在中海山脊的断层模式
W Roger Buck1, Luc L Lavier, Alexei N B Poliakov
1Lamont-Doherty Earth Observatory of Columbia University, Palisades, New York 10964, USA. buck@ldeo.columbia.edu
Nature
|April 9, 2005
概括
海洋地断层是最常见的构造特征,在板块扩散中心形成. 两个不同的机制,板不曲和板拉伸与岩石堤入侵,解释他们的各种大小和方向.
科学领域:
- 地质地质地质地质地质地
- 构造学 构造学 构造学 构造学
- 海洋学 海洋学 海洋学
背景情况:
- 巨大的山丘界断层是地球海洋地上最常见的构造特征.
- 它们在板块扩散中心的形成是在板块构造革命期间建立的.
- 最近的数据显示,断层尺寸和方向的范围广泛.
研究的目的:
- 为了阐明负责在中海山脊断层形成的独特机制.
- 为了使观察到的断层特征与板块构造学数值模型相协调.
主要方法:
- 板块分离,堤入侵和断层的数值建模.
- 在快速扩散的中心通过板块不曲的断层形成的分析.
- 通过板块拉伸和岩堤侵入,检查缓慢扩散的山脊上的断层形成.
主要成果:
- 板不曲成功地模拟了断层俯冲方向和快速扩散中心的偏移.
- 板块延伸与可变的岩堤入侵解释了缓慢扩散的山脊上的多种断层偏移.
- 非常大的补偿正常断层需要显著的堤入侵 (大约50%的板块分离).
结论:
- 两种主要机制控制了中洋山脊的断层形成:板块不曲和板块拉伸.
- 岩堤的侵入在适应板块分离方面发挥着至关重要的作用,特别是在形成大偏移断层时.
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