Physics
Scientific paper
Dec 2001
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2001agufm.p22a0538h&link_type=abstract
American Geophysical Union, Fall Meeting 2001, abstract #P22A-0538
Physics
5415 Erosion And Weathering, 5464 Remote Sensing, 5470 Surface Materials And Properties
Scientific paper
Altimetry and gravity data from Mars Orbiter Laser Altimeter (MOLA) shed new light on the already perplexing province of northwestern Arabia Terra (NWAT) (0-45° N, -25 eastward to 40° E). Traditionally, this region has been considered a part of the ancient highlands that cover the southern part of Mars. However, recent results from Mars Global Surveyor reveal that NWAT has several unique properties, indicating that it may have a history considerably different than the rest of the uplands. One major discrepancy separating NWAT from the rest of the highlands is the paucity of valley networks. Additionally, this region has an average elevation of -1.5 km, roughly 3 km below typical highland terrain. Many craters in NWAT exhibit highly subdued crater rims with shallow crater floors and there is a lack of large (>160 km) visible impact basins relative to the rest of the uplands. Further, NWAT has a crustal thickness far less than most highland terrain and is more similar to the thinner crustal province of the northern plains. Erosion, deposition, and exhumation have all been invoked to explain the surface features of NWAT. It has been argued that fluvial denudation might be responsible for the unique morphology of NWAT. Recent work indicates that a massive Late Noachian erosion event shaped this region of Mars and resulted in peneplanation and removal of valley networks. Alternatively, workers proposed that this region is exposed bedrock of the northern plains that has been uplifted. A thick aeolian mantling deposit has been hypothesized to explain the subdued nature of the craters in northeastern Arabia. It has also been postulated that western Arabia was underwater at some point early in martian history and its appearance is attributed to marine erosion and deposition. While aeolian deposition can explain some features of NWAT, these processes would not result in an unusually low elevation, thinner crust, or lack of large craters. The marine hypothesis requires an ocean greater than 4 km deep and covering the entire northern plains to submerge western Arabia and this seems unlikely based on analysis of images and MOLA data. We have recently completed preliminary mapping and crater size-frequency distributions of Arabia Terra using Viking, Mars Orbiter Camera (MOC), and MOLA data. We conclude that fluvial erosion, not deposition, is most consistent with the lack of valley networks, relatively low elevation, thin crust, and the lack of large craters. It remains unclear whether this region is exposed basement of the northern plains that has been uplifted or if it belongs to the highland province and has undergone extraordinary denudation and peneplanation. Nevertheless, water has played a major role in modifying this region.
Hynek Brian Michael
Phillips James R.
No associations
LandOfFree
The Role of Water in the Evolution of the Enigmatic Arabia Terra, Mars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Role of Water in the Evolution of the Enigmatic Arabia Terra, Mars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Role of Water in the Evolution of the Enigmatic Arabia Terra, Mars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1238962