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1

Lacustrine deltas and subaqueous fans: almost the same, but different – a review

Gruszka Beata, Zieliński Tomasz

Geologos

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2021

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Vol. 27, No. 1

43--55

EN

Although deltas and subaqueous fans are both formed in the same near-shore zones of basins, the hydraulic conditions for their formation, development and sedimentary records are different. The present review discusses the results of previously published studies of fan deltas (Gilbert-type deltas) and subaqueous fans of lacustrine and glaciolacustrine environments. The depositional mechanisms of deltas and subaqueous fans, textural and structural features of the lithofacies associations and their typical lithofacies are presented. The characteristics of subaqueous fans, which are still relatively poorly understood and are often overlooked in sedimentological interpretations of lacustrine sedimentary successions, receive particular attention. The palaeoenvironmental and lithological differences between deltas and subaqueous fans are highlighted.

2

Tectonic-climatic interactions during changes of depositional environments in the Carpathian foreland: An example from the Neogene of central Poland

Widera Marek, Zieliński Tomasz, Chomiak Lilianna, Maciaszek Piotr, Wachocki Robert, Bechtel Achim, Słodkowska Barbara, Worobiec Elżbieta, Worobiec Grzegorz

Acta Geologica Polonica

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2021

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Vol. 71, no. 4

519--542

EN

Many geological problems have not been convincingly explained so far and are debatable, for instance the origin and changes of the Neogene depositional environments in central Poland. Therefore, these changes have been reconstructed in terms of global to local tectonic and climatic fluctuations. The examined Neogene deposits are divided into a sub-lignite unit (Koźmin Formation), a lignite-bearing unit (Grey Clays Member), and a supra-lignite unit (Wielkopolska Member). The two lithostratigraphic members constitute the Poznań Formation. The results of facies analysis show that the Koźmin Formation was deposited by relatively high-gradient and well-drained braided rivers. Most likely, they encompassed widespread alluvial plains. In the case of the Grey Clays Member, the type of river in close proximity to which the mid-Miocene low-lying mires existed and then were transformed into the first Mid-Miocene Lignite Seam (MPLS-1), has not been resolved. The obtained results confirm the formation of the Wielkopolska Member by low-gradient, but mostly well-drained anastomosing or anastomosing-to-meandering rivers. The depositional evolution of the examined successions depended on tectonic and climatic changes that may be closely related to the mid-Miocene great tectonic remodelling of the Alpine-Carpathian orogen. This resulted in palaeogeographic changes in its foreland in the form of limiting the flow of wet air and water masses from the south and vertical tectonic movements.

3

Badania złóż soli kamiennej i potasowo-magnezowej prowadzone w Państwowym Instytucie Geologicznym

Czapowski Grzegorz, Peryt Tadeusz, Marek

Przegląd Geologiczny

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2019

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Vol. 67, nr 7

594--598

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.

4

The interpretative significance of ripple-derived sedimentary structures within an upper Neogene fluvial succession of central Poland

Maciaszek Piotr, Chomiak Lilianna, Wachocki Robert, Widera Marek

Geologos

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2019

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Vol. 25, No. 1

1--13

EN

Sedimentary structures discussed in the present study are genetically linked to ripples that consist of pure sand or alternating sand and mud layers. All types of ripple-related structures, such as climbing-ripple cross-lamination and heterolithic bedding, i.e., flaser, wavy and lenticular (nodular), have been identified for the first time in fluvial strata that have been characterised previously as commonly massive. These small-scale bedforms, produced by migrating ripples, have been documented in a fluvial channel of late Neogene age in central Poland. The abundance and co-occurrence of the structures discussed and their spatial distribution provide evidence of their formation under very low-energy conditions, when flow velocity changed markedly, but was often significantly less than 0.5 m/s. Therefore, these ripple-derived sedimentary structures are here recognised as typical of channel fills of an anastomosing river.

5

Secular and catastrophic processes reflected in sediments of the Suchedniów water reservoir, Holy Cross Mountains (Poland)

Przepióra Paweł, Kalicki Tomasz, Aksamit Michał, Biesaga Piotr, Frączek Marcin, Grzeszczyk Paulina, Malęga Emanuela, Chrabąszcz Mariusz, Kłusakiewicz Edyta, Kusztal Piotr

Geologos

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2019

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Vol. 25, No. 2

139--152

EN

The Suchedniów water reservoir is located in the central section of the River Kamionka in the northern part of the Holy Cross Mountains of central Poland. This area once belonged to the Old Polish Industrial District that, during the Middle Ages, was very intensively developed by iron metallurgy. Many forges and mills along the rivers used water power, which led to the construction of an anthropogenic, small-scale water retention system. At the beginning of the twentieth century many of these reservoirs were drained after the collapse of metallurgical activities. The present-day reservoir was built in 1974 and drained in 2017. Research into the drained basin has documented various forms and sediments, some of which record present-day depositional processes (fire proof clay layer, inland fan delta), while others represent the historical period (lacustrine sediments of older reservoirs). Traces of catastrophic events have been preserved as well; an assemblage of megaripples marks the sudden drainage caused by a dam break in 1974.

6

Evolution of Early Pleistocene fluvial systems in central Poland prior to the first ice sheet advance – a case study from the Bełchatów lignite mine

Goździk J., Zieliński T.

Geologos

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2017

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Vol. 23, No. 2

89--107

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.

7

Silurian stratigraphy of Central Iran - an update

Hairapetian V., Ghobadi Pour M., Popov L. E., Männik P., Miller C. G.

Acta Geologica Polonica

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2017

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Vol. 67, no. 2

201--233

EN

The Silurian biostratigraphy, lithostratigraphy, and facies of Central Iran including the Kashmar (Boghu Mountains), Tabas (Derenjal Mountains, Ozbak-Kuh), Anarak (Pol-e Khavand) and Kerman regions is reviewed and updated. The current state of knowledge of the Silurian in the Zagros Basin, Alborz, Kopet-Dagh and Talysh regions, as well as in a few areas scattered across the Sabzevar Zone, and the Sanandaj-Sirjan terranes is also reviewed. Silurian volcanism in various parts of Iran is briefly discussed. The end of the Ordovician coincided with a widespread regression across Iran synchronous with the Hirnantian glaciation, and only in the Zagros Basin is there a continuous Ordovician–Silurian transition represented by graptolitic black shales of the Sarchahan Formation. In the Central-East Iranian Platform marine sedimentation re-commenced in the early to mid Aeronian. By the Sheinwoodian, carbonate platform depositional environments were established along its north-eastern margin. In other parts of Iran (e.g., Kopet-Dagh and the Sabzevar Zone), siliciclastic sedimentation continued probably into the late Silurian. The Silurian conodont and brachiopod biostratigraphy of Central Iran is significantly updated facilitating a precise correlation with the Standard Global Chronostratigraphic Scale, as well as with key Silurian sections in other parts of Iran. The Silurian lithostratigraphy is considerably revised and two new lithostratigraphical units, namely the Boghu and Dahaneh-Kalut formations, are introduced.

8

Factors controlling sedimentation in the Toruń-Eberswalde ice-marginal valley during the Pomeranian phase of the Weichselian glaciation: an overview

Pisarska-Jamroży M.

Geologos

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2015

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Vol. 21, No. 1

1--29

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.

9

Quantity and quality of organic carbon in bottom sediments of two upland dam reservoirs in Poland

Smal H., Ligęza S., Baran S., Wójcikowska-Kapusta A.

Environment Protection Engineering

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2015

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Vol. 41, nr 1

95--110

EN

The quantity and quality of organic carbon were studied in bottom sediments of two small, shallow, polymictic dam reservoirs located in SE Poland: Zalew Zemborzycki (ZZ) and Brody Iłżeckie (BI). Total content of organic carbon (Corg), and its fractions have been determined. The maps of Corg spatial distribution have been compiled. Wide ranges of sedimentary Corg were noted as well as differences between two reservoirs in respect of its content and spatial distribution. The Corg content in the sediments showed a longitudinal zonation pattern in the ZZ and a transverse one in the BI. The composition of sedimentary Corg showed the highest percentage of the insoluble fraction followed by humus acid fraction and the lowest – hemicelluloses fraction. In the humus acid fraction, fulvic acids overbalanced humic acids.

10

Small-scale cyclic deposition in the Frasnian (Upper Devonian) of the Holy Cross Mountains, Poland

Vierek A.

Geologos

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2014

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Vol. 20, No. 4

239--258

EN

In sections exposing Frasnian limestones at five outcrops in the Holy Cross Mountains, five lithofacies (L1 to L5) that represent upper slope to basinal environments are identified. These lithofacies are characterised by dark-coloured micritic limestones–marly shale couplets with many light-coloured intercalations of fine- to coarse-grained limestones (= event beds). This lithofacies pattern characterises mostly low-energy domains punctuated by storm episodes. In addition, these upper-slope to basinal lithofacies are arranged into small-scale, coarsening-upward beds and cycles. The cycles are locally composed of fining/thinning-upward beds. The small-scale cycles have a calculated duration of 19 to 42 kyr. The differential thickness of beds and cycles within and between sections was probably caused by differential subsidence and local tectonics. Possible evidence of tectonic activity is also related to a difference in number of cycles recorded in the time-equivalent sections. The recognised cyclicity shows sea-level fluctuations and a few deepening episodes. Some of them are correlated with the Timan global eustatic events. However, local tectonics and episodic subsidence may have played a significant role in recording brief deepening pulses. Thus, low-amplitude sea-level changes were major factors in platform generation and evolution in the Frasnian of the Holy Cross Mountains modified by local, block-related subsidence.

11

Kame or moraine? A sedimentological study of a glaciomarginal landform at Niedźwiedziny (Great Polish Lowland)

Ewert-Krzemieniewska A.

Geologos

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2014

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Vol. 20, No. 3

167--181

EN

A sedimentary succession in a gravel pit at Niedźwiedziny was investigated in order to determine its origin: kame or moraine. The gravel pit is located in an isolated hill of approx. 600 m long and 250–400 m wide. The succession is built of glaciofluvial deposits: a sandy/gravelly unit in the lower and middle parts, overlain by diamicton. Five lithofacies have been distinguished, which represent two facies associations: (1) a fluvial association evolving from a high-energy to a transitional to a shallow braided river on an alluvial fan, and (2) an association of cohesive deposits representing a glacigenic mass flow. The interpretation is based mainly on palaeocurrent data and differs from conclusions by earlier investigators. The ice-marginal zone is characterised by a large variety of glaciomarginal forms. Their sedimentology, morphology and palaeogeography are determined by successive phases of deglaciation. The results of the present study show that the character of the deglaciation in the study area changed with time from frontal to areal deglaciation.

12

Profil sedymentologiczny przedkelowejskich (jurajskich) utworów silikoklastycznych w otworze badawczym Cianowice 2 (okolice Krakowa)

Pieńkowski G.

Biuletyn Państwowego Instytutu Geologicznego

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2014

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nr 459

147--156

PL

W otworze Cianowice 2 (okolice Krakowa), bezpośrednio na niezgodności erozyjnej ze zmetamorfizowanymi łupkami neoproterozoiku (ediakaru), a pod węglanowymi utworami jury środkowej (keloweju), występuje ponad 20-metrowy kompleks utworów silikoklastycznych (brekcje, zlepieńce, piaskowce, mułowce z podrzędnymi wkładkami węgli, syderytów i margli). Wykonane w czterech próbkach analizy palinologiczne pozwoliły uzyskać stosunkowo ubogi zespół miosporowy o szerokim zasięgu stratygraficznym, niedający rozstrzygających rezultatów, potwierdzający bardzo ogólnie jedynie jurajski wiek utworów (Jadwiga Ziaja, inf. ustna). Pozycja stratygraficzna tych utworów nie jest jasna – mogą one należeć zarówno do wczesnej jury, do środkowej jury, jak i obu tych epok, a najniższe warstwy grubookruchowe mogą być jeszcze starsze i reprezentować późny trias. Cały nawiercony kompleks silikoklastyczny został podzielony na pięć wyraźnych sukcesji. W poszczególnych sukcesjach dominują podrzędne cykle proste o ziarnie (i energii przepływu) malejący ku górze. Sukcesja 1 składa się z brekcji i zlepieńców o nieuporządkowanej strukturze, co wskazuje na spływy mułowe (soliflukcyjne), przechodzące być może w spływy wodne w środowisku stożków aluwialnych. Sukcesja 2 składa się z pięciu cykli prostych piaszczysto-mułowcowych, ze śladami wegetacji roślinnej, utworzonych na równi rzecznej. Sukcesja 3 składa się w całości z mułowców o genezie jeziorno-bagiennej, z licznymi śladami wegetacji roślinnej i węglami w stropie. Sukcesje 4 i 5 to ponownie sukcesje złożone z cykli prostych o genezie rzecznej. Cały profil badanych utworów silikoklastycznych wykazuje peneplenizację żywej początkowo rzeźby obszarów źródłowych i ciągły spadek energii procesów depozycyjnych ku górze aż do stropu sukcesji 3 z węglami, a następnie ponowny nawrót równi rzecznej. Poszczególne sukcesje są oddzielone powierzchniami nieciągłości (przeważnie erozyjnymi, jedynie spąg sukcesji 3 ma charakter odpowiednika powierzchni mogącej być korelatywną powierzchnią transgresji), które mogą stanowić regionalne powierzchnie korelacyjne (zwłaszcza dolne granice sukcesji 1, 3 i 5). Sukcesje o dolnych granicach erozyjnych mogą odpowiadać sekwencjom depozycyjnym. Porównania regionalne otworu wiertniczego Cianowice 2 z otworem Parkoszowice 58 BN położonym ok. 40 km na północny zachód skłaniają do uznania tych utworów wstępnie za jurę dolną (najprawdopodobniej pliensbach–toark), grubookruchowe utwory sukcesji 1 w spągu otworu mogą reprezentować także wiek późnotriasowy. Do czasu uzyskania bardziej precyzyjnych danych biostratygraficznych lub chemostratygraficznych nie można potwierdzić tego z całą pewnością ponad stwierdzenie, że są to utwory jurajskie starsze od keloweju.

EN

In the Cianowice 2 borehole (located in the vicinity of Kraków), straight on the erosional unconformity on the top of metamorphosed Neo-Proterozoic (Ediacaran) shales and below carbonate deposits of Callovian, 20 meters thick interval of siliciclastic rocks has been encountered. The siliciclastic rocks are composed of conglomerates, sandstones, mudstones and subordinate intercalations of coal, siderite and marls. Stratigraphical position of this interval can be inferred based on poorly-preserved miospore assemblage, spanning relatively long geological time (Jadwiga Ziaja, pers. comm.) – it can represent either Early or Middle Jurassic, or both of those epochs, while the lowermost coarse-grained package can be even of an older, i.e. Triassic age. The interval was subdivided into 5 well-distinguished sedimentary successions, separated by bounding surfaces, mostly of erosional character – only succession 3 starts with sharp lithological contrast between sandy deposits and overlying mudstones, which reflects flooding and rapid retrogradation (either lacustrine or lagoonal). All these bounding surfaces (particularly bottoms of successions 1, 3 and 5) are of regional correlative significance-erosional bounding surfaces can represent sequence boundaries, while bottom of the succession 3 can represent correlative surface of a transgression. In each succession, except for the lowermost one, subordinate fining-upward cycles are dominating. They represent diminishing-upward energy of transport. The succession 1 is composed of breccia and conglomerates with chaotic structure, indicative of mudflow – dominated fans, possibly passing into alluvial fans and back to the mudflow fan again in the top. There is a marked lithological contrast (possibly connected also with considerable hiatus) between the coarse-grained deposits of succession 1 and following successions built of fine-grained sandstones, siltstones, mudstones and claystones. The succession 2 is composed of five fining-upward cycles, indicative of fluvial environment (fluvial plain), with traces of plant vegetation. The succession 3 is entirely composed of mudstones of lacustrine origin, with numerous traces of plant vegetation, siderite concretions and bands and coals at the top. Successions 4 i 5 again contain typical fining-upward fluvial cycles with traces of plant vegetation. The overall profile shows peneplanation of a landscape and continuous diminishing of energy of sedimentary processes up to the top of succession 3 marked with coals. Then, fluvial sedimentation returned. Regional comparison of the Cianowice 2 borehole with borehole Parkoszowice 58 BN, located some 40 km to NW tends to suggest the Early Jurassic (most probably Pliensbachian–Toarcian) age of the profile (the lowermost coarse-grained part can be of a Triassic age), but until more reliable biostratigraphical or chemostratigraphical evidences are obtained, these more detailed interpretations of stratigraphical division remain tentative.

13

Sedimentology of the Early Jurassic terrestrial Steierdorf Formation in Anina, Colonia Cehă Quarry, South Carpathians, Romania

Kędzior A., Popa M. E.

Acta Geologica Polonica

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2013

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Vol. 63, no. 2

175--199

EN

Authorship issues are clarified, new photographic documentation is provided and emended systematic descriptions are presented for the oldest Cambrian trilobite taxa from the Holy Cross Mountains (Poland). Biostratigraphic analysis of the fauna allows correlation with the traditional Holmia kjerulfi-group Zone of Scandinavia, the Callavia Zone of Britain and Newfoundland, the lower and middle part of the Sectigena Zone of Morocco and the Marianian Stage of Spain. The trilobites display a strong biogeographic signal linked with West Gondwana and Avalonia and a suggestion is made that the TESZ margin of Baltica with the Malopolska Massif was liable to currents from those areas that distributed planktonic trilobite larvae.

14

Macroscopic lithotype characterisation of the 1st Middle-Polish (1st Lusatian) Lignite Seam in the Miocene of central Poland

Widera Marek

Geologos

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2012

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Vol. 18, No. 1

1--11

EN

The 1st Middle-Polish (1st Lusatian) Lignite Seam is exploited in open-cast mines in central Poland. A large number of lignite lithotypes, grouped in four lithotype associations, are distinguished: xylitic, detritic, xylo-detritic and detro-xylitic lithotype associations, which show various structures. Each lithotype association was produced under specific peat-forming environmental conditions. In the case of the lignite seams under study they represent all the main environments that are known from Neogene mires, i.e.: fen or open water, bush moor, wet forest swamp and dry forest swamp. For a simple and practical description in the field of both the lignite sections and borehole cores, a new codification for lignite lithotypes is proposed. It is based on the codification of clastic deposits (lithofacies). The practical value of the new lignite lithotype codification is examined in three vertical sections of the 1st Middle-Polish Lignite Seam.

15

Miocene burrows of the Ghost Crab Ocypode and their environmental significance (Mykolaiv Sands, Fore-Carpathian Basin, Ukraine)

Radwański A., Wysocka A., Górka M.

Acta Geologica Polonica

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2012

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Vol. 62, no. 2

217-229

EN

The huge lithosome of the Middle Miocene (Early Badenian) Mykolaiv Sands, developed at the external margin of the Fore-Carpathian Basin in western Ukraine, is recognized to represent a shallowing-up sequence. Special attention is paid to burrows of the Ghost Crab Ocypode which are pantropical in present-day littoral habitats. In the Stratyn section, burrows of this type become a crucial tool in the interpretation of basin bathymetry, which starts from distal offshore depths, through the foreshore, to the backshore where the Ocypode burrows record a temporary break in sedimentation. Lithification of the sand layers and the Ocypode burrows subsequently progressed in beachrock mode. The Stratyn section demonstrates that the development of submerged shoals and/or emergent parts, throughout the huge mass of the Mykolaiv Sands, is probably responsible for their great variation in thickness in western Ukraine, which has long proved difficult to explain.

16

Stratigraphy and sedimentology of the Niger Delta

Reijers T. J. A.

Geologos

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2011

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Vol. 17, No. 3

133--162

EN

During the Cenozoic, until the Middle Miocene, the Niger Delta grew through pulses of sedimentation over an oceanward-dipping continental basement into the Gulf of Guinea; thereafter progradation took place over a landward-dipping oceanic basement. A 12,000 m thick succession of overall regressive, of flapping sediments resulted that is composed of three diachronous siliciclastic units: the deep-marine pro-delta Akata Group, the shallow-marine delta-front Agbada Group and the continental, delta-top Benin Group. Regionally, sediment dispersal was controlled by marine transgressive/regressive cycles related to eustatic sea-level changes with varying duration. Differential subsidence locally influenced sediment accumulation. Collectively, these controls resulted in eleven chronostratigraphically confined delta-wide megasequences with considerable internal lithological variation. The various sea-level cycles were in or out of phase with each other and with local subsidence, and interfered with each other and thus influenced the depositional processes. At the high inflection points of the long-term eustatic sea-level curve, floodings took place that resulted in delta-wide shale markers. At the low inflection points, erosional channels were formed that are often associated, downdip, with turbidites in low-stand sediments (LSTs). The megasequences contain regional transgressive claystone units (TST) followed by a range of heterogeneous fine-to-coarse progradational or aggradational siliciclastic (para)sequence sets formed during sea-level high-stand (HST). An updated biostratigraphic scheme for the Niger Delta is presented. It also updates a sedimentation model that takes into consideration local and delta-wide effects of sea-level cyclicity and delta tectonics. Megasequences were formed over time intervals of ~5 Ma within individual accurate megastructures that laterally linked into depobelts. The megasequences form the time-stratigraphic frame of the delta and are the backbone for the new delta-wide lithostratigraphy proposed here. Such a new lithostratigraphy is badly needed, in particular because of the vigorous new activity in the offshore part of the Niger Delta (not covered in this contribution). There, as well as in the onshore part of the delta, the traditional lithostratigraphic subdivision of the Cenozoic Niger Delta section into three formations is insufficient for optimum stratigraphic application; moreover, the various informal subdivisions that have been proposed over time are inconsistent.

17

Content of selected heavy metals in water and riverbed sediments of the Utrata River

Wojtkowska M.

Environment Protection Engineering

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2011

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Vol. 37, nr 3

55-62

EN

The results of study of heavy metals content in water, suspended solids and bottom sediments of the Útrata River have been presented. The highest concentrations were observed for the dissolved form of Pb (0.35 mg/dm 3). All heavy metals under investigation were present in suspended solids (over 90%). Remarkable amount have also been found in sediments [mg/kg] Zn - 174, Cu - 76, Pb - 49, and Cd - 2.5. Water extracts showed lower concentrations, while EDTA extraction was several times more efficient (over 26%).

18

The evolution of late Ediacaran riverine-estuarine system in the Lublin-Podlasie slope of the East European Craton, southeastern Poland

Pacześna J.

Polish Geological Institute Special Papers

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2010

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Vol. 27

1-96

EN

A model of evolution and destruction of the late Ediacaran riverine-estuarine system that developed in the Podlasie Depression and Lublin-Podlasie slope of the East European Craton is presented based on the identification and definition of facies associations, depositional systems and the framework of high-resolution sequence stratigraphy. Two groups of depositional systems have been identified - alluvial, estuarine, and one open coast system. The alluvial system was initially represented in the northeastern and western synrift depocentres by alluvial fans. Distal parts of the fans were areas of fluvial deposition. Large, sand-bed braided rivers flowed transverse to the sedimentary basin axis. During final stages of the alluvial basin evolution, the levelling of the rift topography and the increase in subsidence rate in the south-east of the basin resulted in the development of anastomosed system rivers. The rivers flowed along the basin axis from north to south. A change in the braided-river flow type from ephemeral during the early stage of the alluvial basin evolution to perennial in the later stages, development of anastomosed system river floodplains and the change in the colour of accumulated fluvial deposits indicate a climate change from arid and desert to more humid and moderate conditions. The late Ediacaran siliciclastic succession of the Lublin basin is a record of the transgressive stage of estuary development. It is manifested by five successive parasequences composing the transgressive systems tract. During the earliest evolutionary stages, the Lublin estuary was a mixed wave-and tide-dominated. In its peak development, as the influence of tides significantly increased, it turned into a macrotidal, hypersynchronous estuary of funnel-shaped geometry. Regression of the Lublin estuary, resulting in its ultimate decline, started along with the highstand development at the Ediacaran/Cambrian transition. The estuary became transformed into a mixed-energy wave-and tide-dominated estuarine system and subsequently into a wave-dominated open coast.

PL

Na podstawie zdefiniowania asocjacji facjalnych i systemów depozycyjnych oraz przedstawienia ram wydzieleń wysokorozdzielczej stratygrafii sekwencji sformułowano model rozwoju i destrukcji późnoediakarskiego systemu fluwialno-estuariowego, rozprzestrzenionego w obniżeniu podlaskim i lubelskim skłonie kratonu wschodnioeuropejskiego. Wyróżniono dwie grupy systemów depozycyjnych - aluwialne i estuariowe oraz system otwartego wybrzeża. System aluwialny był początkowo reprezentowany w północno-wschodnich i zachodnich depocentrach synryftowych przez stożki aluwialne. Dystalne części stożków były obszarami depozycji fluwialnej. Duże, piaskodenne rzeki roztokowe spływały poprzecznie do osi basenu sedymentacyjnego. W końcowych stadiach ewolucji basenu aluwialnego wyrównanie topografii ryftowej i wzrost tempa subsydencji w jego południowo-wschodniej części spowodowały rozwój rzek systemu anastomozującego. Spływały one wzdłuż osi basenu z północy na południe. Zmiana rodzaju przepływu rzek roztokowych z okresowego we wczesnych etapach rozwoju basenu aluwialnego na ciągły w późniejszych stadiach, rozwój równi zalewowych rzek systemu anastomozującego i zmiana koloru osadów akumulowanych przez rzeki świadczą o zmianie klimatu suchego, pustynnego na bardziej wilgotny, umiarkowany. Późnoediakarska sukcesja silikoklastyczna basenu lubelskiego jest zapisem transgresywnego etapu ewolucji estuarium. Jej przebieg odzwierciedla pięć kolejnych parasekwencji budujących transgresywny ciąg systemowy. W najwcześniejszych etapach rozwoju estuarium lubelskie miało charakter mieszany, falowo-pływowy. W fazie maksymalnego rozwoju, w miarę znaczącego wzrostu oddziaływania pływów, było to makropływowe, hypersynchroniczne estuarium o kominowej geometrii. Na przełomie ediakaru i kambru wraz z rozwojem ciągu systemowego wysokiego stanu względnego poziomu morza rozpoczął się regres i stopniowa likwidacja estuarium lubelskiego, które przekształciło się w estuarium o mieszanej energii falowo-pływowej i następnie w otwarte wybrzeże z udziałem falowania.

19

Unusual development of sandur sedimentary succession, an example from the Pleistocene of S Poland

Salamon Tomasz, Zieliński Tomasz

Geologos

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2010

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Vol. 16, No. 2

83--99

EN

An atypical lithological development of outwash deposits in the Carpathians Foreland (S Poland) shows lower and middle parts of the sedimentary succession that are characterized by sinuous palaeochannels. This channel facies consists of laterally accreted sands derived from side bars. The sedimentary environment was a proglacial system of anabranching channels, presumably of anastomosed type. The outwash channel pattern was most probably controlled by the raising base level of the fluvial system. Both proglacial and extraglacial waters were dammed by a sandur within a small upland valley. Aggradation and progradation of the glaciofluvial deposits resulted in progressive rising of the dammed lake level. The low hydraulic gradient of the outwash streams resulted in a sinuous planform as well as a lowenergy style of deposition. Afterwards, the rising lake water was drained off through a low watershed and the entire valley became filled with outwash sediments. The bedrock morphology thus became buried and a typical unconfined sandur with a braided channel network developed during the last phase of the glaciomarginal sedimentation (upper part of the sedimentary succession under study).

20

Struktury glacitektoniczne a dynamika lądolodu zlodowacenia Wisły na zachodnim skłonie Garbu Lubawskiego

Gałązka D., Rychel J., Krysiak Z.

Prace Państwowego Instytutu Geologicznego

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2009

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T. 194

27--34

PL

Garb Lubawski z kulminacją Wzgórz Dylewskich to obszar masowego występowania struktur glacitektonicznych, związanych z istnieniem w tym rejonie szeregu różnoskalowych stref międzylobowych ukształtowanych podczas stadiału głównego zlodowacenia Wisły. Różna dynamika, charakter i czas transgresji lądolodu lobów wiślanego i mazurskiego w czasie ostatniego zlodowacenia znajdują odzwierciedlenie w następstwie struktur glacitektonicznych obserwowanych w odsłonięciach. Odkrywka w rejonie Rożentala umożliwia prześledzenie przebiegu procesów sedymentacyjnych i glacitektonicznych, które doprowadziły do powstania kilkudziesięciu bliźniaczo podobnych form szczelinowych znajdujących się na zachodnim skłonie Garbu Lubawskiego. Jądro omawianej formy w Rożentalu powstało podczas deglacjacji frontalnej pierwszego, maksymalnego nasunięcia lądolodu stadiału głównego zlodowacenia Wisły, najprawdopodobniej jako stożek marginalny. Podczas kolejnej (lub kolejnych) oscylacji czoła lądolodu wzgórze to zostało przebudowane we wrzecionowatą formę szczelinową.

EN

The Lubawa Ridge with Dylewskie Heights are abundantin glaciotectonic phenomena related to many intra-lobe zones (varied in scale) observed in this area. These zones were formed during the main stage of the Weichselian (= Vistulian) Glaciation. Different dynamics and timing of the advance of the Vistulian and Mazury lobs from the Last Glaciation are reflected in the succession of glaciotectonic structures observed in the Rożental outcrop.The Rożental outcrop is unique for investigation of sedimentary and glaciotectonic processes. Rożental hill is one of several tens of crevasse landforms present on the western slope of the Lubawa Ridge. Rożental hill was created during frontal deglaciation of the first-maximal Weichselian ice-sheet advance (the main stage). Primarily, it was probably an ice-marginal fan. The hill was rebuilt into a spindle-shaped crevasse landform during the next oscillation (or oscillations) of the glacier front.