Geochemical Evolution of the Galapagos Hotspot

来自加拉帕戈斯群岛的9418889库尔茨初步数据证明了氦对了解地幔过程的重要性。虽然高的3He/4He比值本身很重要，但这个项目的重点是了解局部变化，并将它们与羽流内的过程联系起来。这项拟议工作的一个特别重要的方面是，宇宙射线产生的3He可以用来确定年龄，从而提供年龄控制。这将是一种综合方法，将实地工作、常量元素和微量元素测量以及氦、锶、钕和铅的同位素与地表暴露测年提供的年代学结合起来。这项工作将与Dennis Geist(爱达荷大学)合作进行，Dennis Geist在加拉帕戈斯有长期的实地工作记录。这项研究的目标是：1.利用地表暴露测年技术评估加拉帕戈斯火山热点和单个火山中心的时间演化。通过结合年表获得地球化学数据，严格测试群岛内总体梯度的各种模型，应该是可能的。2.记录群岛内的氦同位素变异性。

9418889 Kurz Preliminary data from the Galapagos demonstrate the importance of helium to understanding mantle processes. Although the high 3He/4He ratios alone are important, the focus of this project is to understand the local variations, and relate them to processes within the plume. A particularly important aspect of the proposed work is that cosmic ray produced 3He can be used to determine ages, thus providing age control. This will be an integrated approach that will combine field work, major and trace element measurements, and the isotopes of He, Sr, Nd and Pb, with chronology provided by surface exposure dating. This work will be carried out in collaboration with Dennis Geist (University of Idaho) who has a long record of field work in the Galapagos. The goals of the proposed research are to: 1. Evaluate the temporal evolution of Galapagos hotspot, and individual volcanic centers using surface exposure dating. By obtaining the geochemical data in conjunction with chronology to rigorously test the various models for the overall gradients within the archipelago it should be possible. 2. Document the helium isotopic variability within the archipelago.