概括
现代酸盐结节的增长缓慢,每千年增长一毫米,利用从底层沉积物中再生的. 这一过程与沉积积率快得多的沉积物形成鲜明对比,突出显示了沉积物内部的过程,而不是来自海水的直接沉.
科学领域:
- 海洋地质学 海洋地质学
- 地质化学 地质化学
- 海洋学 海洋学 海洋学
背景情况:
- 酸盐块是海洋外基矿物质,对于了解循环至关重要.
- 之前的研究还没有完全阐明现代酸盐的生长机制和来源.
- 沉积物积累速度可以显著变化,可能会影响结节的形成.
研究的目的:
- 为了确定现代海底酸盐结的生长速度.
- 为了确定的主要来源,以形成结节.
- 为了比较结节的生长率与底层沉积物的积累率.
主要方法:
- 对来自秘鲁海岸的现代酸盐结节的分析.
- 测量结节的生长速度.
- 测量底层沉积物的积累速度.
- 对孔水形状的分析,以推断溶解的酸盐流量.
主要成果:
- 酸盐块呈现缓慢的生长率 (每千年毫米).
- 结节的生长速度比沉积物积累速度慢几百倍.
- 在结节中的积累与沉积物中溶解的酸盐的向上扩散流相匹配.
结论:
- 现代酸盐结中的源于沉积物中的有机物质的再生.
- 结节的生长主要是由沉积物柱内的基因过程控制的,而不是来自底层水的直接沉.
- 这些发现为海洋循环和异性矿物形成提供了关键的见解.
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