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EN
Geologists of the Polish Geological Institute carried out their professional activities abroad as part of geological expeditions, in teams of several people and on individual contracts, including as experts of the United Nations. In terms of the scope of work, most of their activities were focued on research on mineral resources, mapping, geochemistry, hydrogeology and geophysics, as well as on teaching of geology at the university level. The beginnings date back to the turn of the 1950s. It began with a geological expedition to Vietnam. Mongolia was the goal of subsequent expeditions on a much wider scale. The researches were conducted from the beginning of the 1960s until the end of the 1980s. The contracts, performed in groups of several people and individually, covered about 20 countries; most of them on the African continent. They focused primarily on the search for metal ore deposits, hard coal, and chemical and rock raw materials. PGI geologists also worked as UN experts in Benin, Burundi, Chad, Gabon, Haiti, India, Madagascar, Mauritania and Niger. The results of their work on various continents were the discoveries of numerous mineral deposits and the recognition of geological structure over an area of thousands of square kilometres.
EN
The Jawornik granitoids intrude, in vein-like form, a sequence of a polymetamorphic metavolcanic and metapelitic rocks of the Orlica-Śnieżnik Dome, Sudetes, Poland. This paper provides whole-rock geochemical data, sensitive high-resolution ion microprobe (SHRIMP) U-Pb zircon geochronological data as well as 40Ar-39Ar age determinations to constrain the genetic and temporal relationships of the different rock types forming these veins. Based on macroscopically visible features of the granitoids and their relationship with tectonic structures visible in the country rocks, four varieties of the Jawornik granitoids have been distinguished: amphibole- and biotite-bearing granites (HBG), biotite-bearing granites (BG), biotite- and muscovite-bearing granites (BMG) and muscovite-bearlng granites (MG). The Jawornik granitoids as a whole show a limited but significant variation in major element chemical composition, with SiO2 ranging from 65 to 76 wt.% (average 69.16 wt.%, n = 24). They are subalkalic, peraluminous and calc-alkaline [average A/CNK = 1.07, average (Na2O + K2O) = 7.75, average (Fe2O3t/(Fe2O3t + MgO) = 0.59]. Close inspection of their geochemical parameters showed that the samples investigated can be subdivided into two groups. The first group, the HBG, BG, and BMG varieties, comprising most of the granitoids in the Złoty Stok-Skrzynka Tectonic Zone, were formed by melting of greywackes or/and amphibolites. The MG, belonging to the second group, were formed by partial melting of a more felsic source. The HBG yielded a zircon U-Pb age of 351 ±1.3 Ma and well-defined Ar-399Ar plateau ages for hornblende (351.1 ±3.9 Ma) and coexisting biotite (349.6 ±3.8 Ma), indicating probably the oldest magmatic event in this region. Zircons from the MG, the youngest rock variety on the basis of their relationship with the tectonic structures in the host rocks yielded a U-Pb age of 336.3 ±2.4 Ma, though based on three points only. The biotites and muscovites from the BMG have Ar-39Ar plateau ages of 344.1 ±4.7 Ma and 344.6 ±3.8 Ma, respectively. These data, in combination with already published isotopic ages, suggest that the Jawornik granitoids intruded host rocks of the Orlica-Śnieżnik Dome in three stages, at ~350, ~344 and ~335 Ma.
EN
The research was conducted at the Kwiatków site, in the Koło Basin (Central Poland). It included a fragment of a low terrace and the valley floor of the Warta river valley. The archaeological investigation documented over 100 wells that archaeological material indicates are associated with the Przeworsk culture. Geomorphological, lithological and geochemical studies were carried out at the archaeological sites and their surroundings. Selected for the presentation were two wells whose fillings were carefully tested and subjected to geochemical and lithological analyses. The wells showed a slightly different content of artifacts, as well as differences in their grain-size distributions, the structure of their filling deposits, and their geochemistry. This allows us to conclude that the two wells were used differently, but also probably about a different course for how each well was filled after the end of its operation.
EN
Middle Miocene Badenian salt, occurring in the frontal zone of the Carpathian Overthrust (southern Poland), and the Upper Permian (Zechstein) bedded and diapir salt deposits, have been the subject of the research by PGI scientists. Many salt deposits were discovered by the PGI, but in particular, the greatest achievement related to the origin of salt deposits is the reconstruction of sedimentary environments and conditions based on detailed sedimentological and geochemical analyses.
EN
Borehole K-1 is an exploratory well that was drilled in the North Makassar Basin (West Sulawesi) in 2011. Gas chromatography (GC) and gas chromatography-mass chromatography (GC-MS) analyses have been conducted on extracts from well cuttings from the Paleogene to Neogene interval in order to investigate the characteristics of biomarkers present. Although the well was drilled with oil-based mud and gas chromatographic analysis reveals that the alkane fractions are heavily contaminated, detailed investigation of biomarkers in these rock extracts and comparison with biomarkers in the oil-based mud has revealed that, while there are hopane and sterane biomarkers in the mud, there are also a discrete set of biomarkers that are indigenous to the rocks. These include oleanane, bicadinanes, taraxastane and other higher-plant-derived triterpanes. The presence of these compounds in environments that range from bathyal to marginal marine and even to lacustrine, shows the extent of reworking of terrestrial material into aquatic settings in this region during the Paleogene and Neogene and provides further evidence of a predominance of terrestrial material, even in deep-marine settings, with little ‘in-situ’ material noted. These findings have important implications for the use of biomarkers as indicators of palaeoenvironment in both source rocks and oils.
EN
Magnetite, pyrite, pyrrhotite, chalcopyrite and sphalerite are the major minerals identified in the deposit, while ilmenlte, marcasite, tennantite, cubanite, arsenopyrite, galena, allanite, chevkinite, apatite, Bi-native, bismuthinite, electrum, native gold, and tellurides are the minor ones in the Iron Oxide Copper Gold (IOCG) Sin Quyen deposit. The REEs are hosted mostly by allanite, and the minor minerals by chevkinite, monazite, apatite and uraninite. Based on chemical analyses and Raman spectroscopy, two varieties of allanite have been documented: (1) with lower total REE contents of 13-19 wt.%, and (2) with higher contents of 20-23 wt.%. Uraninite from copper-iron massive ores is inhomogeneous in both optical properties and chemical composition. The concentrations of uranium and total rare earth element oxides (REOs) in the paragenetically earlier uraninite are 84.55-85.96% and 1.9-8.0% on average, respectively, whereas in paragenetically later uraninite, the U and ΣREE2O3 concentrations are 96.2-96.7% and 1.3-2.7% on average respectively. The thorium concentration in both the early and late uraninites is very low (0.21-0.22% and 0.2 % on average). These are the highest REE concentrations as compared with the known concentrations of these elements in uraninite. Electron microprobe “chemical” dating of the uraninite yielded an age of 500 ±33 Ma (n = 35) for the paragenetically early uraninite, and an age of 73 ±15 Ma (n = 6) for the paragenetically later ones. The minerals of the older age, which is interpreted as the primary ore mineralization stage, correspond in age with a range of deposits along the East Gondwana margin. The measured δ34S of sulphide minerals from -2.78 to +8.65%o suggests hydrothermal origin of fluid that was responsible for transportation and crystallization.
EN
The Upper Triassic shale of the Qadir Member of the Nayband Formation, East Central Iran has been analysed geochemically to evaluate provenance and palaeogeography. The Qadir Member in the Parvadeh Coal Mine section is 450 metres thick, and includes sandstone, shale, coal, siltstone, and fossiliferous limestone. XRD analysis of shale samples from the Qadir Member largely indicated the presence of illite and chlorite, with small amounts of kaolinite and montmorillonite. On binary and triangular diagrams the data suggests an intermediate igneous source rock for these shales. Plotting the geochemical data on binary diagrams also indicates the tectonic setting of an active continental margin, perhaps reflecting the Early Cimmerian tectonic event with Neothetys subduction under the Iran Plate, and collision of the Iran Plate with Turan during the Late Triassic. The Chemical Index of Alteration (CIA) and Plagioclase Index of Alteration (PIA) values for shale from the Qadir Member of Nayband Formation vary from 74.04 to 80.54 (average 78.02) and 84.31 to 91.85 (average 87.81), respectively, indicating moderate to high chemical alteration in the source area and suggesting a semi-humid climate duri ng deposition. The geochemical data and palaeogeographical models indicate that the Qadir Member shale was deposited on an active margin in a shoreline to transitional-marine setting.
EN
The uppermost part of the Khoy ophiolite includes submarine volcanic lavas. These rocks are found as two different types including basaltic pillow lavas and andesitic to andesitic basalt massive-sheet lavas known as the Qezil Dash unit. These last rocks host volcanogenic massive sulphide mineralisation (VMS). Concordant small lenticular massive sulphides associated with widespread stockworks, extensive wall rock alteration and simple mineralogical parageneses are characteristic of this mineralisation. The Qezil Dash lavas are characterized by HFSE depletion (such as in Nb, Zr, and Hf) and LILE enrichment, low Yb, Y and Ni contents and low Zr/Hf and Nb/Ta ratios. These rocks have low Ti contents and are of LKT type. These geochemical characteristics can be interpreted as indicating SSZ magmatism and suggesting that the Qezil Dash rocks belong to an early stage of island arc formation. Geochemically, this host rock is comparable with the Lasail unit, part of a volcanic sequence within the Oman ophiolite. In the Troodos and Oman ophiolites VMS mineralisation has occurred at the contacts of MOR-basalt and island arc tholeiite (IAT) lavas, so prospecting for VMS deposits in the Khoy area should be estabilished based on geochemical investigations of the volcanic rocks and recognition of their field boundaries.
EN
The Oligocene Arbat alkali intrusions of the Eastern Miandoab are located in the northwestern part of Iran and belong to the Urumieh-Dokhtar Magmatic Arc (UDMA). The intrusions show a ring structure with gabbro-monzogabbro-monzodiorite (mafic units) on the edges, with monzonite-monzosyenite-syenite (felsic units) gradually going towards the central parts. The textures in different rock types are cumulate, granular and laminated. The high values of (La/Sm)n and (La/Yb)n, contents of K, Rb and Cs (positive anomalies normalized on the basis of the primitive mantle), low concentrations of Hf, Nb, Zr and Ta (negative anomalies), and the changes in Th/Nb, Th/Ta, La/Nb and Ce/Pb ratios along with the geochemical and tectonic setting evidence exhibit a subduction-modified mantle origin for the formation of these rocks. Accordingly, the intrusions were formed between the Central Iran and the Arabian plates as a result of the partial melting of a mantle wedge at a syn-collision or post-collision arc-related environment. Our data suggested that, after the end of the oblique Neotethys subduction and during/after the continental collision, the break-off or rollback of the Neotethys slab beneath western Iran, in the Oligocene, might have occurred. Such a process led to the change in the geothermal gradient of the mantle wedge because of the subduction fluids, transtension, pressure reduction along the SE-trending lateral depth strike-slip fault zones in the upper part of the mantle wedge, decompression partial melting at the mantle, and the resulting formation of a mafic potassium-rich melt. The mafic magma was injected into crustal magma chambers; probably, the fractional crystaliization and partial contamination occurred with crustal components, forming the intermediate and felsic rocks in the intrusions. Geochemical evidence related to the variations in the ratios of Th/Yb, Ta/Yb, Rb/Y, and Nb/Y and Harker variation diagrams along with the spider diagrams confirmed fractional crystallization and partial FC (fractional crystallization) and AFC (assimilation and fractional crystallization) in the intrusions.
PL
Praca prezentuje wyniki szczegółowych badań składu chemicznego skał zubrowych dwu głównych wydzieleń litostratygraficznych w cyklotemowej sukcesji osadów polskiego cechsztynu: zubra brunatnego (Na3t; cyklotem PZ3) i zubra czerwonego (Na4t; cyklotem PZ4) oraz innych cechsztyńskich ogniw i formacji zubrowych wyróżnionych na obszarze Polski. Skały te opróbowano w 2 wysadach solnych (Kłodawa i Mogilno) oraz w profilach 7 otworów wiertniczych. Utwory Na3t w wysadzie Kłodawa cechuje wyższy udział halitu w porównaniu ze skałami Na4t, które zawierają więcej materiału terygenicznego (materiał detrytyczny i substancja ilasta) co wyraża się większą średnią zawartością SiO2, Al2O3, Fe2O3 i K2O oraz wzbogaceniem w Mn, Rb, Zn i Zr w porównaniu z osadami Na3t. Skały Na3t w obu wysadach (Kłodawa i Mogilno) charakteryzują się wyższą średnią zawartością CaO, MgO i Sr w porównaniu z wydzieleniem Na4t, przede wszystkim dzięki wyższemu udziałowi węglanów Ca i Mg (głównie magnezytu) i podrzędnie kalcytu i dolomitu. Zawartość bromu w profilach Na3t w obu wysadach jest wyższa niż w osadach Na4t i jest charakterystyczna dla pierwotnych chlorków wytrącanych z morskiej solanki. Podobną zawartość bromu stwierdzono tylko w niektórych partiach sukcesji Na4t. W niektórych skałach profili Na4t zarejestrowany udział bromu <40 ppm sugeruje, że są one mieszaniną pierwotnych i wtórnych chlorków, powstałych wskutek recyklingu (rozpuszczanie i ponowne wytrącanie) wcześniej osadzonych morskich soli. Zmiany zawartości bromu w profilach opisanego wyżej wydzielenia Na4t oraz w profilach skał zubrowych subcyklotemów cyklotemu PZ4, opróbowanych w wybranych otworach wiertniczych z obszaru Niżu Polskiego wskazują, że środowisko depozycji zubrów ewoluowało od basenu morskiego (dolna część profilu Na4t i osady subcyklotemów PZ4a do PZ4b) do kontynentalnego jeziora solnego (górna część sukcesji Na4t i osady subcyklotemów PZ4c do PZ4e), w którym następowała kumulacja materiału terygenicznego i chlorków wytrąconych głównie z wtórnych, recyklingowych solanek. Udział takich składników jak: SiO2, Al2O3, MgO, K2O i Fe2O3, Rb, Zn i Zr, związanych głównie z obecnością substancji ilastej i materiału detrytycznego jest wyższy w przypadku skał typu zubra bezteksturalnego i warstwowanego w porównaniu z solami kamiennymi i zailonym, warstwowanymi i bezteksturalnymi. Obecność Sr i CaO, związanych z węglanami i siarczanami, jest częściej wyższa w solach kamiennych warstwowanych, gdzie pojawiają się laminy ilasto-anhydrytowe.
EN
The paper presents results of detailed studies of chemical composition of zuber-like rocks of main two zuber lithostratigraphic units of the Polish Zechstein succession: the Brown Zuber (Na3t; PZ3 cyclothem) and the Red Zuber (Na4t; PZ4 cyclothem), as well as of other Zechstein zuber members and formations distinguished in Poland. These rocks were sampled from two salt domes (Kłodawa and Mogilno) and profiles of seven wells. Deposits of the Na3t unit in the Kłodawa dome have a higher content of halite compared with the Na4t unit. Deposits of the latter con - tain more terrigenous material (detrital and clay matter). They are characterized by higher average contents of SiO2 , Al2 O3 , Fe2 O3 and K2O and are enriched with Mn, Rb, Zn and Zr, compared with the Na3t succession. Rocks of the Na3t unit in both the Kłodawa and Mogilno domes are characterized by higher average contents of CaO, MgO and Sr than the deposits of the Na4t unit mainly due to their higher contents of Ca and Mg carbonates (with dominant magnesite) and, subordinately, of calcite and dolomite. Bromine content in the Na3t profiles of both domes is higher than in the Na4t deposits and it is characteristic for primary chlorides precipitated from marine brine. Such bromine concentration was found only in some parts of the Na4t succession. The bromine content <40 ppm, observed in some rocks of the Na4t profile, suggests that they are mixtures of primary and secondary chlorides, produced by recycling (dissolution and precipitation) of formerly accumulated marine salts. The bromine content changes, observed in the above-described Na4t unit profiles, as well as in the zuber profiles of the PZ4 subcyclo - thems, show that depositional environment of the zuber deposits evolved from a marine basin (in the lower part of the Na4t profile and in deposits of the PZ4a and PZ4b subcyclothems) to continental saline lakes (in the upper part of the Na4t succession and in deposits of the PZ4c to PZ4e subcyclothems), which trapped a terrigenous material an d chlorides precipitated mainly from secondary (recycled) brine s. The contents of such components as SiO2, Al2O3 , MgO, K2O, Fe2O3 , Rb, Zn and Zr, highly influenced by the content of clay matter and detrital material, are significantly higher in the structureless and layered zuber types, compared with the textural equivalents of clayey and rock salts. The contents of Sr and CaO, connected with carbonate and sulphate admixture, are commonly higher in the layered rock salts with frequent clay-anhydrite laminae.
EN
To optimize exploration for new hydrocarbon accumulations in the Polish Outer Carpathians, it is necessary to concentrate attention on identification of hydrocarbon accumulations of the “shale-gas” type. Results of recently completed analysis suggested new such possible targets in the Magura Basin, preserved in the Outer Carpathian Magura Nappe. Analysis of the preliminary results of paleoenvironmental and geochemical studies of these shales is the subject of this paper. Micropaleontological and geochemical study was conducted on the 300 m thick Świątkowa Member, the uppermost part of the Ropianka Formation located in the external, northernmost Siary Zone. This member is composed of thin- and medium-bedded sandstones interbedded by green, brown, black and dark-gray shales. Poor and changeable oxygenation is reflected in the composition of foraminiferal assemblages. A negative correlation between the TOC content and numbers and diversity of foraminifera is observed. The paleogeographic position and paleoenvironment assessment indicates that the Siary Zone fulfills certain conditions for organic productivity and preservation during the deposition of the Ropianka Formation.
EN
The Ahmadabad hematite/barite deposit is located to the northeast of the city of Semnan, Iran. Geostructurally, this deposit lies between the Alborz and the Central Iran zones in the Semnan Subzone. Hematite-barite mineralisation occurs in the form of a vein along a local fault within Eocene volcanic host rocks. The Ahmadabad deposit has a simple mineralogy, of which hematite and barite are the main constituents, followed by pyrite and Fe-oxyhydroxides such as limonite and goethite. Based on textural relationships between the above-mentioned principal minerals, it could be deduced that there are three hydrothermal mineralisation stages in which pyrite, hematite and barite with primary open space filling textures formed under different hydrothermal conditions. Subsequently, in the supergene stage, goethite and limonite minerals with secondary replacement textures formed under oxidation surficial conditions. Microthermometric studies on barite samples show that homogenisation temperatures (TH) for primary fluid inclusions range from 142 to 256°C with a temperature peak between 200 and 220°C. Salinities vary from 3.62 to 16.70 NaCl wt% with two different peaks, including one of 6 to 8 NaCl wt% and another of 12 to 14 NaCl wt%. This indicates that two different hydrothermal waters, including basinal and sea waters, could have been involved in barite mineralisation. The geochemistry of the major and trace elements in the samples studied indicate a hydrothermal origin for hematite and barite mineralisation. Moreover, the Fe/Mn ratio (>10) and plots of hematite samples of Ahmadabad ores on Al-Fe-Mn, Fe-Mn-(Ni+Co+ Cu)×10, Fe-Mn-SiX2 and MnO/TiO2 – Fe2O3/TiO2 diagrams indicate that hematite mineralisation in the Ahmadabad deposit occurred under hydrothermal conditions. Furthermore, Ba and Sr enrichment, along with Pb, Zn, Hg, Cu and Sb depletion, in the barite samples of Ahmadabad ores are indicative of a low temperature hydrothermal origin for the deposit. A comparison of the ratios of LaN/YbN, CeN/YbN, TbN/LaN, SmN/NdN and parameters of Ce/Ce* and La/La* anomalies of the hematite, barite, host volcanic rocks and quartz latite samples to each other elucidate two important points: 1) the barite could have originated from volcanic host rocks, 2) the hematite could have originated from a quartz latite lithological unit. The chondrite normalised REE patterns of samples of hematite barite, volcanic host rocks and quartz latite imply that two different hydrothermal fluids could be proposed for hematite and barite mineralisation. The comparison between chondrite normalised REE patterns of Ahmadabad barite with oceanic origin barite and low temperature hydrothermal barite shows close similarities to the low temperature hydrothermal barite deposits.
EN
Combined petrographic and geochemical data of the siliciclastic sedimentary rocks from the Shemshak Group in the northeastern Alborz Mountains, north of Iran are described, together with their implications for palaeoweathering, their provenance, and tectonic setting. Based on field observations and modal composition, the sandstones are classified as litharenites. The chemical index of alteration (CIA) indicated that the source terrains underwent a moderate intensity of chemical weathering. The index of chemical variation (ICV) values indicated that the Shemshak Group rocks were immature and related to a source area with an active tectonic regime. Major, trace and rare earth element (REE) data suggested the domination of mixed sedimentary (recycled) and igneous rocks in the source area of the Shemshak Group. Petrographic and geochemical characteristics of Shemshak Group rocks suggest an active continental margin (ACM), which corresponds to the collision of the Iran plate with the Turan plate.
EN
Mercury geochemistry is emerging recently as a hot topic in chemostratigraphical and facies research, owing to the diagnostic character of Hg enrichments as a proxy of volcanic activity (crucial in the context of assumed causal links between volcanic cataclysms and mass extinctions). Thus, as a prerequisite to such far-reaching interpretations, reliable analytical determinations of Hg concentrations are necessary. In conventionally performed analyses in sedimentary geochemistry, Inductively Coupled Plasma – Mass Spectrometry (ICP-MS) is usually applied, as an analytical standard for trace elements, including Hg. However, with a detection limit (DL) of 10 ppb, such measured values have been questioned as a conclusive geochemical indicator of Hg anomalies, and, instead, far more accurate techniques, such as Atomic Absorption Spectrometry (AAS; DL = 0.2 ppb), are requested. As a preliminary test of this view, we present comparative analysis of 91 samples from three sections encompassing the key Frasnian-Famennian and Famennian-Tournaisian boundary intervals in Morocco (Lahmida), Germany (Kahlleite) and Uzbekistan (Novchomok), for which Hg concentrations were determined by both methods in the same samples. Despite some differences, especially at low Hg concentrations, both analytical methods reveal the same 12 extraordinarily enriched samples in excess of 1 ppm (with one exception, the determination error is <20%), as well as similar overall chemostratigraphic patterns characterized by a few prominent Hg spikes, with a top value of 5.8 ppm. The Hg concentrations determined by ICP-MS and AAS are significantly correlated, as high as r = 0.98 (Novchomok), even if the first method reveals a general tendency toward slightly heightened values (by ~15 to 30% for medians). Therefore, ICP-MS results can conclusively be used in mercury chemostratigraphy in order to recognize extraordinary volcanic (or other) signals, at least in the Devonian geological record. False Hg anomalies were not generated by these conventional ICP-MS determinations.
PL
Surowce krytyczne charakteryzują się dużym znaczeniem gospodarczym, ale też jednocześnie dużym ryzykiem niedoboru dostaw. Obecnie podejmowane są działania mające na celu poprawę stanu wiedzy na ich temat, co ma doprowadzić do utworzenia w 2020 roku ogólnoeuropejskiej bazy wiedzy o możliwościach ich pozyskiwania. W grupie wyróżnionych 27 surowców krytycznych znaczną część stanowią pierwiastki krytyczne. Obok źródeł naturalnych pierwiastki krytyczne mogą także występować w materiałach odpadowych, w tym w żużlach po hutnictwie rud Zn-Pb. Przeprowadzone badania wykazały, że w ich składzie chemicznym w największych ilościach występują: W, Co, Ce, Y, La, Sc, w śladowych ilościach oznaczono: Dy, Pd, Pt, Ir. Żaden z tych pierwiastków nie tworzy w analizowanych żużlach własnych faz krystalicznych; występują one w stanie rozproszonym w substancji amorficznej lub tworzą podstawienia w strukturze wewnętrznej innych faz. Stwierdzono, że precyzyjne oznaczenie zawartości danego pierwiastka oraz określenie form jego występowania wymusza konieczność prowadzenia kompleksowych analiz w oparciu o kilka wzajemnie uzupełniających się metod.
EN
Critical raw materials are characterized by a high economic importance, but also by a high risk of shortage of supplies. Currently, some actions of improving a state of knowledge about them are taken. In 2020, it should be lead to the creation of a pan-European knowledge database about the possibilities of their obtaining. In the group of distinguished 27 critical raw materials, critical elements are a significant part. Apart from natural sources, critical elements may also appear in waste materials, including slags from the Zn-Pb ore industry. Researches showed that in their chemical composition W, Co, Ce, Y, La, Sc are concentrated in the largest amounts. In trace amounts: Dy, Pd, Pt, Ir were also noticed. In the analyzed slags none of these elements creates their own crystalline phases; they are dispersed in an amorphous substance or they form substitutions in the internal structure of other phases. Researches have shown that the precise determination of content of a given element and the determination of its occurrence, require the necessity of conducting comprehensive analyzes based on several complementary methods.
EN
In the Polish sector of the Magura Nappe have long been known and exploited carbonate mineral waters, saturated with carbon dioxide, known as the “shchava (szczawa)”. These waters occur mainly in the Krynica Subunit of the Magura Nappe, between the Dunajec and Poprad rivers, close to the Pieniny Klippen Belt (PKB). The origin of these waters is still not clear, this applies to both “volcanic” and “metamorphic” hypotheses. Bearing in mind the case found in the Szczawa tectonic window and our geological and geochemical studies we suggest that the origin of the carbon dioxide may be linked with the thermal/pressure alteration of organic matter of the Oligocene deposits from the Grybów Unit. These deposits, exposed in several tectonic windows of the Magura Nappe, are characterized by the presence of highly matured organic matter – the origin of the hydrocarbon accumulations. This is supported by the present-day state of organic geochemistry studies of the Carpathian oil and gas bed rocks. In our opinion origin of the carbon-dioxide was related to the southern, deep buried periphery of the Carpathian Oil and Gas Province. The present day distribution of the carbonated mineral water springs has been related to the post-orogenic uplift and erosion of the Outer (flysch) Carpathians.
EN
Pale brownish celestine-rich salt rocks were found near the Franciuszek Müller gallery, in the chambers of the 3rd level in the Wieliczka Salt Mine. The complex of rock salts subjected to exploration occurred within a large seam approximately 15 m thick. Detailed research revealed that the salt has the form of a block incorporated within the gray salts body and being similar to other blocks of green salts, well known in the upper part of the deposit. A characteristic petrographical feature of the pale brown rock salt owed to the presence of celestine (SrSO 4 ). That strontium mineral was re-examined, using X-ray powder data, and scanning microscope observations, with EDS analysis. The investigated rock salts exhibited a mineral association of halite (main component), anhydrite, celestine, calcite, gypsum, clay materials, iron compounds and a small amount of bitumen. Interrigenous sediments and the insoluble part of salt occurred higher content of strontium that in halite. Celestine crystals were observed in two forms: elongated platy crystals, forming fan-shaped aggregates and granular aggregates, strongly associated with anhydrite. On carbonate and sulphate strontium usually appearing as needle shaped aggregates of celestine. No barium minerals were observed. The development and paragenesis of celestine suggested a post-sedimentary origin of these rocks that ought to be connected with diagenetic processes. An important observation that confirmed that thesis was the transformation of fine crystalline anhydrite into platy crystals, recrystallization and primary accumulation of strontium, as a result of evaporation processes.
EN
The Baltic Sea is not typically considered as an area affected by tsunamis. However, during the Late Pleistocene and Holocene several tsunami events have been interpreted from the sedimentary record, mainly in Sweden and Estonia. Furthermore, on the southern coast of the Baltic Sea, there are historical accounts of catastrophical marine floodings called “der Seebär” (“the Sea Bear”). Their descriptions reveal many features typical for tsunami, but their genesis remained unknown and sedimentary evidence for such events has not been found. Here we provide evidence of sandy event layers from the area of Rogowo, NW Poland – the area of historical catastrophic storms as well as “der Seebär” events. The study area is a low-lying coastal plain with an average elevation of –0.5 to +0.5 m a.s.l., protected from the open sea by beach and coastal dune systems up to 5 m high. Sedimentological, micropalaeontological and geochemical analyses along with AMS 14C dating were applied to sedimentary successions seen in 5 major trenches and 198 sediment cores up to 1.5 m long. Two sandy layers were identified in the peat deposits that developed on the plain during the last ~2000 years. They reveal a number of typical features of tsunami deposits (significant lateral extent and thickness, rip-up clasts, chemical and micropalaeontological evidence of marine origin), however, 14C dating along with the historical accounts revealed that the major layer, extending at least 1.2 km from the modern coasts, was probably deposited by arguably the largest storm surge during the last 2000 years, which took place in 1497 AD. These storm deposits were likely formed during inundation of the low-lying coastal plain after major breaching of coastal dunes resulting in tsunami – like flow pattern and thus similar sedimentological effects. A discontinuous sand layer of younger age (18th century) and sharing similar properties to the previous one may be related to “der Seebär” event or another storm surge. The study revealed that the southern Baltic Sea coast may be affected by much greater coastal flooding than known from more recent accounts and observations. Thus, the presented geological record should be taken as an example of a worst-case scenario in coastal zone risk assessment from natural hazards. These events left sedimentary deposits that resemble tsunami deposits. It is likely that, in similar settings where storm surges cause unidirectional inundation of a coastal plain, it may not be possible to establish whether the resulting deposits were laid down from storms or tsunamis.
EN
During the Paleogene, the area of the northern Tethys was controlled by a turbidity system stimulated by diastrophic and geodynamic processes. These factors contributed to the dispersion and rapid oxygenation of organic debris. Its accumulation was a consequence of stagnant bottom water conditions that periodically occurred in the basin. In these periods, intense decomposition intensified by hydrothermal and diagenetic processes was associated with oxygen consumption and the release of greenhouse gases, which led to hypoxia and acidification. These phenomena intensified by thermal and density stratification had a major impact on the structure, evolution and distribution of biota. Stress associated with rapidly changing conditions induced by sedimentary process and upwelling resulted in the dominance of forms that colonized most sediments (Glomospira, Ammodiscus, Recurvoides, Rzehakina) and surface waters (Guembelitria, Chiloguembelina, Globanomalina, Globigerina, Cassigerinella, Catapsydrax). At the time, foraminifera were limited to low-diversified eutrophic assemblages or were mainly replaced by siliceous phytoplankton (radiolarians and diatoms). Geochemical data confirm that environmental crises in the Paleogene basin took place under changing thermal conditions that reflect global events (KTBE, PTME, EEOC and TTE). Thermal stress favouring the formation of certain minerals or rocks occasionally occurred during the Paleocene to Eocene (siderite, phosphates) and dominated in the Early Oligocene (silica).
EN
Detrital chromian spinels in sedimentary rocks provide much information concerning the tectonics of their parental ultrabasic rocks. Chromian spinels occurring in the Eocene to Oligocene depos its from the Magura Nappe were exam i ned to provide some constraints on the history of the Magura Basin. The Magura Nappe is a part of the Flysch Belt belonging to the External Western Carpathians. The Magura Nappe is separated by a narrow zone associated with the Pieniny Klippen Belt and is divided into three principal tectono-lithofacies units (from the S to N): the Krynica, Bystrica and Rača units. Cr-spinel is a common accessory mineral (2.3-5.9 vol% of heavy mineral spectra) in the siliciclastic rocks of the Rača and Krynica units. In terms of texture and chemical composition, two types of Cr-spinels were recognized: unaltered and altered. Unaltered spinels were found to contain silicate inclusions such as chromio-pargasite, enstatite, diopside, pargasite, plagioclase and olivine (forsterite). The chromian spinels show wide variations in compositional parameters such as Cr# (0.3-0.7), Mg# (0.3-0.7), TiO2 (<0.03-1.9 wt.%) and Fe2+/Fe3+ (2.5-13) whereas the differences between the Rača and Krynica units are in- significant. These parameters suggest a peridotitic and volcanic origin of the spinels, respectively. The ophiolite source consisting of harzburgitic mantle peridotites was developed mainly in a supra-subduction zone setting; volcanic spinels indicate an origin in mid-ocean ridge basalts, back-arc basin basalts and sporadically in ocean-island basalts. Concerning their geochem i cal features, we propose that during the Eocene to Early Oligocene, the ophiolitic detritus in the eastern part of the Magura Basin deposits may have been derived from a source area located in the Fore-Marmarosh Suture Zone (Eastern Carpathians) that is considered an equivalent of the Black Flysch and Ceahlau units. Some Cr-spinels found in the Eocene sedimentary successions may have resedimented from older Late Cretaceous-Paleocene formations of the Magura Unit, which are considered as reworked sedimentary material from the Pieniny Klippen Belt.
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