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EN
In 2009, on the initiative of PT Halmahera Perkasa the “Jayapura” exploration project was carried out in Indonesia. As part of this project, exploration of the sea bottom in the northern coast of New Guinea was carried out over a distance of ~45 km. The suction dredge collected 59 samples of loose sediments from the shelf bottom surface of the Carolinian Sea (to a depth of 60 m below the sea-floor). The extracted samples are usually poorly and moderately sorted sands (5 samples), medium-grained sands (21 samples), and fine-grained sands (33 samples). The sand composition shows, among others, a wide spectrum of heavy minerals of ultra-mafic (Cr-garnet, chromium spinel, Mg-olivine) and metamorphic (epidote, clinochlore, amphibole, titanite) origin. The content of heavy minerals in the sediments is up to 54.77 wt.%. It was found that the source of heavy fraction in the eastern and western parts of the coast is the rock of the ophiolite series building the Cyclops Mountains Massif. The mineral composition of sediments from the central coastal zone corresponds to the types of rocks building the metamorphic core of the Cyclops Mountains (amphibolite, gneisses, andesite). Three mineral-geochemical subprovinces were determined on the basis of analyses of heavy mineral decomposition and chemical analyses of sediments. Shelf sediment from the eastern part of the coast is characterized by an increased content of strategic metals (Ni up to 3560, W up to 3130 and Co up to 142 ppm). In the central zone, the V content increases up to 244 ppm and the Ag content up to 5 ppm. In the shelf sediments there is a strong depletion in the REE.
EN
Lithological and palynological studies of Paleogene siliciclastic deposits from the Yantarny P-1 borehole located on the western coast of the Sambian Peninsula (Kaliningrad region, Russia) show that the succession is characterized by numerous sedimentary discontinuities related to lithification horizons and erosional surfaces. Sedimentary gaps are emphasised by hardgrounds. Palynological data suggest the Selandian-Priabonian age of the succession and indicate a number of significant stratigraphic gaps. An important change in heavy mineral composition is recognized between the Paleocene and Eocene deposits in the area studied. A significant number of reworked Cretaceous microfossils is observed in the Selandian part of the succession studied.
PL
W skałach miocenu zapadliska przedkarpackiego zauważono zjawisko zawyżania pomiarów promieniotwórczości naturalnej rejestrowanych w otworze wiertniczym dla mułowców. To zjawisko powoduje problemy w rozróżnianiu na podstawie profilowania naturalnej promieniotwórczości tych skał od iłowców, które charakteryzują się gorszymi parametrami petrofizycznymi. W niniejszej pracy badano kolejne możliwe źródło podwyższonej radioaktywności skał mułowcowych, to jest zawartość minerałów ciężkich, które wykazują tendencję do gromadzenia pierwiastków promieniotwórczych – uranu i toru. Minerały ciężkie, należące do grupy minerałów akcesorycznych, takie jak cyrkon, apatyt, monacyt, rutyl, granat i tytanit, charakteryzują się podwyższoną promieniotwórczością ze względu na podstawienia w sieci krystalicznej U i Th. Na testowych próbkach wykonano pomiar naturalnej promieniotwórczości metodą spektrometrii gamma, przy wykorzystaniu aparatu RT-50 firmy Georadis. Następnie z próbek skał wydzielono minerały ciężkie, przy użyciu cieczy ciężkiej, uprzednio rozdzielając próbki na frakcje ziarnowe, w celu ułatwienia separacji frakcji ciężkiej. Poszczególne frakcje ziarnowe pozbawione minerałów ciężkich złączono z powrotem i wykonano ponowny pomiar zawartości uranu, toru i potasu. Wykonano także obserwacje mikroskopowe w celu jakościowej analizy składu mineralogicznego wydzielonej frakcji ciężkiej. W badanych próbkach zidentyfikowano między innymi ziarna cyrkonu, turmalinu, granatu, rutylu, apatytu, chlorytu czy tytanitu. Przeprowadzone wyniki pomiarów naturalnej promieniotwórczości, przed i po wydzieleniu minerałów ciężkich, nie dają jednoznacznej odpowiedzi na postawiony problem zawyżonych wskazań sondy gamma. Konieczne jest zwiększenie ilości analizowanych próbek. Zaobserwowano trend spadku ilości U i Th w próbkach, z których wydzielono frakcję ciężką. Jednak zmiany promieniotwórczości są na tyle niewielkie, że nie pozwalają na wyciągnięcie ostatecznych wniosków. Dodatkowe analizy są potrzebne, aby ocenić wpływ pozostałych źródeł uranu i toru w badanych skałach, takie jak zawartość materii organicznej czy udział toru we frakcji ilastej.
EN
In the Miocene rocks of the Carpathian Foredeep, the occurrence of overestimating the measurements of natural radioactivity logs for mudstones was noticed. This phenomenon causes problems with recognition on the basis of natural radioactivity profiling of these rocks from claystones, characterized by inferior petrophysical parameters. In this study, another possible source of increased radioactivity of mudstone rocks, i.e. the content of heavy minerals that tend to accumulate radioactive elements - uranium and thorium - was investigated. Heavy minerals, belonging to the accessory minerals, such as zircon, apatite, monazite, rutile, garnet and titanite, are characterized by increased radioactivity due to substitutions of U and Th in the crystal lattice. Natural radioactivity of the test samples was measured using the gamma spectrometry method with the RT-50 device from the Georadis company. The heavy minerals were then removed from the rock samples using a heavy liquid, previously separating the samples into grain fractions to facilitate the separation of the heavy fraction. The individual grain fractions deprived of heavy minerals were put back together and the uranium, thorium (and potassium) content was remeasured. Microscopic observations were also made to qualitatively analyze the mineralogical structure of the separated heavy fraction. In the tested samples, among others: zircon, tourmaline, garnet, rutile, apatite, chlorite or titanite grains were identified. The results of the measurements of natural radioactivity, before and after the separation of heavy minerals, do not give a clear answer to the problem of excessive indications of the gamma logs. It is necessary to increase the number of analyzed samples. The trend of decreasing amounts of U and Th in the samples from which the heavy fraction was isolated was observed. However, changes in radioactivity are so small that they do not allow to draw final conclusions. Additional analyzes are needed to assess the impact of other sources of uranium and thorium in analyzed rocks, such as the content of organic matter or Th content in clays.
EN
The present study discusses results of heavy mineral analyses and radioactivity of beach sediments of Lake Peipsi. Such analyses are commonly done globally, but had not yet been conducted for the fourth largest lake in Europe. The average heavy mineral content in Lake Peipsi beach sediments along the northern and western coast is higher than usual for Estonian coastal and Quaternary sediments. Concomitantly, elevated radioactivity levels have been measured in several places, with the highest concentrations observed at Alajõe (1885.5 Bq/kg), which is over five times more than the recommended limit. The aim of the present study is to find sites with higher radioactivity levels, because the northern coast of Lake Peipsi is a well-known recreational area.
EN
Deposits formed between the Neogene/Pleistocene transition and into the Early Pleistocene have been studied, mainly on the basis of drillings and at rare, small outcrops in the lowland part of Polish territory. At the Bełchatów lignite mine (Kleszczów Graben, central Poland), one of the largest opencast pits in Europe, strata of this age have long been exposed in extensive outcrops. The present paper is based on our field studies and laboratory analyses, as well as on research data presented by other authors. For that reason, it can be seen as an overview of current knowledge of lowermost Pleistocene deposits at Bełchatów, where exploitation of the Quaternary overburden has just been completed. The results of cartographic work, sedimentological, mineralogical and palynological analyses as well as assessment of sand grain morphology have been considered. All of these studies have allowed the distinction of three Lower Pleistocene series, i.e., the Łękińsko, Faustynów and Krzaki series. These were laid down in fluvial environments between the end of the Pliocene up to the advance of the first Scandinavian ice sheet on central Poland. The following environmental features have been interpreted: phases of river incision and aggradation, changes of river channel patterns, source sediments for alluvia, rates of aeolian supply to rivers and roles of fluvial systems in morphological and geological development of the area. The two older series studied, i.e., Łękińsko and Faustynów, share common characteristics. They were formed by sinuous rivers in boreal forest and open forest environments. The Neogene substratum was the source of the alluvium. The younger series (Krzaki) formed mainly in a braided river setting, under conditions of progressive climatic cooling. Over time, a gradual increase of aeolian supply to the fluvial system can be noted; initially, silt and sand were laid down, followed by sand only during cold desert conditions. These fluvio-periglacial conditions are identified in the foreground of the advance of the oldest ice sheet into this part of central Poland. The series studied have been compared with other fluvial successions which accumulated in the Kleszczów Graben during subsequent glaciations so as to document general changes in fluvial systems as reactions to climatic evolution. Thus, a palaeoenvironmental scenario has emerged which could be considered to be characteristic of central Poland during the Early Pleistocene.
EN
The origin and age of cave deposits, as well as palaeogeographical changes in the Bystrej catchment during the last ca. 250 ka, were reconstructed in Magurska, Kasprowa Niżnia, Goryczkowa, Kalacka and Bystrej caves (the Bystrej Valley). The reconstruction is based on the study of corrosive forms, heavy mineral analyses and U-series dating of speleothems. Two generations of palaeoflows were distinguished by observations of scallops and heavy mineral analyses. In the older stage, now abandoned caves drained massifs surrounding the Bystrej Valley and part of an adjacent valley. The direction of palaeoflow changed as a result of the water capture after Kasprowa Niżnia Cave came into being. In the later stages, the evolution of cave systems was controlled by glaciation-deglaciation cycles. Probably at this time, some caves located in the lowest parts of the massifs also started to be formed. U-series speleothem dating allows the determination of five phases of speleothem deposition: ca. 220–150 ka, ca. 135–105 ka, ca. 95–70 ka, ca. 40–23 ka and during the Holocene.
PL
W niniejszej pracy przedstawiono sposoby wykorzystania minerałów ciężkich w geologii naftowej oraz zaprezentowano metody wydzielania minerałów ciężkich, kluczowe dla wykonania końcowej analizy. Zaprezentowano również wewnętrzną procedurę wydzielania minerałów ciężkich opracowaną w Zakładzie Geofizyki Wiertniczej INiG – PIB, która jest dostosowana do niewielkich próbek (< 1 kg, < 0,5 kg) rdzeni wiertniczych. Opracowana metodyka została z powodzeniem wykorzystana do uzyskania frakcji ciężkiej z próbek piaskowców i będzie wykorzystana do analizy proweniencji materiału detrytycznego tych skał.
EN
This paper presents application of heavy minerals analysis in petroleum geology and methods of separation of heavy minerals that are crucial for the final analysis. An in-house procedure for separation of heavy minerals developed at the Well Logging Department of Oil and Gas Institute – NRI was presented. The procedure was adapted to small samples (< 1 kg, < 0.5 kg) of drill cores. The developed methodology was successfully used to obtain a heavy fraction of the sandstones samples. Separated minerals will be used to analyse the provenance of detrital material of these rocks.
EN
The carried out pilot work on the concentration of rare earth elements (REE) in the Baltic marine sands from the Odra and Słupsk Banks showed that in some places their accumulations are quite interesting in terms of the placer deposits and may be the subject of an interesting prospecting project. The results of ICP-MS and electron microprobe (CAMECA SX-100) investigation confirm the close relationship of REE concentration to heavy minerals content in the sediments of marine sands. It is indicated, in addition to monazite, as a primary mineral carrier of rare earth elements. The vast preponderance of light REE is noted in the samples of heavy mineral concentrates from the Odra and Słupsk Banks as well as in the beach sand sample from the Hel Peninsula. The highest concentrations are achieved mainly by cerium and almost two times less by lanthanum. The total REE in the most interesting considered samples range from c.a. 0.14% (trench on the beach) to 0.9% (heavy minerals concentrate from the Odra Bank). The high contents of REE are accompanied by a high concentration of Th (900–150 ppm). Neodymium (0.1–0.17% Nd), whose presence is associated with the presence of pyrochlore and Nb-rutile also appears in the heavy minerals concentrate samples. It is necessary to systematically identify heavy minerals resources in the Baltic sands. More detailed research should cover the prospective areas situated to the North-East from the documented placer fields of the Odra Bank, as well as tentatively identified areas of the Słupsk Bank and submarine paleo-slope of the Hel Peninsula.
PL
Przeprowadzono pilotażowe prace nad koncentracją REE w piaskach bałtyckich za pomocą metodyki ICP-MS oraz mikrosondy elektronicznej (CAMECA SX-100). Analizy chemiczne składu jakościowego i ilościowego pierwiastków ziem rzadkich w próbkach piasków z koncentratów minerałów ciężkich z Ławicy Odrzanej oraz z Ławicy Słupskiej jak również z wkopu na plaży na Półwyspie Helskim (16,6 km plaży wybrzeża) osiągają zawartości REE, które mogą być interesujące pod względem surowcowym. Wyniki oznaczeń potwierdzają zależność koncentracji REE od procentowej zawartości minerałów ciężkich w osadach piasków morskich. Wskazują ponadto na monacyt jako główny wśród minerałów nośnik REE. W zbadanych próbkach koncentratów minerałów ciężkich oraz w próbce z Półwyspu Helskiego jest zdecydowana przewaga LREE. Najwyższe koncentracje osiąga głównie cer, a prawie dwukrotnie niższe lantan. Suma REE w wyżej wymienionych najciekawszych pod względem zawartości REE próbkach mieści się w zakresie od około 0,14% (wkop na plaży) do około 0,9% (koncentrat z Ławicy Odrzanej). Wysokiej koncentracji REE towarzyszy wysoka zawartość Th (900–150 ppm). W próbkach koncentratu minerałów ciężkich pojawia się również neodym (0,1–0,17% Nd), którego obecność jest związana z pojawianiem się pirochloru oraz Nb-rutylu. Konieczne jest systematyczne rozpoznanie zasobów minerałów ciężkich w piaskach bałtyckich. Dokładniejszymi badaniami powinny być objęte obszary perspektywiczne położone na północny wschód od pól złożowych objętych dokumentacją zasobową „Ławica Odrzana”, wstępnie rozpoznane obszary na Ławicy Słupskiej oraz podwodny skłon (paleo-mierzeja) Półwyspu Helskiego.
EN
Detrital heavy minerals separated from the Malcov Fm. deposits (Magura Nappe) indicate their source rocks and areas. The heavy mineral assemblages predominantly consist of garnet, zircon, tourmaline, rutile and Cr-spinel. EPMA analyses reveal a few groups of garnets: zoned and unzoned Grs almandines, Prp-Sps almandines, unzoned Prp almandines, almandines, Sps almandines and rare zoned spessartine grains (~85 mol% Sps). The garnet composition indicates that gneisses, mica schists, amphibolites and granites were their main source rocks, but low-grade metapelites with Mn mineralisation probably contributed as well. The detrital dravitic tourmalines were mostly derived from paragneisses and mica schists. Cr-spinel indicates a volcanic source. Based on heavy mineral assemblages, coupled with palaeoflow analysis, we conclude that the Marmarosh Massif and Fore-Marmarosh Suture are the most probable source areas. Aditionally, the Malcov sedimentary basin was supplied by material from the crystalline complexes of the Tisza Mega-Unit and Pieniny Klippen Belt (PKB). The bulk of the clastic deposits comprise classical turbidites. These lithofacies were deposited from either turbidity currents or from concentrated density flows. The palaeoflow record is varied and highlights the contribution of sedimentary material from several directions and/or diversion of gravity currents from the main flow direction (SE–NW). The marginal parts of the Malcov sub-basins were formed of deformed and uplifted older formations of surrounding units of the Magura Nappe and PKB (submerged ridges). Older (Late Cretaceous to Eocene) flysch sediments may have been redeposited from these ridges to neighbouring sub-basins in a transverse direction (NE–SW).
EN
During the Pleistocene the Scandinavian ice sheet drained huge quantities of sediment-laden meltwaters. These meltwaters supplied ice-marginal valleys that formed parallel to the front of the ice sheet. Not without significance was the supply of ice-marginal valleys from extraglacial rivers in the south. Moreover, periglacial conditions during and after sedimentation in ice-marginal valleys, the morphology of valley bedrocks, and erosion of older sediments played important roles in the depositional scenarios, and in the mineralogical composition of the sediments. The mechanisms that controlled the supply and deposition in ice-marginal valleys were analysed on the basis of a Pleistocene ice-marginal valley that was supplied by northern and southern source areas in the immediate vicinity. Investigations were conducted in one of the largest ice-marginal valleys of the Polish-German lowlands, i.e., the Toruń-Eberswalde ice-marginal valley, in sandurs (Drawa and Gwda) supplied sediments and waters from the north into this valley, and on extraglacial river terraces (pre-Noteć and pre-Warta rivers), formed simultaneously with the sandurs and ice-marginal valley (Pomeranian phase of Weichselian glaciation) supplied sediments and waters from the south into this valley. A much debated question is how similar, or different, depositional processes and sediments were that contributed to the formation of the Toruń-Eberswalde ice-marginal valley, and whether or not it is possible to differentiate mostly rapidly aggraded sandur sediments from ice-marginal valley sediments. Another question addresses the contribution of extraglacial feeding of the Toruń-Eberswalde ice-marginal valley. These matters were addressed by a wide range of analyses: sediment texture and structure, architectural elements of sediments, frequency of sedimentary successions, heavy-mineral analysis (both transparent and opaque heavy minerals), analysis of rounding and frosting of quartz grains, and palaeohydrological calculations. Additionally, a statistical analysis was used. The specific depositional conditions of distribution of sediments in ice-marginal valley allow to distinguish new environment of ice-marginal valley braided river. The spectrum of depositional conditions in the Toruń-Eberswalde ice-marginal valley and their specific palaeohydraulic parameters allow to distinguish three coexisting zones in the ice-marginal valley braided-river system: (1) deep gravel-bed braided channel zone with extensive scours, (2) deep sand-bed braided channel zone with transverse bars, and (3) marginal sand-bed and gravel-bed braided channel zone with diamicton and breccia deposition, which were characterised in detail. Some of the results have been published previously, which is why they are discussed in the present paper within the context of new data.
EN
Sandstones and conglomerates, which northwards of Brno agglomeration build a hill (ridge) named Babí lom are strongly diagenezed (anchi-metamorphozed) and tectonically deformed. Their regional distribution and stratigraphic position between the Cambrian(?) clastics and Upper Devonian limestones, as well as their appearance meant that they age is considering as Middle Devonian. They are distinguished as the so-called „Basal Devonian Clastics“. Almost all primary sedimentary features are well preserved and distinct. In the metasediments of the Babí lom hill were distinguished both the facies and structures typical of alluvial fans and rivers. Among others they are channel lags with imbricated grains, cross beddings and debrites. Within sedimentary association was established the way-up direction what clearly evidences a coarsening upwards sequence. Assuming the lack of rotation of series of sediments in the X-Y plane, the palaeotrasport was toward the north while major supply with material was from the east.
PL
W artykule przedstawiono wyniki badań uziarnienia i składu minerałów ciężkich w sześciu próbkach utworów środkowego miocenu (formacja z Machowa) z otworu wiertniczego Kazimierza Wielka (Donosy) PIG-1. Wyróżniona asocjacja granatów z cyrkonem, turmalinem, staurolitem i biotytem wskazuje na flisz karpacki jako najbardziej prawdopodobne źródło pochodzenia minerałów detrytycznych badanej formacji.
EN
The paper presents the results of grain size and mineral content studies of six samples taken from Middle Miocene deposits (Machów Formation) in the Kazimierza Wielka (Donosy) PIG-1 borehole. The distinguished garnet association with zirconium, tourmaline, staurolite, and biotite suggests the Carpathian Flysch Belt as the most possible source area of the detrital minerals in the formation.
EN
Detrital fragments of automorphic tourmaline crystals are commonly incorporated in tests of simple agglutinated foraminifera that lived in the deep-marine Carpathian turbidite basin, in which deposition of the Hieroglyphic beds (Eocene) took place. Such grains were observed in the tests of 37 taxa representing 20 species. However tourmaline occurs in the Carpathian Flysch sediments as an accessory mineral, still it was selected by the foraminifera as the only heavy mineral to be incorporated in their tests. The proportion of tourmaline-bearing specimens in an assemblage usually amounts to a few percent, but may reach 29% in extreme cases. The particular preference for tourmaline segregation and incorporation in the test walls is shown by the following genera: Psammosiphonella, Reophax, Bathysiphon and Nothia.
PL
W pracy scharakteryzowano czarny osad obecny w złożu wysoko wysortowanych piasków szklarskich z Osiecznicy. Czarny osad występujący na przedpolu eksploatacji w kopalni Osiecznica jest ekwiwalentem piasków szklarskich. W badanych koncentratach występują głównie tlenki tytanu (rutyl, anataz), cyrkon, śladowe ilości magnetytu z hematytem, tlenki i wodorotlenki manganu (psylomelan, piroluzyt) oraz materiał organiczny. Zawartość minerałów ciężkich w czarnym osadzie wynosi 2,87 % obj. Piaski szklarskie są silnie zanieczyszczone materią organiczną. Barwa czarna (brunatno-czarna) związana jest z obecności w szczelinach i pęknięciach w ziarnach kwarcu związków żelaza (hematytu), manganu (psylomelan, piroluzyt) oraz materiału organicznego.
EN
The composition of the black sediment from the glass sand in Osiecznica (Lower Silesia, SW Poland) was described. The Black sediment that occurs in the foreland of the mine operation is equivalent to Osiecznica glass sand. The studied concentrates consist mainly of titanium oxides (rutile, anatase), zirconium, small quantity of magnetite with hematite, manganese oxides and hydroxides (psylomelan, pyrolusite) and the organic material. The content of heavy minerals in the black sediment is 2.87% by volume. Glass sands are heavily contaminated with organic material. The black color (brownish-black) is related to the presence of perforation and cracks in the quartz of iron (hematite), manganese (psylomelan, pyrolusite) and organic material.
EN
An integrated heavy-mineral, mineral-chemical and zircon-dating study of the Triassic succession exposed on the south Devon coast, in the western part of the Wessex Basin, indicates derivation from a combination of granitic and metasedimentary lithologies of ages of mostly over 550 Ma. These sources were probably located at a relatively proximal location near the southern margin of the basin. Derivation from more distal sources in the Armorican Massif or local Variscan sources to the west appears unlikely in view of the scarcity of Permo-Carboniferous (Variscan-age) zircons. The Budleigh Salterton Pebble Bed Formation was derived from a different combination of source lithologies than the Otter Sandstone Formation, the former including staurolite-grade metasediments that were absent in the catchment area of the Otter Sandstone. The Devon coast succession has provenance characteristics that differ from equivalent sandstones further east in the Wessex Basin, and from sandstones in the East Irish Sea Basin to the north. These differences indicate that sediment supply patterns to the linked Triassic basin systems in southern Britain are complex, involving multiple distinct sub-catchment areas, and that heavy-mineral studies have considerable potential for unravelling these sub-catchment area sources.
EN
The heavy-mineral composition of the Weichselian fluvial successions deposited by an ephemeral meandering river and by a sand-bed braided river in the Toruń Basin (central Poland) was analysed. On the basis of a lithofacies analysis, in combination with the composition of the heavy-mineral assemblages, the fluvial processes and river-channel morphology were reconstructed. This allows determining the provenance of the fluvial deposits and the rivers’ discharge regimes. A model is proposed which can explain the changes in the amount of individual minerals in the fluvial sediments of different ages under the conditions of the oscillating Scandinavian ice sheet. The model assumes that, during the ice-sheet advances, the proglacial streams supplied large amounts of heavy minerals that were less resistant to mechanical abrasion. During the main phase of the ice-sheet retreat, the distance between the ice sheet and the Toruń Basin increased, and the amount of non-resistant minerals diminished as a result of sediment reworking in proglacial rivers. Due to the unique location of the Toruń Basin at the front of the Scandinavian ice sheet during the Weichselian glaciation, the heavy-mineral assemblages in the fluvial deposits form a valuable tool for the recognition of the ice-sheet extent.
EN
Part of northern Podlasie (NE Poland), shaped during the Wartanian stadial of the Odranian glaciation (Saalian), was situated in the periglacial zone during the Vistulian (Weichselian) glaciation. Both landforms and sediments were affected by the periglacial conditions. This is recorded at the Jałówka site, at the floor of a dry valley, where mineral deposits of 4.13 m thick, overlying organic deposits from the Eemian interglacial, were examined. These mineral deposits form four units, from bottom to top: a fluvial unit (I), a loess-like unit (II), a solifluction unit (III), and an aeolian unit with ice wedges (IV) on top of unit III. The heavy and light minerals were analysed, as well as the geochemistry, in order to find out about the parent material and to reconstruct the climatic conditions during deposition. The mineral analysis indicates that the Saalian till was predominantly derived from shallow-marine deposits; erosion accompanied by sorting of the heavy minerals took place on the basis of their mass and grain size. The original material of the till seems therefore to be sedimentary rocks from the eastern Central Baltic Basin. This material became strongly weathered under the periglacial conditions, resulting in the destruction of the quartz grains, as well as in leaching, leading to complete decalcification of the deposits. Aeolian activity resulted in infilling of ice wedges and the creation of thin layers. The intensity and the duration of these processes was limited, so that the effects of the aeolian abrasion are insignificant. Neither resulted the aeolian activity in significant reshaping of the landscape.
EN
Heavy mineral assemblages from the infill of Jurassic pre-Callovian palaeokarst in the Czatkowice Quarry, in the Kraków–Wieluń Upland, are zircon dominated. They contain also garnet, tourmaline, rutile and scarce grains of kyanite, staurolite and single chromian spinel. The textural features of the heavy minerals suggest that certain types of source rocks supplied the clastic material infilling in the karst studied. Most of the heavy minerals were derived from sedimentary or metasedimentary rocks as suggested by the high degree of roundness of the grains and also by high ZTR (zircon–tourmaline–rutile) index values. Rounded minerals may derive from Carboniferous, Permian and Triassic clastic rocks occurring in the area surrounding the Czatkowice Quarry. The chemical compositions of rounded detrital garnet and tourmaline grains suggest metamorphic and igneous rocks as initial sources, perhaps located in the Bohemian Massif. However, a hypothetical landmass located south of the Kraków–Wieluń Upland might have been an additional source area. The euhedral zircon and garnet grains were transported directly from crystalline rocks, which may have been Carboniferous-Permian volcanic rocks and crystalline basement elevations of Brunovistulicum exposed during Jurassic pre-Callovian sedimentation in the Czatkowice area.
EN
Conventional and high-resolution analyses of heavy minerals from the gravity flow-deposited sandstones of the Campanian–Maastrichtian interval of the Ropianka (Upper Cretaceous–Paleocene) and Menilite (Oligocene) formations of the Polish Carpathians display similar compositions in terms of mineral species. Zircon, tourmaline, rutile, garnet, staurolite and kyanite belong to the main constituents in both formations. Apatite is common in the Ropianka Fm., while the Menilite Fm. almost lacks this mineral. Furthermore, individual hornblende grains were found in the Ropianka Fm., while andalusite is present only in the Menilite Fm. The Ropianka Fm. is relatively richer in zircon, tourmaline, garnet and apatite, while the Menilite Fm. contains more staurolite and kyanite. Zircon and tourmaline colour and morphological varieties are similar in both formations. The similarities of the heavy mineral assemblages studied suggest origin of these minerals from lithologically similar rocks. Negative correlations between the zircon + tourmaline + rutile (ZTR) values and the content of garnet and staurolite in the Ropianka Fm. may indicate, to a large extent, first-cycle delivery of garnet and staurolite to the formation. Negative, but low, correlation valid only for ZTR and garnet and positive correlations for ZTR and staurolite and kyanite in the Menilite Fm. suggest delivery of these minerals from sedimentary rocks or/and palimpsest sediments. The data obtained on mineral relationships and their morphology suggest mixed first-cycle and recycled provenance of the heavy minerals studied. Additionally, the first-cycle material input seems to be larger during the Ropianka Fm. sedimentation, while during the deposition of Menilite Fm. the contribution of material delivered from erosion of recycled sediments appears more prominent. The heavy mineral evidence suggests a change at the northern margin of the Skole Basin from an immature passive margin with a high relief during sedimentation of the Campanian–Maastrichtian part of the Ropianka Fm. to a mature passive margin with a low relief during sedimentation of the Menilite Fm.
EN
Upper Cretaceous quartz arenites that fill the North Sudetic Synclinorium on the northern periphery of the Variscan Bohemian Massif show high compositional but low textural maturity. They have been interpreted for years as derived largely from nearby granite plutons, i.e. as first-cycle sediments. A different provenance was revealed on the basis of a combined light and heavy mineral analysis, and particularly a detrital tourmaline study, given that tourmaline is a sensitive indicator of granitic/metamorphic/sedimentary (multi-recycling) origin. Cenomanian, Turonian, Coniacian and Santonian sandstones contain abundant angular tourmaline grains, together with zircon and rutile, and subordinately staurolite, garnet, anatase, kyanite, sillimanite and monazite. The successive – Cenomanian to Santonian – tourmaline populations are similar with regard to shape, colour and chemical composition. The latter points unambiguously to various metamorphic rocks with a predominant group of Al-rich metapelites (Al-rich, F-poor dravite). It is concluded that, in the Late Cretaceous, large Sudetic granite plutons such as the Karkonosze and Strzegom–Sobótka massifs were not exposed but were buried under a thick siliciclastic cover. These results coupled with published apatite fission-track data from the granitic Karkonosze Pluton and the gneissic/migmatitic Góry Sowie Massif reveal that Late Cretaceous quartz arenites of the North Sudetic Synclinorium reflect gradual exhumation of the surrounding massifs, but do not record the final exposure of crystalline rocks. Since the latest Turonian, this exhumation corresponded to the Late Cretaceous inversion episode in Central Europe. The textural immaturity of Upper Cretaceous sandstones is misleading in terms of their recycled origin, and it is inherited from immature clastic source rocks.
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