北埃及的地速度结构使用环境噪声断层扫描
Hany A A Adam1,2, Takumi Hayashida2, M Sami Soliman1
1Seismology Department, National Research Institute of Astronomy and Geophysics (NRIAG), Cairo, Egypt.
Scientific reports
|November 27, 2025
概括
这项研究使用环境噪声断层扫描揭示了埃及北部明显的地速度变化. 在西部沙漠中发现低速度,而在东部沙漠和西奈地区出现更高速度,计算的Moho深度在31-42公里之间.
科学领域:
- 地质物理学 地质物理学
- 地震学 地震学
- 构造学 构造学 构造学 构造学
背景情况:
- 北埃及是东地中海地震活跃地区的一部分,具有复杂的构造环境.
- 此前对该地区地结构的研究是有限的.
研究的目的:
- 通过使用环境噪声断层扫描 (ANT) 调查埃及北部地结构.
- 为了确定整个研究区域的地震波速度和Moho深度的变化.
主要方法:
- 利用来自32个宽带地震站 (埃及国家地震网络和南欧地区站) 一年的连续数据.
- 应用环境噪声断层扫描 (ANT) 通过根据信号与噪声比和季节性变化选择约300个分散曲线.
- 逆转选定的分散曲线以生成组速度图 (5-25秒) 并计算9个地点的Moho深度.
主要成果:
- 在埃及北部的群体速度中发现了显著的横向变化.
- 在北西部沙漠的地中观察到低地震速度.
- 在东北部沙漠和西奈半岛检测到更高的速度.
- 估计Moho深度从31公里 (地中海海岸附近) 到42公里 (西沙漠).
- 在西奈半岛下方的Moho深度计算为33-35公里.
- 确定了康拉德不连续性深度在10至16公里之间.
结论:
- 该研究提供了使用ANT.使用埃及北部的第一个详细的地结构地图.
- 结果突出了地厚度和地震速度的显著变化,与区域构造特征相关.
- 这些发现有助于更好地了解东地中海地区复杂的地力学.
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