Identification of a circular structure in eastern Pomerania (northern Poland) : a hypothesis of its origin

The possible existence of a circular structure in the Kościerzyna region (northern Poland) was suggested in two papers in the 1980s. The current studies were aimed at verifying this hypothesis. Analysis of a digital terrain model of the pre-Quaternary surface relief as well as of the present terrain revealed the existence of a large structure of ca. 50 km in diameter. Its geometry was established based on a model of the Neogene/Pliocene surface and identifiable lineaments. Its characteristic feature is the presence of rim-like forms, an internal plateau, and a “high” in the centre. The structure is estimated to date from before the Pleistocene. The circular structure has been reshaped by glacial erosion and accumulation, and is now buried under Quaternary deposits. The existence of the Kościerzyna circular structure was confirmed by conducted studies, but my hypothesis of an impact origin is still uncertain and needs to be confirmed by future research

Pierwiastki ziem rzadkich w konkrecjach Fe-Mn z południowego Bałtyku – badania wstępne

Between 1976–1990, the Polish Geological Institute performed geological works in the Polish Maritime Areas. During these works, 260 occurrences of concretions were recorded from 7,500 sampled sites. In 1980, the threshold that separates the Bornholm Basin from the Słupsk Furrow was mapped. Numerous Fe-Mn nodules on the seabed were found in that area. The results of detailed analyses of nodule samples collected from four sites are presented in this paper. Analyzed nodules represent discoidal D, irregular I, and transitional D-I types. The nodules are characterized by varied chemical composition of main oxides (Fe, Mn). The maximum Fe2O3 content is 26.63% and MnO 23.18%. Total average amount of REE + Y in the samples is approximately 165.11 ppm, ΣLREE 145.72 ppm and ΣHREE 19.39 ppm. The LREE content is enriched in comparison to HREE. The majority of nodules consist of Fe-Mn oxy-hydroxide minerals with very low crystallinity (practically amorphous phases). The main confirmed Mn-phases are birnessite and todorokite. Other main components of the nodules are: detrital quartz, albite, microcline, glauconite and muscovite, clinochlore, and clay minerals: illite and chlorite. The rate of growth of Fe-Mn nodules has been estimated using a cobalt chronometer. The nodule growth rate ranges from 0.006 to 0.134 mm/yr –1. Based on the Fe, Mn and (Cu + Co + Ni) contents, the origin of studied nodules is determined as hydrogenetic, while using REE (Cesn/Cesn • vs. Nd) – as diagenetic.W latach 1976–1990 Państwowy Instytut Geologiczny realizował prace geologiczne na Polskich Obszarach Morskich. Opróbowano 7500 miejsc, a w 260 stwierdzono występowanie konkrecji. W roku 1980 prace kartograficzne prowadzono m.in. na obszarze progu oddzielającego Basen Bornholmski od Rynny Słupskiej, gdzie stwierdzono występowanie licznych konkrecji Fe-Mn. W niniejszym artykule są prezentowane wyniki analiz konkrecji pobranych na 4 stanowiskach. Badania dotyczą konkrecji następujących typów: dyskoidalnych D, nieregularnych I oraz przejściowych D-I. Badane konkrecje charakteryzują się zmiennym składem głównych tlenków (Fe, Mn). Maksymalna zawartość Fe2O3 wynosi 26,63%, a MnO 23,18%. Łączna średnia zawartość REE + Y w badanych próbkach jest na poziomie 165,11 ppm, ΣLREE – 145,72 ppm i ΣHREE – 19,39 ppm. Zauważalne jest wzbogacenie w LREE w porównaniu do HREE. Konkrecje w większości są zbudowane z tlenków i wodorotlenków Fe i Mn o bardzo niskim stopniu krystaliczności (praktycznie fazy mineralne są amorficzne). Głównymi potwierdzonymi fazami manganu są birnessyt i todorokit. Pozostałymi głównymi składnikami konkrecji są: kwarc terygeniczny, albit, mikroklin, glaukonit i muskowit, klinochlor, minerały ilaste: illit, chloryt. Wartość tempa wzrostu w badanych konkrecjach, określona z użyciem chronometru kobaltowego, wynosi od 0,006 do 0,134 mm/yr –1. Na podstawie zawartości Fe, Mn oraz (Cu + Co + Ni) badane konkrecje określono jako hydrogeniczne, podczas gdy używając zależności REE (Cesn/Cesn • vs. Nd) jako diagenetyczne

Foot mechanics in young women are altered after walking in high-heeled shoes

Nowadays, fashion has caused that many young women are wearing high-heeled shoes. Therefore, the aim of this study was to examine the effects of long-term walking in high-heeled shoes on the foot mechanics during barefoot gait. Methods: Forty-three young women (22 ± 2.1 years) divided into two groups participated in this retrospective cohort study. The first group was composed of women who frequently wear high-heeled footwear. The second, infrequent wearers group, consisted of women who preferred flat-heeled shoes. Measurements of gait parameters were recorded for barefoot gait. A motion analysis system and two force plates were used in order to evaluate the lower-limb rocker mechanism, transverse foot arch height and parameters of ground reaction force. Results: Walking in high-heeled shoes modified barefoot foot mechanics, which manifested itself in a shorter duration (by ca. 4%) of the first and second rocker and a significantly longer duration (by 5%) of the third rocker phase as well as a substantial reduction in height of the transverse foot arch (by around 50%) in women habitually walking in high-heeled shoes. A significantly shorter relative duration of the third rocker (44.3% of cycle time) and greater value of the vertical component of ground reaction force (114.7% BW) in the third rocker phase were found in the group of women habitually walking in high-heeled shoes. Conclusions: The mechanism of foot rolling, with flattened foot arch, and significantly higher values of the vertical component of ground reaction force and shorter time might lead to overload in lowerlimb joints in young women

Issues concerning the application of satellite interferometry in geological investigations

Przedstawiono problematykę wykorzystania interferometrii radarowej do badania geodynamiki i ruchów powierzchni terenu wybranych obszarów Polski. Zinterpretowano wyniki tej metody dla Górnośląskiego Zagłębia Węglowego (GZW) oraz południowego wybrzeża Bałtyku w rejonie Zatoki Gdańskiej. Omówiono możliwości i ograniczenia satelitarnej techniki radarowej do badania analizy przemieszczeń powierzchni terenu. Dla obszaru GZW zastosowano dwie metody: PSI (satelity ERS-1 i ERS-2) oraz DifSAR (japoński satelita ALOS), które wykazały dużą użyteczność w badaniach osiadań terenu na obszarach górniczych i pogórniczych. Do analizy geodynamiki południowego wybrzeża Bałtyku w rejonie Zatoki Gdańskiej zastosowano metodę PSI. Zaobserwowano, że przeważająca część aglomeracji Gdańska, Gdyni i Sopotu jest stabilna lub prawie stabilna. Jednym z wyjątków jest obszar rafinerii gdańskiej, gdzie odnotowano osiadania sięgające –12 mm/rok. Stwierdzono, że interferometria radarowa jest bardzo przydatna do oceny ruchów powierzchni terenu – zagadnienia często rozpatrywanego w praktyce geologiczno-inżynierskiej.The questions of the satellite interferometry method application for research studies of the geodynamics and ground movements in selected areas of Poland have been presented in this paper. The results of interferometric analysis from Upper Silesian Coal Basin (USCB) and Southern Baltic Coasts in the region of Gdańsk Bay were revealed. The advantages and limitations of the satellite interferometry for the ground movements studies have been also discussed. In the USCB area two interferometric methods were applied: PSI (based on the analysis of the data from satellites ERS-1 and ERS-2) and DifSAR (based on the analysis of the data from the Japanese satellite – ALOS). The results of interpretation have shown big utility for investigations of subsidence at the mining and post mining areas. On the basis of the PSI analysis of Southern Baltic Coasts several interesting phenomena have been observed. It was confi rmed that predominant part of Gdańsk-Gdynia-Sopot agglomeration is stable or nearly stable. One exception has been observed in the region of the Gdańsk Refinery, where the subsidence rate of 12 mm/year was confi rmed. On the basis of the presented examples it could be concluded that the satellite interferometry is extremely useful for ground movement studies in the engineering-geological practice

PSI analysis of ground deformations along SW coast of the Gulf of Gdańsk

The paper presents results of SPINUA (Stable Point Interferometry over Unurbanised Areas) Persistent Scatterers Interferometry (PSI) processing chain to study Earth surface deformations along the SW coast of the Gulf of Gdańsk, along the SE part of the Baltic Sea. As the input for SPINUA techniques 40 descending ERS-1/2 SLC (Frame = 251, Track = 36) images from the period 1995-2001 has been used. The area of interest (AOI) includes few cities and several towns, villages and harbors. The low lying coastal areas of the SW part of the Gulf of Gdańsk are at risk of floods and marine erosion. The PSI results, however, did not reveal the presence of a regional scale, spatially consistent pattern of displacements. It is likely that any crustal deformations in the AOI simply do not exceed +2 mm/year, which is the velocity threshold we assumed to distinguish between moving and non-moving persistent scatterers (PS). Importantly, for the most part the urban areas of the main cities (Gdańsk, Gdynia and Sopot) results show ground stability. Nevertheless, significant downward movements up to several mm/year, are locally noticed in the Vistula river delta - alluvial plain system located in the coastal zone east of Gdańsk as well as in the inland area west of the Gdańsk city. Indeed, the highest subsidence rates (-12 mm/year) was observed in the Gdańsk petroleum refinery constructed on alluvial sediments. Thus the anthropogenic loading and consolidation of the recent deposits can locally be an important factor causing ground subsidence