埃尔市长-库卡哈地震的近场变形通过差异激光雷达显示
Michael E Oskin1, J Ramon Arrowsmith, Alejandro Hinojosa Corona
1Department of Geology, University of California, Davis, 1 Shields Avenue, Davis, CA 95618, USA. meoskin@ucdavis.edu
Science (New York, N.Y.)
|February 11, 2012
概括
大规模的大陆地震可能会在多个断层上造成复杂的断裂. 2010年埃尔迈奥-库卡哈地震的高分辨率光探测和距离 (LIDAR) 调查揭示了以前未知的盲断层和显著的地面变形.
科学领域:
- 地质物理学 地质物理学
- 构造学 构造学 构造学 构造学
- 遥感 遥感 遥感 遥感
背景情况:
- 大规模的大陆地震 (时刻大小≥7) 经常表现出复杂的多断层断裂.
- 这些破裂通常与分布式变形区域有关,其性质仍然不完全理解.
研究的目的:
- 通过使用高分辨率的空中光探测和距离测量 (LIDAR) 数据,调查与2010年埃尔迈奥-库卡哈地震相关的复杂表面破裂模式和变形.
- 识别以前未经记录的断层,并描述断层区域的应变分布.
主要方法:
- 获取高分辨率 (≥9个返回每平方米) 的空中LIDAR地形数据地震后.
- 将地震后的LIDAR数据与地震前的低分辨率 (5米像素) LIDAR数据进行比较,以创建差异性的LIDAR调查.
- 分析差异性高度变化以量化表面变形和识别断层结构.
主要成果:
- 2010年埃尔市长-库卡哈地震在墨西哥最北部的巴哈加利福尼亚州产生了120公里长的多断层断裂.
- 差异性激光雷达调查显示,科罗拉多河三角洲沉积物中的许多表面破裂和以前未经记录的盲断层.
- 观察到千米级的曲应变,达到大约10^3微应变,以应对不连续断层上的滑动.
结论:
- 高分辨率的LIDAR有效地捕获大规模大陆地震的详细地表破裂特征,即使在植被稀疏的地区.
- 该研究确定了以前未被识别的盲断层和显著的分布变形,突出了地震破裂过程的复杂性.
- 这些发现有助于更好地了解大地震如何变形地球表面以及断层复杂性的作用.
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