Talk IGC meeting
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The document discusses how dynamic processes affect the relationship between seafloor age and area over time. It finds that plate tectonics and continental drift, through processes like ridge formation, rifting, dispersal, and aggregation, change the age distribution of ocean floors in a time-dependent way. The distribution evolves through alternating periods of high and low heat flow associated with Wilson cycles of plate boundary reorganizations. 3D spherical convection models that include plate-like behavior or drifting continents are needed to reproduce the young ages of subducted seafloor implied by constraints.
Talk IGC meeting
- 2. Dynamic causes of the relation between area and age of the oceanfloor N. Coltice, T. Rolf, P.J. Tackley, S. Labrosse Science (336) – April 2012
- 6. Time dependent Time 1 Time 2
- 7. Estimatedevolution of the age distribution Becker et al., 2009
- 8. 3D spherical convection withplate-likebehavior and continental rafts
- 10. Age (Myrs)
- 11. Age (Myrs)
- 12. Age (Myrs)
- 14. Wilson cycle model High heat flow Moderateheat flow New ridges - rifting Dispersal Lowheat flow Aggregation
- 15. Conclusions •Seafloor age constraint: continents and plate-like behavior are needed for young seafloor “subduction” • Formation of plate boundaries and continental aggregation/dispersal change the age distribution • Time dependence of the distribution is the rule • Distribution changes its shape through Wilson cycles
- 17. 3D sphericalwithplate-likebehavior OR with continents (no plate-likebehavior)