论文标题
对冥王星和夏隆和地形年龄估计的影响陨石坑的影响
Impact Craters on Pluto and Charon and Terrain Age Estimates
论文作者
论文摘要
冥王星的地形展现出各种各样的火山口保留年龄，从没有可识别的陨石坑到遍布着丘陵地形的地区。火山口密度的这种变化与整个冥王星历史上发生的地质活性以及各种重铺样式的风格一致，包括外源性和内源性过程。随着时间的流逝，使用撞击通量和壁壁率的估计值，冥王星的地形沉重的地形似乎相对古老，4 ga或以上。夏隆（Charon）的平滑平原（非正式地称为瓦肯策划者）确实经历了早期的浮雕，但是在Vulcan Planitia上有相对较高的陨石坑的空间密度，并且几乎全部覆盖了其他类型的火山或构造特征。瓦尔坎策划和夏隆上的北部地形都估计是古老的，4 ga或以上。冥王星和夏隆上的陨石坑在其尺寸频率分布（SFD）上也显示出明显的破裂，在该山口分布（SFDS）中，直径大约10-15 km的陨石坑具有较浅的SFD幂律坡度，其斜率比该突破直径大的斜坡。冥王星和夏隆上的这种SFD形状与地球月球上观察到的形状不同，并使Kuiper Belt Impactor SFD的形状与小行星带的形状不同。
Pluto's terrains display a diversity of crater retention ages ranging from areas with no identifiable craters to heavily cratered terrains. This variation in crater densities is consistent with geologic activity occurring throughout Pluto's history and also a variety of resurfacing styles, including both exogenic and endogenic processes. Using estimates of impact flux and cratering rates over time, Pluto's heavily cratered terrains appear to be relatively ancient, 4 Ga or older. Charon's smooth plains, informally named Vulcan Planitia, did experience early resurfacing, but there is a relatively high spatial density of craters on Vulcan Planitia and almost all overprint the other types of volcanic or tectonic features. Both Vulcan Planitia and the northern terrains on Charon are also estimated to be ancient, 4 Ga or older. The craters on Pluto and Charon also show a distinct break in their size-frequency distributions (SFDs), where craters smaller than approximately 10-15 km in diameter have a shallower SFD power-law slope than those larger than this break diameter. This SFD shape on Pluto and Charon is different than what is observed on the Earth's Moon, and gives the Kuiper belt impactor SFD a different shape than that of the asteroid belt.
