一个超缓慢扩散的山脊的火山进化
H H Stubseid1, A Bjerga2, H Haflidason2
1Center for Deep Sea Research and Department of Earth Science, University of Bergen, Allégaten 41, N-5007, Bergen, Norway. havard.stubseid@uib.no.
Nature communications
|July 12, 2023
概括
海洋地在超缓慢扩散的山脊上显示出典型区域之外的年轻火山活动. 这项研究显示,近一半的裂谷地板在过去的25,000年里因火山活动而再生.
科学领域:
- 地质物理学 地质物理学
- 海洋地质 海洋地质学
- 板块构造学是一种板块构造学.
背景情况:
- 中洋山脊占海洋地形成的近30%,特别是在超低传播速度 (<20毫米/年) 的情况下.
- 海底扩散模式表明,海洋地在狭窄的轴心区域形成,并远离裂谷.
- 火山爆发的定量年龄数据很少,这阻碍了地质模型的超慢传播地的进化.
研究的目的:
- 为了构建地质模型的超慢传播地的进化.
- 为了确定莫恩斯山脊海底的年龄.
- 为了揭示轴心火山脊外的火山活动模式.
主要方法:
- 利用约4000公里的下底分析仪数据来绘制沉积物厚度的地图.
- 嵌入式碳-14 (C) 从沉积物核心中老化.
- 在裂谷内部生成了上层岩流的年龄地图.
主要成果:
- 揭示了在轴性火山脊外发生的年轻火山活动的系统模式.
- 证明了近一半的裂谷地板在过去25,000年内被火山复兴.
- 提供了上层岩流的定量年龄图.
结论:
- 在超慢扩散的山脊上,火山活动在裂谷内比以前所认为的更为广泛.
- 这些发现挑战了海底扩散在这些缓慢扩散的环境中的传统模型.
- 这项研究为了解超慢传播的海洋地的动态演变提供了关键数据.
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