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Number of results: 10
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Abstract

Applying new technologies basing on coal utilization demands precise identification of coal-bed composition. It is suggested, that such possibility is enabled by coal-bed logging with use of - adjusted to this aim - microlithotype analysis. Modification of this research method relies on ten-fold augmentation of 20 point grid size dimensions - up to 500 x 500 [...]. Maceral associations - as identified duringmicroscope observations - are placed in computer database according to their localization in logging. This allows for later graphic interpretation - microlithotype profile drawing. 13 associations has been educed in description, in majority being consistent with commonly used microlithotypes. However, a few changes has been introduced: in description of vitrite, telovitrite, macroscopically recognized in logging as vitrine layers, has been distinguished, as well as detro-gelo-vitrite, macroscopically recognized in logging as durain, while within bimaceralic microlithotypes there has been distinguished: vitrinertite (W), vitrinertite (I), clarite (W), clarite (I), durite (L), durite (I), all on the basis of dominant ingredient named in parenthesis. Accepted research methodology enables precise characteristics of petrographic variation within coal-bed logging. This allows especially to describe variation within dull coal (durain). Basing on research results, it is suggested that the biggest share in seam composition belongs to duroclarite - 23.8%, then vitrite - 18.7% and clarodurite - 17.6%, lower share of few percent belongs to: vitrinertite (I), vitrinertite (W), inertite, clarite (W), vitrinertoliptite, durite (I), durite (L), while both liptite and clarite (L) are less than one percent . Sequence of following microlithotypes also illustrate facies variation, what allows interpretation of environments of peat deposition in paleo-peat bog 116/2. Dominating percentage in log belongs to Forest Moor facies - 33.5%, while the lowest is Forest Terrestial Moor - 12.5%.

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Authors and Affiliations

Jacek Misiak
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Abstract

The Bogdanka coal mine, the only currently operating mine in the Lublin Coal Basin (LCB),

extracts coal from the Upper Carboniferous formations of the LCB. The average sulfur content in

the No. 385/2 seam is 0.98%, while in the case of the No. 391 seam it is slightly higher and amounts

to 1.15%. The iron sulfides (pyrite and marcasite) in bituminous coal seams form macroscopically

visible massive, vein, and dispersed forms. A microscopic examination has confirmed their complex

structure. Massive forms contain euhedral crystals and framboids. The sulfide aggregations are often

associated with a halo of dispersed veins and framboids. Pyrite and marcasite often fill the fusinite

cells. Framboids are highly variable when it comes to their size and the degree of compaction within

the carbonaceous matter. Their large aggregations form polyframboids. The cracks are often filled

with crystalline accumulations of iron sulfides (octaedric crystals). The Wavelenth Dispersive Spectrometry

(WDS) microanalysis allowed the chemical composition of sulfides in coal samples from the

examined depoists to be analyzed. It has been shown that they are dominated by iron sulfides FeS2 –

pyrite and marcasite. The examined sulfides contain small admixtures of Pb, Hg, Zn, Cu, Ag, Sb, Co,

Ni, As, and Cd. When it comes to the examined admixtures, the highest concentration of up to 0.24%,

is observed for As. In addition, small amounts of galena, siderite, and barite have also been found in

the examined coal samples. The amounts of the critical elements in the examined samples do not allow

for their economically justified exploitation. Higher concentrations of these elements can be found in

the ashes resulting from the combustion process.

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Authors and Affiliations

Barbara Bielowicz
Jacek Misiak
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Abstract

The earliest studies of the Moon consisted of observations from Earth and meteorites containing lunar material. As technology progressed, the observations were made using remote sensing techniques. The next stage of the Moon reconnaissance consisted of unmanned flights, and later manned flights, with the help of which, in-situ tests were performed. The obtained materials enable the formulation of conclusions both about the geological structure and the mineral resources of the moon. The latest maps provided by the United States Geological Survey (USGS) and NASA Planetary Data System (PDS) enable a detailed analysis of the geological structure of the moon. Since they are available in shapefile format for QGIS and ArcGIS software, they can be freely modified and processed. On the basis of these, it is possible to analyze the complexity of the geological structure of the moon, especially with regard to the structure of its substrate and the surface covered with craters. Data obtained from the observation of the Moon with the use of research satellites and research carried out during landings related to the collection of samples enabled the formulation of conclusions about the raw materials present there. These raw materials are related to the surface layer of the so-called regolith, the recognition of which is relatively good because it is based not only on remote studies but also on the basis of collected samples. Additionally, there are indications of the possible presence of mineral resources related to the substrate, but its recognition is relatively poor because it is based on remote and geophysical surveys. The presented analysis shows that the Moon has such minerals as rare earth elements (REE) and Th and U found in the KREEP area. Fe and Ti are found to be in basaltic lava flows occurring in the mares and aluminum, silicon and Helium-3 occur in the regolith.
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Authors and Affiliations

Jacek Misiak
1
ORCID: ORCID

  1. AGH University of Science and Technology, Faculty of Geology, Geophysics and Environment Protection, Kraków, Poland
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Abstract

The new boreholes drilled between 2009 and 2012 enabled a detailed exploration of the profile of the Kraków sandstone series in the Dąb area between the “Sobieski” and “Janina” mining plants, USCB (Upper Silesian Coal Basin). The core from the No. 111. bituminous coal seam was selected for further analysis. 30 intervals corresponding to the defined lithotypes were separated in the seam with a thickness of 116.8 cm. The thickness of lithotypes ranges from 10 mm to 89 mm. A microprofile of the examined seam was made using the modified method of determining microlithotypes. A quantitative determination of the maceral composition was performed for each interval corresponding to the separated lithotypes. This allowed petrographic and facies characteristics of the seam to be determined. Its lower part is dominated by lithotypes with a large share of bright coal – vitrain coal. This section of the profile was formed under conditions of a strongly flooded wet forest swamp. In the upper section of the seam, a higher macroscopic share of dull coal – durain was observed. The microscopic analysis has shown that the conditions dominant during the formation of this section were typical for swamp forest peats. New technologies also require expanding knowledge about the structure of coal seams. This is only possible with a detailed profiling of the coal seam on a macro scale combined with micro-profiling and a detailed petrographic description of the isolated lithotypes. This methodology is also useful in the facies analysis of bituminous coal seams.

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Authors and Affiliations

Jacek Misiak
ORCID: ORCID
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Abstract

The quality of coal has been analyzed basing on the data from geological exploration and chemical – geological analyses of coal carried out on the samples obtained from the boreholes and mining pits. The operated coal seams indexed as 382 and 385/2 reveals the changeable morphology due to the thickness of carbon shoals and stent intergrowths. The other parameters, such as the ash content or the calorific value are strongly linked with the non-coal rock interlayers, which presence causes the decrease in the calorific value and increase in the amount of after-burning ash. These parameters are less dependable on the sedimentation environment of the coal formation material. The content of total sulfur in the analyzed seams does not show any link with the values of the parameters analyzed before. The total sulfur is made up from sulphide gathered in coal and sulphates deriving from the decomposition of plants and supplied by deposit waters in different phases of coal seam formation. The obtained results could be useful in the reconnaissance of the prospective seams lying below the currently exploited ones (e.g. 389) and the seams in the neighboring areas.

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Authors and Affiliations

Jacek Misiak
ORCID: ORCID
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Abstract

The subject of the study was the No. 116/2 coal seam belonging to the Cracow Sandstone Series of the Upper Silesian Coal Basin. Reflectograms of the samples taking into account all the vitrinite group macerals present in the coal were recorded for Δ Ro close to the standard deviation and in the standard range. A careful analysis of vitrinite reflectograms reveals the presence of three or four clearly distinguished peaks. When assessing the rank of coal, only the main maximum, peak No. 4, was considered to be significant. Measurements of the average reflectance of collotelinite were made only on the vitrinite surfaces with a thickness of more than 1 mm. Only two maxima were revealed on detailed reflectograms. These maxima correlate with the peaks marked as No. 3 and 4 in the sample reflectograms taking into account all the vitrinite group macerals. The C daf content in the tested coal from the Janina coal mine is between 75.9 and 77.5 wt%, while for vitrain, it ranges from 71.1 to 75.5 wt%. This relationship is an exponential regression with a correlation coefficient of r = 0.95h and can be approximated by a linear correlation of r = 0.94. The correlation strength between the volatile matter content and the coefficient of average reflectance in the vitrinite of the tested coal was also examined. The statistically significant correlation is strong, which is expressed by the exponential correlation coefficient “r” being close to 0.99 and its linear approximation with the correlation coefficient r = 0.98. However, no correlation was found between the measured reflectance values and the GI coefficient calculated for the examined samples.
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Authors and Affiliations

Jacek Misiak
1
ORCID: ORCID

  1. AGH University of Kraków, Faculty of Geology, Geophysics and Environment Protection, Poland

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