火星海洋因海岸线变形而形成的时间
Robert I Citron1,2, Michael Manga1,2, Douglas J Hemingway1,2
1Department of Earth and Planetary Science, University of California, Berkeley, Berkeley, California, USA.
Nature
|March 21, 2018
概括
古老的火星海洋可能存在,海岸线证明了这一点. 新的研究表明,这些海岸线是在塔西斯火山活动期间形成的,而不是之后,解决了地质不一致性,并支持了早期的火星水.
科学领域:
- 星球科学
- 地质学
- 天体生物学
背景情况:
- 证据表明古老的火星海洋, 北方平原的海岸线作为关键指标.
- 这些海岸线偏离了等电平面,挑战了海洋假设.
- 之前的解释涉及Tharsis形成后的真正极地流浪与Tharsis的赤道起源不一致.
研究的目的:
- 为了解释古代火星海岸线的偏离,
- 为了使海岸线的地形与火星的地质模型相协调.
- 确定火星海洋形成的时间与塔西斯火山相比.
主要方法:
- 由Tharsis的位置引起的地变形的地球物理建模.
- 分析海岸线的地形变化.
- 模型结果与观察数据的比较.
主要成果:
- 海岸线的地形变化是由tharsis位置的变形解释的.
- 沿海线形成之前和期间, 而不是之后, 塔西斯的安置.
- 这解决了非等效海岸线的地质不一致性.
结论:
- 火星的海洋在这个星球的早期形成, 与山谷网络形成相吻合.
- 海洋进化与塔尔西斯火山的开始和衰退密切相关.
- 这对火星早期的地质,水文和气候有重大影响.
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