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711.
M. T. Krupenin A. V. Maslov I. D. Tsybulenko R. A. Nafikov V. G. Petrishcheva 《Lithology and Mineral Resources》2000,35(3):267-277
A property of swelling on heating to yield firm lightweight granules has first been revealed for lowcarbonaceous shales (LCS)
from the Riphean stratotype in the Bashkirian Megaanticlinorium, Southern Urals. These granules possess all technological
properties of “keramzite” or claydite (an artificial, expanded clayey material) and can successfully substitute this material.
Moreover, the procedure of their manufacture, analogous to the manufacture of “shungizite” (an artificial carbonaceous-clayey
material) from Lower Proterozoic clayey rocks of Karelia, is more economical than that for keramzit. Productive beds of the
homogeneous LCS make up extended bodies tens of meters thick. At the present time, they can be used as cover rocks during
the exploitation of the Bakal siderite deposits. The LCS represent fine-grained quartz-chlorite-sericite aggregates (with
variable relationships between the major components), bearing fine-dispersed shungite in amounts of 0.5–1.0%. High-quality
raw material of this kind is characterized by a fine-dispersed admixture of a mixed-layer clayey material bearing montmorillonite
and vermiculite. Geological, lithological, mineralogical, and chemical prognostic criteria have been developed for the shungizite
raw material. It has been concluded that this construction material, new for the Urals, is promising for industrial use 相似文献
712.
713.
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715.
J. I. S. Zonneveld 《International Journal of Earth Sciences》1955,43(2):425-426
Ohne Zusammenfassung 相似文献
716.
717.
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. 相似文献
718.
Branislav S. Djurdjev 《GeoJournal》1995,35(4):409-413
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. 相似文献
719.
Zusammenfassung Die massenspektrometrische Analyse kleinster Gasmengen von H2, O2, CO, CO2, CH4 und H2O ist infolge der Beeinflussung durch das Meßsystem mit beachtlichen Schwierigkeiten verbunden. Die Beeinflussung erfolgt einerseits durch Reaktionen der Gase mit heißen Metalloberflächen und andererseits durch im System vorhandene Glasoberflächen. Bei einer entprechenden apparativen Anordnung, Erhitzen der Proben und Trennung der Gase durch Kühlfallen, können Gasmengen in und auf Mineralen bis zu 0,005 mm3/NDT quantitativ bestimmt werden. Die Apparatur ist durch thermische Zersetzung von Muskovit-, Calcitkristallen usw. geeicht. Die Anwendung dieser Methode auf das Gebiet der Chemie und Mineralogie sowie die Grenzen und Möglichkeiten einer quantitativen Analyse von Restgasen wird gezeigt.
Mit 5 Abbildungen 相似文献
Mass-spectrometric analysis of gases of the system C-H-O in minerals
Summary The analysis by mass-spectrometer of smallest amounts of gases H2, O2, CO, CO2, CH4 and H2O, respectively, meets with considerable difficulties, because of the influence by the measuring system. The influence is caused by interactions of the gases with hot metal surfaces on one hand, and glass surfaces on the other hand. By a suitable arrangement of apparatus and procedures, such as heating the samples and separating the gases by cooling traps, the gas amounts in and on minerals can be quantitatively determined up to 0.005 mm3/SPT. The apparatus is calibrated by thermal dissociation of crystals like muscovite, calcite etc. The application of this method in chemistry and mineralogy is treated as well as the limits and the possibility of the quantitative analysis of residual gas.
Mit 5 Abbildungen 相似文献
720.
The Hodson mining district is in the westernmost foothills of the Sierra Nevada in California, about 17 km west of the town of Angels Camp. This district is part of the West Gold Belt, which lies about 12–16 km west of, and generally parallel to, the better known Mother Lode Gold Belt in central California. The district produced several million dollars worth of Au between about 1890 and 1940. 相似文献