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Tytuł:
Air Quality Assessment and Forecasting Using Neural Network Model
Autorzy:
Hamdan, Mohammad A.
Ata, Mohammad F. Bani
Sakhrieh, Ahmad H.
Powiązania:
https://bibliotekanauki.pl/articles/1838288.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
air pollutant
ANN
MATLAB
forecasting
Opis:
Air pollution is a major obstacle faced by all countries which impacts the environment, public health, socioeconomics, and agriculture. In this study, the air pollutants in the city of Amman were presented and analyzed. Nonlinear Autoregressive Exogenous (NARX) model was used to forecast the daily average levels of pollutants in Amman, Jordan. The model was built using the MATLAB software. The model utilized a Marquardt-Levenberg learning algorithm. Its performance was presented using different indices, R2 (Coefficient of Determination), R (Coefficient of Correlation), NMSE (Normalized Mean Square Error), and Plots representing network predictions vs original data. Historical measurements of air pollutants were obtained from 4 of the Ministry of Environment (MoEnv) air quality monitoring stations in Amman. The meteorological data representing three years (2015, 2016, and 2017) were used as predictors to train the Artificial Neural Network (ANN) while the data of the year 2018 were used to test it. The results showed good performance when forecasting SO2, O3, CO, and NO2, and acceptable performance when forecasting Particulate Matter (PM10) at the given 4 locations.
Źródło:
Journal of Ecological Engineering; 2021, 22, 6; 1-11
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Air Quality Assessment and Forecasting Using Neural Network Model
Autorzy:
Hamdan, Mohammad A.
Ata, Mohammad F. Bani
Sakhrieh, Ahmad H.
Powiązania:
https://bibliotekanauki.pl/articles/1838392.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
air pollutant
ANN
MATLAB
forecasting
Opis:
Air pollution is a major obstacle faced by all countries which impacts the environment, public health, socioeconomics, and agriculture. In this study, the air pollutants in the city of Amman were presented and analyzed. Nonlinear Autoregressive Exogenous (NARX) model was used to forecast the daily average levels of pollutants in Amman, Jordan. The model was built using the MATLAB software. The model utilized a Marquardt-Levenberg learning algorithm. Its performance was presented using different indices, R2 (Coefficient of Determination), R (Coefficient of Correlation), NMSE (Normalized Mean Square Error), and Plots representing network predictions vs original data. Historical measurements of air pollutants were obtained from 4 of the Ministry of Environment (MoEnv) air quality monitoring stations in Amman. The meteorological data representing three years (2015, 2016, and 2017) were used as predictors to train the Artificial Neural Network (ANN) while the data of the year 2018 were used to test it. The results showed good performance when forecasting SO2, O3, CO, and NO2, and acceptable performance when forecasting Particulate Matter (PM10) at the given 4 locations.
Źródło:
Journal of Ecological Engineering; 2021, 22, 6; 1-11
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antibacterial activity of iron oxide nanoparticles synthesized by co-precipitation technology against Bacillus cereus and Klebsiella pneumoniae
Autorzy:
Ansari, S. A.
Oves, M.
Satar, R.
Khan, A.
Ahmad, S. I.
Jafri, M. A.
Zaidi, S. K.
Algahtani, M. H.
Powiązania:
https://bibliotekanauki.pl/articles/778380.pdf
Data publikacji:
2017
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
antibacterial activity
co-precipitation
iron oxide nanoparticles
Klebsiella pneumoniae
physico-chemical characterization
Opis:
The present study investigates the synthesis and characterization of iron oxide nanoparticles (Fe3 O4 -NPs) for their antibacterial potential against Bacillus cereus and Klebsiella pneumonia by modified disc diffusion and broth agar dilution methods. DLS and XRD results revealed the average size of synthesized Fe3 O4 -NPs as 24 nm while XPS measurement exhibited the spin-orbit peak of Fe 2p3/2 binding energy at 511 eV. Fe3 O4 -NPs inhibited the growth of K. pneumoniae and B. cereus in both liquid and soild agar media, and displayed 26 mm and 22 mm zone of inhibitions, respectively. MIC of Fe3 O4 -NPs was found to be 5 μg/mL against these strains. However, MBC for these strains was observed at 40 μg/mL concentration of Fe3 O4 -NPs for exhibiting 40–50% loss in viable bacterial cells and 80 μg/mL concentration of Fe3 O4 -NPs acted as bactericidal for causing 90–99% loss in viability. Hence, these nanoparticles can be explored for their additional antimicrobial and biomedical applications.
Źródło:
Polish Journal of Chemical Technology; 2017, 19, 4; 110-115
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Assessment of Wildlife Conservation Awareness and practices in some selected secondary school around Kainji Lake National Park, Nigeria
Autorzy:
Akande, O. A.
Ahmad, Y. A.
Yusuf, H. O.
Akinade, T. G.
Powiązania:
https://bibliotekanauki.pl/articles/1076522.pdf
Data publikacji:
2019
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Awareness
Practices and Secondary school
Wildlife conservation
Opis:
One of the challenges facing wildlife conservation is how to change the way people perceive wildlife. Therefore this study examine wildlife conservation awareness and practices in some selected secondary school around Kainji Lake National Park. Data was collected through the use of pre tested structured questionnaires among six selected secondary school in the study area. The sample of the research was one hundred (100) respondents. Data was analysis using descriptive statistics. The findings reveals that majority of the respondents (74%) are male and age group 15-20 years had the highest with 43%. 63% of the respondents are aware of wildlife conservation in the study area and majority (66%) of the respondent has not visit the Kainji Lake National Park. 50% of the respondents had about wildlife through direct communication. 63% and 80% of the respondents are willing and are ready to support wildlife conservation in the study area. The finding still reveal that awareness is still lacking in most schools among the communities. Therefore more wildlife conservation awareness is needed in our various schools so as to get the interest of the students when they are still young so that generation coming will also be thought.
Źródło:
World Scientific News; 2019, 115; 91-103
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bioaccumulation of Heavy Metals in Mackerel and Red Hybrid Tilapia Collected From
Autorzy:
Dabwan, Ahmed H. A.
Saluddin, Ummu Asma’ Hafifah Bt. Mohmad
Isa, Nursuhaili Bt. Mohd
Abdullah, Abdul Hadi
Mohamed, Amri Bin Hj.
Ahmad, Anuar Bin
Powiązania:
https://bibliotekanauki.pl/articles/27314829.pdf
Data publikacji:
2022
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
heavy metals
biomonitoring
oreochromis niloticus
Rastrelliger kanagurta
Oreochromis niloticus
metale ciężkie
ekosystem morski
makrela indyjska
tilapia
Opis:
The major goal of this study is to determine the bioaccumulation of heavy metals in the tissues and bones of Red Hybrid Tilapia (Oreochromis niloticus) and Mackerel (Rastrelliger kanagurta) taken from two distinct sites in Terengganu state, Malaysia, namely Kijal and Paka. Zinc (Zn), copper (Cu), nickel (Ni), and lead (Pb)were the metals examined. Soil analysis also was carried out for the same elements. The tissues and bones of the fishes were separated before further analysis was made. Drying process technique was used to determine the moisture content for all samples at 80°C for 24 hours. Water content ranged between 70 & 77%. Triplicate samples were evaluated by using Atomic Absorption Spectrophotometer (AAS) to find out heavy metals concentration. Oven and Teflon beakers were used to fully digest all solid samples at 120oC for 3 hours. Highest readings of Zn, Ni and Pb were found in the fish bone for the samples collected from both mentioned locations. However, different pattern was noticed for Cu where higher values were found in the tissues for the same samples. Values of Pb in the tissues were higher than the acceptable value in edible fish by Food and Agriculture Organization (FAO); 1 ppm and Malaysian Food Act (MFR) & World Health Organization (WHO); 2 ppm, whereas values of Cu, Zn were in the acceptable range set by the same organizations. No values recommended for Ni by MFR. In general heavy metals in the bones and tissues from both locations can be sorted in descending order as follows; Pb>Zn>Cu>Ni. Soil samples collected from both locations showed different pattern where high concentration was found for Zn followed by Pb then Cu and Ni. Moreover analysis for soil samples collected from Paka River showed higher content for all elements compared to Kijal. More investigation is needed to clarify whether this contamination is solely from industry or due to geology of the area.
Źródło:
Civil and Environmental Engineering Reports; 2022, 32, 4; 270--281
2080-5187
2450-8594
Pojawia się w:
Civil and Environmental Engineering Reports
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Carbon emissions, energy use, gross domestic product and total population in China
Autorzy:
Ahmad, M.
Hengyi, H.
Rahman, Z. U.
Khan, Z. U.
Khan, S.
Khan, Z.
Powiązania:
https://bibliotekanauki.pl/articles/96260.pdf
Data publikacji:
2018
Wydawca:
Fundacja Ekonomistów Środowiska i Zasobów Naturalnych
Tematy:
energy consumption
carbon emission
GDP
Granger causality
ARDL
EKC
zużycie energii
emisja dwutlenku węgla
PKB
przyczynowość w sensie Grangera
Opis:
The current study explores the impact of energy consumption, total population, gross domestic product on carbon emissions by utilizing time series data of 1971-2013 for China. Earlier studies concentrated on testing the present form of an environmental Kuznets curve not taking total population in a model. Specifically, this study focuses on analyzing the long run existence of environmental Kuznets curve. The methodology of auto regressive distributed lag model is utilized. The quadratic linkage between national income and emissions of carbon have been detected, confirming the presence of long run linkage between quadratic national income and emissions of carbon. Granger causality test divulge one-way causality between gross domestic product and carbon emissions. The empirical findings also reveal that the energy use and national income are important factors of carbon emanations in the long run. Total population has an insignificant positive influence on emissions of carbon. It is suggested that government should focus to extract that substitute sources of energy which is more environmental friendly.
Źródło:
Ekonomia i Środowisko; 2018, 2; 32-44
0867-8898
Pojawia się w:
Ekonomia i Środowisko
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Demarcation energy properties of regenerated fiber Bragg grating sensors in few-mode fibers
Autorzy:
Mohd Nazal, N. A.
Lai, M.-H.
Lim, K.-S.
Gunawardena, D. S.
Chong, W.-Y.
Yang, H.-Z.
Ahmad, H.
Powiązania:
https://bibliotekanauki.pl/articles/174756.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
regenerated fiber Bragg grating
thermal regeneration
thermal decay
few-mode fibers
Opis:
In this work, thermal regeneration of fiber Bragg gratings inscribed in single-mode fibers, two-mode step index fibers and four-mode step index fibers is performed, where the single-mode fibers are used as the reference in the analysis. Specifically, we investigate the behavior of the thermal decay, recovery and eventually the permanent erasure of the gratings in the temperature range from 25 to 1300°C. In the domain of demarcation energy, the thermal responses of the gratings can be normalized and they share similar characteristic curves despite the different temperature ramping rates used in the annealing treatment. It is found that the demarcation energy at the regeneration point and the attempt-to-escape frequency for each grating can be associated with the confinement factors of the fibers. The finding in this work has provided a new insight in the manufacture of regenerated fiber Bragg grating sensors by using few-mode fibers for multiparameter sensing in high temperature environments.
Źródło:
Optica Applicata; 2018, 48, 2; 263-271
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Deposition of a polymeric porous superhydrophobic thin layer on the surface of poly(vinylidenefluoride) hollow fiber membrane
Autorzy:
Ahmad, A. L.
Mohammed, H. N.
Ooi, B. S.
Leo, C. P.
Powiązania:
https://bibliotekanauki.pl/articles/778912.pdf
Data publikacji:
2013
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
Superhydrophobic layer
PVDF
Gas-liquid contactor
CO2
porous
Opis:
Porous superhydrophobic layer of low-density polyethylene (LDPE) was created by a simple approach on the Poly(vinylidenefluoride) (PVDF) hollow fiber membranes. Acetone and ethanol mixtures with different volume ratios were used as the non-solvent on the coating surface. A 5:1 (v/v) acetone/ethanol ratio provided a porous surface with a 152° ± 3.2 water contact angle. The high contact angle could reduce membrane wettability for better carbon dioxide capture when the membrane was used as gas-liquid contactor in absorption processes. To assess the effect of the created superhydrophobic layer, the pristine and modified membranes were tested in a CO2 absorption system for ten days. The results revealed that the absorption flux in the modified membrane was higher than that of pristine membrane.
Źródło:
Polish Journal of Chemical Technology; 2013, 15, 3; 1-6
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Driver performance through the yellow phase using video cameras at urban signalized intersections
Autorzy:
Al-Mistarehi, Bara’ W.
Alomari, Ahmad H.
Obaidat, Mohammed T.
Al-Jammal, Areen A.
Powiązania:
https://bibliotekanauki.pl/articles/2203849.pdf
Data publikacji:
2021
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
driver behavior
signalized intersections
red light running
yellow phase
zachowanie kierowcy
skrzyżowanie z sygnalizacją
przejazd na czerwonym świetle
żółta faza
Opis:
The main objective of this research is to examine the influencing parameters of driver performance through the yellow phase at urban signalized intersections with and without red-light running (RLR) cameras. Data were collected to include the intersection type, vehicle type, turning movement type, whether the vehicle position is in a platoon or not, presence of RLR cameras, green light flash devices, pedestrians, and pavement markings. A total of 2168 driver observations were extracted. Only 33.3% of the drivers stopped before the stop line, 59% of the drivers passed the intersection through the yellow phase, and 7% of the drivers committed RLR violations. The results showed that drivers were more likely to stop before the stop line through the yellow phase at locations with RLR cameras, green light flash devices, pavement markings, where pedestrians were present, and at a four-leg intersection. Chi-square tests indicated that all parameters had a significant impact on driver performance, except for the type of turning movement.
Źródło:
Transport Problems; 2021, 16, 1; 51--64
1896-0596
2300-861X
Pojawia się w:
Transport Problems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dye removal from textile waste water using potato starch : parametric optimization using Taguchi design of experiments
Autorzy:
Ahmad, S. W.
Zafar, M. S.
Ahmad, S.
Mohsin, M.
Qutab, H. G.
Powiązania:
https://bibliotekanauki.pl/articles/204634.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
optimization
potato starch
Taguchi method
spent dye
Opis:
Typical textile waste water contains a high concentration of spent dye that can pose serious destructive impact on aquatic environment. Therefore, treatment of textile industry effluents is strictly imposed by the relevant government authorities and environmental protection agencies. During present studies, spent dye was removed using potato starch, an environmental friendly, biodegradable and cost effective coagulant, through coagulation/flocculation process. Analysis of variance (ANOVA) was performed that indicated the interaction of process parameters. It was observed that the interaction of temperature, pH and coagulant dosage were the most significant parameters that can affect the coagulation/flocculation process. So, temperature, pH and coagulant dosage were optimized by Taguchi optimization technique. The results indicated that maximum dye (about 27%) was removed when temperature, pH and coagulant dosage were kept at 55°C, 10 and 0.5% (w/v), respectively.
Źródło:
Archives of Environmental Protection; 2018, 44, 2; 26-31
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Equilibrium, kinetics and thermodynamic study of the adsorptive removal of methylene blue from industrial wastewater by white cedar sawdust
Autorzy:
Gardazi, Syed Mubashar H.
Shah, Jehanzeb Ali
Ashfaq, Tayyab
Sherazi, Tauqir A.
Ali, Muhammad Arif
Pervez, Arshid
Rashid, Naim
Iqbal, Javed
Amin, Bilal Ahmad Zafar
Bilal, Muhammad
Powiązania:
https://bibliotekanauki.pl/articles/207373.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
methylene blue
industrial wastewater
white cedar sawdust
WCS
dye adsorption
błękit metylenowy
ścieki przemysłowe
trociny białego cedru
adsorpcja barwników
Opis:
The study evaluated the adsorption potential of white cedar sawdust (WCS) for dye removal. WCS was chosen from five preferred, abundant waste biomasses from Pakistan. Various parameters such as contact time, adsorbent dose, dye concentration, pH, and particle size were optimized for methylene blue (MB) dye adsorption. The adsorbent was characterized by FTIR, SEM, EDX and BET analyses. The surface area of the adsorbent was 1.43 m2·g-1 and pore volume was 0.000687 cm3·g-1. The adsorption data best fitted the isotherm models of Langmuir, Temkin, Dubinin–Radushkevich, and Freundlich. The maximum experimental adsorption capacity obtained was 55.15 mg·g-1, which was in close agreement to the calculated adsorption capacity. Fitness of the pseudo-second order kinetics suggested chemisorption as the rate-limiting step. Thermodynamic study for adsorption was carried out to evaluate the Gibbs free energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°). The negative values ΔG° at the examined temperature range confirmed the spontaneous adsorption of MB onto WCS.
Źródło:
Environment Protection Engineering; 2019, 45, 3; 5-22
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental Analysis of Titanium Dioxide Synthesis from Synthetic Rutile Waste using a Moderate Acid Concentration and Temperature
Autorzy:
Ahmad Mukifza, H.
Awang, H.
Yusof, S.
Farid, E.
Powiązania:
https://bibliotekanauki.pl/articles/1031724.pdf
Data publikacji:
2017-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
synthetic rutile
titanium dioxide
caustic hydrothermal
sodium titanate
Opis:
The present study is to clarify the present influences of acid concentration and temperature of caustic hydrothermal method on extracting the titanium dioxide (TiO₂) from synthetic rutile waste. In this experimental work, the caustic hydrothermal method comprises two processes: a decomposition and the sulphate process. The extracted titanium is characterized by using a electron dispersive X-ray spectroscopy to specify its chemical composition, field emission scanning electron microscope to determine the morphology and particle size, and lastly it is the X-ray diffraction to analyse the crystallinity of extracted titanium. In this study, we found that both acid concentration and temperature affected the TiO₂ growth while the calcination process could improve the crystallinity of extracted titanium.
Źródło:
Acta Physica Polonica A; 2017, 132, 3; 833-835
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Extraction, Chemical Composition and Antidiabetic Potential of Crude Polysaccharides from Centella asiatica (L.) Urban
Autorzy:
Li, Meng
Shahid, Muhammad
Zhang, Xiaobin
Law, Douglas
Mackeen, Mukram M.
Teh, Arnida H.
Najm, Ahmad A.
Fazry, Shazrul
Othman, Babul A.
Powiązania:
https://bibliotekanauki.pl/articles/31341117.pdf
Data publikacji:
2024-05-24
Wydawca:
Instytut Rozrodu Zwierząt i Badań Żywności Polskiej Akademii Nauk w Olsztynie
Tematy:
alcohol insoluble residue
antidiabetic
mineral elements
monosaccharide composition
response surface methodology
Opis:
The global prevalence of diabetes mellitus (DM) is escalating, posing a significant challenge to human healthcare systems. In the present study, mineral and monosaccharide compositions, and antidiabetic potential of polysaccharide fractions separated from Centella asiatica (L.) leaves (CAL) were assessed. Initial single-factor experiments identified key extraction parameters, further optimized through response surface methodology (RSM) with optimal conditions determined as a liquid-to-solid ratio of 24.43:1 (mL/g), extraction time of 60.76 min, and a temperature of 83.31℃. Alcohol insoluble residue (AIR) extraction yielded three crude polysaccharide fractions (P50, P70, and P90). P50 was obtained with the highest yield (14.31%) and exhibited the highest content of total sugars and uronic acids (68.01 and 24.28 g/100 g, respectively). Calcium, magnesium, and manganese were dominant minerals in P50 and P70. Monosaccharide composition analysis via high-performance liquid chromatography (HPLC) demonstrated enrichment of galacturonic acid, galactose, and arabinose in P50 and P70. Furthermore, both fractions (P50 and P70) exhibited dose-dependent inhibitory effects on α-amylase and α-glucosidase. At 5 mg/mL, P50 caused 68.3% α-amylase inhibition and 62.3% α-glucosidase inhibition, while P70 triggered 46.8% and 34.1% inhibition, respectively. In conclusion, this study is the first to provide valuable insights into optimizing CAL extraction conditions. Potential utilization of polysaccharide fractions obtained from CAL as components for formulating functional foods can be explored in the future.
Źródło:
Polish Journal of Food and Nutrition Sciences; 2024, 74, 2; 177-187
1230-0322
2083-6007
Pojawia się w:
Polish Journal of Food and Nutrition Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Facies and diagenetic evolution of the Bathonian-Oxfordian mixed siliciclastic-carbonate sediments of the Habo Dome, Kachchh Basin, India
Autorzy:
Ahmad, A. H. M.
Irshad, R.
Bhat, G. M.
Powiązania:
https://bibliotekanauki.pl/articles/2077322.pdf
Data publikacji:
2015
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
facies
diagenetic evolution
Habo Dome
Kachchh Basin
India
facja
diageneza
ewolucja diagenetyczna
Kachchh
Indie
Opis:
This paper examines the depositional environment and diagenetic aspects of the exposed Patcham and Chari formation within the Habo Dome. The Patcham Formation is represented by the Black Limestone Member. The Chari Formation is represented by two distinct sedimentary successions: (i) shale and carbonates, and (ii) coarse clastics. The paper describes eleven lithofacies from these successions. The depositional framework constituents of these facies have been greatly modified by diagenetic evolution through time. Two main depositional environments, i.e. foreshore intertidal and shoreface (subtidal), have dominated during their deposition. The diagenetic signatures observed within these sediments suggest early or syndepositional changes in marine phreatic and burial environments. Two phases of early mechanical compaction have largely governed porosity evolution within the limestone facies. Micritization of the allochems was caused by endolithic algae prevalent within the restricted lagoon environments with stagnant marine phreatic zone conditions. Random dissolution of microcrystalline grains has created vugs with patchy distribution reflecting neomorphism within the meteoric vadose zone. The types of cements within the sandstone facies include silica, calcite, and its replacement by Fe-calcite cement. The sandstones were deposited in a relatively low energy environment below storm wave base. The depositional conditions have controlled the early diagenesis of the sandstones which in turn have influenced their burial diagenesis.
Źródło:
Volumina Jurassica; 2015, 13, 1; 83--104
1896-7876
1731-3708
Pojawia się w:
Volumina Jurassica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Granulometric and facies analysis of Middle–Upper Jurassic rocks of Ler Dome, Kachchh, western India: an attempt to reconstruct the depositional environment
Autorzy:
Ghaznavi, Asma A.
Quasim, M. A.
Ahmad, A. H. M.
Ghosh, Sumit K.
Powiązania:
https://bibliotekanauki.pl/articles/94565.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
grain size analysis
hydrodynamic conditions
microtexture
sedimentation
marine environment
analiza wielkości ziarna
warunki hydrodynamiczne
mikrotekstura
sedymentacja
środowisko morskie
Opis:
Grain size analysis is an important sedimentological tool used to unravel hydrodynamic conditions, mode of transportation and deposition of detrital sediments. For the present study, detailed grain size analysis was carried out in order to decipher the palaeodepositional environment of Middle–Upper Jurassic rocks of the Ler Dome (Kachchh, western India), which is further reinforced by facies analysis. Microtextures were identified as grooves, straight steps and V-shaped pits, curved steps and solution pits suggesting the predominance of chemical solution activity. Grain size statistical parameters (Graphic and Moment parameters) were used to document depositional processes, sedimentation mechanisms and conditions of hydrodynamic energy, as well as to discriminate between various depositional environments. The grain size parameters show that most of the sandstones are medium- to coarse-grained, moderately to well sorted, strongly fine skewed to fine skewed and mesokurtic to platykurtic in nature. The abundance of medium- to coarse-grained sandstones indicates fluctuating energy levels of the deposition medium and sediment type of the source area. The bivariate plots show that the samples are mostly grouped, except for some samples that show a scattered trend, which is either due to a mixture of two modes in equal proportion in bimodal sediments or good sorting in unimodal sediments. The linear discriminant function analysis is predominantly indicative of turbidity current deposits under shallow-marine conditions. The C-M plots indicate that the sediments formed mainly by rolling to bottom suspension and rolling condition in a beach subenvironment. Log probability curves show that the mixing between the suspension and saltation populations is related to variable energy conditions.
Źródło:
Geologos; 2019, 25, 1; 51-73
1426-8981
2080-6574
Pojawia się w:
Geologos
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 35

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