整个板块的应力放松解释了欧洲古世盆地逆转
Søren B Nielsen1, Erik Thomsen, David L Hansen
1Department of Earth Sciences, University of Aarhus, Finlandsgade 8, DK-8200 Aarhus N, Denmark. sbn@geo.au.dk
Nature
|May 13, 2005
概括
欧洲盆地逆转发生在白纪晚期和中古时代的不同阶段. 这些由不同的构造压力驱动的阶段,揭示了对大陆变形的新见解.
科学领域:
- 构造学 构造学 构造学 构造学
- 结构地质学 结构地质学
- 地力学是什么?地力学是什么?
背景情况:
- 欧洲的古老生态和中生态盆地在白纪晚期和古老生态时期经历了逆转 (缩短).
- 以前的解释将这些反转相归因于来自阿尔卑斯山的压缩力.
研究的目的:
- 区分欧洲白纪晚期和中古时代盆地逆转阶段的结构风格和原因.
- 调查构造应力放松在二次逆转事件中的作用.
主要方法:
- 分析结构风格,包括断裂激活和升起模式,用于不同的反转阶段.
- 应用一个简单的曲模型来解释从初级逆转到二次逆转的过渡.
- 逆转时间与板面应力变化的相关性.
主要成果:
- 纪逆转阶段的特点是狭窄的升起区,反向断层,地缩短,以及不对称的边缘低谷.
- 中古时代阶段表现出更宽的,形的升起,断层运动最小,以及更远端的,浅的边缘低谷.
- 一个曲模型成功地解释了在应力放松后发生的初级,与收相关的反转之后的二次,圆顶反转.
结论:
- 欧洲两个主要的逆转阶段具有不同的结构风格和因果机制.
- 二次逆转是初级逆转放松的可预测后果,由曲过程驱动.
- 整个板块的应力变化,可能与冰岛或非洲-欧洲汇率有关,可能引发了放松逆转的开始.
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