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Addendum to the chemostratigraphy of the uppermost Callovian–middle Oxfordian interval of the Tethyan Fatricum domain (Tatra Mts, Krížna Nappe, southern Poland)

Jach Renata

Annales Societatis Geologorum Poloniae

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2021

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Vol. 91, No. 4

419--425

EN

New isotope (δ13C, δ18O of bulk carbonates) and carbonate content data from the uppermost Callovian–middle Oxfordian radiolarites of the Fatricum domain belonging to the north-western segment of the Tethys are added to previously published data. The new data supplement the Długa Valley section, the most nearly complete Bajocian–lower Tithonian section of the Krížna Nappe in the Tatra Mts. The uppermost Callovian and Lower Oxfordian bulk δ13C values (from 3.1 to 3.3‰) remain nearly constant with highly positive values. Therefore, the positive excursion identified in bulk carbonate δ13C values is interpreted as a record of the upper Callovian–middle Oxfordian global phenomenon. In this interval, a significant increase of CaCO3 content is recorded, which accompanies facies change from ribbon radiolarites with siliceous shale partings to calcareous radiolarites with rare shale intercalations. The abrupt CaCO3 increase may reflect a turning point in Early Oxfordian carbonate production and recovery of the marine carbonate factory.

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Neuro-fuzzy modelling of blending process in cement plant

Araromi D O, Odewale S A, Hamed J O

Advances in Science and Technology. Research Journal

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2015

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Vol. 9, nr 28

27--33

EN

The profitability of a cement plant depends largely on the efficient operation of the blending stage, therefore, there is a need to control the process at the blending stage in order to maintain the chemical composition of the raw mix near or at the desired value with minimum variance despite variation in the raw material composition. In this work, neuro-fuzzy model is developed for a dynamic behaviour of the system to predict the total carbonate content in the raw mix at different clay feed rates. The data used for parameter estimation and model validation was obtained from one of the cement plants in Nigeria. The data was pre-processed to remove outliers and filtered using smoothening technique in order to reveal its dynamic nature. Autoregressive exogenous (ARX) model was developed for comparison purpose. ARX model gave high root mean square error (RMSE) of 5.408 and 4.0199 for training and validation respectively. Poor fit resulting from ARX model is an indication of nonlinear nature of the process. However, both visual and statistical analyses on neuro-fuzzy (ANFIS) model gave a far better result. RMSE of training and validation are 0.28167 and 0.7436 respectively, and the sum of square error (SSE) and R-square are 39.6692 and 0.9969 respectively. All these are an indication of good performance of ANFIS model. This model can be used for control design of the process.

3

Węglanowość, obtoczenie ziaren i minerały ciężkie w formacjach paleogenu i neogenu środkowozachodniej Polski

Romanek A.

Biuletyn Państwowego Instytutu Geologicznego

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2010

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nr 438

123--135

PL

W 40 próbkach pochodzących z czterech formacji paleogeńskich (oligocen) i czterech formacji neogeńskich (miocen) zbadano standardowymi badaniami litopetrograficznymi węglanowość, obtoczenie materiału ziarnistego i skład minerałów ciężkich. Cechy te dobrze charakteryzują analizowane osady i mogą służyć do określania ich pozycji litostratygraficznej. Ma to szczególne znaczenie w badaniach stratygraficznych krótkich odcinków rdzeni wiertniczych, które są głównym materiałem badawczym analizowanych osadów na Niżu Polskim. Formacje morskie oligocenu charakteryzuje podwyższona węglanowość i średnie obtoczenie materiału ziarnistego. Formacje te różnicuje skład minerałów ciężkich. Formacje lądowe oligocenu i miocenu odznaczają się niską węglanowością, na ogół złym stopniem obtoczenia ziaren i znaczną wewnętrzną odmiennością składu i udziału minerałów ciężkich.

EN

The most indicative qualities of four Paleogene formations (Oligocene) and four Neogene formations (Miocene), 40 samples of which have been the subject of the standard lithopetrographic analysis, prove to be carbonate content, grain roundness and composition of heavy minerals. Consequently, on the basis of these features, the lithostratigraphic position of the sediments may be determined, which is of high importance for stratigraphic examinations of short drill core intervals remaining the main research material of the analyzed deposits of the Polish Lowland. Oligocene marine formations are characterized by high carbonate content, medium grain roundness and varying composition of heavy minerals. As far as Oligocene and Miocene continental formations are concerned, low carbonate content and generally angular grains as well as significant differences in the heavy minerals’ composition and percentage may be observed.