This study describes the luminescence characteristics of quartz of Upper Pleistocene loess of the Middle Rhine area. The loess/palaeosol sequence of the Schwalbenberg near Remagen comprises a multitude of interstadial soils and soil sediments that have been dedicated to the Marine Isotope Stage 3 (MIS 3). These weak calcaric cambisols and their derivates are underlain by loess and soil sediments of MIS 4 to MIS 5 and covered by loess sediments and intercalated gelic gleysols of MIS 2. We applied luminescence dating of quartz and feldspar of drill core samples and observed an age discrepancy within both data sets. The quartz ages were clearly younger than the feldspar ages, because of thermally unstable signal components of the quartz luminescence signal. Therefore, we regarded the quartz samples of the lower parts of the drill core as unsuitable for luminescence dating. This underestimation did not affect the quartz samples of the upper part of the drill core which was indicated by age control that was provided by the Eltville tephra layer. Geochemical analysis based on X-ray fluorescence showed that the sediments in the upper part and the lower part of the drill core have different geogenic finger prints most likely due to changing source areas of dust and sediment allocation. We assumed that these different facies types were the reason for the luminescence behavior of the quartz samples.
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Reducing mining costs has become such an important factor in the German coal industry that operators are forced to work only those areas where production costs can be kept low. These areas will normally be located close to the mine shafts because they are easily accessible. Even the shaft pillar is now being considered as part of the winning zone. Before working coal in shaft pillar zones it is essential to assess the impact this will have on the shaft lining. There is a huge difference between sliding and strata-anchored shaft systems. However, if the overburden comprises lightweight soil both types of shaft will have a tendency to protrude from the surrounding ground. The following paper presents the geomechanical reasons underlying this reaction and the methods used for predicting and measuring it.
PL
Zmniejszenie kosztów wydobycia staje się tak ważnym czynnikiem w niemieckim przemyśle węglowym, że operatorzy są zmuszeni do pracy tylko w tych miejscach, gdzie koszty produkcji mogą zostać utrzymane na niskim poziomie. Tereny te zwykle znajdują się blisko szybów kopalnianych, ponieważ są z łatwością dostępne. Nawet filar ochronny szybu jest obecnie uważany za część strefy dobrego uzysku. Przed wydobyciem węgla ze stref filaru ochronnego szybu konieczne jest ocenienie, czy będzie miało to wpływ na obudowę szybu. Różnica między systemami obudów przesuwnymi i kotwionymi w pokładach jest ogromna. Jednak jeżeli nadkład obejmuje gleby lekkie, oba rodzaje szybów będą miały skłonność do wystawania z pobliskiego gruntu. Opracowanie przedstawia geomechaniczne powody zachodzenia tej reakcji i metody stosowane dla jej przewidywania i mierzenia.
We describe we role of neutron and synchrotron radiation (SR) diffraction methods in the investigations of the crystal and magnetic structure of polycrystalline materials. Several examples of neutron and synchrotron radiation diffraction studies are presented. We discuss the structural properties of the following materials: cellular random system with magnetic spin-glass properties and manganite system with long range magnetic ordering at low temperatures.
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