来自地震数据的证据表明,在西藏南部有一层部分化的地层
1R. Kind and Xiaohui Yuan, GeoForschungsZentrum Potsdam, 14473 Potsdam, Germany. James Ni, Jianxin Wu, C. Reese, T. Hearn, Department of Physics, New Mexico State University, Las Cruces, NM 88003, USA. Wenjin Zhao, Chinese Academy of Geological Sciences, Beijing, China Lianshe Zhao, Institute for Geophysics, University of Texas at Austin, Austin, TX 78759, USA. E. Sandvol, Department of Geological Sciences, Cornell University, Ithaca, NY 14853, USA. J. Nabelek, College of Oceanography, Oregon State University, Corvalis, OR 97331, USA.
Science (New York, N.Y.)
|December 6, 1996
概括
对西藏南部的研究.
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:
- 西藏高原的地结构很复杂.
- 了解它的速度变化是了解地震活动的关键.
研究的目的:
- 为了研究西藏南部下面的地速度结构.
- 识别变化及其对地质过程的影响.
主要方法:
- 来自INDEPTH-II被动源实验的地震数据的分析.
- 接收器的功能逆转.
- 雷利波的相位速度分析.
- 遥震P波形辐射元件建模. 遥震P波形辐射元件建模.
主要成果:
- 在地速度中观察到一个显著的南向北变化.
- 在拉萨南部区块下面发现了一个地中部低速度区域.
- 在Tethyan喜马拉雅山脉下面没有检测到低速度区域.
结论:
- 中层地的低速度区域表明,在中层地中有一部分化的层.
- 这一层存在于北方的雅东-古鲁裂下面,并可能存在于西藏南部的大部分地区.
- 这些发现为该地区正在进行的构造演变提供了关键的见解.
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