Investigating the birth and death of large igneous provinces

调查大型火成岩省的诞生和消亡

• 批准号: 249474-2008
• 负责人: Scoates, James
• 金额: $ 1.97万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=496928
• 关键词: Investigating; birth; death; large; igneous

Large igneous provinces (LIPs) consist of enormous emplacements of mafic extrusive and intrusive rocks, and they include such prominent features on Earth as continental flood basalts, oceanic plateaus, volcanic passive margins, submarine ridges, seamount chains, and perhaps some of the world's largest layered mafic-ultramafic intrusions. The major goals of the proposed field-petrologic-geochemical-isotopic-geochronologic research program address (1) how LIPs are initiated and how they are assembled, (2) how magmatism related to LIPs wanes and over what timeframe, and (3) whether two giant layered intrusions (Bushveld, Stillwater) represent the high-level cumulate reservoirs of LIPs? To address how LIPs are "born", the physical, chemical, and temporal architecture of the Triassic Karmusten flood basalts on Vancouver Island will be established to evaluate the mechanisms for assembly and growth of this immense accreted oceanic plateau. To address how LIPs "die", post-flood basalt intrusions from the Kerguelen Archipelago, a major oceanic island in the southern Indian Ocean, will be studied to determine what controls the origin and distribution of secondary magmatism, which occurs millions of years after the main magmatic activity ceases, in some LIPs. Given the very large volumes of basaltic magma produced over relatively short periods of geologic time, LIP magmatism represents a remarkably efficient process for the formation of basalt on Earth. The research program on these major large igneous provinces and layered intrusions will yield new samples, geochemical and geochronologic results, and interpretations that will significantly advance our knowledge of the internal evolution of these giant igneous bodies and the rates by which they form. The program will contribute directly to the training of 3 graduate and 3-4 undergraduate students, who will each be exposed to a wide range of research management, data analysis, and presentation skills that are in high demand from the mineral exploration industry, geological surveys, and research institutions worldwide.

大型火成岩省（LIPs）由镁铁质喷出岩和侵入岩的巨大侵位组成，它们包括地球上的突出特征，如大陆溢流玄武岩，海洋高原，火山被动边缘，海底脊，海山链，也许还有一些世界上最大的层状镁铁质-超镁铁质侵入体。建议的野外岩石学-地球化学-同位素-地质年代学研究计划的主要目标是：（1）LIPs是如何形成的以及它们是如何组合的;（2）岩浆活动与LIPs的关系如何减弱以及在什么时间段内减弱;（3）两个巨大的层状侵入体（布什维尔德、斯蒂尔沃特）是否代表LIPs的高水平累积储层？为了解决LIPs是如何“出生”的，物理，化学和时间架构的三叠纪卡穆斯滕洪水玄武岩的温哥华岛将建立评估组装和增长的机制，这个巨大的增生海洋高原。为了解决低密度行星如何“死亡”的问题，将研究南印度洋一个主要洋岛凯尔盖朗群岛洪水后的玄武岩侵入体，以确定是什么控制着次级岩浆活动的起源和分布，次级岩浆活动发生在一些低密度行星的主要岩浆活动停止数百万年之后。由于在相对较短的地质时期内产生了大量的玄武岩浆，LIP岩浆活动代表了地球上玄武岩形成的一个非常有效的过程。对这些主要的大型火成岩省和层状侵入体的研究计划将产生新的样品，地球化学和地质年代学结果，以及解释，这将大大提高我们对这些巨型火成岩体的内部演化及其形成速率的认识。该计划将直接有助于3名研究生和3-4名本科生的培训，他们每个人都将接触到广泛的研究管理，数据分析和演示技能，这些技能是矿产勘探行业，地质调查和研究机构的高需求。