木星卫星Io上的高温酸盐火山活动
A S McEwen1, L Keszthelyi, J R Spencer
1Lunar and Planetary Lab, University of Arizona, Tucson, AZ 85711, USA. mcewen@lpl.arizona.edu
Science (New York, N.Y.)
|July 4, 1998
概括
我相信你,我相信你,我相信你
科学领域:
- 行星科学 行星科学
- 火山学 火山学是一门学科.
- 地质化学 地质化学
背景情况:
- 木星的火山卫星Io表现出极端的火山活动.
- 以前的观测表明喷发温度很高,但精确的测量是有限的.
研究的目的:
- 为了确定Io上的岩喷发的温度.
- 为了确定Io的火山岩的组成.
主要方法:
- 利用了来自利略航天器的红外光谱数据.
- 分析了Io岛上至少12个不同的火山口的热辐射.
- 应用热力学模型来估计岩温度.
主要成果:
- 观测到的岩温度超过1700凯尔文,有些可能达到2000凯尔文.
- 在Io岛上发现了至少12个活跃的火山口.
- 在岩流中暂时确定了富含的orthopyroxene,这表明了超的组成.
结论:
- 伊奥的火山岩比地球的岩岩要热得多.
- 这种高温支持了Io上超级岩组成的假设.
- 利略的观测为Io的极端火山活动提供了前所未有的洞察力.
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