Collaborative Research: Plume Tails and Continental Lithosphere: A Petrologic Transect of the Snake River Plain Between Mountain Home and Twin Falls, Idaho

9526723哈南这项建议的目的是调查地幔热柱动力学和大陆玄武岩之间的联系。地幔热柱、溢流玄武岩和板内海山链之间的拟议联系意味着，通过岩石圈越过地幔热柱而形成的火山岩将显示出不同的化学和同位素组成，这些成分随着地幔热柱的动力学以及热柱与上覆岩石圈之间的相互作用而变化。私家侦探们建议通过检测在爱达荷州斯内克河平原的山豪斯和双子瀑布之间的断面上发现的玄武岩熔岩的化学成分的时空变化来研究这一过程。从每个样品中选择的样品将通过X射线荧光光谱分析(USC)进行常量和微量元素地球化学分析；这些样品中具有代表性的一组样品将被选择用于额外的微量元素电感耦合等离子体质谱(ICPMS)和放射成因同位素(SDSU)的分析。P.I.计划使用39Ar/40Ar(伯克利地质年代学实验室)测定14个熔岩流的日期。这些数据将使我们能够评估玄武岩地幔源区的变化，并确定岩石圈和地壳同化的影响。

9526723 Hanan The object of this proposal is to investigate connections between the dynamics of mantle plumes and continental basalts. The proposed connection between mantle plumes, flood basalts, and intraplate seamount chains implies that volcanic rocks which form by passage of lithosphere over a mantle plume will display chemical and isotopic compositions which vary in response to plume dynamics and interactions between the plume and the overlying lithosphere. The P.I.s propose to investigate this process by examining spatial and temporal variations in the chemistry of basaltic lavas found in the Snake River Plain along a transect between Mountain Home and Twin Falls, Idaho. Selected samples from each will be analyzed for major and trace element geochemistry by XRF spectrometry (USC); a representative subset of these will be chosen for analysis of additional trace elements ICP-MS (Centenary),and radiogenic isotopes (SDSU). The P.I.s plan to date 14 lava flows using 39Ar/40Ar (Berkeley Geochronology Laboratory). These data will allow us to assess changes in the mantle source regions of the basalts, and to identify the effects of lithospheric and crustal assimilation.