来自重力回收和内部实验室任务的东方盆地的重力场
Maria T Zuber1, David E Smith2, Gregory A Neumann3
1Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139-4307, USA. zuber@mit.edu.
概括
东方盆地
科学领域:
- 月球地质
- 星球科学
- 撞击坑的形成
背景情况:
- 东方盆地是月球上最年轻,保存最好的大型撞击结构.
- 了解它的形成为我们提供了关于行星演变的洞察力.
研究的目的:
- 使用高分辨率数据调查东方盆地的引力场.
- 确定移位的地物质的体积,并推断短暂的石坑尺寸.
- 分析盆地的环状结构和相关的断层.
主要方法:
- 使用来自重力恢复和内部实验室 (GRAIL) 航天器的数据.
- 在3至5公里水平分辨率下分析引力场数据.
- 绘制了不同的环结构和推断了地下断层.
主要成果:
- 据估计至少 (3.4 ± 0.2) × 10^6公里^3的地物质被挖掘和重新分配.
- 推断过渡性石坑直径在320至460公里之间.
- 解决了三种不同的环形, 并确定了与外环相关的地幔透断层.
结论:
- 东方的地结构对多层盆地形成的模型具有关键约束.
- 格雷尔数据显示了月球撞击盆地的详细地表结构.
- 这项研究提升了我们对月球大规模撞击过程的理解.
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