Shear-Wave Splitting in Central Europe to Test Mantle-Upwelling Anisotropy Model

建议摘要EAR0107080(PH#20x)标题：中欧剪切波分裂以测试地幔上升各向异性模型PI：Simon L.Klemperer，Goetz Bokelmann，和Norman Sept，斯坦福大学关于地幔上升或“羽流”的性质有许多尚未解决的基本问题。具体地说，我们能否区分羽流模型，即从地幔较深部分涌出的物质，与作为地幔热点来源的替代模型？为了帮助回答这些问题，我们将对穿过上地幔的地震波进行剪切波分裂的测量。这些测量可以阐明与流动有关的地幔变形的几何形状，因为这种变形会导致地震各向异性--剪切波分裂的原因。然后，我们将把我们的数据与几种不同的羽流/岩石圈相互作用模型预测的数据进行比较。特别是，与夏威夷和黄石公园周围的测量结果一致的“抛物线软流层流动”模型将受到我们的数据的严格检验。尽管这些数据可能解决了诸如艾菲尔岩浆活动是否与莱茵格拉本伸展有关等地区性问题，但它们更根本地具有探测羽流存在的能力，回答了地球科学中一个悬而未决的问题。

Abstract for proposal EAR0107080 (PH #20x)Title: Shear-wave splitting in central Europe to test mantle-upwelling anisotropy modelPI's: Simon L. Klemperer, Goetz Bokelmann, and Norman Sleep, Stanford UniversityThere are a number of unresolved yet fundamental questions about the nature of mantle upwellings or "plumes". Specifically, can we distinguish the plume model, i.e., material upwelling from parts of the deeper mantle, from alternative models as a source for mantle hotspots? To help answer these questions, we will make measurements of shear-wave splitting for seismic waves that travel through the upper mantle. These measurements can illuminate the geometry of flow-related mantle deformation, since such deformation leads to seismic anisotropy--the cause of shear-wave splitting. We will then compare our data to those predicted by several different models of plume/lithosphere interaction. In particular, the "parabolic asthenospheric flow" model, which is consistent with measurements from around Hawaii and Yellowstone, will be critically tested by our data. Although these data may address regional problems such as whether there is a relation between Eifel magmatism and extension in the Rhine Graben, they more fundamentally have the ability to detect the existence of plumes, answering an outstanding question in the geosciences.