REU: Evolution of the Kerguelen Plume: Studies of Mafic Rocks From the Northern Kerguelen Plateau

REU：凯尔盖朗地幔柱的演化：凯尔盖朗高原北部镁铁质岩石的研究

• 批准号: 9814313
• 负责人: Frederick Frey
• 金额: --
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-01-01 至 2002-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9814313&HistoricalAwards=false
• 关键词: REU; Evolution; Kerguelen; Plume; Studies

9814313FreyOver the past 115 My a significant fraction of the eastern Indian Ocean seafloor was formed by magmas derived from the Kerguelen mantle plume. The overall goal of this research is to use this volcanic record to understand the origin and evolution of the Kerguelen mantle plume. This is an important objective because magmas derived from mantle plumes provide information about physical and chemical processes occurring in the earth's mantle that cannot be obtained from study of volcanism associated with diverging and converging plates. Specifically, mantle plumes provide information about convection processes in the mantle, and the effects of long-term recycling of crust into the mantle. The Kerguelen Plume is particularly important because: (a) it is long-lived; (b) all aspects of plume-related volcanism are accessible for study; i.e., a very large igneous province (Kerguelen Plateau) which is commonly associated with plume initiation, a long hotspot track of volcanoes (Ninetyeast Ridge) which formed as the Indian plate migrated rapidly northwards over the plume, and a large, recently active oceanic island (Kerguelen Archipelago) located on the Antarctic Plate; (c) lavas associated with this plume have a distinctive geochemical signature which reflect recycling of crust into the deep mantle; (d) formation of the large igneous province in the newly formed relatively small Indian Ocean may have enabled dispersal of these plume geochemical characteristics into the Indian Ocean asthenosphere, thereby creating the distinctive geochemical characteristics of basalts erupted at currently active seafloor spreading centers in the Indian Ocean; and (e) the high magma flux reflected by the mid-Cretaceous formation of the Southern Kerguelen Plateau may have significantly affected the earth's hydrosphere/atmosphere system. Geochemical and age data for igneous rocks from the Kerguelen Archipelago and submarine Northern Kerguelen Plateau will be obtained in order to understand the source and evolution of the 40 My volcanism related to the Kerguelen Plume.

9814313过去115我在印度洋海底的大部分是由源自kerguelen披风羽流的岩浆形成的。 这项研究的总体目的是利用该火山记录来了解Kerguelen地幔羽的起源和演变。 这是一个重要的目标，因为从地幔羽流得出的岩浆提供了有关地球披风中发生的物理和化学过程的信息，这些信息无法从与散落和收敛板相关的火山研究中获得。 具体而言，地幔羽提供了有关地幔中对流过程的信息，以及将外壳回收为地幔的影响。 Kerguelen羽流特别重要，因为：（a）它是长寿的； （b）可以研究与羽流相关的火山的所有方面；即，一个非常大的火成岩省（Kerguelen高原）通常与羽状启动有关，这是一条长长的火山的热点（九十年山脊），它形成，当印度板在羽流上迅速向北迁移，以及一个近来的，最近活跃的海洋岛（Kerguelen群岛）（Kerguelen群岛）（Kerguelen群岛）（Kerguelen群岛）； （c）与此羽流相关的熔岩具有独特的地球化学特征，反映了地壳在深陆壁上的回收； （d）在新形成的相对较小的印度洋中形成大型火成岩省，可能使这些羽状地球化学特征分散到印度洋助理，从而使玄武岩的独特地球化学特征在当前活跃的海藻蔓延中爆发出独特的地球化学特征； （e）南部凯格伦高原的白垩纪形成反射的高岩浆通量可能会显着影响地球水圈/大气系统。将获得来自Kerguelen群岛和海底Kerguelen高原潜艇的火成岩岩石的地球化学和年龄数据，以了解与Kerguelen羽流有关的40座我的火山污染的来源和演变。