Wyniki wyszukiwania - BazTech

1

Geological and palaeogeographical peculiarities of the Adamów Graben area, central Poland

Widera Marek, Dzieduszyńska Danuta, Petera-Zganiacz Joanna

Geologos

|

2022

|

Vol. 28, No. 1

1--17

EN

From a geological and palaeogeographical point of view, the area of the Adamów Graben in the vicinity of Turek ranks amongst the best known in central Poland, with several opencast mines located here where lignite was exploited for 57 years. These large-surface exposures provide a good opportunity for detailed geological studies of strata of Late Cretaceous to Holocene age. However, the present research focuses mainly on those deposits, forms and structures that have been most thoroughly examined and are best exposed. These are Cretaceous marls and gaizes, Paleogene ‘blue clays’ and the ‘Koźmin Gravels’, Neogene sandstones, as well as the Quaternary glacial ‘Lake Koźmin’, involutions and ‘Koźmin Las’. Some of these, e.g., the ‘Koźmin Gravels’ and ‘Koźmin Las’, are not known from other Polish territories. Furthermore, results obtained by the authors over a period of nearly 30 years also include data on palaeogeographical changes across some Cenozoic intervals, especially during the early Oligocene and late Weichselian.

2

Forecasting surface water-level fluctuations of a small glacial lake in Poland using a wavelet-based artificial intelligence method

Piasecki A., Jurasz J., Adamowski J. F.

Acta Geophysica

|

2018

|

Vol. 66, no. 5

1093--1107

EN

Lake waters are a significant source of drinking water and contribute to the local economy (e.g. enabling irrigation, offering opportunities for tourism, waterways for transport, and meeting utility water demands); therefore, the ability to accurately forecast lake water levels is important. However, given the significant lack of research with respect to forecasting water levels in small lakes (i.e. 0.05 km2\area\10 km2), the present study sought to address this knowledge gap by testing a pair of hypotheses: (1) it is possible to forecast water levels in small surface lakes using artificial neural networks (ANN), and (2) better water-level forecasts will be obtained when the wavelet transform (WT) is used as an input data preprocessing tool. Based on an analysis of a case study in Lake Biskupinskie (1.16 km2) in Poland and based on a range of model performance statistics (e.g. mean absolute error, root mean square error, mean squared error, coefficient of determination, mean absolute percentage error), both hypotheses were confirmed for monthly forecasting of lake water levels. ANNs provided good forecasting results, and WT pre-processing of input data led to even better forecasts. Additionally, it was found that meteorological variables did not have a significant impact in forecasting water-level fluctuations. In light of the results and the limited scope of the present study, proposed future research directions and problems to be resolved are discussed.

3

Development and infill of Vistulian glacial Lake Gniew (N Poland) : a sedimentological analysis

Błaszkiewicz M., Gruszka B.

Geological Quarterly

|

2005

|

Vol. 49, No. 4

449--462

EN

A substantial glaciolacustrine unit in northern Poland, between the valleys of the Vistula and Wierzyca rivers, was deposited in glacial Lake Gniew during the climatic amelioration of the Late Vistulian. It covers an area of 35 km2 and has an average thickness of 7m, but locally reaches over 20 m. Four sedimentary facies are distinguished. The silty/clayey rhythmites of facies A are interpreted as varves from the central lake bottom. They represent the initial stage of lake development. Facies B is formed by a single sand layer that is interpreted as a turbidite originating during lake shallowing due to self-drainage. Facies C consists of massive clay with dropstones and dump structures. Two hypothesis regarding its genesis are put forward: the first assumes sedimentation in a shallow basin with a high input of homogenous fine-grained suspended sediment, whereas the second explains the facies as a result of amuddy jökulhlaup, pouring into Lake Gniew and being sourced from another glacial lake; further research is required to interpret this facies reliably. Facies D consists of thick silty/clayey rhythmites that are interpreted as prodeltaic deposits.

4

Glacioisostasy in northern Belarus: evidence and events

Pavlovskaya I.E.

Kwartalnik Geologiczny

|

1999

|

Vol. 43, Nr 2

169-176

EN

Evidence of glacioisostatic rebound within the ice marginal zone of the last glaciation is presented. The largest glacial lake of Belarus, i.e. the Polotsk lake situated at a short distance from the maximum limit of the Poozerie (Weichselian) Glaciation, was chosen as an object. Spectrum of glaciolacustrine terraces as well as succession of glaciolacustrine series are described. Differences of proximal and distal sequences are defined. Morphological and geological peculiarities of the Polotsk basin are conditioned by the glacioisostatic downwarping. The amplitude of glacioisostatic movements reached up to 40 m. Reconstruction of the events related to the glacioisostasy (shore displacement and water body migration) is given. Glacioisostatic rebound in areas with relatively small ice-loading had a discordant character.

PL

Przedstawiono niektóre wyniki badań geologicznych i geomorfologicznych z obszaru największego basenu zastoiskowego Białorusi, tj. zbiornika połockiego położonego na obszarze ostatniego zlodowacenia pomiędzy strefami marginalnymi fazy święciańskiej (frankfurckiej) i stadium brasławskiego (pomorskiego) zlodowacenia poozierskiego (wisły). Celem opracowania było prześledzenie linii brzegowych zbiornika i zmienności w osadach zastoiskowych, zmierzające do wyjaśnienia ewentualnego wpływu ruchów glaciizostatycznych na procesy sedymentacji glacilimnicznej i kształtowania rzeźby w strefie marginalnej lądolodu. Na podstawie analizy położenia dawnych linii brzegowych zbiornika płockiego stwierdzono zróżnicowane rozprzestrzenienie i genezę tarasów glacilimnicznych. W części proksymalnej obszaru zastoiska wyróżniono regresywne następstwo poziomów, w którym tarasy abrazyjne położone są niżej niż tarasy akumulacyjne. Na brzegu dystalnym występuje inwersja form brzegowych i starsze poziomy przykryte są młodszymi osadami tarasu akumulacyjnego. Zaznacza się również zróżnicowanie sekwencji proksymalnej i dystalnej osadów glacilimnicznych. Występują serie regresywne w proksymalnej części zastoiska i seria transgresywna w części dystalnej. Wymienione cechy budowy geologicznej i formy rzeźby zbiornika połockiego wskazują, że kształtowały się one pod wpływem obniżeń i wypiętrzeń związanych z glaciizostazją. Amplituda ruchów glaciizostatycznych sięgała 40 m, a reakcja na obciążenie przez lądolód ujawniała się podczas istnienia zbiornika, co spowodowało migrację wód jeziora w kierunku dystalnym, zmiany położenia linii brzegowych i depozycję transgresywnej sekwencji osadów.