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EN
The neo-tectonic research is interested in the study of the movements of Earth’s crust in recent geological times. It could explain the deformation mechanisms that lead to the structuring of drainage catchments. The Morsott-Tebessa-Youkous (Chabro) collapsed basin corresponds to a subsiding depression framed by brittle structures and filled with thick deposits. Our work aims to unveil the neo-tectonic activity and reconstruct the morphometric evolution of the landscape and the drainage network of the basin. For this task, our investigation applies a quantitative analysis of geomorphic indices extracted from the DEM of the study area. We used a GIS-based approach to compile seven morphometric factors namely Integral Hypsometry (HI), the Sinuosity of mountain fronts (Smf), the Valley Floor width to height ratio (VF), the Asymmetry Factor (AF), Basin Shape index (BS), and the topography (T). All these thematic parameters were processed in a Geo-database to calculate the study area’s Relative Tectonic Activity Index (IRAT) as a result. The IRAT map was categorized into three classes. The result highlighted the distribution of relative tectonic activity in the region and unveiled some unknown faults. It associated the sinuosity of rivers and the deformation of the substratum with active tectonic anomalies. This research work succeeded in drawing up a new scheme of the neo-tectonic activity and morphostructural evolution in the collapsed basin.
PL
Artykuł przedstawia wyniki badań aktywności tektonicznej prowadzonych przez Laboratorium Geodynamiczne CBK PAN w kontekście możliwości wdrożenia nowej metody pomiarowej na rzecz monitoringu zagrożeń w górnictwie węgla kamiennego i miedzi.
EN
Recognition of high coincidence of intervals of Iow velocities of Świebodzice Depression deformation with intervals of seismic events in underground mines (for ca. 140 of strong events in 2006-2016) supports the concept of a large-scale tectonic force field, which source area is the Atlantic rift system. This field covers areas of the Świebodzice Depression, Fore-Sudetic Monocline, Upper Silesian Basin and Bohemian Massif, which explains the cause of the observed coincidence. Practical application of the findings described (called „TAF method") allows for determining the so-called PGZ parameter - momentary susceptibility of rock massif to destruction. The PGZ parameter allows to assess the momentary level of seismic shock threat at a several level scalę. The TAF method may be applied to determine intervals of increased seismic shock threat almost in real time after modernisation of the registration process. To achieve this, analogous modules should be replaced by digital measurement systems. Application of the TAF method should improve exploitation safety in underground mines and selection of optimal moments for rock massif release (with application of blasting method) in intervals of high PGZ values, i.e. large susceptibility of rock mass to destruction.
EN
The present study deals with the soil gas geochemical surveys in and around Shanchiao fault to pick the sites for integrated radon monitoring using SSNTDs to better understand the response of tectonic activity of the fault systems. Throughout these surveys, gathered samples of soil gas has been analysed for radon and carrier gases namely CO2, He, N2, O2, CH4 and Ar. The RAD 7 instrument has been utilized for radon analysis and gas chromatograph instrument for analysing the carrier gases. The predominance of gas spread has been explored based on the results of these surveys and three sites have been chosen for integrated observation with regard to seismotectonic activity to examine the affectability of the sites utilizing SSNTDs. From these sites, a site will be chosen for future long duration continuous observance on the premise of its affectability towards the seismotectonic activity inside the territory.
4
PL
Geomorfologia tektoniczna jest dynamicznie rozwijającą się dziedziną nauki – głównie za sprawą nowych możliwości badawczych, które pojawiły się wraz z rozwojem narzędzi udostępnianych za pośrednictwem Geograficznych Systemów Informacyjnych (GIS) oraz z wprowadzeniem cyfrowych zestawów danych wysokościowych. Dzięki temu rozwijany jest przede wszystkim ilościowy kierunek tych badań. Niniejsza praca ma charakter przeglądowy. Zestawiono w niej, podzielono oraz omówiono wskaźniki morfometryczne wykorzystywane w badaniach nad młodą aktywnością tektoniczną obszarów, zwracając jednocześnie uwagę na ograniczenia interpretacyjne związane z ich wykorzystywaniem. Przegląd literatury uwzględnia opracowania zarówno polskie, jak i zagraniczne opublikowane w latach 2000–2015.
EN
New research possibilities that emerged from the development of Geographic Information Systems (GIS) and digital topography underpin the growth of tectonic geomorphology, mainly in respect to quantitatively oriented investigations. This paper presents a review of morphometric parameters that have been applied in morphotectonic studies in Poland and worldwide and is essentially based on papers published from 2000 to 2015. Classification of tectonic activity indicators is presented, as well as limitations in their interpretation are discussed.
EN
Coregonid fishes (coregonids) (Salmonidae, Coregoninae) of Siberia show immense morphological and ecological variability, what is reflected in their complex interspecific and intraspecific structure: i.e. occurrence of numerous species, forms and endemic species. Studies of the coregonids of Siberia is crucially important for understanding of their origin, taxonomy and evolution. We have analysed electrophoretically some 13 enzyme systems from over 20 samples of East-Siberian coregonids. This paper was intended as an introduction to a number of primary papers that are planned that will describe the biological and genetic characteristics of studied populations.
9
EN
This paper summarizes recent research activities on merging the geodetic, geologic and neotectonic evidence of geodynamics in Croatia. The area of the City of Zagreb, which is the boundary zone of Eastern Alps, Dinnarides and Pannonian Basin is included as well. It is shown here that the evidence for fractures of Eastern Adriatic differs from the previous hypotheses. This conclusion is derived from the results of various geodetic measurements: satellite positioning (GPS), astro-geodetic measurements of deflections of the vertical. These results are combined with geologic measurements and results of seismic activity studies in order to give more detailed and more accurate picture of the current situation in the tectonically very active region of Dinnarides. Several GPS-campaigns performed in the City of Zagreb area are examined as well. Due to the proximity of Croatian capitol, special attention has been paid to the effects of possible hazard on construction code.
EN
Normal faults of different orientations appear to be the youngest manifestations of faulting in the Carpathian Foredeep which is filled with Lower to Middle Miocene sediments. Structural studies of the Late Miocene–Pliocene(?) fresh-water molasses of the Witów Series and the overlying Late Pleistocene loessial complex provide a possibility to reconstruct the Late Neogene to Recent (?) stress field in the central part of the Polish Carpathian Foredeep. Strata of such a young age are very rare in the foredeep, thus providing a key record of structural deformation during the latest stages of orogenic evolution of the Carpathian orogen. The molasses are cut by joints, and normal and strike-slip faults, formed in two successive events: (1) a syn-depositional one for the molasses (Late Miocene–Pliocene?), proceeding under NNW–SSE to N–S-oriented horizontal compression, possibly coeval with reactivation of a NE-striking sinistral fault of the Kurdwanów–Zawichost Fault Zone in the basement; (2) a post-depositional one for the molasses (Pliocene to Middle Pleistocene) during N–S to NE–SW-oriented extension, and (3) both syn- and post-depositional ones for the loessial complex (Late Pleistocene). In the first event, reactivation of the NE-striking sinistral fault led to formation of N–S-oriented joints, as well as NW-striking dextral, and NNW-trending normal faults. In the second event, both W–E and NW–SE – oriented joints andWNW-striking normal faults were formed. The latter most probably originated due to reactivation of the Early Palaeocene WNW- and NW-striking normal faults in the basement. In the third event, both NE–SW and NW–SE-oriented joints and NE-striking normal faults formed as a result of reactivation of the SW- and WSW-striking faults in the basement. Therefore, normal faults detected in the Carpathian Foredeep appear to be a result of different successive events. This extensional episode lasted at least to the Late Pleistocene. We also provide evidence for the recent, N- to NNE-directed, tectonic compressive stress, typical for that segment of the Carpathian arc. This stress resulted in the formation of an orthogonal system of joints striking N–S and W–E, produced during
EN
Analysis of deposition rate were performed for synthetic sections, representing the upper Jurassic to lower Miocene sedimentary fill of the Western Outer Carpathian (WOC) basins. Calculated deposition rates differs in a range of a few orders of magnitude. During Tithonian to Berriasian-early Valanginian tectonic activity of the source areas supplying the Silesian Basin was related to the mechanism of syn-rift extensional elevation and erosion of horsts. General decay of source area activity in Valanginian to Cenomanian time was caused by regional post-rift thermal sag of the WOC. The Barremian to Albian phase of compressional uplift of the source area located north of the WOC lead to increase of deposition rate in some zones of the WOC basin. In Turonian to Paleocene time thick-skinned collision and thrusting took place south and south-west (in the recent coordinates) of the Silesian Basin causing very rapid, diachronous uplift of this zone, referred to as Silesian Ridge, resulting with high deposition rate in the Silesian Basin. At that time supply of sediments to the Magura Basin from south was relatively low, and the Pieniny Klipen Belt was presumably zone of transfer of these sediments. In Eocene the zone of collisional shortening in the WOC system was relocated to the south, causing rapid uplift of the Southern Magura Ridge and intense supply of detritus to the Magura Basin. Thrusting in the Southern Magura Ridge and collisional compression resulted with flexural bending of its broad foreland, being the reason for decrease of activity of both the Silesian Ridge and the source area at the northern rim of the WOC. The Eocene evolution of the Silesian Ridge is interpreted as controlled by both episodic tectonic activity and eustatic sea level changes. Contrasting development of the Southern Magura Ridge and the northern rim of Central Carpathians during Eocene stands for a palaeographic distance between the two domains at that time. During Oligocene and early Miocene a significant increase of deposition rates is observed for the basin in which sediments of the Krosno beds were deposited. This was caused by tectonic uplift of the source at the northern rim of the WOC, as well as the Silesian Ridge and the partly formed Magura nappe. The Miocene molasse of the WOC foredeep basin is characterised by notably higher maximum deposition rates than ones calculated for the flysch deposits of the WOC.
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