflation of the Gusev plains and deposition of an equivalent amount of sediment into craters to form hollows, suggesting average erosion rates of ~0.03 nm/yr. Erosion of Hesperian craters, modification of Late Amazonian craters, and the concentration of hematite concretions in the soils of Meridiani yield slightly higher average erosion rates of 1–10 nm/yr in the Amazonian. These erosion rates are 2–5 orders of magnitude lower than the slowest continental denudation rates on Earth, indicating that liquid water was not an active erosional agent. Erosion rates for Meridiani just before deposition of the sulfate-rich sediments and other eroded Noachian areas are comparable with slow denudation rates on Earth that are dominated by liquid water. Available data suggest the climate change at the landing sites from wet and likely warm to dry and desiccating occurred sometime between the Late Noachian and the beginning of the Late Hesperian (3.7–3.5 Ga). |
| URI: | http://hdl.handle.net/2014/40227 |
| Appears in Collections: | JPL TRS 1992+
|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.
|
