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EN
The article presents the results of research from the Mokrzeszów site in the Sudetic Foreland. Lithopetrographic and sedimentological analyses of sediments from the Middle Polish Glaciations (Early Saalian, Odranian, MIS6) in this area indicate the overrepresentation (90–95%) of large Scandinavian erratics. The deposits, representing a repetitive sequence of Gp-Gms-Sp-Sh/Sr(Dmm) lithofacies, accumulated during at least two episodes of glacial outburst floods and six sedimentary cycles. High-energy flows are estimated for the Gms and Gp facies at about 5 m∙s−1 and low-energy flows indicate 0.8 m∙s−1 for the Sp/Sh/Sr facies, to the lack of flow (Fm). The sedimentary sequences confirm the existence of a fan, which may have originated as a subaqueous steep coarse-grained fan in glacial-flow-lake-outburst floods that formed between the ice sheet front and the morphotectonic edge of the Sudetic Marginal Fault line and within the Roztoka-Mokrzeszów Graben, or as an aerial, piedmont fan on the Sudetic Marginal Fault edge. The sediments show discontinuous deformations – gently sloping faults and fractures from glacioisostatic stresses. The fault activity is probably related to the reactivation of the faults due to ice loading during or after the older Saalian glaciation.
PL
Badania deformacji górotworu w rejonie zabytkowej Kaplicy św. Kingi Kopalni Soli „Bochnia” z zastosowaniem elektromagnetycznej sondy ekstensometrycznej dają nową jakość w analizie charakterystyki tego procesu. Pomiary przemieszczeń reperów stanowiących punkty osnowy kopalnianej z zastosowaniem klasycznych przyrządów i instrumentów geodezyjnych pozwalają jedynie na określenie geometrycznych zmian konturu wyrobisk, często wysoko dokładnych. Na bazie wyników klasycznych pomiarów mierniczych niemożliwe jest określanie sposobu propagacji deformacji wewnątrz górotworu. Wykonane badania z zastosowaniem sond ekstensometrycznych umożliwiły opracowanie charakterystyki odkształceń calizny górotworu solnego w KS Bochnia oraz powiązanie tych wyników z wieloletnimi pomiarami geodezyjnymi. Jak dotąd nie ma opracowań, które w wiarygodny sposób przedstawiają sposób rozchodzenia się deformacji w caliźnie górotworu otaczającej wyrobiska. Jak się podejrzewa, jest on poddany dodatkowo naciskom wciąż aktywnych tektonicznie Karpat sąsiadujących ze złożem. Poza aspektem naukowym przybliżenia opisu zjawisk zachodzących wokół wyrobisk podziemnych w KS Bochnia, istotny jest również aspekt praktyczny, który dotyczy sposobu prowadzenia ewentualnych zabezpieczeń zabytkowych wyrobisk.
EN
Measurements of rock mass deformation with application of electromagnetic extensometer in the Saint Kinga Chapel of The Bochnia Salt Mine provided a new quality of in studies of the process’s performance. Measurements of displacements of control points which are consisted of in the mine’s geodetic network with the use of classical device devices and instruments enable to determine of changes of cavities’ contours only, however with high accuracy. The carried out measurements with the use of electromagnetic extensometer supported elaboration of deformation of undisturbed rock mass surrounding the cavity in The Bochnia Salt Mine that could be combined the results with long standing geodetic observations. As far there is no studies which present reliably propagation of deformation within rock salt mass surrounding underground excavations. As suspected, the rock mass is subjected to additional stress of the Carpathians orogeny, neighboring the salt deposit and which is still tectonically active. Apart from the scientific aspect which brings closer the problem depicting propagation of phenomena ongoing around underground cavity in The Bochnia Salt Mine, there is a practical aspect pertaining to of eventual support methods being constructed in the historical excavations.
EN
Slow, long-term ground deformations in the Dąbrowa Basin (southern Poland) were identified based on ERS-1, ERS-2 and ENVISAT Synthetic Aperture Radar (SAR) images that were processed by means of Permanent Scatterer SAR Interferometry (PSInSAR). The Dąbrowa Basin is a region where two major factors can affect surface stability: intensive coal exploitation and neotectonic processes. In this study, in order to clarify the origin of surface deformations, the authors propose applying a newly developed algorithm of spatio-temporal PSInSAR data analysis. This analysis revealed that subsidence is a characteristic feature of the Dąbrowa Basin. A significant correlation exists between slow, long-term ground deformations and the location of the main tectonic structure of this region. The proposed spatiotemporal analysis of the PSInSAR data additionally showed some degree of correlation between mining activity and the studied deformations. This interconnection is a significant achievement of this study since the deformation values determined by means of PSInSAR were identified in earlier works solely on the basis of Dąbrowa Basin neotectonics.
EN
The presented work deals with the problem of terrain surface and rock mass deformation in the area of the Bochnia Salt Mine. The deformations are related to natural causes (mainly the tectonic stress of the Carpathian orogen) as well as anthropogenic ones related to the past mining activity conducted directly under the buildings of the town of Bochnia. The discussed characteristics of land surface deformation are important from the point of view of threats to surface features and contribute to spatial development. Particularly anomalous zones of observed subsidence basins are examined as places of second order deformation effects. The author presents a method of determinations of these anomalous areas and he discusses their origins.
PL
Przestawiona praca dotyczy problematyki deformacji powierzchni i górotworu w rejonie Kopalni Soli Bochnia. Deformacje te związane są zarówno z przyczynami naturalnymi (głównie nacisk tektoniczny orogenu karpackiego), jak i antropogenicznymi związanymi z minioną aktywnością górniczą prowadzoną bezpośrednio pod zabudową miejską Bochni. Omówione charakterystyki deformacji powierzchni terenu są istotne z punktu widzenia zagrożeń dla obiektów powierzchni oraz są elementem planowania przestrzennego. Szczególnie przeanalizowane zostały strefy anomalne niecki obniżeniowej jako efekty drugiego rzędu deformacji. Autor przedstawił sposób ich wyznaczania oraz omówił genezę ich powstania.
EN
Seismic events in the area of Poland are related mostly to copper and coal mining, and they are regarded as the most dangerous natural hazard. Although development of geomechanical modelling as the development of geophysical methods determining seismic hazard are evident, low predictability of the time-effect relationship still remains. Geomechanical models as geophysical data analysis highlight the interaction between parts of rock mass or allow to reconstruct the way of rock mass destruction and to understand the processes that take place in the high-energy tremors. However, the association of larger mining tremors with pre-existing geological features has been reported by many investigators; in geomechanical practice, investigations of rock mass condition concentrate on this problem in the local scale. Therefore, the problem of relations between high-energy seismic events in Legnica–Głogów Copper District (LGCD) and regional scale deformations of terrain surface resulting from possible tectonic activity is discussed in this paper. The GNSS data evaluated from the observations of ASG-EUPOS (Active Geodetic Network – EUPOS) stations in the area of LGCD and in the adjacent areas is analysed in this study. Temporal variation of distances between the stations and evaluated on that base so called apparent strain was combined with the occurrence of high-energy tremors. Consequently, after the examination and analysis of occurrences of mining tremors, it is found that high-energy seismic events and periods of strain accumulation evaluated from GPS/GNSS data have temporal relations. Although the seismic events were triggered by mining, nearly all the events with energy E > 108 J occurred in the periods when the analysed stations’ positions demonstrated a decrease in the baseline length.
EN
Considerations of the relationships between the groundwater systems and neotectonics in the Roztocze region have been first undertaken by J. Malinowski in the 1970s. Until now, no research results have supported or challenged the hypothesis proposed by this author. Therefore, this paper is an attempt to present the results of a detailed analysis of the relationships between the distribution of springs characterised by the highest discharge rates and neotectonics. The study area covered the Roztocze part of the Biała Łada catchment, which has been subjected to detailed hydrogeological and hydrological investigations since the 1960s. The study was based on spatial data concerning the distribution of springs and information about the discharge rates of the largest springs. The data were juxtaposed with the relatively active tectonic zones distinguished in the catchment based on the relative tectonic activity index (Iat). The index was calculated using ArcGIS software, based on DEM, and with the use of the ArcNEO tool. The investigations indicated that springs with the highest discharge rates are located in the intersection zone of the main Biała Łada dislocation with accompanying faults. Additionally, the springs are located in the mouth sections of dry, asymmetric valleys and at the foot of their steep slopes following isostatically elevated hanging walls. The results support the hypothesis put forward by J. Malinowski (1993), who suggested that the distribution of springs with the highest discharge rates is determined by tectonics of the rock massif, in particular the distribution of the main dislocations and the accompanying subordinate discontinuous tectonic structures.
EN
In areas experiencing low deformation rates, landscapes provide limited evidence of ongoing tectonic activity, being either masked or altered by exogenic processes. Accordingly, the identification of fault activity and near surface deformation is commonly accomplished by multidisciplinary research combining geological, geophysical and geomorphic methods. In this study, Quaternary fault activity in the SW Pannonian Basin is investigated in the region of Bilogora, NE Croatia. The study area is positioned along the SW margin of the Drava Depression that was uplifted during the Pliocene and Quaternary within the Drava Depression Boundary Fault Zone. In this fault zone six GPR profiles were recorded. Reflection patterns, radar facies and truncations determined fault activity and near-surface deformation at four locations with vertical displacements of ≤1 m. At two sites, profiles did not show truncation of the shallowest reflections, however, an elevation difference of ca. 10 m between two palaeostream channels along one of the profiles suggests Quaternary uplift accommodated by a mapped fault. Considering the importance of the seismogenic potential of active faults and their correlation with the seismicity of Bilogora, this research will be followed by additional studies of near-surface strata deformation and palaeoseismological fault properties.
EN
The South Wagad Fault (SWF) is an E–W trending fault that delimits the Wagad uplift comprising Mesozoic rocks in its northern upthrown block and Neogene–Quaternary sediments in the southern downthrown block. Detailed GPR investigations were carried out at seven sites selected after field studies. All profiles clearly showed the lithological contrast across the fault. The sharp amplitude contrast of the radar waves along a vertical to sub-vertical line is interpreted as the near surface trace of the SWF. As the Quaternary sediments are not displaced, we infer that no large magnitude earthquake has occurred along the SWF in late Quaternary. We attribute the low magnitude of neotectonic activity along the SWF to gentle warping of the Tertiary rocks in the southern downthrown block and greater accumulation of compressive stresses along the nearby KMF with an opposite structural setting. This is consistent with the observed variable levels of ongoing seismicity in the region around the SWF.
EN
Producing accurate seismic hazard map and predicting hazardous areas is necessary for risk mitigation strategies. In this paper, a fuzzy logic inference system is utilized to estimate the earthquake potential and seismic zoning of Zagros Orogenic Belt. In addition to the interpretability, fuzzy predictors can capture both nonlinearity and chaotic behavior of data, where the number of data is limited. In this paper, earthquake pattern in the Zagros has been assessed for the intervals of 10 and 50 years using fuzzy rule-based model. The Molchan statistical procedure has been used to show that our forecasting model is reliable. The earthquake hazard maps for this area reveal some remarkable features that cannot be observed on the conventional maps. Regarding our achievements, some areas in the southern (Bandar Abbas), southwestern (Bandar Kangan) and western (Kermanshah) parts of Iran display high earthquake severity even though they are geographically far apart.
EN
The GNSS data evaluated from on observation of ASG EUPOS stations in the Sudety Mts. and in adjacent areas is analyzed by the author in the scope of disturbances in daily solutions that can be induced by tectonics stress. The daily position changes derived from GNSS data demonstrate the long or short term trends, which are affected by offsets of different nature. Author presents an analysis based on frequency of parameter – displacement vector azimuth. The aim of the analysis is to show statistical significance of observed small values of temporal displacements, which values are not normally distributed. There are “outliers” of the normal distribution of displacement azimuths, which values show a certain reproducibility, which corresponds to orientations of tectonic lines. That suggests small, short time movements along boundaries of horsts and grabens – a crustal-extension structure of the area. However derived results (values of displacements) are less than a limitation error, temporal distributions of coordinates are not random as usually data errors. So in author’s opinion the spatial-temporal evolution of horizontal displacements of ASG EUPOS stations in the Sudety Mts. and in adjacent areas are determined by expressions of underlying geological structures.
EN
The paper reviews the recent state ofstudies for karst phenomena on northern slopes of the Śnieżnik Massif, Krowiarki range and Zlote Mts in East Sudetes with particular reference to Biała Lądecka basin. Conflned spatial character of the d/ainagf basinand cave sites within allow a better understanding of landscape response to climate and tectonic proxies controlling landscape evolution at least since the end ofMiocene (Messinian). New karst passages discoveries from Niedźwiedzia Cave resulted in the recognition of several sites of allochthonous sediments deposited at different cave morphological levels up to 50 metres above Kleśnica river floor. Furthermore, a new model ofpolygenetic origin for some karst chambers in Niedźwiedzia Cave originating from karstification processes and mass-movements superimposed has been suggested. Presumably, it may be linked with neotectonic processes and/or climatic changes affecting East Sudetes during the Late Cenozoic.
EN
A combination of approaches to the study of neotectonics is discussed. As an example, an analysis is presented for part of the Podhale region, where changes in the hydrogeological regime were observed. Comments are made on the manifestation of geological processes and principles in investigations of neotectonics, due to the results of precise digital terrain modelling (DTM) and geodetic surveys. The results obtained lead the authors to the conclusion that a reliable study on the geological activity of an area evaluated from considerations of river-channel morphology requires attention to changes in spatial development as a factor controlling the intensity of the hydrological regime. In such cases, a database of complex geodata information is required. A geodetic approach is presented, based on GNSS observations that become a new standard in geomorphologic studies. The results of GNSS observations provide quantitative estimates of displacements in the study area and allow assessment of their kinematics.
EN
Finding productive boreholes in the Karoo fractured aquifers has never been an easy task. Fractured Karoo aquifers in the neotectonic zones in the Eastern Cape Province can be targeted for groundwater exploration. The Polile Tshisa hot spring is located in a seismo-tectonic region beset by neotectonics. Hot springs are indicative of circulation of groundwater at great depths along fault zones, and accordingly of neotectonics. The characterisation of hot springs by means of magnetic and electromagnetic methods can help infer the occurrence of structures which are favourable for groundwater potential. The Polile Tshisa hot spring is characterised by faults, fractures, and dolerite dykes. All these structures make the hot spring a good case study for groundwater exploration.
EN
Tectonic research and morphological observations were carried out in six caves (Kalacka, Goryczkowa, Kasprowa Niżna, Kasprowa Średnia, Kasprowa Wyżnia and Magurska) in the Bystra Valley, in the Tatra Mountains. There are three cave levels, with the youngest active and the other two inactive, reflecting development partly under epiphreatic and partly under phreatic conditions. These studies demonstrate strong control of the cave pattern by tectonic features, including faults and related fractures that originated or were rejuvenated during uplift, lasting from the Late Miocene. In a few local cases, the cave passages are guided by the combined influence of bedding, joints and fractures in the hinge zone of a chevron anticline. That these cave passages are guided by tectonic structures, irrespective of lithological differences, indicates that these proto-conduits were formed by “tectonic inception”. Differences in the cave pattern between the phreatic and epiphreatic zones at a given cave level may be a result of massif relaxation. Below the bottom of the valley, the effect of stress on the rock mass is related to the regional stress field and only individual faults extend below the bottom of the valley. Thus in the phreatic zone, the flow is focused and a single conduit becomes enlarged. The local extension is more intense in the epiphreatic zone above the valley floor and more fractures have been sufficiently extended to allow water to flow. The water migrates along a network of fissures and a maze could be forming. Neotectonic displacements (of up to 15 cm), which are more recent than the passages, were also identified in the caves. Neotectonic activity is no longer believed to have as great an impact on cave morphology as previously was thought. Those faults with displacements of several metres, described as younger than the cave by other authors, should be reclassified as older faults, the surfaces of which have been exposed by speleogenesis. The possible presence of neotectonic faults with greater displacements is not excluded, but they would have had a much greater morphological impact than the observed features suggest.
15
Content available remote The Quaternary transformation of older inherited mountain landscapes
EN
The Quaternary transformation of the inherited mountain relief was controlled by three factors: cyclic climatic changes, resistance of the substratum and neotectonic uplift. Cyclic climatic fluctuations in the majority of European mountains were reflected in the alternation of interglacial and cold stages, the former characterized by a dominance of forest and chemical weathering, the latter by permafrost, solifluction, wind activity and, at higher elevations, by glacier advances. The transitinal phases played an important role as periods of reestablishment of water circulation and transfer of regolith and sediment, formed during the previous cold or interglacial stage. The rates of degradation of inherited planation surfaces and slopes depend on bedrock resistance. In the case of less resistant flysch deposits, degradation during a single (last) cold stage reached 10 metres. Therefore, the higher planation levels may have been either better preserved on more resistant bedrock or even emphasized by cryoplanation processes. The lowest piedmont developed on less resistant beds was lowered to 50 m. In the young mountains, the Quaternary uplift may have played an additional role. In the case of uplift reaching or exceeding several hundred metres, the former fluvial forms were shifted to the cryonival or even nival (glacial) vertical zone where they became entirely transformed.
EN
The main relief features of the Lublin Upland (sensu Jahn, 1956) and Roztocze were formed during the early and middle Cenozoic stages of the Meta-Carpathian Ridge morphogenesis. They are clearly conditioned by the structure of the Upper Cretaceous-Palaeogene complex of the marginal part of the East European Craton. The following factors were of fundamental significance for the relief development in the study area: 1) Alpine and modern tectonic activity, which conditioned the horst nature of some morphostructures and the type of fissuring of rock massif, and 2) lithological diversity of the Upper Cretaceous-Palaeogene complex as well as the Miocene and Pliocene deposits, which influenced its strength features.
17
Content available remote Tectonics of the Upper Nysa Kłodzka Graben, the Sudetes
EN
The Upper Nysa Kłodzka Graben is a geological unit well identifiable on geological, topographical and digital elevation model (DEM) maps. Tectonic activity in the area dates back to the Late Cretaceous, when the frames of the tectonic trough were formed due to the uplift of the Śnieżnik Massif Range in the east, Krowiarki Mts. Range in the north and the Bystrzyca Mts. and Orlicka Mts. ranges in the west. The total vertical displacement between the deepest locations in the graben and the highest peaks in the Śnieżnik Range varies between 1200 and 1700 m. The vertical differences in topographical relief of the graben basement exceed 500 m. Although the Upper Nysa Kłodzka Graben extends NNW–SSW, concordantly with the trend of mountain ridges in the Śnieżnik Range, subordinate tectonic structures within the graben trend N–S in its southern part near Králíky and NW–SE in the middle and northern parts. The trends of the subordinate tectonic structures are, thus, parallel to the main mountain ranges in the Orlica Mts., Bystrzyca Mts. and Krowiarki Mts. The most intensive vertical movements took place in the Late Touronian, Coniacian, at the turn of the Creataceous and Tertiary, in the Paleogene and Early Neogene. Although the Late Neogene and Quaternary activity in this area is not well documented, the vertical displacement along faults is assessed at ~70 m. The presence of volcanic rocks covering river gravels in Lądek Zdrój, thermal and mineral springs as well as the occurrence of minor earthquakes in historical times point to tectonic activity also in the Pleistocene. Recent tectonic activity in the Upper Nysa Kłodzka Graben area is evidenced by geodetic measurements and microseismicity recorded over the adjacent East Sudetes area.
PL
W opracowaniu zaprezentowano schemat działania narzędzia ArcNEO, zwiększającego funkcjonalność programu ArcGIS 10.1 i pozwalającego na typowanie obszarów względnie mobilnych tektonicznie. Narzędzie ArcNEO działa w oparciu o dane wektorowe (granice zlewni poszczególnych rzędów, wybrane profile poprzeczne zlewni, dla których wyznacza się wartości wskaźnika Vf, szerokość dna doliny) oraz cyfrowy model wysokościowy (CMW). Generuje ono parametry zlewni oraz trzy grupy wskaźników: dwie (wysokościowe i powierzchniowe) opisujące parametry zlewni oraz jedną (liniową) – opisującą cechy form rzeźby w zlewniach. Wielkości wskaźników są podstawą do oszacowania młodej mobilności tektonicznej. Działanie narzędzia ArcNEO przedstawiono na przykładzie zlewni górnego Wieprza, położonej na lubelskim obszarze wyżynnym. Opracowana aplikacja może być stosowana do wskazywania obszarów względnie aktywnych/nieaktywnych tektonicznie w innych regionach o stosunkowo jednorodnej budowie geologicznej, a także do określania charakterystyk fizjograficznych zlewni.
EN
The current study presents the function of the ArcNEO tool, which increases the functionality of the ArcGIS 10.1 software and facilitates identification of relatively mobile tectonic areas. The ArcNEO tool works on vector layers (boundaries between catchments of different orders, selected transverse catchment profiles with their calculated Vf index values, the width of the valley floor) and the digital elevation model (DEM). The tool generates catchment parameters and three groups of indices: two (elevation and surface) describe catchment parameters and one (linear) describes the characteristics of catchment relief. The values of the indices are used in estimation of new tectonic mobility. The function of the ArcNEO tool is presented on the example of the upper Wieprz catchment located in the Lublin Upland area. The application developed can be used to identify relatively active/inactive tectonic areas in other regions characterised by a relatively homogeneous geological structure and to provide physiographic features of catchments.
EN
The paper presents the first example of Holocene faults in the OuterWestern Carpathians in Poland. Small-scale normal faults at Koninki, Gorce Mts., cut both Palaeocene strata of the Ropianka Formation of the Magura Nappe and overlying coarse-clastic bedload facies of Holocene alluvium that builds a 5-5.5-high terrace step of a small valley. These NE-trending faults are accompanied by reorientation of clast a-b planes subparallel to fault planes and by clast fracturing. Such deformations must have been induced by relatively strong earthquakes, unknown from historical record of the Outer Carpathian seismicity. Fault attitude points to NW-oriented axis of the minimum principal stress, which is compatible with parameters of the present-day stress field in the Outer Western Carpathians of Poland.
20
Content available remote Active faulting and deformation of quaternary landform Sub-Himalaya, India
EN
Landforms developed across terrain defining boundary the Main Boundary Thrust (MBT) have imprints of recent tectonic activity. Depositional landforms such as colluvial fan bear signatures of later phases of tectonic activity in the form of faulting of colluvial fan deposits and development of fault scarps. Tectonic geomorphology applied to the MBT zone suggests recent subsurface activity along the MBT and its splay thrusts. Present day tectonic activity of MBT is indicated by ground creeping, thrusting of Lower Siwalik rocks over recent colluvial fan deposit, aligning of series of lakes along splay faults and laterally along a fault, deflected streams, fault scarps and waterfalls. In the present paper we are addressing the tectonic situation in the foothill region of southeastern Kumaun Sub-Himalaya, India based on detailed field work carried out in the region which brought forward some outstanding morphotectonic evidence of neotectonic activities in the MBT zone.
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