Coastal erosion is one of the major problems in coastal management. To adapt to it, and prevent it where possible and needed, it is important to recognize the temporal and spatial scale of the phenomenon as well as its causes. This paper describes the rapid erosion rate along an approximately 2.25 km stretch of the southern Baltic coast. The erosion occurs within a nature reserve, which is not subject to direct anthropogenic impact. Historical maps and modern remote sensing were used to trace changes in the shoreline position from 1875 to the present, and detailed DTMs derived from airborne LiDAR were used to trace elevation changes of the beach and dunes over the past years. The weighted maximum annual erosion rate since 1875 averages 2.3 m. An increase in this annual erosion rate has been observed since the turn of the millennium. The maximum average erosion rate from 2001 to 2005 was 15 m/year. The erosion has caused serious changes in elevation within the inland part of the coastal zone, manifested by a reduction in the width of the beach and a decrease in the height of the beach and dunes.
The research task Geological integrated coastal zone mapping concerns the recognition and visualization of the geological structure of the Polish coastal zone, enriched with the modelling of erosion-accumulation processes, including prediction of changes in the position of the shoreline and identification of geohazards. It has been running since 2012 and implements multi-instrumental research methods. To date, a total length of about 155 km of the Polish coastal zone has been studied in an area of about 621 km 2 . The main results of the work are presented in the form of maps (e.g., lithogenetic, hydrogeological, geohazard), models (e.g., morpho-geological, hydrodynamic, predictive) and specialized analyses (e.g., morphodynamical, slope stability). In general, the work carried out is done for a utilitarian purpose, i.e. aimed at the practical use of environmental information. According to the standards of the Polish Geological Survey, most of the geological data acquired can be geoprocessed.
Geological hazards caused by landslides, earthquakes, erosion, land surface deformation and collapse in 2021 in Poland were among the average compared to recent years. They did, however, affect material losses. The Polish Geological Survey (PGS) recorded 41 events related to sudden landslide activations, which damaged or destroyed 17 road sections. Through ongoing monitoring of 72 landslides, 33 were shown to be active. In 2021, more than 5,200 landslides were identified and inventoried in Poland. Geodynamic monitoring performed by PGS recorded 611 seismic events in Poland, whose magnitudes reached M4.2. In addition, using satellite radar interferometry, continuation of land surface deformations was found mainly in mining areas. In 2021, there was a number of collapses of various origins. The paper is a brief report on the ongoing tasks of the Polish Geological Survey in the field of geological hazards and presents events that took place in Poland in 2021.
Projektując roboty i badania geologiczne złoża kopaliny zakłada się uzyskanie pożądanej dokładności (kategorii) rozpoznania budowy geologicznej, warunków hydrogeologicznych, geologiczno-inżynierskich i innych, określanych hasłowo warunkami geologiczno-górniczymi. Chociaż dokładność rozpoznania złoża w takim zakresie da się przedstawić głównie w formie opisowej i graficznej, prowadzi to jednak do odpowiednio dokładnego obliczenia zasobów kopaliny i średnich parametrów złoża, a niekiedy także liczbowo przedstawianej charakterystyki zmienności parametrów złoża i cech kopaliny. Obliczając zasoby i średnie parametry złoża podczas sporządzania dokumentacji geologicznej złoża kopaliny na lądzie opieramy się na populacji danych uzyskanych bezpośrednio z profili geologicznych otworów i odsłonięć oraz z badań próbek pobranych z tych profili. Dane te pozwalają w prosty sposób na obliczenie błędów oszacowania średnich parametrów złoża i zasobów, co jest wymagane przez stosowne przepisy. Obliczone wielkości błędów wskazują na rozpoznanie złoża w określonej kategorii. Jest to szczególnie ważne w kategorii rozpoznania C1, która pozwala na opracowanie projektu zagospodarowania złoża, niezbędnego dla ubiegania się o koncesję na wydobycie kopaliny. Metodyka badań złóż kruszywa naturalnego położonych na dnie Morza Bałtyckiego jest nieco inna. Podstawowymi są badania geofizyczne, sejsmoakustyczne oraz sonarowe. Wiercenia wykonuje się w mniejszej liczbie, niż na lądzie i do maksymalnych głębokości wynikających z możliwości technicznych oraz ograniczeń środowiskowych. Położenie naturalnego spągu złoża nie ma praktycznie wpływu na głębokość wierceń. Strop złoża stanowi zawsze powierzchnia dna morskiego dająca się odwzorować na mapie z dokładnością niemal rzeczywistą. Powierzchnię naturalnego spągu serii złożowej obrazują głównie dane z gęstej siatki profili sejsmoakustycznych. Rdzenie profili wykonanych wierceń służą przede wszystkim do opisu litologii kopaliny oraz do poboru próbek do badań laboratoryjnych. Większość złóż kruszywa udokumentowanych na dnie Bałtyku, w jego części będącej we władaniu Rzeczpospolitej Polskiej, jest rozpoznana w kategorii C2, mniej dokładnej, niż kategoria C1. Analizy dokładności oszacowania średnich parametrów złoża i zasobów nie były wykonane, ponieważ nie było to formalnie wymagane. Niniejszy artykuł jest próbą znalezienia sposobu dokonania takiej analizy metodami matematycznymi, uwzględniającymi specyfikę metodyki badań morskich.
EN
When planning geological research and exploration of a mineral deposit, it is assumed to obtain the desired accuracy (category) of recognition of the geological structure, hydrogeological, geological-engineering and other conditions, which are referred to as ‘geological-mining conditions’. Although the accuracy of deposit recognition in such range can be presented mainly in descriptive and graphical form, it leads to appropriately precise calculation of mineral resources and average parameters of the deposit, sometimes also numerically presented characteristics of variability of deposit parameters and mineral characteristics. When calculating resources and average parameters of a deposit during preparation of geological documentation for terrestrial deposits, we rely on the population of data obtained directly from geological profiles, exposures and analyses of samples taken from these profiles. These data allow for simple calculation of uncertainty estimation of deposit average parameters and resources, which is required by relevant legislation. The calculated error indicates recognition of a deposit in a given category. This is especially important in the case of the C 1 recognition category, which allows for drawing up a ‘deposit development plan’, a document required when applying for a exploitation license. Methodology of investigating natural aggregate deposits located offshore, at the seabed (including Baltic Sea) is slightly different. Geophysical, seismic-acoustic and sonar surveys are basic. Drilling is carried out in lesser amounts than on land and to maximum depths resulting from technical possibilities and environmental constraints. The location of the deposit natural base has practically no influence on the drilling depth. The seabed is always the top surface of the deposit, which can be mapped with almost real accuracy. The surface of the deposit natural base is represented mainly by data derived from a dense net of seismic-acoustic profiles. The sediment cores are used mainly for lithology description of the mineral and for laboratory tests. Most of the mineral deposits documented on the seabed of the Polish part of the Baltic Sea are classified as C 2, less precise than C1 category. Accuracy analyses of deposit average parameters and resources estimation, were not carried out because it was not formally required. This article is an attempt to find a way of making such analysis using mathematical methods, taking into account specificity of offshore exploration methodology.
The paper describes geohazard events that took place in 2020 on the territory of Poland. The PGI is responsible for geohazard monitoring in four areas of interest :landslides and mass movements within the Landslide Counteracting System (LCS, SOPO in Polish), earthquakes within the Geodynamical Monitoring of Poland and ground motions within the Interferometric Terrain Deformations Monitoring of Poland, and coastal monitoring carried out by the Marine Geology Branch within a framework of the 4D Cartography. In 2020, there were no spectacular geohazard events; however, there were some permanently active phenomena, mostly landslides, which caused significant damages to the infrastructure.
Research by the Polish Geological Survey has been carried out along the southern Baltic coastal zone over a distance of 38 km. The Baltic Sea is classified as non-tidal, and its southern coasts are built entirely of weakly lithified sedimentary rocks. These deposits form three main types of coast, namely cliffs, barriers and alluvial coasts (wetlands), with the research focusing on the first two. Methods including remote sensing, mapping (geological, hydrogeological), offshore survey (bathymetric and geophysical measurements), laboratory analyses and modelling revealed a number of natural hazards. These are, respectively: (1) permanently occurring hazards, causing material damage such as: landslides, coastal erosion and seabed erosion; (2) incidental hazards such as dune breakage and storm surge overflow and (3) hypothetical threats that may occur in the future, such as hydrogeohazards defined here as flooding resulting from groundwater level rise or more rarely, earthquake threats.
The paper presents the results of the first OSL dating of glaciofluvial and ice-marginal lake sediments which occur between end moraines of the Słupsk Bank and the Polish coast. The sand and gravel of glaciofluvial deltas on the Słupsk Bank were deposited most likely during a period from 14.3 ±1.2 to 16.6 ±1.4 ka ago. The deposition of silty-sandy sediments of the ice-marginal lake is dated at 14.51 ±0.81 and 14.6 ±1.4 ka years. Likewise, dates ranging from 13.74 ±0.84 to 16.70 ±1.1 ka obtained from low sandy ridges, related to the southern range of the ice-marginal lake in the Gardno-Łeba Lowland, indicate the most likely timing of their deposition. It can be concluded that a short stop of the ice sheet on the Słupsk Bank took place approximately 15.2 ka ago, which could be correlated with the position of the ice sheet front in central Skåne and in northern Lithuania at that time. Older and younger results were also obtained, except the dates mentioned above. The older ages show little sunlight exposure of sediments during their deposition. The younger dates indicate a marine origin of the sediments and show that some parts of glaciofluvial sediments were redeposited and exposed to sunlight at a later stage, most probably when dead-ice blocks were melting.
The Szamotuły Graben covers the southernmost part of the Permo-Mesozoic Poznań–Szamotuły Fault Zone. Along this regional discontinuity there are several salt structures, including the Szamotuły diapir, over which an extensional graben formed in the Paleogene and Neogene. The graben is located north of Poznań in central-western Poland, and is NW–SE-trending, ~20 km long, 3–5.5 km wide, and up to 160 m deep. It is filled with Lower Oligocene and Neogene sediments, including relatively thick lignite seams. Data from boreholes allow the assignment of the graben-fill sediments to appropriate lithostratigraphic units. Furthermore, analysis of changes in the thickness of these units provides evidence for periods of accelerated graben subsidence or uplift relative to its flanks. As a result, two distinct stages of tectonic subsidence and one inversion in the Paleogene–Neogene evolution of the Szamotuły Graben have been distinguished. Thus, relatively significant subsidence occurred in the Early Oligocene and the middle Early–earliest Mid-Miocene, while slight inversion took place in the middle part of the Mid-Miocene.
Kratery meteorytowe Kaali (wyspa Saaremaa, Estonia) stanowią unikatowe miejsce w Europie, nie tylko ze względu na wyjątkową formę wykształcenia, ale także dostępność do badań metalicznej materii pozaziemskiej. Podczas badań terenowych prowadzonych w maju 2004 roku autor zgromadził próbki osadów, które posłużyły do badań drobnej frakcji materii magnetycznej występującej w obrębie kraterów meteorytowych Kaali. Na podstawie morfologii, cech powierzchni i składu chemicznego wyselekcjonowanych ziaren magnetycznych wyróżniono cztery grupy materii: (1) kosmiczne kulki zbudowane z tlenku żelaza, zawierające nikiel, (2) kulki węglowe, które wstępnie zaklasyfikowano jako antropogeniczne, (3) kulki krzemianowe interpretowane jako zestalone krople wymieszanej materii ziemskiej i pozaziemskiej, i (4) płytki zbudowane z tlenku żelaza, pozbawione niklu, które zinterpretowano jako zwietrzałe pozostałości materii pozaziemskiej. Opis morfometryczny kraterów Kaali został sporządzony na podstawie danych literaturowych oraz wizji lokalnej przeprowadzonej przez autora.
EN
The Kaali meteorite crater field is a unique place in Europe, not only because of its morphology but also because of the presence of large amounts of extraterrestrial material. During field work in May 2004, samples were collected at this site with the objective to study magnetic fines. Based on morphology, surface features and chemical composition of the selected magnetic material, four groups of spherules and plates were distinguished: (1) Ni-bearing Fe-oxide spherules of cosmic origin, (2) carbon spherules tentatively classified as anthropogenic, (3) silicate spherules interpreted as solidified droplets of mixed terrestrial and extraterrestrial matter, and (4) Ni-free Fe-oxide plates interpreted as weathered remnants of extraterrestrial material. The Kaali crater site is described morphologically on the basis of literature and the author’s own observations.
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