在大陆裂区域的岩补偿地稀释
1Department of Geography and Geology, University of Copenhagen, Oester Voldgade 10, DK-1350 Copenhagen K, Denmark. thybo@geo.ku.dk
Nature
|February 13, 2009
概括
贝加尔河裂区显示出一个独特的下层地高速区域,挑战传统的大陆裂区模型. 这表明岩入侵在裂发展中起着关键作用.
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
- 地球科学 地球科学 地球科学
背景情况:
- 大陆裂区是由石质层延伸形成的构造性低谷.
- 裂变可能导致海洋地形成或沉积盆地.
- 传统模型预测莫霍的浅层和减少地幔地震速度.
研究的目的:
- 为了研究贝加尔河裂区的地和地幔特征.
- 测试传统的裂模型与新的地震数据对比.
- 了解岩在大陆裂变中的作用.
主要方法:
- 在贝加尔湖南部获得了一个新的地震概况.
- 分析地震数据以确定地和地幔结构.
- 观察到的特征与已建立的裂模型进行比较.
主要成果:
- 贝加尔河裂区表现出表面的地形低谷,但缺乏预期的莫霍浅层.
- 在下层地中确定了一个局部化的,高速的,高度反射的区域.
- 这一区域被解释为一个显著的岩入侵到地的下层.
结论:
- 贝加尔河裂区偏离了传统的裂模型.
- 下层地的岩石入侵补偿了预期的莫霍升起.
- 这突显了以前未被承认的岩在大陆裂过程中的作用.
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