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Open access

Damjan Klobčar, Maja Lindič and Matija Bušić

Abstract

This paper presents an overview of additive manu­facturing technologies for production of metal parts. A special attention is set to wire arc additive manufac­turing (WAAM) technologies, which include MIG/MAG welding, TIG welding and plasma welding. Their advan­tages compared to laser or electron beam technologies are lower investment and operational costs. However, these processes have lower dimensional accuracy of produced structures. Owing to special features and higher productivity, the WAAM technologies are more suitable for production of bigger parts. WAAM technology has been used together with welding robot and a cold metal transfer (CMT) power source. Thin walls have been produced using G3Si1 welding wire. The microstructure and hardness of produced structures were analysed and measured. A research was done to deter­mine the optimal welding parameters for production of thin walls with smooth surface. A SprutCAM software was used to make a code for 3D printing of sample part.

Open access

Alexandra Herg and Kurt Stüwe

Abstract

In order to constrain tectonic models for the nature of the Eoalpine high pressure belt at the eastern end of the Alps, we investigate the formation pressure of metamorphic rocks along a profile between the Koralpe and the well-known UHP rocks of the southern Pohorje mountains. Rocks from three different regions are considered: (i) the rocks of the southernmost Koralpe to the north, (ii) the rocks of the Plankogel Unit between the Plankogel detachment and the Drava valley and (iii) the rocks between the Possruck range and the southern Pohorje mountains. In the Koralpe, pelitic rocks record a formation pressure around 15 – 18 kbar, as reported in the literature. For the Plankogel Unit, we derive pressures between 7.1 ± 1.95 kbar and 11.5 ± 3.42 kbar at 650 °C and recognize only a single Eoalpine metamorphic event. For the high grade rocks of the Pohorje mountains, we derive peak metamorphic pressures (explored with the garnet-muscovite-kyanite-quartz assemblage) that rise from 16.2 ± 3.45 kbar (at 700°C) in the north, to 23.9 ± 2.49 kbar (at 700 °C) in the south. There, we also recognize a later lower pressure event that is derived from pressure calculations with the full equilibrium assemblage. This lower pressure event yields similar conditions around 10 ± 2 kbar at 650 °C for the entire north-south transect within the Pohorje mountains. Peak metamorphic conditions in the Koralpe and Pohorje regions are matched by a continuous field gradient of about 1.3 kbar per 10 kilometers distance corresponding to a depth increase of about 0.5 km per kilometers distance assuming lithostatic conditions. We suggest that this supports that the two units may be interpreted together in terms of a 45° dipping subducting plate. Above this subducting plate, it is inferred that a slab was extracted that was located between the Plankogel Unit and the high pressure rocks, causing a first exhumation stage that is associated with buoyant upwards tilting of the subducted slab to mid crustal levels. Within this model, the Plankogel Unit was located in the hanging wall of the extracted slab and the Plankogel detachment forms the suture of the extracted slab. Exhumation from mid crustal levels to the surface during a 2nd stage occurred due to erosion and normal faulting. This normal faulting is responsible for some 10 km of upward displacement of the Pohorje mountains relative to the Koralpe and ultimately for the current distribution of lithologies on a map scale.

Open access

Pitsanupong Kanjanapayont, Peekamon Ponmanee, Bernhard Grasemann, Urs Klötzli and Prayath Nantasin

Abstract

The NW–trending Three Pagodas shear zone exposes a high–grade metamorphic complex named Thabsila gneiss in the Kanchanaburi region, western Thailand. The quartz mylonites within this strike–slip zone were selected for strain analysis. 2–dimensional strain analysis indicates that the averaged strain ratio (Rs) for the lower greenschist facies increment of XZ– plane is Rs = 1.60–1.97 by using the Fry’s method. Kinematic vorticity analysis of the quartz mylonites in the shear zone showed that the mean kinematic vorticity number of this increment is Wk = 0.75–0.99 with an average at 0.90 ±0.07. The results implied that the quartz mylonites within the Three Pagodas shear zone have a dominant simple shear component of about 72% with a small pure shear component. A sinistral shear sense is indicated by kinematic indicators from macro– to micro–scale. We conclude that the Three Pagodas shear zone deformed in the process of sinstral shear–dominated transpression, which is similar to the Mae Ping shear zone in the north.

Open access

Anna Sieczka, Filip Bujakowski and Eugeniusz Koda

Abstract

The present paper discusses studies related to the preparation of a hydrogeological model of groundwater flow and nitrate transport in an area where a precision farming system is applied. Components of water balance were determined using the UnSat Suite Plus software (HELP model), while the average infiltration rate calculated for the study area equalled 20 per cent. The Visual MODFLOW software was used for the purpose of modelling in the saturated zone. Hydrogeological parameters of the model layers, inclusive of hydraulic conductivity, were defined on the basis of results of column tests that were carried out under laboratory conditions (column experiment). Related to the dose of mineral nitrogen used in precision fertilisation (80 kg N/ha), scenarios of the spread of nitrates in the soil-water environment were worked out. The absolute residual mean error calculated for nitrate concentrations obtained from laboratory and modelling studies equalled 0.188 mg/L, the standard error of the estimate equalling 0.116 mg/L. Results obtained were shown graphically in the form of hydroisohypse maps and nitrate isolines. Conclusions were drawn regarding the possibility of using numerical modelling techniques in predicting transport and fate of nitrates from fertilisers applied in precision agriculture systems.

Open access

Andrzej Ślączka, Marta Bąk, Clemens Pfersmann, Veronika Koukal, Michael Wagreich, Szymon Kowalik and Martin Maslo

Abstract

Two sections of the klippen zones in the Wienerwald area have been investigated for their stratigraphy: (1) The Gern section of the Main Klippen Zone, a part of the Gresten Klippen Zone, and (2) the St. Veit Klippen Zone in the Lainz Tunnel and the neighboring outcrops in western Vienna. New biostratigraphic data are based on radiolaria from siliceous intervals and a few findings of calcareous nannofossils from marlstones. In the Gresten Klippen Zone, radiolarian assemblages from limestones of the Gern locality indicate a middle Oxfordian to early Kimmeridgian age of the Scheibbsbach Formation.

Radiolarian and nannofossil data from the St. Veit Klippen Zone in the Lainz railway tunnel locality, as well as correlated outcrops from the Lainzer Tiergarten and the Gemeindeberg in the southwest of Vienna, indicate the presence of mainly Bajocian to lower Oxfordian red radiolarites and cherts (Rotenberg Formation). Siliceous, grey limestones and cherts of the Fasselgraben Formation range from the upper Oxfordian–Kimmeridgian to the Valanginian–Barremian.

The Main Klippen Zone was derived from the European margin to the north, and this zone is regarded as a Helvetic paleogeographic unit. The St. Veit Klippen Zone in the Lainz Tunnel section contains no ophiolitic material and shows a tectonic contact with the surrounding Rhenodanubian nappe system, which indicates no primary sedimentary contact of the St. Veit Klippen Zone with the Flysch units, as well as demonstrating the presence of two structurally separated Alpine tectonic units. Thus, a direct correlation with the Ybbsitz Zone is not supported, and an original paleogeographic position in the transition from the Penninic Ocean to the Austroalpine continental fragment is proposed.

Open access

Zbigniew Kordalski and Andrzej Sadurski

Abstract

During the last nine years, the 133 main groundwater reservoirs in Poland (MGR) have been documented; these were published last year. Some of these are situated in the coastal zone of the southern Baltic Sea. MGR numbers 111 and 112 are in the Gdańsk area and are discussed in the present paper. The study area is situated on the border region of the moraine plateau of the Cashubian Lakeland, the western part of the Vistula River delta plain and the Bay of Gdańsk. The area of the main groundwater reservoir in no. 112 is developed in Quaternary strata and referred to as Żuławy Gdańskie; it comprises predominantly the city of Gdańsk and slightly exceeds 100 km2. There is also a Cretaceous aquifer, rich in groundwater resources, which is named MGR no. 111, beneath the Quaternary reservoir mentioned above. The area studied and modelled totalled 364 km2, on account of the hydraulic connection between these aquifers. Methods of hydrogeological research, groundwater flow simulations, resources calculation are outlined in the present paper.

Open access

Ryszard Hoc, Andrzej Sadurski and Zenon Wiśniowski

Abstract

During the construction of mathematical models for mapping hydrogeological conditions it is necessary to apply simplifications, both in the geological structure and in hydrogeological parameters used. The present note discusses problems surrounding the mapping of glaciotectonic disturbances that occur in the northern part of Wolin Island (northwest Poland). For this part of the island, a direct outflow of groundwater towards the Baltic Sea basin has been determined on the basis of geophysical survey results. An important feature in the hydrogeological conditions here is the isolation of groundwater from both the Baltic Sea and Szczecin Lagoon by clay with a Cretaceous xenolith. Such a geological structure explains the presence of perched water at considerable heights in zones close to the cliffs, without any significant hydraulic connection with surrounding reservoirs. Hydrogeological conditions of Wolin Island have been modelled using the Visual MODFLOW package v.4.2. In the vertical section, these conditions can be simplified to one aquifer (Pleistocene-Holocene), in which two aquifers can be distinguished. In a large part of the island, these remain in mutual hydraulic contact: layer I – upper, with an unconfined aquifer, and layer II – lower, with a confined aquifer, locally an unconfined one. The schematisation of hydrogeological conditions adopted here has allowed to reproduce present groundwater dynamics in the study area.

Open access

Marta Dendys, Andrzej Szczepański and Barbara Tomaszewska

Abstract

The Miechów Trough and the central part of the Carpathian Foredeep in southern Poland have a highly complex geological structure and numerous fault zones. These features play a significant role in hydrogeological conditions of the area. In this area drinking water, medicinal groundwater or thermal groundwater occur, so recognition of their circulations is basic for reasonable groundwater management. In this note, a hydrogeological conceptual model, created for the purpose of regional scale mathematical modelling, is presented. This conceptual model illustrates the geology of the hydrogeological system modelled, as well as hydrogeological conditions and characteristics of groundwater circulation, as determined by tectonics. Typical of the research area is the wide diversity of geological and hydrogeological conditions. The Busko-Zdrój area, a region with a long history of exploitation of medicinal groundwater, presents the best example.

Open access

Ohanyiri C. Chiemezie and Omotowo B. Aminat

Abstract

Geochemical studies of claystone deposits from the Patti Formation in the southern Bida Basin, north-Cen­tral Nigeria, were carried out on representative sam­ples to determine the basin’s depositional conditions, provenance and tectonic setting. The localities within the study area included Gegu, Ahoko, Ahoko-Etigi, Omu and Idu. Semi-quantitative phase analysis using the Rietveld method and X-ray powder diffraction data revealed that the claystone samples had prominent kaolinite with other constituents such as quartz, illite-mus­covite, K-feldspar, pyrite, marcasite, anatase, rutile and gorceixite. Enrichment of Al2O3, Ba, Th, Sr, Cr and La suggests that these elements are primarily controlled by the domi­nant clay minerals. Geochemical parameters such as U, U/Th, Ni/Co, V/Cr and Cu/Zn ratios strongly implied that these claystones were deposited in an oxidising environment. Provenance deducing ratios for felsic, mafic and basic igne­ous rocks were compared. Al2O3/TiO2 ratio suggested intermediate to felsic rocks as the probable source rocks for the claystone samples; however, Y/Ni, Cr/V, La/Sc and Th/Sc ratios suggested a felsic progenitor. The tectonic discrimination diagram showed that the samples’ plot was within the region specified for passive margin-type tectonic setting.