Computer Science – Sound
Scientific paper
Dec 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006natur.444..905w&link_type=abstract
Nature, Volume 444, Issue 7121, pp. 905-908 (2006).
Computer Science
Sound
20
Scientific paper
A hemispheric dichotomy on Mars is marked by the sharp contrast between the sparsely cratered northern lowland plains and the heavily cratered southern highlands. Mechanisms proposed to remove ancient crust or form younger lowland crust include one or more giant impacts, subcrustal transport by mantle convection, the generation of thinner crust by plate tectonics, and mantle overturn following solidification of an early magma ocean. The age of the northern lowland crust is a significant constraint on these models. The Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument on the European Space Agency's Mars Express spacecraft is providing new constraints on the martian subsurface. Here we show evidence of buried impact basins ranging in diameter from about 130km to 470km found over ~14 per cent of the northern lowlands. The number of detected buried basins >200km in diameter indicates that the lowland crust is ancient, dating back to the Early Noachian epoch. This crater density is a lower limit because of the likelihood that not all buried basins in the area surveyed by MARSIS have been detected. An Early Noachian age for the lowland crust has been previously suggested on the basis of a large number of quasi-circular topographic depressions interpreted to be evidence of buried basins. Only a few of these depressions in the area surveyed by MARSIS, however, correlate with the detected subsurface echoes. On the basis of the MARSIS data, we conclude that the northern lowland crust is at least as old as the oldest exposed highland crust. This suggests that the crustal dichotomy formed early in the geologic evolution of Mars.
Clifford Stephen M.
Farrell William M.
Ivanov Anton B.
Leuschen Carl J.
Phillips Roger J.
No associations
LandOfFree
MARSIS radar sounder evidence of buried basins in the northern lowlands 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 MARSIS radar sounder evidence of buried basins in the northern lowlands of Mars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and MARSIS radar sounder evidence of buried basins in the northern lowlands of Mars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1550144