Osmium Isotopes in Mid-Ocean Ridge Hydrothermal Systems

9504276 Ravizza Ravizza计划收集热液和烟囱样本，用于分析铂族元素、铼和锇同位素。我们对这些元素的全球循环知之甚少，河流输入的这些金属似乎比沉积在沉积物中的要多。在过去的6000万年里，海水中的锇同位素比例发生了巨大的变化，一些科学家认为这是由于大陆风化作用的增加。了解Os的来源和汇对评价这一过程具有重要意义，热液喷口和矿床可能是Os的主要汇。＊＊＊

9504276 Ravizza Ravizza plans to collect hydrothermal water and chimney samples for analysis for the platinum group elements, rhenium and osmium isotopes. We have little understanding of the global cycling of these elements and there appears to be more of these metals being inputted by rivers than is being deposited into sediments. The osmium isotope ratio in sea water has changed dramatically in the past 60 million years which some scientists have attributed to an increase in continental weathering. Understanding the sources and sinks of Os will be important for evaluating this process, and hydrothermal vents and deposits may be a major sink for Os. ***