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61.
This article aims to explain and demonstrate the origin and development of a subsidence basin caused by coal mining as well as to point out important aspects of this phenomenon in engineering geology. Engineering geology needs to deal with a number of issues related to the origin and development of subsidence basins in areas affected by deep coal mining. An interesting case study from the Upper-Silesian Basin in the northeast of the Czech Republic near the Polish border is presented in this paper. There is a clear time chronological succession in the ground surface changes manifested by a ground subsidence gradation, both in their absolute values as well as in their spatial distribution. The phenomenon is documented by aerial photo time series, which optimally depict the origin and development of the subsidence. In the study area, there are changes in the landscape elements and it is essential to be considered in future land use plans. The marginal conditions of the Quaternary geological structure and hydrogeological conditions are responsible for an unconfined aquifer which manifests there as a water body in an undrained depression in the course of the ground subsidence.  相似文献   
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Four sediment traps of radically different design were deployed in the Santa Barbara Basin for approximately 45 days. The measured fluxes ranged from 370 to 774 g m?2 yr?1 for the different designs. These values lie within flux measurements previously determined for the basin. Compared to the 25-year record (920 g m?2 yr?1), however, all fluxes determined in this experiment are somewhat low. Because this experiment was conducted during a general period of high storm activity and runoff, measurement of greater than average flux was expected. It is probable that the higher flux recorded by the sediments results from a significant input of detritus into the basin by near bottom transport.The chemical composition of trapped material was nearly identical in all four trap designs. The deep cone design, however, had a significantly lower Mn content. Since this trap was the only one in which reducing conditions were produced in the sample container, reduction and mobilization of manganese after collection is believed to have occurred.In spite of the very different designs tested, the factor of two agreement in flux determination and the compositional similarity of the material collected is encouraging for future attempts to directly measure the flux of particulates in the ocean.  相似文献   
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Summary The results of two different methods of the determination of the non-linearity of the gravimeter scale are compared; the economy is discussed as well.  相似文献   
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Summary Relations for the direct transformation of the Cartesian coordinate system into a system of geodetic coordinates.
u ¶rt;u , , z ¶rt;uu , , h.
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Summary The position of the Sun with respect to the gravity centre of the Solar System for the beginning of every year of a 3100 — year time series was determined and the harmonic analysis of the parameters of the Sun's motion about the gravity centre was carried out.
unu u u ¶rt; ¶rt;¶rt; u ¶rt; ¶rt;u 3100 u c¶rt;uu u n ¶rt;uu u.
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Summary The boundary condition for the gravity disturbing potential was derived upto the second-order terms and the influence of the second-order terms was investigated.Dedicated to 90th Birthday of Professor Frantiek Fiala  相似文献   
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