Collaborative Research: Geochemical Transect from Oceanic Adare Basin to Adjacent Continental Adare Peninsula: Implications for the Origin of Intraplate (HIMU-like) Alkaline Magmas

合作研究：从大洋阿代尔盆地到邻近的大陆阿代尔半岛的地球化学横断面：对板内（类 HIMU）碱性岩浆起源的影响

• 批准号: 0943503
• 负责人: Paterno Castillo
• 金额: $ 19.98万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2013-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0943503&HistoricalAwards=false
• 关键词: Collaborative; Research; Geochemical; Transect; Oceanic

Intellectual Merit: This proposal is for a combined geochronologic, petrographic, geochemical, and Sr-Nd-Pb-Os-O isotopic investigation of existing lava samples from the seamounts in the Adare Basin and from the adjacent continental Hallett Volcanic Province in Northern Victoria Land. A comparative study of contemporaneous intraplate oceanic and continental alkaline volcanism will be used to evaluate sources and processes responsible for magma production and differentiation. The seamount lavas will provide an opportunity to better characterize the composition of their underlying mantle source whereas the continental lavas will provide information on any effects of contamination by continental crust on their source signatures. The cause of Cenozoic magmatism in West Antarctica has been explained by a variety of models based primarily on geochemical evidence from continental volcanism. The proposed investigation will for the first time provide detailed geochronologic and geochemical data for both continental lavas and adjacent oceanic seamount lavas, thus offering a means by which to critically assess whether Cenozoic alkaline volcanism is due to plume or plume-related activities or magmatism unrelated to mantle plumes. The classic element of this controversy is whether the geochemistry of the magmas represents melting of mantle asthenosphere or subcontinental lithosphere and whether there is a degree of contamination as they rise through relatively thick and chemically heterogeneous continental crust. Broader impacts: This project will support a PhD and MSc student. Undergraduate students will also be involved in sample preparation, analytical work and interpretation via honors/senior theses. A post-doctoral associate will be involved in the oxygen isotopic analysis of the samples. The students will be involved in a multi-institutional and international collaboration. The geochemical database generated will be made available to other researchers in the region and the results will be published in peer-reviewed journals.

智力价值：这项建议是对来自阿达雷盆地海山和邻近的维多利亚北部大陆哈利特火山省的现有熔岩样品进行地质年代学、岩石学、地球化学和锶-钕-铅-Os-O同位素调查。将通过对同时代的板内、海洋和大陆碱性火山作用的比较研究，来评估岩浆产生和分异的来源和过程。海山熔岩将提供一个机会，更好地描述其下伏地幔来源的组成，而大陆熔岩将提供有关大陆地壳污染对其来源特征的任何影响的信息。西南极新生代岩浆活动的成因有多种模型，主要基于大陆火山活动的地球化学证据。拟议的调查将首次提供大陆熔岩和邻近海洋海山熔岩的详细地质年代学和地球化学数据，从而提供一种手段，用以严格评估新生代碱性火山活动是由于热柱还是与热柱有关的活动，还是由于与地幔热柱无关的岩浆作用。这场争论的经典元素是，岩浆的地球化学是代表地幔软流圈还是次大陆岩石圈的熔融，以及它们在相对较厚和化学不均匀的大陆地壳中上升时是否存在一定程度的污染。更广泛的影响：该项目将支持一名博士生和硕士研究生。本科生还将参与样品的准备、分析工作和通过荣誉/高级论文进行解释。一名博士后助理将参与样品的氧同位素分析。这些学生将参与一个多机构和国际合作。生成的地球化学数据库将提供给该区域的其他研究人员，其结果将发表在同行评议的期刊上。