概括
全球海洋地每1.10亿年进行一次循环. 大陆的积累速度可能达到每年3.0立方公里,每年可能增加大陆陆面积1.35立方公里.
科学领域:
- 地质地质地质地质地质地
- 地质物理学 地质物理学
- 海洋学 海洋学 海洋学
背景情况:
- 海洋地是不断产生和回收的.
- 沉积过程在物质转移到俯冲区中起着至关重要的作用.
研究的目的:
- 量化性物质形成和沉积堆积的速度.
- 根据俯冲过程估计大陆积聚和净增长率.
主要方法:
- 全球海洋地材料的分析.
- 估计沉积物流入速度 (地质和生物源).
- 模拟物质转移到俯冲区的模型.
主要成果:
- 潜在的性物质形成速度:1.35公里3/年.
- 半地火山沉积物的积累:0.05公里3/年.
- 土生和生物沉积物流入:每年1.65公里3/年.
- 估计的大陆积累速度:高达3.0公里3/年.
- 潜在的净大陆增长:1.35公里3/年.
结论:
- 俯冲区是大陆生长的重要地点.
- 沉积物流入和地回收有助于大陆积聚.
- 由于这些地质过程,地球的大陆呈现出净增长率.
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