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Lunar impact basins: stratigraphy, sequence and ages from superposed impact crater populations measured from lunar orbiter laser altimeter (lola) data
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Kadish, S. J. Mazarico, E. Fassett, C. I. Head, J. W. Neumann, G. A. Zuber, M. T. Smith, D. E. |
| Copyright Year | 2012 |
| Description | Impact basin formation is a fundamental process in the evolution of the Moon and records the history of impactors in the early solar system. In order to assess the stratigraphy, sequence, and ages of impact basins and the impactor population as a function of time, we have used topography from the Lunar Orbiter Laser Altimeter (LOLA) on the Lunar Reconnaissance Orbiter (LRO) to measure the superposed impact crater size-frequency distributions for 30 lunar basins (D ⥠300 km). These data generally support the widely used Wilhelms sequence of lunar basins, although we find significantly higher densities of superposed craters on many lunar basins than derived by Wilhelms (50% higher densities). Our data also provide new insight into the timing of the transition between distinct crater populations characteristic of ancient and young lunar terrains. The transition from a lunar impact flux dominated by Population 1 to Population 2 occurred before the mid-Nectarian. This is before the end of the period of rapid cratering, and potentially before the end of the hypothesized Late Heavy Bombardment. LOLA-derived crater densities also suggest that many Pre-Nectarian basins, such as South Pole-Aitken, have been cratered to saturation equilibrium. Finally, both crater counts and stratigraphic observations based on LOLA data are applicable to specific basin stratigraphic problems of interest; for example, using these data, we suggest that Serenitatis is older than Nectaris, and Humboldtianum is younger than Crisium. Sample return missions to specific basins can anchor these measurements to a Pre-Imbrian absolute chronology. |
| File Size | 1421542 |
| Page Count | 13 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20130014881 |
| Archival Resource Key | ark:/13960/t51g5pq1c |
| Language | English |
| Publisher Date | 2012-02-02 |
| Access Restriction | Open |
| Subject Keyword | Time Dependence Lunar Evolution Structural Basins Topography Lunar Craters Laser Altimeters Stratigraphy Sample Return Missions Chronology Solar System Lunar Orbiter Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
