The Diversity of Parent Magmas and the Role of Axial Magma Processes at a Fast Spreading Ridge: Evidence from Melt Inclusions & Near-Axis Seamount Lavas from the N. EPR

母岩浆的多样性和快速扩张山脊的轴向岩浆过程的作用：来自熔融包裹体的证据

• 批准号: 9730079
• 负责人: Roger Nielsen
• 金额: $ 12.01万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-06-01 至 2001-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9730079&HistoricalAwards=false
• 关键词: Diversity; Parent; Magmas; Role; Axial

9730079 Nielsen One of the primary reasons that geologists study basaltic lavas is their utility as probes of mantle and crustal processes. However, those very processes we wish to study erase the evidence of processes that are active earlier in the history of the magmatic system. One means by which magmas can be preserved is as melt inclusions and chemical zoning in crystals formed as the system evolves. Ideally, each inclusion represents a "snapshot" of the liquid trapped by the growth of the host crystal, preserving the character of intermediate steps in the formation of a suite of magmas. The goal of this research is to use information from melt inclusions from lavas sampled from areas on and near the East Pacific Rise characterized by different levels of magma flux, and from lavas erupted from volcanic centers near but not actually on the axis of the spreading center (off axis seamounts). This information will help us to evaluate the magnitude of the compositional heterogeneity in the mantle and of mantle versus crustal processes, and to better constrain models of how the mantle melts.

小行星9730079 地质学家研究玄武熔岩的主要原因之一是它们可以作为地幔和地壳过程的探针。 然而，我们希望研究的这些过程却抹去了岩浆系统历史上早期活动过程的证据。 岩浆得以保存的一种方式是作为熔体包裹体和在系统演化过程中形成的晶体中的化学分带。 理想情况下，每一个包裹体都代表了被主晶体生长所捕获的液体的“快照”，保留了一系列岩浆形成过程中中间步骤的特征。 本研究的目的是利用熔融包裹体的熔岩采样的东太平洋隆起地区和附近的特点是不同程度的岩浆流量，并从火山喷发的熔岩中心附近，但实际上不是在轴上的扩张中心（轴外海山）的信息。 这些信息将帮助我们评估地幔成分不均匀性的大小以及地幔与地壳过程的关系，并更好地约束地幔熔融的模型。