概括
南加州在1977年至1982年间经历了显著的地变形. 重力,海拔和应变数据显示了相关的变化,表明了真正的地质变化.
科学领域:
- 地质物理学 地质物理学
- 地质测量是指地质测量.
- 构造学 构造学 构造学 构造学
背景情况:
- 南加州是一个地震活跃的地区,容易发生地变形.
- 了解地运动对于地震危险评估至关重要.
研究的目的:
- 为了研究加利福尼亚州南部的重力,高度和应变的相关变化.
- 评估1977年至1982年的地变形测量的有效性.
主要方法:
- 精确的重力测量每半年进行一次.
- 沿着长基线进行重复的海拔调查.
- 激光测距调查以测量面积应变.
主要成果:
- 在6个月内观察到的重力变化高达25微加尔.
- 在40-100公里的基线上,每年的海拔变化达到100毫米.
- 在加利福尼亚州南部检测到1至2百万分之一的区域变异.
结论:
- 从多种地理测量技术的相关测量表明真实的地变形.
- 这些发现提供了在研究期间在加利福尼亚州南部发生重大地质活动的证据.
- 尽管存在准确性问题,但系统之间的协议支持观察到的变化的现实.
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