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

University Of California-San Diego Scripps Inst Of Oceanography, La Jolla CA

Investigators

Abstract

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.