The Role of High- and Low-Temperature Ocean Crust Alteration for the Marine Calcium Budget

高温和低温洋壳变化对海洋钙预算的作用

• 批准号: 5414771
• 负责人: Professor Dr. Anton Eisenhauer
• 金额: --
• 依托单位: GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2003
• 资助国家: 德国
• 起止时间: 2002-12-31 至 2006-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5414771?language=en
• 关键词: Role; Low; Temperature; Ocean; Crust

The circulation of seawater through hydrothermal systems at mid-ocean ridges has been proposed as a source for calcium (Ca) which is a major chemical constituent of seawater controlling oceans alkalinity and climate change. Although oceans alkalinity and Ca concentrations are supposed to be directly linked to each other it has been shown that deep ocean water contain higher levels of dissolved Ca than expected from calcium carbonate (CaCO3 dissolution only). The magnitude of the anomalies suggests that fluxes associated with the low-temperature circulation of seawater at mid-ocean ridge systems are much larger than previously thought. In particular, the role of low temperature alteration of basalts has been unterestimated in this respect. In order to better understand the processes of chemical alteration and to better constrain the mass balance of Ca in the ocean this project will study the Ca cycle during high and low-temperature alteration at mid ocean ridges.

海洋中脊热液系统的海水循环被认为是钙（Ca）的来源，而钙是控制海洋碱度和气候变化的主要海水化学成分。虽然海洋的碱度和钙浓度被认为是直接相关的，但已经证明，深海中溶解的钙含量高于碳酸钙（仅溶解CaCO3）的预期水平。这些异常的幅度表明，与海洋中脊系统的海水低温环流有关的通量比以前认为的要大得多。特别是玄武岩低温蚀变的作用在这方面被低估了。为了更好地了解海洋化学蚀变过程，更好地约束海洋中Ca的质量平衡，本项目将研究洋中脊高低温蚀变过程中的Ca循环。