Lithium Isotopic Investigations of Crustal Evolution

地壳演化的锂同位素研究

基本信息

  • 批准号:
    0948549
  • 负责人:
  • 金额:
    $ 44.62万
  • 依托单位:
  • 依托单位国家:
    美国
  • 项目类别:
    Continuing Grant
  • 财政年份:
    2010
  • 资助国家:
    美国
  • 起止时间:
    2010-03-15 至 2016-02-29
  • 项目状态:
    已结题

项目摘要

Intellectual Merit. Several lines of evidence point to an important role for chemical weathering in producing the bulk continental crust: [1] its composition is "andesitic", although the crust today, and likely since the Archean, grew by addition of basalt, [2] it is depleted in certain fluid-mobile elements relative to mantle-derived magmas (e.g., Sr, as seen in the crust's low Sr/Nd), 3) it has an oxygen isotopic composition heavier than that of the mantle (d18O ~9 vs. 6, respectively, due to lighter oxygen in water vs. rock), and 4) its has a lithium isotopic composition lighter than that of the mantle (d7Li ~1 vs. 4, respectively, due to heavier Li in water vs. rock). However, the mass of crust removed through chemical weathering is poorly constrained.It is proposed here to quantify the influence of weathering on the crust's composition through two parallel PhD projects that focus on Li isotopes and major and trace element geochemistry: [1] quantification of the weathering flux from basaltic continental crust, focusing on the Columbia River Basalts (CRB) in the Pacific NW, and [2] construction of a mass balance model for the bulk continental crust using lithium concentration ([Li]) and d7Li to determine the mass lost to the crust via weathering. The weathering flux from the continents and the attendant transformation of basalt to more Si-enriched regolith will be evaluated through a coupled study of in situ weathering and the riverine flux from the CRB. The strong rain shadow effect of the Cascade Mountains causes large variations in the weathering intensities of CRB basalts east and west of this range. Extensive laterites and bauxites formed on CRB from the wet, western side of the Cascades. In contrast, soil development and/or preservation is variable to the east due to differential exposure ages as a result of the massive flooding that occurred during the last ice age. Analyses of selected weathering profiles coupled with analyses of the fluvial flux in catchments that drain only CRB will be used to quantify the chemical flux and associated reactions attending basalt weathering. These data will be used to model the influence of weathering on continental crust composition. The non-basaltic composition of the continental crust was likely the consequence of the combined effects of delamination of mafic lower crust and removal of soluble components by weathering, but their relative contributions are poorly constrained. A mass balance model constructed to solve for the time-integrated chemical flux of weathering components from the continental crust using Li and its isotopes and accompanying sensitivity tests show that the calculated mass lost is highly sensitive to Li concentration in the bulk continental crust and juvenile crustal additions. These parameters will be estimated via analyses of deep crustal rocks as well as Archean Na-rich granites (trondhjemites, tonalites, granodiorites - TTG = putative slab melts additions to the continental crust). A parallel study of Li in shales through time will explore their utility as indicators of continental weathering intensity over geologic time.Broader Impacts. This project will support two PhD projects that are just underway. Several undergraduates will be involved in the research with the expectation that at least one senior thesis will result from this project. The project will support laboratory facilities used as a resource by numerous national and international visitors.
智力优点。几条证据表明,化学风化在产生大陆大陆壳中的重要作用:[1]它的组成是“安第斯山脉”氧同位素组成比地幔的氧同位素组成重(D18O〜9 vs. 6,由于水与岩石中的较轻氧)和4)其具有比地幔的同位素同位素组成更轻(D7li〜1 vs. 4)(由于水中的livier li vs. Rock)。 However, the mass of crust removed through chemical weathering is poorly constrained.It is proposed here to quantify the influence of weathering on the crust's composition through two parallel PhD projects that focus on Li isotopes and major and trace element geochemistry: [1] quantification of the weathering flux from basaltic continental crust, focusing on the Columbia River Basalts (CRB) in the Pacific NW, and [2] construction of a mass使用锂浓度([li])和D7LI来确定通过风化损失到地壳的质量的散装大陆地壳的平衡模型。将通过对现场风化的耦合研究和CRB的河流通量进行耦合研究,评估大陆的风化通量以及玄武岩向更富含Si-Ench的雷果的随之而来的盆地转化。喀斯喀特山脉的强烈雨阴影效应在此范围内的CRB玄武岩的风化强度中引起了巨大的变化。级联潮湿的西侧在CRB上形成的广泛的后矿石和铝土矿。相反,由于上次冰河时代发生的大规模洪水,由于暴露年龄的差异,土壤发育和/或保存是对东方的变化。对所选风化曲线的分析,以及对仅排水CRB的流域中的河流通量分析的分析,将用于量化化学通量和相关反应,并进行了玄武岩风化。这些数据将用于建模风化对大陆地壳组成的影响。大陆地壳的非质钙组成可能是镁铁质下壳分层和通过风化去除可溶性成分的结合作用的结果,但它们的相对贡献受到较差的约束。构建的质量平衡模型用于解决时间融合的化学通量,使用LI及其同位素和随附的灵敏度测试从大陆地壳中进行风化的组件,表明,计算出的质量损失对LI在散装大陆地壳和少年壳添加中的LI浓度高度敏感。这些参数将通过分析深层地壳岩石以及富丽堂内的花岗岩(Trondhjemites,Tonalites,Granodiorites -TTG =推定的大陆壳添加添加)。在时间上对Li的平行研究将探索它们的效用,作为大陆风化强度在地质时间上的指标。该项目将支持刚刚进行的两个博士学位项目。这项研究将参与一些大学生,并期望至少有一个高级论文是由该项目引起的。该项目将支持许多国家和国际游客用作资源的实验室设施。

项目成果

期刊论文数量(0)
专著数量(0)
科研奖励数量(0)
会议论文数量(0)
专利数量(0)

数据更新时间:{{ journalArticles.updateTime }}

{{ item.title }}
{{ item.translation_title }}
  • DOI:
    {{ item.doi }}
  • 发表时间:
    {{ item.publish_year }}
  • 期刊:
  • 影响因子:
    {{ item.factor }}
  • 作者:
    {{ item.authors }}
  • 通讯作者:
    {{ item.author }}

数据更新时间:{{ journalArticles.updateTime }}

{{ item.title }}
  • 作者:
    {{ item.author }}

数据更新时间:{{ monograph.updateTime }}

{{ item.title }}
  • 作者:
    {{ item.author }}

数据更新时间:{{ sciAawards.updateTime }}

{{ item.title }}
  • 作者:
    {{ item.author }}

数据更新时间:{{ conferencePapers.updateTime }}

{{ item.title }}
  • 作者:
    {{ item.author }}

数据更新时间:{{ patent.updateTime }}

Roberta Rudnick其他文献

Roberta Rudnick的其他文献

{{ item.title }}
{{ item.translation_title }}
  • DOI:
    {{ item.doi }}
  • 发表时间:
    {{ item.publish_year }}
  • 期刊:
  • 影响因子:
    {{ item.factor }}
  • 作者:
    {{ item.authors }}
  • 通讯作者:
    {{ item.author }}

{{ truncateString('Roberta Rudnick', 18)}}的其他基金

Collaborative Research: Halogen and chlorine isotope behavior during metamorphism of metapelitic rocks
合作研究:变质岩变质作用过程中的卤素和氯同位素行为
  • 批准号:
    2321367
  • 财政年份:
    2023
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Standard Grant
How do sedimentary rocks become part of the lower continental crust?
沉积岩如何成为下大陆地壳的一部分?
  • 批准号:
    2148886
  • 财政年份:
    2022
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Standard Grant
2019 Interior of the Earth GRC/GRS
2019 地球内部 GRC/GRS
  • 批准号:
    1918478
  • 财政年份:
    2019
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Standard Grant
Chalcophile Element Geochemistry
亲铜元素地球化学
  • 批准号:
    1757313
  • 财政年份:
    2018
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Standard Grant
U-Pb Thermochronology of Lower Crustal Xenoliths: Estimating Moho Temperature in Order to Constrain Crustal Heat Production
下地壳包体的 U-Pb 热年代学:估算莫霍面温度以限制地壳产热
  • 批准号:
    1650260
  • 财政年份:
    2017
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Continuing Grant
Li Isotope Behavior in Zircons, with Implications for the Hadean Earth
锆石中的锂同位素行为,对冥宙地球的影响
  • 批准号:
    1551388
  • 财政年份:
    2016
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Standard Grant
Constraining the Secular Compositional Evolution of the Upper Continental Crust Using Ancient Glacial Deposits and Creation of an Upper Crustal Reference Suite
利用古冰川沉积物约束上陆壳的长期成分演化并创建上地壳参考套件
  • 批准号:
    1321954
  • 财政年份:
    2013
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Standard Grant
PGE, Re-Os and Lu-Hf Isotopic Signature of Lithosphere Removal Beneath the North China Craton
华北克拉通岩石圈去除的PGE、Re-Os和Lu-Hf同位素特征
  • 批准号:
    0911096
  • 财政年份:
    2009
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Standard Grant
The Timing and Geometry of Lithosphere Removal Beneath the North China Craton
华北克拉通岩石圈去除的时间和几何形状
  • 批准号:
    0635671
  • 财政年份:
    2007
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Continuing Grant
Determining the Processes Responsible for Lithium Isotope Fractionation
确定负责锂同位素分馏的过程
  • 批准号:
    0609689
  • 财政年份:
    2006
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Continuing Grant

相似国自然基金

桂东北加里东期李家锡矿精细成矿过程:来自锡石和电气石微区元素和同位素的制约
  • 批准号:
    42302109
  • 批准年份:
    2023
  • 资助金额:
    20 万元
  • 项目类别:
    青年科学基金项目
过渡金属掺杂型分子筛膜的制备与氢同位素气体分离
  • 批准号:
    22375031
  • 批准年份:
    2023
  • 资助金额:
    50 万元
  • 项目类别:
    面上项目
氮同位素约束的海洋固氮与输出生产力耦合关系研究
  • 批准号:
    42376140
  • 批准年份:
    2023
  • 资助金额:
    51 万元
  • 项目类别:
    面上项目
南海北部“海马”与“F站位”冷泉生物的元素和同位素地球化学特征及其对甲烷来源的示踪
  • 批准号:
    42372161
  • 批准年份:
    2023
  • 资助金额:
    53 万元
  • 项目类别:
    面上项目
扬子克拉通西缘深成造山型丹巴金矿成矿流体多组分源区同位素示踪
  • 批准号:
    42372109
  • 批准年份:
    2023
  • 资助金额:
    53 万元
  • 项目类别:
    面上项目

相似海外基金

OCE-PRF Isotopic and microbial investigations of the iron geochemistry and bioavailability of glaciogenic particles
OCE-PRF 冰川形成颗粒的铁地球化学和生物利用度的同位素和微生物研究
  • 批准号:
    2126562
  • 财政年份:
    2021
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Standard Grant
Doctoral Dissertation Research: Genetic and Isotopic Investigations of Human Population Origins and Dispersals in Island Settings
博士论文研究:岛屿环境中人类起源和扩散的遗传和同位素研究
  • 批准号:
    1848513
  • 财政年份:
    2019
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Standard Grant
Formation and impact histories of the Solar System and planets from chemical and isotopic investigations of planetary materials
通过行星材料的化学和同位素研究,了解太阳系和行星的形成和撞击历史
  • 批准号:
    RGPIN-2014-06310
  • 财政年份:
    2019
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Discovery Grants Program - Individual
Formation and impact histories of the Solar System and planets from chemical and isotopic investigations of planetary materials
通过行星材料的化学和同位素研究,了解太阳系和行星的形成和撞击历史
  • 批准号:
    RGPIN-2014-06310
  • 财政年份:
    2018
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Discovery Grants Program - Individual
Formation and impact histories of the Solar System and planets from chemical and isotopic investigations of planetary materials
通过行星材料的化学和同位素研究,了解太阳系和行星的形成和撞击历史
  • 批准号:
    RGPIN-2014-06310
  • 财政年份:
    2017
  • 资助金额:
    $ 44.62万
  • 项目类别:
    Discovery Grants Program - Individual
{{ showInfoDetail.title }}

作者:{{ showInfoDetail.author }}

知道了