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Zur Vergleichbarkeit der magmatischen Gesteine aus dem Adamello mit den Tonalitgraniten aus den Hohen Tauern

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Upwelling and the distribution of chlorophyll a within the Bay of Concepción,Chile

The influence of upwelling on the distribution of chlorophyll a within the Bay of Concepción, Chile is discussed in light of continuous measurements of surface in vivo chlorophyll fluorescence and temperature taken simultaneously along horizontal transects, and hydrographic stations' data. Results suggest significant temporal variability both in the distribution of in vivo fluorescence, temperature and salinity within the Bay and in the characteristics of the exchange between the Bay and the adjacent shelf waters, induced by variable upwelling. Upwelling is produced by the predominant south-westerly winds during the summer. Significant variations in the wind direction occur with periods from two to seven days. During active upwelling, exchange is characterized by a surface outflow through the mouth of the Bay and an inflow at depth. Low chlorophyll fluorescence is confined to the upwelling areas on the eastern shore either within or outside the Bay; high chlorophyll fluorescence is confined to the central and western Bay. Density data suggest a three-layered circulation pattern at the mouth of the Bay during the upwelling relaxation involving an inflow both at the surface and bottom and outflow at mid-depth. Associated with this exchange is an active high chlorophyll transport from the Bay to the adjacent coastal waters at mid-depth and inflow of low chlorophyll water from the adjacent shelf at the surface and near the bottom.     

A semiobjective method for condensing classifications

A simple, semiobjective method is described to reduce the number of groups in a classification to an arbitrary level without losing contact with the geologic information contained in the evolving groups. The method, operated in a stepwise or cyclic manner, employs some of the commonly used numerical techniques, but avoids strict adherence to them to obtain geologically more meaningful results. The method is illustrated in a facies study of the upper Paleozoic rocks of southeastern Utah.     

Can gravitational effects damp Alfvén waves?

We show that Alfvén-gravity waves propagating in a gravitationally stratified atmosphere do not suffer damping as a result of the rate of working of the gravity drift current on the electric field of the waves. A self-consistent treatment involving conservation of total energy, Poynting's theorem, and the rate of working of the various drift currents on the electric field demonstrates that dissipation only arises from real dissipative processes such as Ohmic heating or viscous effects, otherwise the system is adiabatic.