Global S&T Development Trend Analysis Platform of Resources and Environment
DOI | 10.1038/NGEO2937 |
A post-accretionary lull in large impacts on early Mars | |
Bottke, William F.1,3; Andrews-Hanna, Jeffery C.3 | |
2017-05-01 | |
发表期刊 | NATURE GEOSCIENCE |
ISSN | 1752-0894 |
EISSN | 1752-0908 |
出版年 | 2017 |
卷号 | 10期号:5 |
文章类型 | Article |
语种 | 英语 |
国家 | USA |
英文摘要 | The early impact bombardment of Mars has been linked to the bombardment history of the inner Solar System as a whole. However, the timing and number of basin-forming impacts on Mars are poorly constrained. The Borealis basin-thought to be the largest and oldest known Martian impact basin-forms the crustal dichotomy between the northern lowlands and southern highlands. Four unambiguous large basins post-dating Borealis have been identified, but as many as 32 additional basins larger than 1,000 km in diameter have been proposed. Here we use gravity and topography analyses to show that the crustal dichotomy boundary was excavated by only one later impact basin (Isidis), which probabilistically indicates that fewer than 12 large basins across the globe could post-date the boundary and pre-date the established younger basins. Moreover, the relatively pristine topography and crustal thickness at the dichotomy boundary indicates that younger basins should be similarly well preserved. This suggests that the post-Borealis large basin population is limited to only the four known younger basins, with estimated ages between 3.8 and 4.1Gyr ago (Ga). We present geochemical arguments that Borealis dates to near 4.5 Ga. Combined with Monte Carlo simulations, we argue that, instead of a gradually declining impactor flux, a lull in large basin-forming impacts occurred between about 4.1 and 4.4 Ga on Mars, separating the endgame of accretion from a putative late heavy bombardment similar to that proposed for the Moon and asteroid belt. |
领域 | 地球科学 ; 气候变化 |
收录类别 | SCI-E |
WOS记录号 | WOS:000400407000010 |
WOS关键词 | MARTIAN HEMISPHERIC DICHOTOMY ; HEAVY BOMBARDMENT ; CONSTRAINTS ; TOPOGRAPHY ; CHRONOLOGY ; THICKNESS ; ORIGIN ; CRUST ; METEORITES ; EVOLUTION |
WOS类目 | Geosciences, Multidisciplinary |
WOS研究方向 | Geology |
引用统计 | |
文献类型 | 期刊论文 |
条目标识符 | http://119.78.100.173/C666/handle/2XK7JSWQ/35007 |
专题 | 地球科学 气候变化 |
作者单位 | 1.Southwest Res Inst, Boulder, CO 80302 USA; 2.NASA, SSERVI Inst Sci Explorat Targets ISET, Boulder, CO 80302 USA; 3.Univ Arizona, Lunar & Planetary Lab, Tucson, AZ 85721 USA |
推荐引用方式 GB/T 7714 | Bottke, William F.,Andrews-Hanna, Jeffery C.. A post-accretionary lull in large impacts on early Mars[J]. NATURE GEOSCIENCE,2017,10(5). |
APA | Bottke, William F.,&Andrews-Hanna, Jeffery C..(2017).A post-accretionary lull in large impacts on early Mars.NATURE GEOSCIENCE,10(5). |
MLA | Bottke, William F.,et al."A post-accretionary lull in large impacts on early Mars".NATURE GEOSCIENCE 10.5(2017). |
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