Mass Spectrometric Measurements of 231 Pa and 230 Th in the Water Column of the Tropical Atlantic: Evaluation of Water Mass Ventilation Ages and Boundary Scavenging

海洋学的经典问题之一是确定深环流的路径和速度。 各种地球化学示踪剂已被用来解决这个问题，但每一种似乎都提出了新的问题，每当他们被应用。 在这个项目中，伍兹霍尔海洋研究所的研究人员将继续开发一种新的分析技术，用于测量小体积海水中的230 Th和231 Pa，并建议将该技术应用于估计深水的通风年龄（即，向下混合之前所讨论的水团与大气接触的时间的反算）。 除了对深层西部边界流（DWBC）水的研究外，他们还将与其他同事合作，将该技术应用于从赤道大西洋断面收集的不同水团的样本，这些样本将提供比较性的氯氟烃（CFC）数据。 结合230/231与3 He/3 H，一个重要的老技术，和/或CFC数据，预计将澄清混合和源水同位素签名计算通风年龄的影响。

ABSTRACTOCE-9811260One of the classical problems of oceanography is determining the pathways and velocities of the deep circulation. Geochemical tracers of various types have been used to tackle this problem, but each of them seems to raise new questions whenever they are applied. In this project, researchers at the Woods Hole Oceanographic Institution will continue development of a new analytical technique for measuring 230Th and 231Pa in small volumes of seawater and propose to apply the technique to the estimation of ventilation ages of deep water (i.e., a back-calculation of the time when the water mass in question was in contact with the atmosphere before downmixing). Besides studies with Deep Western Boundary Current (DWBC) water, they will also apply the technique to samples from different water masses collected on an equatorial Atlantic transect in collaboration with other colleagues who will provide comparative chlorofluorocarbon (CFC) data. The combination of 230/231 with 3He/3H, an important older technique, and/or CFC data is expected to clarify the impact of mixing and source water isotopic signature on calculated ventilation ages.