Size‐frequency distribution of different secondary crater populations: 1. Equilibrium caused by secondary impacts
Size‐frequency distribution of different secondary crater populations: 1. Equilibrium caused by secondary impacts
复制标题
不同次生陨石坑群的大小频率分布： 1. 次生撞击造成的平衡
DOI：
10.1002/2016je005139
复制
发表时间：
2016-12
影响因子：
--
通讯作者：
Zhiyong Xiao
中科院分区：
文献类型：
--
作者：
Zhiyong Xiao
撞击坑的堆积是造成无空气行星表面撞击坑数量平衡的主要原因。除了原生陨石坑外，广泛分布的次生陨石坑对局部陨石坑种群平衡的影响研究甚少。本文系统地研究了水星上北斋环形山形成的不同次级环形山群，并与月球上的环形山群进行了比较，以探讨它们对当地环形山群演化的贡献。在短时间内，连续喷出物沉积物上的自次因平衡，平衡的陨石坑人口有一个约为−3的微分尺寸频率分布（SFD）斜率。水星上有大量的背景次生物质，而由原色和潜在的背景次生物质的组合所导致的平衡在月球和水星上遵循相同的模式。形成近场和远场二次辐射的碎片的空间分散是影响相互破坏程度的主要因素，因此也是影响最终陨石坑SFD的主要因素。水星上一些聚集的远距离次级彗星可能是由单个碎片形成的，考虑到它们的大空间分散性和具有相同大小的初级彗星的相同形态，这些次级彗星的SFD翻转可能反映了撞击碎片固有的SFD翻转。近场二次谐波和许多其他远场二次谐波的形态和空间分布与聚集碎片形成一致，二次谐波的相互破坏可能是导致所观察到的SFD翻转的主要原因。不均匀的二次撞击是平衡直径范围内不同陨石坑密度和同时代表面不同风化层厚度的一种可能解释。
Accumulation of impact craters is the major reason causing equilibrium of crater populations on airless planetary surfaces. Besides primary craters, the effect of widespread secondaries on the equilibrium of local crater populations is little studied. Here the different secondary crater populations formed by the Hokusai crater on Mercury are systematically studied, and they are compared with those on the Moon to investigate their contribution to the evolution of local crater populations. Self‐secondaries cause equilibrium on continuous ejecta deposits in a short time, and the equilibrium crater population has a differential size‐frequency distribution (SFD) slope of about −3. Background secondaries are abundant on Mercury, and equilibrium caused by a combination of primaries and potential background secondaries follows the same pattern on the Moon and Mercury. The spatial dispersion of fragments that form both near‐field and distant secondaries is the major factor affecting the degree of mutual destruction and thus the final crater SFD. Some clustered distant secondaries on Mercury are likely formed by individual fragments considering their large spatial dispersion and identical morphology with same‐sized primaries, and the SFD rollovers of these secondaries possibly reflect the inherent SFD rollovers of the impact fragments. Near‐field secondaries and many other distant secondaries have morphology and spatial distribution that are consistent with being formed by clustered fragments, and mutual destruction of secondaries may be the major reason causing the observed SFD rollovers. Heterogeneous secondary impacts are a potential explanation for both different crater densities within the equilibrium diameter range and different regolith thicknesses on coeval surfaces.
登录
查看更多内容
影响因子：
5.2
作者：
M. Kreslavsky;J. Head;G. Neumann;M. Zuber;David E. Smith
通讯作者：
M. Kreslavsky;J. Head;G. Neumann;M. Zuber;David E. Smith
影响因子：
64.8
作者：
Marchi, Simone;Chapman, Clark R.;Strom, Robert G.
通讯作者：
Strom, Robert G.
影响因子：
--
作者：
P. Schultz;D. Gault
通讯作者：
P. Schultz;D. Gault
影响因子：
1.6
作者：
D. Gault
通讯作者：
D. Gault
影响因子：
--
作者：
E. Shoemaker;R. Batson;H. Holt;E. Morris;J. Rennilson;E. Whitaker
通讯作者：
E. Shoemaker;R. Batson;H. Holt;E. Morris;J. Rennilson;E. Whitaker