作者: Barclay Kamb
DOI: 10.1007/978-94-015-8206-3_25
关键词: Mechanics 、 Glacier morphology 、 Geophysical fluid dynamics 、 Reynolds number 、 Mantle (geology) 、 Fluid dynamics 、 Convection 、 Geomorphology 、 Geology 、 Buoyancy 、 Incompressible flow
摘要: As a geophysical fluid dynamics phenomenon, glacier motion has features in common with some of the other terrestrial and planetary flows considered this book, but it also number special that give character its own. It can be compared to mantle flow convection: both involve slow essentially incompressible fluids very high viscosity, at low Reynolds number, negligible inertial, magnetic, Coriolis forces. The rheology is similar terms temperature dependence nonlinear stress dependence. Also, coupling heat usually important. A notable difference between problems nature boundary conditions: convection one assumes either no-slip condition or no-shear-stress base mass, whereas stress-controlled slip-rate required many cases; place specified-slip surface, surface always free. Another that, while types are response gravity as driving force, expressed buoyancy force mass loading, acts downslope body force. Glaciers often, ice sheets always, thin their horizontal dimensions, respect geometrical similarity “thin-skinned tectonics, ” or, on an even larger scale, tectonics earth’s crust distinct from mantle. Among tectonic phenomena most closely related detachment thrusting forms gravitational (Bucher, 1956; Hills, 1963, p. 79, 336; Suppe, 1985, 286). And course mechanics share ground dealing isostatic adjustment ice-sheet loading.