TES and THEMIS Observations of Isolated Basalt Regions in the Northern Hemisphere of Mars

Details TES and THEMIS Observations of Isolated Basalt Regions in the Northern Hemisphere of Mars TES and THEMIS Observations of Isolated Basalt Regions in the Northern Hemisphere of Mars

May 2002

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2002agusm.p31a..06r&link_type=abstract

American Geophysical Union, Spring Meeting 2002, abstract #P31A-06

Physics

5410 Composition, 5464 Remote Sensing, 5480 Volcanism (8450)

Scientific paper

Using atmospherically-corrected TES emissivity spectra, [1] and [2] identified two major surface types on Mars: basalt and andesite. From low-resolution (1 ppd) global maps of the distributions of the two surface types, [1] concluded that the basalt is restricted to the cratered terrain, and andesite is concentrated primarily in the northern lowlands, but also has significant concentrations throughout the cratered highlands. On the 1 ppd maps, it is difficult to determine a precise boundary between the two compositions, because of large dusty areas that obscure the composition of underlying bedrock. In this work, high-resolution (32 ppd) TES observations are used to define the northern extent of the basalt surface type, by resolving small, isolated regions of basalt within the dusty areas and northern lowlands. Twenty-four isolated basalt regions are identified in this study; all but four of these are located within the cratered terrain morphology. The four outlier regions within the lowlands are found in Cerberus, Milankovic Crater, Pettit Crater, and Erebus Montes. Possible origins for the basalt in the outlier regions include: local basalt flows; basalt derived from nearby volcanic provinces; basalt eroded from adjacent knobby terrain; or, an impactor "punched through" an andesitic resurfacing layer to expose basalt from underneath. Thus, the basalt in all of these regions can be related to the cratered terrain morphology in the highlands, either from erosion of the knobby terrain (previously interpreted as cratered highland remnants) or by impact-excavation. The locations of the isolated basalt regions imply that the basaltic surface composition is closely associated with the ancient cratered terrain morphology, and is old relative to the andesitic resurfacing materials in the lowlands. The outlier regions in the lowlands suggest a stratigraphic relationship between the basalt and andesite, such that a heavily cratered, basaltic crust may continue north into the lowlands, underneath a younger, andesitic resurfacing layer. The regions in this study are currently being targeted with the 2001 Mars Odyssey THEMIS instrument. The higher spatial resolution of THEMIS (100 m/pixel), relative to TES (3 km/pixel) may show the spatial variability of basalt in these regions, as well as resolve surface features that correspond with the detected basalt signature. Results from THEMIS observations of these regions will also be presented. [1] Bandfield et al., Science, 287, 1626-30, 2000. [2] Christensen et al., JGR, 105, 9609-21, 2000.

Affiliated with

Also associated with

No associations

Rating

TES and THEMIS Observations of Isolated Basalt Regions in the Northern Hemisphere of 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 TES and THEMIS Observations of Isolated Basalt Regions in the Northern Hemisphere of Mars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and TES and THEMIS Observations of Isolated Basalt Regions in the Northern Hemisphere of Mars will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1721699