Eine Differenzmethode zur Erhöhung der Meßgenauigkeit und Erweiterung des Meßbereiches normaler Drehkompensatoren

Zusammenfassung Eine Differenzmethode zur Erhöhung den Genauigkeit der Messung von optischen Gangunterschieden durch Drehkompensatoren und Erweiterung von deren Mcßbereich wind beschrieben und durch Beispiele geprüft und erläutert.Der Vorteil dieses Verfahrens liegt in der erreichbaren Genauigkeit der Bestimmung kleiner und großer , die meist haher liegt als die der direkten Ermittelung durch Kompensation auf . = 0.Bei kleinen und großen , kann durch Messung einer Summe von Gangunterschieden oder eines Restgangunterschiedes anstatt des im Meßpräparat vorliegenden die Messung stets in den besten Meßbereich des jeweils vorliegenden Kompensators gerückt werden. Darüberhinaus sind höhere, durch Kompensatoren mit kleinerem Meßbereich ebenso genau bzw. nosh genauer bestimmbar. Es muß nun durch einen Quarzkeil oder einen underen Kompensator die ungefähre Lage der Kompensationsstelle auf = 0 ermittelt werden.Unter Verwendung monoehromatischen Lichtes können auch in der Additionsstellung von Meßpraparat und Kompensator ebensogut und genau bestimmt werden wie in der bisher traditionell bevorzugten Subtraktionsstellung.     

Beobachtungen an der Küste von Suriname

Ohne Zusammenfassung     

Occurrence of hypogenic caves in a karst region: Examples from central Italy

The caves of the Umbria and Marche regions in central Italy are made up of three-dimensional maze systems that display different general morphologies due to the various geological and structural contexts. At the same time, the internal morphologies of the passages, galleries, and shafts present some similarity, with solutional galleries characterized by cupolas and blind pits, anastamotic passages, roof pendants, and phreatic passages situated at different levels. Some of these caves are still active, as is the case for Frassassi Gorge, Parrano Gorge, and Acquasanta Terme, with galleries that reach the phreatic zone, where there is a rising of highly mineralized water, rich in hydrosulfydric acid, and with erosion of limestone walls and the formation of gypsum. Elsewhere there are fossil caves, such as Monte Cucco and Pozzi della Piana, where large speleothems of gypsum are present 500 m or more above the regional water table. In all of these important karst systems it is possible to recognize basal input points through fracture and intergranular porosity networks at the base of the oxidizing zone in the core of the anticline, where mineralized water rises up from the Triassic evaporitic layers in small hydrogeological circuits. Different underground morphologies can derive from the presence of a water table related to an external stream or from the confined setting of the carbonate rocks, underlying low permeable sedimentary cover, where artesian conditions can occur.     

Border effects on household dissolution in the Banat Region,Yugoslavia

Abstarct The article recognizes two border effects on average size of households: the past and the present one.Both the incidence and the long-standing tradition of the multifamily and multigenerational households in the past time have been attributed to the influence of Turkish and Austrian state regulations in the period when the area was a part of the Military Border.An attempt is made to estimate the share of vital and spatial mobility factors. In the contemporary process of household dissolution the impact of vital mobility decreases and the impact of spatial mobility increases going from the center towards the periphery.An earlier version of this paper was presented at the Regional Conference of the International Geographical Union, held in Prague in 1994.     

Über Eckfluren und andere Probleme der Talbildung

Ohne Zusammenfassung     

Isotope composition of Medieval lead glasses reflecting early silver production in Central Europe

The lead isotope composition of 32 lead glasses excavated from strata of the twelfth to early fifteenth century in six countries of NW Europe made the predominance of the Harz Mountains in this period of the Medieval European lead and silver production highly probable. Post-Variscan vein type galena, Devonian syngenetic hydrothermal ore (Rammelsberg) and blended ore from both deposits in the Harz were used. Our evaluation of 200 mining sites in Germany, Britain and Ireland also demonstrated that minor lead sources for lead glass were located in Bavaria/Bohemia and England. Lead ores from the Rhenohercynian orogenic belt in Germany are derived from rock sources close to the upper continental crust composition in ²³⁸U/²⁰⁴Pb of about 10 and Th/U of about 4. The ores in Central England originated from rocks with ²³⁸U/²⁰⁴Pb of about 11. Received: 24 September 1996 / Accepted: 17 January 1997