Temperature beneath continents as a function of continental cover and convective wavelength

• Published in: Journal of Geophysical Research
• Main Authors: Philipps, Benjamin R., Coltice, Nicolas
• Other Authors: Earth and Environmental Sciences Division Los Alamos, Los Alamos National Laboratory (LANL), Laboratoire de Sciences de la Terre (LST), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Los Alamos National Laboratory, National Science Foundation
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2010
• Subjects: MANTLE CONVECTION; HEAT-FLOW; SUPERCONTINENT CYCLES; DEPENDENT VISCOSITY; THERMAL-CONVECTION; RAYLEIGH NUMBER; PLATE MOTIONS; POLAR WANDER; DEEP MANTLE; MODELS; [SDU.STU]Sciences of the Universe [physics]/Earth Sciences; Antarc*; Antarctica
• Online Access: https://hal.archives-ouvertes.fr/hal-00687078; https://hal.archives-ouvertes.fr/hal-00687078/document; https://hal.archives-ouvertes.fr/hal-00687078/file/2009JB006600.pdf; https://doi.org/10.1029/2009JB006600

International audience Geodynamic modeling studies have demonstrated that mantle global warming can occur in response to continental aggregation, possibly leading to large-scale melting and associated continental breakup. Such feedback calls for a recipe describing how continents help to regulate the thermal evolution of the mantle. Here we use spherical mantle convection models with continents to quantify variations in subcontinental temperature as a function of continent size and distribution and convective wavelength. Through comparison to a simple analytical boundary layer model, we show that larger continents beget warming of the underlying mantle, with heating sometimes compounded by the formation of broader convection cells associated with the biggest continents. Our results hold well for purely internally heated and partially core heated models with Rayleigh numbers of 10(5) to 10(7) containing continents with sizes ranging from that of Antarctica to Pangea. Results from a time-dependent model with three mobile continents of various sizes suggests that the tendency for temperatures to rise with continent size persists on average over timescales of billions of years.