Shear flow beneath oceanic plates: Local nonsimilarity boundary layers for olivine rheology

Journal Article · Fri Feb 10 04:00:00 EST 1978 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JB083iB02p00759· OSTI ID:5088571

Yuen, D A; Tovish, A; Schubert, G

The principle of local similarity, which has been used to model the two-dimensional boundary layers in the oceanic upper mantle, permits calculation of the temperature, velocity, and stress fields with essentially analytic techniques. Finite difference numerical methods are hard pressed to resolve the detail required by the large variation of viscosity between the lithosphere and the asthenosphere. In this paper the local similarity approximation has been justified by quantitatively evaluating the effect of nonsimilarity due to viscous heating, nonlinear temperature- and pressure-dependent rheology, buoyancy, adiabatic cooling, etc. Nonsimilar effects produce only small modifications of the locally similar boundary layers; important geophysical observables such as surface heat flux and ocean floor topography are given to better than 10% by the locally similar solution. A posteriori evaluations of the term neglected in the boundary layer simplification of the complete equations have been conducted on the locally similar temperature and velocity profiles close to the spreading ridge. The boundary layer models are valid to depths of 100 km at 3 m.y. and 10 km at 0.3 m.y.

• Research Organization: Department of Earth and Space Sciences, University of California, Los Angeles, California 90024
• OSTI ID: 5088571
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 83:B2; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580100 -- Geology & Hydrology-- (-1989)
580500* -- Oceanography-- (1980-1989)
ADIABATIC PROCESSES
BOUNDARY LAYERS
CONVECTION
EARTH MANTLE
ENERGY TRANSFER
HEAT TRANSFER
LAYERS
MASS TRANSFER
OCEANOGRAPHY
OLIVINE
PRESSURE DEPENDENCE
SEA BED
STRESSES
TEMPERATURE DEPENDENCE
TOPOGRAPHY
TWO-DIMENSIONAL CALCULATIONS