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

科学总结。在这项拟议的研究中，Fialko与Staudigel合作，他们提出了对Troodos蛇绿岩的垂直和横向堤防进行现场和理论研究的结合，并期望将其应用于中等和缓慢扩张的洋中脊。这项研究有三个相互关联的部分。首先，将改进筑堤的理论模型，放宽一些初始的简化，以期得到更适用于自然环境的结果。新的模式将包括更大范围的岩浆超压、沿轴的地形坡度和构造应力。此外，PI将纳入一些热效应，如温度依赖的岩浆流变学。在研究的第二部分，pi和一名学生将收集Troodos蛇绿岩岩脉的现有野外数据，并获取新的野外和实验室数据，以限制垂直侵入与横向侵入的岩浆量。他们还将改进现有的侵入中心模型，并区分岩浆（和化学）不同系统的行为。最后，在第三部分中，将Troodos数据与第一部分中建立的模型相结合，建立中缓扩展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如何向脊集中，岩脉的频率和体积关系，以及脊的岩浆和构造分割。

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.