DOI: 10.1029/2017JE005446
Scopus记录号: 2-s2.0-85049829641
论文题名: Lunar Orientale Impact Basin Secondary Craters: Spatial Distribution, Size-Frequency Distribution, and Estimation of Fragment Size
作者: Guo D. ; Liu J. ; Head J.W. ; III ; Kreslavsky M.A.
刊名: Journal of Geophysical Research: Planets
ISSN: 21699097
出版年: 2018
卷: 123, 期: 6 起始页码: 1344
结束页码: 1367
语种: 英语
英文关键词: oblique impact
; Orientale basin
; scaling law
; secondary crater
; size-frequency distribution
; South Pole-Aitken basin
Scopus关键词: crater
; ejecta
; impact structure
; lunar crust
; regolith
; satellite sensor
; size distribution
; spatial distribution
英文摘要: Secondary impact craters, features created by projectiles ejected from a primary impact, contain important information about the primary cratering event and the nature and distribution of its ejecta. The Orientale impact basin (D ~ 930 km) is the youngest and the least degraded large impact basin on the Moon and has the most recognizable secondary impact craters. We identified and mapped 2,728 secondary craters in the investigated area of ~1.66 × 107 km2, covering an area from the rim of Orientale to six radii. Secondary crater diameters range from ~2 to 27 km, and the median diameter decreases as distance increases. Secondary craters are concentrated predominantly in the northwest and southwest. The ejecta deposit pattern inferred from secondary crater distribution suggests that the Orientale basin was formed by an oblique impact in which the downrange direction was 240°–265° in azimuth, and the incidence angle was steeper than 20°. The cumulative size-frequency distribution of mapped secondary craters steepens as diameter increases and is very well approximated with a Weibull distribution with an exponent 1.32. A widely used crater scaling relationship predicts that the fragments that produced the secondary craters were predominantly in ~0.5–2-km diameter range over the investigated area; the diameter of the largest fragment, however, decreases with increasing distance from Orientale. On the basis of the diameter of the largest secondary crater of Orientale, and other craters and basins, the largest secondary crater of the South Pole-Aitken basin is estimated to be ~40 km in diameter. We explore the implications of these findings for the evolution of the megaregolith and future sample return missions. ©2018. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/113794
Appears in Collections: 气候减缓与适应
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作者单位: Center for Lunar and Planetary Sciences, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, China; University of Chinese Academy of Sciences, Beijing, China; Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI, United States; Earth and Planetary Sciences, University of California, Santa Cruz, CA, United States
Recommended Citation:
Guo D.,Liu J.,Head J.W.,et al. Lunar Orientale Impact Basin Secondary Craters: Spatial Distribution, Size-Frequency Distribution, and Estimation of Fragment Size[J]. Journal of Geophysical Research: Planets,2018-01-01,123(6)