Mathematics – Logic
Scientific paper
Dec 2002
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2002agufm.p11b..08r&link_type=abstract
American Geophysical Union, Fall Meeting 2002, abstract #P11B-08
Mathematics
Logic
1821 Floods, 5415 Erosion And Weathering, 5470 Surface Materials And Properties, 6225 Mars
Scientific paper
The THEMIS (Thermal Emission Imaging System) instrument onboard Mars Odyssey is providing both visible and infra-red imaging observations of the martian surface at two scales (18 m/p and 100 m/p respectively). IR observations are being conducted during both day and night. IR imagery records temperature variations which are primarily due to differences in abundances of rocks, indurated materials, sand, and dust on the surface. All of the major outflow channels, valley networks and fossae related channel systems have been imaged thus far in the mission. Outflow Channels: the source regions contain large blocks of chaotic terrain with very coarse (rocky) slopes and talus aprons while the tops of these blocks appear smooth and mantled with finer grained materials (dust). A similar relationship is also seen on the large mesas and buttes near the mouths of several outflow channels (Kasei and Ma'Adim Valles). Channel floor regions located near the mouths of some outflow channels (Ares, Maja, and Kasei Valles) appear to be very rocky. This is most likely the result of deep erosion and stripping of the bedrock by plucking and scouring from high velocity flows. However, Tiu Vallis doesn't show this type of stripping. This may be due to waning stage deposition of fines, and or lower flow velocities and shallower channel incision, which failed to reach the bedrock material. Some streamlined islands (Ares, Athabasca and Mangala Valles) have coarse (rocky) prows, flanks and tails. These may be deposits of coarse bedload (boulders) or erosion and exposure of the rocky material which makes up the islands. Preliminary observations of some islands suggest that these are depositional rather than erosional bedforms. Valley Networks: layers are commonly seen in the upper regions of the walls of these systems. Narrow, incised, discontinuous inner channels with finer grained materials are also seen on the floors of some valley networks (Bahram and Nanedi Valles). Maumee Vallis appears to have pendant shaped features (bars?) near the mouth. Samara Vallis and an unnamed channel have terminal deposits located at their mouths (fans?). Valley network dissection also appears much more prevalent in some regions (Libya Montes) than has ever been seen before. Fossae related channel systems, such as Athabasca, Granicus, Hebrus, and Hrad Valles; and Olympica and Hephaestus Fossae, located near the Tharsis and Elysium volcanic provinces have also been studied. These channels systems are most likely the result of volcano ground ice/water interactions. This makes these systems high priority geologic and astrobiologic targets for future landed missions. Preliminary observations and geologic interpretations of martian fluvial landforms will be presented; early results indicate that Mars has had a very rich and complex fluvial history.
Christensen Per Rex
Malin Michael C.
McEwen Alfred S.
Rice James W. Jr.
No associations
LandOfFree
THEMIS Observations of Fluvial Landforms on 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 THEMIS Observations of Fluvial Landforms on Mars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and THEMIS Observations of Fluvial Landforms on Mars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1891785