在1981年和1982年在圣海伦斯山进行变形监测
Science (New York, N.Y.)
|September 30, 1983
概括
圣海伦斯山在1981-1982年的喷发之前是圆顶膨胀和地面变形,允许3-19天的喷发预测. 基于有限的外部变形,岩入侵并不大.
科学领域:
- 火山学 火山学是一门学科.
- 地质物理学 地质物理学
- 构造学 构造学 构造学 构造学
背景情况:
- 圣海伦斯山在1981年和1982年经历了重大的喷发.
- 了解爆发前的过程对于危险评估至关重要.
- 岩圆顶膨胀和地面变形是火山活动的关键指标.
研究的目的:
- 分析1981-1982年圣海伦斯火山爆发之前的变形模式.
- 评估岩入侵,圆顶膨胀和地面变形之间的关系.
- 根据观察到的变形速率来评估喷发预测的潜力.
主要方法:
- 监测圣海伦斯山火山口内和周围的地面变形.
- 分析了岩圆顶膨胀和火山口地板的横向移位.
- 变形速率与喷发时间的相关性.
主要成果:
- 在管道上升的粘性岩膨胀了岩圆顶,导致横向的地面移位和推力断裂.
- 在火山爆发前几周,变形速度显著加快.
- 根据这些加速变形速率,火山爆发可以提前3到19天预测.
- 局限的外部变形表明,1981-1982年间的岩入侵并不是很大.
结论:
- 爆发前的岩运动和岩圆顶膨胀是圣海伦斯山即将爆发的可靠指标.
- 观察到的变形模式为短期喷发预测提供了有价值的工具.
- 变形的有限程度表明,1981-1982年岩事件的体积相对较小.
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