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Abstract

This paper presents one of the environmental problems occurring during underground mine closures: according to the underground coal mine closure programme in Germany, the behaviour of the land surface caused by flooding of the entire planned mining area – the Ruhr District – had to be addressed. It was highlighted that water drainage would need to be continuous; otherwise, water levels would rise again in the mining areas, resulting in flooding of currently highly urbanised zones. Based on the variant analysis, it was concluded that the expected uniform ground movements caused by the planned rise in the mining water levels (comprising a part of two concepts – flooding up to the level of –500 m a.s.l. and −600 m a.s.l.), in the RAG Aktiengesellschaft mines, will not result in new mining damage to traditional buildings. The analysis included calculations of the maximum land surface uplift and the most unfavourable deformation factor values on the land surface, important from the point of view of buildings and structures: tilt T, compressive strain ε– and tensile strain ε+. The impact of flooding on potential, discontinuous land surface deformation was also analysed.
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Authors and Affiliations

Krzysztof Tajduś
1
ORCID: ORCID
Anton Sroka
2
ORCID: ORCID
Mateusz Dudek
2
ORCID: ORCID
Rafał Misa
2
ORCID: ORCID
Stefan Hager
3
ORCID: ORCID
Janusz Rusek
1
ORCID: ORCID

  1. AGH University of Krakow, Al. A. Mickiewicza 30, 30-059 Kraków, Poland
  2. Strata Mechanics Research Institutes of Polish Academy of Science, 27 Reymonta Str., 30-059 Kraków, Poland
  3. R AG Aktiengesellschaft, Essen, Germany
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Abstract

This article consists of two parts. The first part summarizes using informal language Wolniewicz’s understanding of the idea of God which he expressed in the language of formal logic. It demonstrates that Wolniewicz’s position was founded on antinaturalism, i.e. the conviction that nature is a fragment of a larger reality while man partly transcends the natural reality. The second part of the article is an attempt at capturing the intuitions behind Wolniewicz’s idea of God as an impersonal power which is not identical with Providence though. It is argued that this view is a consequence of the characteristic traits of Wolniewicz’s personality. This explanation is consistent with Wolniewicz’s understanding of human nature. In the analysis that ensues reference is made to Wolniewicz’s private correspondence.

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Authors and Affiliations

Jerzy Kopania
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Abstract

In marine seismic wide−angle profiling the recorded wave field is dominated by waves propagating in the water. These strong direct and multiple water waves are generally treated as noise, and considerable processing efforts are employed in order minimize their influences. In this paper we demonstrate how the water arrivals can be used to determine the water velocity beneath the seismic wide−angle profile acquired in the Northern Atlantic. The pattern of water multiples generated by air−guns and recorded by Ocean Bottom Seismometers (OBS) changes with ocean depth and allows determination of 2D model of velocity. Along the profile, the water velocity is found to change from about 1450 to approximately 1490 m/s. In the uppermost 400 m the velocities are in the range of 1455–1475 m/s, corresponding to the oceanic thermocline. In the deep ocean there is a velocity decrease with depth, and a minimum velocity of about 1450 m/s is reached at about 1.5 km depth. Be − low that, the velocity increases to about 1495 m/s at approximately 2.5 km depth. Our model compares well with estimates from CTD (Conductivity, Temperature, Depth) data collected nearby, suggesting that the modelling of water multiples from OBS data might be − come an important oceanographic tool.
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Authors and Affiliations

Marek Grad
Rolf Mjelde
Wojciech Czuba
Aleksander Guterch
Johannes Schweitzer
Ipy Project Group
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Abstract

Phytoplankton composition plays a major role in biogeochemical cycles of the ocean. The intensity of carbon fixation and export is strongly dependent on the phytoplankton community. Yet, the contribution of different types of phytoplankton to the total production on various communities is still poorly understood in the Indian Ocean sector of Southern Ocean (SO). Therefore the variability of chlorophyll- A (Chl-a) and diatoms in the frontal ecosystems of the Indian sector of SO have been investigated along with the sea surface temperature (SST), sea surface wind (SSW), photosynthetically active radiation (PAR), and nutrients datasets for the period of 1998-2012. Combined analysis of in-situ, model and satellite observations indicate that the variability of Chl- A and diatoms were primarily influenced by light and wind. The Chl- A was higher at the sub-Antarctic front (SAF) followed by the sub-tropical front (STF) and the polar front (PF). The diatom concentration was higher at the SAF followed by the PF and STF. Maximum concentration of Chl- A and diatoms commonly observed at the SAF region are probably due to the moderate PAR, SST and wind. Dominance of diatoms at the PF may be attributed to their adaptability for low light conditions. The results from this study in the frontal ecosystems would help to understand the biogeochemical cycle of the Indian sector of the SO.
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Authors and Affiliations

Mishra Rajani Kanta
Jena Babula
Narayana Pillai Anilkumar
Naik Ravidas Krishna
Parli Venkateswaran Bhaskar
Melena A. Soares

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