Fresh water seepage and pore water recycling on the seafloor: Sagami Trough subduction zone, Japan
Fresh water seepage and pore water recycling on the seafloor: Sagami Trough subduction zone, Japan
复制标题
海底淡水渗流和孔隙水循环利用：日本相模海槽俯冲带
DOI：
10.1016/0012-821x(95)00228-5
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发表时间：
1996
影响因子：
5.3
通讯作者：
Tomoki Nakamura
中科院分区：
文献类型：
--
作者：
U. Tsunogai;J. Ishibashi;H. Wakita;T. Gamo;T. Masuzawa;T. Nakatsuka;Y. Nojiri;Tomoki Nakamura
为了弄清流体渗漏的来源，我们利用日本的Shinkai 2000号潜水器，在菲律宾板块北端Sagami海槽的半深海Calytogena社区区域(Hatsushima区域)采集了19个底层海水样品(包括8个闪亮的流体样品)。闪闪发光的流体样品的最高温度为11.6℃，比周围海水高出约9℃。这些样品的流体化学特征如下：(1)与周围海水相比，碱度、H_2S、SiO_2、NH_4、Σ、CO_2和CH_4呈富集状态，而Cl、SO_4、K、Na、Mg和Ca呈亏损状态；(2)Cl亏损约20%；海水、孔隙水和陆源地下水的混合很好地解释了所观察到的流体的化学成分和温度，其温度约为40°C，每天的渗透通量约为400立方米。对全球化学通量的初步估计表明，地下水向海洋的排放(包括孔隙水循环)是控制海洋化学的一个重要因素。
We collected 19 samples of bottom sea water (including 8 samples of shimmering fluid), using the Japanese submersible Shinkai 2000, in the bathyal Calyptogena community area (the Hatsushima area) along Sagami Trough, at the northern end of the Philippine Sea plate, in order to clarify the source of fluid seepage. Shimmering fluid samples showed a maximum temperature of 11.6°C, which is about 9°C higher than the ambient sea water. The fluid chemistry of these samples is summarized as follows: (1) alkalinity, H2S, SiO2, NH4, ΣCO2and CH4show enrichment and Cl, SO4, K, Na, Mg and Ca show depletion compared with ambient sea water; (2) Cl depletion is about 20%; and (3) the content and3He4He ratio of dissolved helium show little anomaly compared with ambient sea water. The observed chemical composition and temperature of the fluid is well explained by mixing of sea water, pore water and land-derived groundwater with a temperature of about 40°C and a seeping flux of about 400 m3per day. A preliminary estimation of the global chemical flux implies that groundwater discharge to the ocean (including pore water recycling) is an important factor in controlling ocean chemistry.