Smith D E, Sjogren W L, Tyler G L, Balmino G, Lemoine F G, Konopliv A S
Laboratory for Terrestrial Physics, National Aeronautics and Space Administration (NASA) Goddard Space Flight Center, Greenbelt, MD 20771, USA.
Science. 1999 Oct 1;286(5437):94-7. doi: 10.1126/science.286.5437.94.
Observations of the gravity field of Mars reveal a planet that has responded differently in its northern and southern hemispheres to major impacts and volcanic processes. The rough, elevated southern hemisphere has a relatively featureless gravitational signature indicating a state of near-isostatic compensation, whereas the smooth, low northern plains display a wider range of gravitational anomalies that indicates a thinner but stronger surface layer than in the south. The northern hemisphere shows evidence for buried impact basins, although none large enough to explain the hemispheric elevation difference. The gravitational potential signature of Tharsis is approximately axisymmetric and contains the Tharsis Montes but not the Olympus Mons or Alba Patera volcanoes. The gravity signature of Valles Marineris extends into Chryse and provides an estimate of material removed by early fluvial activity.
对火星引力场的观测显示，这颗行星的南北半球对重大撞击和火山活动的反应有所不同。崎岖高耸的南半球具有相对无特征的引力特征，表明处于近均衡补偿状态，而平坦低洼的北半球平原则显示出更广泛的引力异常，这表明其表层比南半球更薄但更强。北半球有证据表明存在埋藏的撞击盆地，尽管没有一个大到足以解释半球高度差异。塔尔西斯的引力势特征大致呈轴对称，包含塔尔西斯山脉，但不包括奥林匹斯山或阿尔巴帕特拉火山。水手号峡谷的引力特征延伸到克里斯平原，并提供了早期河流活动所移除物质的估计值。
