南中国海下面的地幔流通过地震异质性揭示了地幔流
Fansheng Kong1,2,3, Rui Gao2,4, Stephen S Gao3
1Key Laboratory of Submarine Geosciences, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou310012, China.
National science review
|September 6, 2023
概括
南中国海的地幔流有主导的北北北东方方向,由印度-欧亚碰撞驱动. 这种流动并没有从东亚的陆地延伸到中部海洋盆地.
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
- 地震学 地震学
背景情况:
- 星球上的塑料流影响了石化层和地震和火山等地质危险.
- 描述地幔流动的方向和范围具有挑战性,特别是在海洋地区,因为数据稀少.
研究的目的:
- 为了确定南中国海中部的地幔流场.
- 调查印度-欧亚碰撞对该地区地幔动态的影响.
主要方法:
- 在2019年中期至2020年中期在南中国海部署一个海底地震计 (OBS) 阵列.
- 对地震剪波分裂的分析,以推断地幔流动方向.
主要成果:
- 确定了南中国海中部一个占主导地位的NNW-SSE地幔流动方向.
- 由于印度-欧亚洲碰撞,将这种流量归因于来自西藏高原的地幔挤出.
- 发现,南中国和印度支那的东西导流场并不延伸到中部的南中国海.
结论:
- 南中国海中部的地幔流场主要受到西藏高原动态的影响.
- 海洋地幔流动模式与在邻近的大陆地区观察到的不同.
- 提供了关键数据,以了解海洋构造环境中的地质危险潜力.
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