Projects

Core Formation in the Lab
Sensitivity of a Coupled Earth System Model to Isopycnal Stirring
Climate interactions forced by continent assembly and breakup
The Young Inner Core
F-layer formation at the inner core boundary
How increasing mixing warms the polar regions
Modeling the Geodynamo
Global Paleobathymetry and Ocean Sediment Reconstruction
Magnetic Reversals and the Earth's Core
Geomagnetic Superchron Cycles Driven by Mantle Convection
Mantle convection, plates, and the Earth system
Geodynamic Carbon Cycling


Modeling the Geodynamo: Comparisons between a mantle-driven dynamo and the geomagnetic field


Core Mantle




The upper maps show the present-day geomagnetic field structure on the core-mantle boundary derived from satellite measurements (left), and the time average geomagnetic field structure for the past 5 million years (right; normal polarity times only).The lower maps are from a numerical dynamo that is driven by heat flow derived from our HF1 reconstruction of the 3D structure of the mantle. Note the close comparison between the major magnetic field structures in dynamo snapshot (left) and the present-day core field, and in the dynamo average (right) and the core field average.



References

0-5 Ma time average core field from: Johnson, C. L., G. Cromwell, L. Tauxe, C. G. Constable.
       Paleosecular Variation and Time-Averaged Field Behavior: Global and Regional
       Signatures, Abstract GP24A-02, Fall Meeting, American Geophysical Union.
       San Francisco, Calif., 3-7 December 2012.

HF1 dynamo from: Olson, P., Deguen, R., Hinnov, L.A., and Zhong, S., Controls on
       geomagnetic reversals and core evolution by mantle convection in the Phanerozoic
       dynamo, Phys. Earth. Planet. Inter. 214, 87-103, 2013.