The continental drift convection cell
MetadataShow full item record
Continents on Earth periodically assemble to form supercontinents and then break up again into smaller continental blocks (the Wilson cycle). Previous highly developed numerical models incorporate fixed continents while others indicate that continent movement modulates flow. Our simplified numerical model suggests that continental drift is fundamental. A thermally insulating continent is anchored at its center to mantle flow on an otherwise stress-free surface for infinite Prandtl number cellular convection with constant material properties. Rayleigh numbers exceed 107, while continent widths and chamber lengths approach Earth's values. The Wilson cycle is reproduced by a unique, rugged monopolar “continental drift convection cell.” Subduction occurs at the cell's upstream end with cold slabs dipping at an angle beneath the moving continent (as found in many continent/subduction regions on Earth). Drift enhances vertical heat transport up to 30%, especially at the core-mantle boundary, and greatly decreases lateral mantle temperature differences.
Author Posting. © American Geophysical Union, 2015. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 42 (2015): 4301-4308, doi:10.1002/2015GL064480.
Showing items related by title, author, creator and subject.
Munoz, Araceli; Cristobo, J.; Rios, P.; Druet, M.; Polonio, V.; Uchupi, Elazar; Acosta, Juan; Iglesias, S.; Portela, J.; del Rio, J. L.; Parra, S.; Sacau, M.; Vilela, R.; Patrocinio, T.; Almon, B.; Elvira, E.; Jimenez, P.; Fontan, A.; Alcala, C.; Lopez, V. (2012-05)The north flowing Falkland / Malvinas Current has generated sediment drifts at a depth of 1200-1600 m in the Patagonian middle continental slope out of early Holocene hemipelagics, late Pleistocene ice rafted clastics, and ...
Whitehead, John A.; Frazel, Robert E. (Woods Hole Oceanographic Institution, 1993-06)A laboratory model of wintertme cooling over a continental shelf has a water surface cooled by air in an annular rotating tank. A flat shallow outer "continental shelf" region is next to a conical "contiental slope" bottom ...
Drift and mixing under the ocean surface : a coherent one-dimensional description with application to unstratified conditions Rascle, Nicolas; Ardhuin, Fabrice; Terray, Eugene A. (American Geophysical Union, 2006-03-24)Waves have many effects on near-surface dynamics: Breaking waves enhance mixing, waves are associated with a Lagrangian mean drift (the Stokes drift), waves act on the mean flow by creating Langmuir circulations and a ...