Collaborative Research: The Flood Basalt-Alkalic Magmatism-Kimberlite Connection and the Temporal-Spatial Evolution of the Siberian Mantle Plume

合作研究：溢流玄武岩-碱性岩浆作用-金伯利岩联系与西伯利亚地幔柱的时空演化

• 批准号: 9527053
• 负责人: Asish Basu
• 金额: $ 15.29万
• 依托单位: University of Rochester
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-08-01 至 1999-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9527053&HistoricalAwards=false
• 关键词: Collaborative; Research; Flood; Basalt; Alkalic

9527053 Basu This project is to conduct a multi-disciplinary study of field, petrologic, geochemical. isotopic and geochronological study of a suite of ultrabasic-alkaline and mafic rocks of Maimecha-Kotui region of the northern Siberian platform. The volcano-plutonic complexes of this region are closely associated in time and space with the Siberian Flood Basalt Province (SFBP) of permo-Triassic age. As part of this study The P.I.s will also include the kimberlites with the alkalic and tholeiitic pulses of the SFBP mantle plume. Preliminary data on 3He/3He measurements in olivines of the alkalic rocks suggest a lower mantle source for the 3He and links the alkalic-Maimecha phase to the plume-related SFBP. More noble gas isotope ratio measurements (He, Ne, Ar and Xe) are needed for confirmation. 40Ar/39Ar age dating of kimberlites and of the ultrabasic-alkaline and mafic rocks of the 2.8 km thick Maimecha-Kotui volcanic section are proposed to determine age and duration of volcanism. Nd, Sr, Pb-isotopic and trace elemental analyses, including the rare earth elements by TCP-MS, will also be performed on these rocks during the two-year tenure of the grant period. The analytical results will be used to examine whether there is a common petrogenetic link (e.g., mantle-derived plume) for the origin of the Kharamai kimberlites, the ultrabasic-alkaline and mafic volcanic rocks of the Maimecha-Kotui section, and for the voluminous, predominantly tholeiitic SFBP. In the event that these data do not support such a hypothesis, the acquired date will still be useful in formulating and substantiating other petrogenetic models.

9527053 BASU这个项目是为了对岩石学，地球化学的田间进行多学科研究。西伯利亚北部平台的Maimecha-Kotui地区的超静脉和镁铁质岩石的同位素和年代学研究。 该地区的火山 - 平地复合物在时间和空间上与渗透年龄的西伯利亚洪水盆地省（SFBP）密切相关。 作为这项研究的一部分，P.I.S还将包括SFBP地幔的碱性和Tholeiitic脉冲的金伯利岩。 碱岩石橄榄石中3HE/3HE测量的初步数据表明，3HE的地幔源较低，并将碱性 - 米马时期与羽流相关的SFBP联系起来。 需要更多贵重的气体同位素比测量值（HE，NE，AR和XE）进行确认。 提出了2.8 km厚的Maimecha-kotui火山区的40AR/39AR年龄的年龄，以及2.8 km厚的Maimecha-kotui火山段的超静氨酸和镁铁质岩石的年龄。 在赠款期的两年任期内，也将在这些岩石上进行ND，SR，PB - 异位和痕量元素分析，包括TCP-MS的稀土元素。 分析结果将用于检查有关Kharamai Kimberlites的起源，Maimecha-Kotui剖面的超级碱性和火山岩的起源，以及大量的，大量的，大量的theoleientiel theoleientiel theoleiities sfbbp。 如果这些数据不支持这种假设，则获得的日期仍将在制定和证实其他岩性模型中有用。