Vertical averages of rheology of the continental lithosphere: relation to thin sheet parameters

摘要: Abstract We calculate vertically-averaged rheologies for continental lithosphere subject to biaxial states of stress corresponding extensional, compressional, and strike-slip regimes. assume that brittle deformation occurs by Byerlee's Law ductile steady-state creep mechanisms. Under these conditions, the rheology may be approximated a single power law over range strain rates from 10−13 10−17 s−1. This is true not only when either or behavior dominates strength lithospere, but also contributions are comparable. The value exponent,n, depend on: depth difference at brittle-ductile transition, temperature Moho, geothermal gradient. In vertically-integrated between 1012 1013 N m−1n reaches minimum 5 10; under other circumstancesn increases rapidly as behavior. depends most strongly on thermal state upper mantle influenced supported in portions lithosphere.