Gravity-sediment flows

The type of sedimentary basin and its history of subsidence, heat flow and deformation are the main factors that determine the present-day hydrodynamic conditions in a basin. In the qualitative approach, the identification of the hydrodynamic conditions in present-day stable subaerial basins is restricted to the identification of the gravity-induced groundwater flow conditions. The identification of hydrodynamic conditions in sedimentary basins which are in whole or in part below sea level, should be based on the presupposition that both subsidence of and sedimentation in the basin as well as gravity-induced flow from continental areas surrounding the subaquatic part of the basin may have induced the present-day hydrodynamic conditions. In addition the potential influence of recent tectonic and/or magmatic activity should be taken into account. 

If the macromolecules are forced by some external agency to flow with a velocity V, light scattering can be used to measure this velocity. There are several possible examples of this (a) macromolecules suspended in a fluid which is in uniform motion with velocity Y, (b) macromolecules falling at their terminal velocities in a viscous solvent under the action of gravity (sedimentation velocity), (c) macroions accelerated to a terminal velocity by an externally imposed electric field (electrophoresis), and (d) macromolecules accelerated to their terminal velocity in an ultracentrifuge (sedimentation velocity). 

The chapter by Urdahl, Wayth, Fordedal, Williams, and Bailey begins by discussing droplet break-up processes under both laminar and turbulent flow conditions and in electrostatic fields. The authors then discuss the droplet coalescence process under normal Brownian motion, under gravity sedimentation, and in laminar shear, including turbulent collisions as well as collisions due to electrostatic forces. The remainder of the chapter is devoted to electrostatic-induced separation of the water-in-oil emulsions and emerging technologies. 

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