在东南极和西南极之间发生的纪运动
1Scripps Institution of Oceanography, La Jolla, California 92093-0215, USA. scande@ucsd.edu
Nature
|March 21, 2000
概括
新的研究揭示了东南极和西南极之间的距离约为180公里,在欧纪和奥利古纪. 这种西南极裂系统的发展解释了关键的构造事件,并完善了全球板块运动模型.
科学领域:
- 地质物理学 地质物理学
- 板块构造学是一种板块构造学.
- 古地质学 古地质学
背景情况:
- 西南极裂系统是一个主要的活跃大陆裂,由中生代和中生代在东南极和西南极之间的延伸形成.
- 以前对裂系统发展的理解受到了海底扩散约束的缺乏,特别是磁异常和断裂区域数据的限制.
研究的目的:
- 为了确定负责西南极裂系统形成的板块运动的时间和大小.
- 改进包括澳大利亚,南极和太平洋板块在内的板块电路的重建.
主要方法:
- 在塔斯曼海南部和罗斯海北部收集的磁力数据,重力数据和海域浴度分析.
- 基于收集的地质物理数据,计算了东南极和西南极的中古时代旋转参数.
主要成果:
- 证据表明,东南极与西南极之间在西罗斯海湾区间的距离大约为180公里,发生在世和奥利古世时期.
- 确立了东南极和西南极的中古时代旋转参数.
- 解决了新西兰地区早期三级重建中的差异,并澄清了南极变形对全球板块电路的贡献.
结论:
- 计算的东西南极运动为罗斯海海域中重要的纪事件提供了构造学框架,包括跨南极山脉的升起和广泛的奥利戈纪沉积物沉积.
- 结合这种运动可以完善板块重建,并解决关于太平洋板块相互作用的长期争议.
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