Along-Axis Variations in Magma Production and Delivery at Slow & Intermediate Spreading Ridges: Constraints from Theoretical Modeling & Field Observations in the Troodos O

岩浆产生和输送的慢速沿轴变化

• 批准号: 0137226
• 负责人: Yuri Fialko
• 金额: $ 18.71万
• 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: 2002
• 资助国家: 美国
• 起止时间: 2002-02-15 至 2005-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0137226&HistoricalAwards=false
• 关键词: Along; Axis; Variations; Magma; Production

Science Summary. In this proposed study, Fialko has teamed with Staudigel and they propose a combined field and theoretical study of vertical and lateral diking at the Troodos ophiolite with expected applications to medium and slow spreading mid-ocean ridges. The study has three connected parts. First, theoretic models of diking will be improved and some initial simplifications will be relaxed to hopefully yield results more applicable to natural settings. New models will incorporate a wider range of magmatic overpressures and along-axis topographic slopes and tectonic stress. In addition, the PI will incorporate some thermal effects such as temperature dependent magma rheology. In the second part of the study, the PIs and a student will compile existing field data for dikes from the Troodos ophiolite, and acquire new field and lab data to constrain the amounts of magma that are intruded vertically versus laterally. They will also refine existing models of intrusive centers and distinctions between the behaviors of magmatically (and chemically) distinct systems. Finally, in the third part, the Troodos data will be combined with the models developed in the first part to produce forward models for the diking behavior of medium and slow-spreading ridges. A number of natural phenomena can be explored with these models to gain a deeper understanding of how magma is focused toward ridges, the frequency and volume relations of diking, and magmatic and tectonic segmentation of ridges.

科学摘要。在这项拟议的研究中，Fialko与Staudigel合作，他们提出了一项关于Troodos蛇绿岩垂直和横向堤防的现场和理论研究相结合的研究，预计将应用于中等和缓慢扩展的大洋中脊。这项研究有三个相互关联的部分。首先，将改进堤防的理论模型，放宽一些最初的简化，希望得到更适合自然环境的结果。新的模型将纳入更大范围的岩浆超压和沿轴的地形坡度和构造应力。此外，PI还将包含一些热效应，如随温度变化的岩浆流变学。在研究的第二部分，PI和一名学生将汇编来自特罗多斯蛇绿岩的现有岩脉现场数据，并获得新的现场和实验室数据，以限制垂直与横向侵入的岩浆数量。他们还将完善现有的侵入中心模型，以及魔法(和化学)截然不同的系统行为之间的区别。最后，在第三部分中，Troodos数据将与第一部分中开发的模型相结合，生成中速扩展山脊的堤防行为正演模型。利用这些模型可以探索许多自然现象，从而更深入地了解岩浆是如何向山脊集中的，堤坝的频率和体积关系，以及山脊的岩浆和构造分段。