Die Unterschiede in den Sedimentationsvorgängen zwischen dem Autunien und Saxonien von Mittel- und Westeuropa

After a comment on the stratigraphical classification and the subdivision of Permian strata, a review on their occurrences in Central and Western Europe including the Alps is given. Within this area, the strata can be summarized to a northern, a central, and a “Verrucano” province. The Autunian (Lower Rotliegend) has been typically developed in the central province where it is best preserved. It is characterized by many different sedimentation processes the most important of which are described. They lead to the conclusion that the sediment deposition mainly took place in fresh water lakes and through fluviatile transport. On the other hand, the deposition of the Saxonian (Upper Rotliegend) took place in a much drier climate. Finally, the differences between the two types of climate are described.     

Can coronal loop transients be driven magnetically?

In this note we investigate the possibility of magnetic driving of loop transients. The action of local magnetic forces to balance gravity in a coasting loop and to confine the loop has been proposed by Mouschovias and Poland (1977). In this paper we use similar configurations but deal with the global field structure and present models which show both the initial phase of large acceleration and the later phase of almost constant velocity. We use very simple one-dimensional models consisting of a ring current which is subjected to gravitational attraction. The velocity curves calculated for these models are in good agreement with the observations. Therefore we conclude that if such ring currents can be produced fast enough in the solar corona, they are capable of driving the loop transients observed in the ATM white light coronagraph.On leave from Max-Planck Institut für Physik und Astrophysik, Föhringer Ring 6, 8 München 40, F.R.G.The National Center for Atmospheric Research is sponsored by the National Science Foundation.     

A study on the bio-hydro mechanical effects of the tree roots on the Agaclı coal reclaimed – forested land

The research area that is in the north of Istanbul (Turkey) and it is a land of open pit coal mining residuals reclaimed and turned to forest in 1988–1989. The materials that are open pit mine spoils are formed by sandy loam, sandy clay loam, heavy loam and clay (noncalcareous Pliocene I sediments). Pseudoacacia (Robinia pseudoacacia), Maritima Pine (Pinus pinaster) and Stone Pine (Pinus pinea) are planted on these materials. The aims of this research were to determine the strength of the material provided by tree roots and evaluate the performance of the forestation practices at lands especially where open pit coal mining spoil (residual) materials piled up. The research has been performed at two stages. The first one was hydro-mechanical effect concerned about material moisture depletion as a result of transpiration and the second one was bio-mechanical effects due to strength parameters of the roots and their growth pattern within the material. All results were evaluated in relation to tensile strength and displacement curves due to pre and post failure behaviors of materials and root systems. The results showed the increase of the displacement of the material was the significant indicator of the bio-mechanics tensile strength of the material provided by the tree roots. The fast growing type of tree roots have stabilized the material up to a depth for 80–100 cm by covering the coal residual materials within 12 years.     

Convective energy transport in stellar atmospheres

The motion of convective cells in an environment which changes rapidly with depth is examined. In such an environment a cell may move through regions with different levels of ionization and with associated differences in heat capacity. The energy equation is cast in a manner which is independent of the history of these cells. The convective flux at a given level of the atmosphere is written as an average over an ensemble of cells originating at a range of other levels. A procedure for correcting the temperature gradient for these non-local effects is described and results for a model solar atmosphere are given. The principal results are: (1) The rms velocity varies smoothly and is non-zero well into the photosphere (e.g.,v _rsm=1.4 km/sec at =0.2); (2) Convective overshoot reduces the radiative flux to 60% and 90% of the total at =2.5 and 0.2 respectively; and (3) The interior adiabat of the convective envelope is less sensitive to the assumed value of the average cell size than in the usual treatment of convection.Supported in part by the National Science Foundation [GP-9433, GP-9114], the Office of Naval Research [Nonr-220(47)], and Air Force Grant AG-AFOSR-171-67.