在欧罗巴的冰中,有固态对流的地质证据
R T Pappalardo1, J W Head, R Greeley
1Department of Geological Sciences, Brown University, Providence, Rhode Island 02912-1846, USA. robert_pappalardo@brown.edu
Nature
|February 5, 1998
概括
欧洲欧洲欧洲欧洲欧洲欧洲
科学领域:
- 行星科学 行星科学
- 地质物理学 地质物理学
- 天体生物学 天体生物学
背景情况:
- 木星的卫星欧罗巴有一个地质活跃的,富含冰的表面.
- 来自潮力量的内部热量可能会维持地下液态水层.
- 热量损失和重新表面的机制仍然不清楚.
研究的目的:
- 研究塑造欧洲表面的地质过程.
- 解释由利略航天器观测到的表面特征.
- 评估地下液态水海洋的证据.
主要方法:
- 分析高分辨率的利略航天器对欧洲的图像.
- 表面特征的形态和地质解释 (坑,圆顶,斑点).
- 在欧罗巴的冰中模拟热诱导的固态对流.
主要成果:
- 确定了不同的表面特征,被解释为尿布 (上升的温暖冰块).
- 这些特征的形成是由冰中的固态对流解释的.
- 结果与可能的地下液态水层或海洋相一致.
结论:
- 由固态对流驱动的皮层上升是欧罗巴上一个合理的复苏机制.
- 这些发现支持了地下液态水海洋的假设.
- 为了获得欧洲海洋的确证据,还需要进一步的观测.
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