Multi-Scale Physics of the Core-Mantle Boundary Region

2023 Fiscal Year Research-status Report

• Project/Area Number: 23K03525
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: ハーンルンド ジョン 東京工業大学, 地球生命研究所, 教授 (30723712)
• Project Period (FY): 2023-04-01 – 2028-03-31
• Keywords: Mantle Convection / Layered Convection / Lubrication Theory

Outline of Annual Research Achievements

We performed 2D numerical simulations of mantle convection with a dense layer in to compare with predictions of lubrication theory. We tested the influence of simple shear stresses to support and shape dense layer morphology, and found that simple shear has no influence on chemical layer morphology, only normal stresses are important. This is a significant first result, and we can use it to build new scaling relations for the general case.

Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

The results obtained thus far are important, however, it is only a small part of the larger project. I have 4 masters students at the moment, so their progress is gradual, but this will improve as they gain experience. They are working with me on multiple aspects of the problem, and we aim to construct an entire ecosystem of models based on multi-scale physics.

Strategy for Future Research Activity

Our key results so far have been obtained on the mantle side, however, another key aspect of this problem is the outermost core. I have a masters student working on large scale dynamo models to understand the background flow and state of the core under the influence of layering and lateral flux variations. He is presently working on 1D models that are closely analogous to the physics of the upper mixed layer of surface ocean dynamics. We aim to using our hybrid multi-scale approach to understand the evolution of the system while leveraging the advantages of each technique.