What the mantle sees: the effects of continents on mantle heat flow
| Autor: | L. Guillou‐Frottier, Louis-Noel Moresi, Jean-Claude Mareschal, Claude Jaupart, Adrian Lenardic, W. M. Kaula |
|---|---|
| Přispěvatelé: | Department of Geology and Geophysics [Berkeley], University of California [Berkeley], University of California-University of California, Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), M. Richards et al. |
| Jazyk: | angličtina |
| Rok vydání: | 2000 |
| Předmět: |
010504 meteorology & atmospheric sciences
Mantle wedge [SDU.STU]Sciences of the Universe [physics]/Earth Sciences Geophysics 010502 geochemistry & geophysics 01 natural sciences Mantle (geology) Plate tectonics Mantle convection Heat flux 13. Climate action Lithosphere Hotspot (geology) Geology 0105 earth and related environmental sciences Earth's internal heat budget |
| Zdroj: | The history and dynamics of global plate motions M. Richards et al. The history and dynamics of global plate motions, American Geophysical Union, Washington D.C., pp.95-112, 2000, Geophysical Monograph 121 The History and Dynamics of Global Plate Motions |
| Popis: | The effects of continents on mantle heat flow are explored through a synthesis of heat flow data analysis and theoretical modeling. The data employed are from the Canadian Shield and the Canadian Appalachians and consist of both surface heat flow measurements and measurements of crustal heat production. The combined data sets, together with gravity and seismic information, which is used to help constrain crustal structure and composition, suggest that the mantle component of surface heat flow is low, between 10 and 15 mW/m 2 , and relatively uniform across a large portion of central to eastern Canada. Surface heat flow variations across the region covered can be well accounted for by observed variations in crustal heat production, i.e., no mantle heat flow variations need to be invoked. Laboratory experiments and numerical simulations, that explore the coupling between continents and the convecting mantle from a modeling based point of view, show how large, buoyant continents can locally constrain heat flux variations in the mantle below. Relative to what occurs in model oceanic regions, the equilibrium thermal condition imposed on the mantle by model continents is one of low and nearly uniform heat flux. Such a condition is consistent with the inferences drawn from the Canadian heat flow data. Theoretical models also imply that the local thermal constraint imposed on the mantle by continents can cause mantle heat flow to be relatively weakly correlated with tectonic age variations, lithospheric thickness variations, and local mantle flow patterns below tectonothermally stable continental regions. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|