在超慢扩散的Gakkel山脊高度变化的岩积累
Tao Zhang1, Jiabiao Li2, Xiongwei Niu1
1Key Laboratory of Submarine Geosciences, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China.
Nature
|August 21, 2024
概括
在超慢扩散的山脊上,地的厚度令人惊地变化,而且比预期的更厚. 这可能解释了海洋地积的原因.
科学领域:
- 地质学
- 海洋学
- 构造学
背景情况:
- 在中海山脊的地积形成了海洋石化层.
- 被动地幔上升模型预测薄地的扩散速度<20 mm/年.
研究的目的:
- 拍摄超慢扩散的加克尔山脊的地结构.
- 测试现有的地增殖模型.
主要方法:
- 高分辨率的海底地震仪 (OBS) 实验.
- 对地结构的地震成像.
主要成果:
- 在Gakkel脊轴上观察到的地厚度在3.3至8.9公里之间.
- 在过去的5亿年里,地的厚度在横轴上有所增加.
- 结果与被动地幔上升模型的预测相矛盾.
结论:
- 由融化提取驱动的浮动活性地幔流解释了观察到的地厚度.
- 在较慢的传播速度下,地幔上升具有更大的影响力.
- 地厚度的变化很可能是超慢扩散的山脊所固有的.
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