Crater erasure
Crater erasure in planetology is the process of leveling impact craters on atmospheric planetary bodies in the absence of volcanic geological processes .
The surface of atmospheric planetary bodies is shaped in the absence of geological erosion by impact craters caused by the impact of comets , asteroids, and micrometeoroids . Despite the absence of erosion, the craters are leveled by the following processes:
- Cookie cutting describes the destruction of impact craters by the formation of new overlying craters
- Ejecta blanketing (= covering with ejection) is the covering of the craters by regolith , which is whirled up when distant new craters are formed
- Sandblasting (= sandblasting) describes the effect of impacts of micrometeoroids that the crater wall planarizing
- Landslide on the crater rim triggered by seismic shaking due to meteoroid impacts. This process is particularly effective in the case of asteroids, whose low surface acceleration favors a rearrangement of surface material
The extinction of impact craters limits the accuracy of the age of the planetary surface derived from the crater statistics (more precisely from the diameter frequency distribution). The age calculated from the statistics is only a lower limit since a balance was reached between the formation of new and the leveling of old craters.
literature
- Masatoshi Hirabayashi, David A. Minton, Caleb I. Fassett: An analytical model of crater count equilibrium . In: Astrophysics. Solar and Stellar Astrophysics . 2017, arxiv : 1701.00471v1 .
- Tomoya M. Yamada, Kousuke Ando, Tomokatsu Morota, Hiroaki Katsuragi: Timescale of asteroid resurfacing by regolith convection resulting from the impact-induced global seismic shaking . In: Astrophysics. Solar and Stellar Astrophysics . 2015, arxiv : 1508.06485v2 .
- Raphael F. Garcia, Naomi Murdoch, David Mimoun: Micro-meteoroid seismic uplift and regolith concentration on kilometric scale asteroids . In: Astrophysics. Solar and Stellar Astrophysics . 2015, arxiv : 1503.01893v1 .
Web links
Individual evidence
- ↑ Definition and illustration , accessed on September 30, 2017.