MGU
Geology and exploration of mineral resources
Numerous differences in the petrography and organic geochemistry of two Tertiary, low rank coal deposits of Bulgaria, formed within comparable depositional environments, are outlined. Different floral assemblages are indicated as the main... more
Numerous differences in the petrography and organic geochemistry of two Tertiary, low rank coal deposits of Bulgaria, formed within comparable depositional environments, are outlined. Different floral assemblages are indicated as the main sources of organic matter. For the Eocene Bourgas sub-bituminous coals a warm climate plant community dominated by angiosperms is reflected in the biomarker composition, whereas a coniferous flora was the main source of the resinous organic matter of the Miocene Maritza-East lignite. The results are in agreement with palaeobotanical data. These differences in the peat forming vegetation of the Paleogene compared to the Neogene of Bulgaria are attributed to decreasing temperature during the Tertiary. The abundance of resinous compounds relative to lipids from plant waxes (long chain n-alkanes), as well as the preservation of plant tissue, are mainly controlled by gymnosperm/angiosperm ratios.Pristane/phytane and diasterenes/sterenes ratios reflect variations in redox conditions and the pH of the depositional environments, caused by eustatic sea level changes, freshwater inflow, or varying (ground)water table. Changing Eh and pH values are associated with differences in microbial activity controlling the extent of gelification of plant tissue. Bacteria most probably contributed to the aromatisation of triterpenoids in the mire.Enhanced thermal maturation of organic matter during diagenesis is reflected in higher contents of n-alkanes and the presence of alkyl naphthalenes in the Bourgas coals. Alkyl naphthalenes are thought to have been formed from pentacyclic triterpenoids rather than from resinous compounds.
Coal petrologic and mineralogic investigations, along with proximate and Rock-Eval pyrolysis, were performed on samples from a borehole in the center of the Karlovo basin in order to determine the depositional environment of the Karlovo... more
Coal petrologic and mineralogic investigations, along with proximate and Rock-Eval pyrolysis, were performed on samples from a borehole in the center of the Karlovo basin in order to determine the depositional environment of the Karlovo lignite, which formed during the transgressive stage of a tectonic graben. Several thin coaly layers represent the transition from a fluvio-deltaic to a lacustrine environment, but only the uppermost lignite seam, which is about 10-m thick, is considered (sub-) economic. The latter is characterized by medium to high ash yields and low sulfur contents.The coal formed in a rheotrophic, low-lying mire near a freshwater lake with low pH value. The acid environment resulted in low bacterial activity, low gelification, and low sulfur contents. Alumosilicates were altered to kaolinite, another consequence of the acidic peat water.During peat accumulation areas with open water existed in the central basin. Alginite-rich sapropelic sediments with (acidophilic) diatoms accumulated in these anaerobic ponds. Apart from the basin center, xylitic coal indicates a vegetation rich in decay resistant conifers (swamp forest). Relatively dry conditions were established during later peat-forming stages. This is indicated by lower ash yields and increased contents of fusinite and fungal remains. Peat accumulation was terminated by a major flooding event and the establishment of a lake.
The aim of the present study is to provide additional information about the properties and depositional environment of the Kipra lignite seam, which was deposited during the regressive stage of development of the Maritza-West basin.... more
The aim of the present study is to provide additional information about the properties and depositional environment of the Kipra lignite seam, which was deposited during the regressive stage of development of the Maritza-West basin. Petrographical and mineralogical data, along with ash yields and sulphur contents of 24 samples from a seam profile, have been used to study the vertical variation of the depositional settings during peat accumulation and subsequent coalification.The Kipra lignite is characterized by high ash yields and sulphur contents. It formed in a rheotrophic, low-lying mire with alkaline pH value. Vegetation with low preservation potential dominated within the palaeomire. During peat formation, frequent changes of the water level controlled the depositional environment. During the deposition of units 1 and 2, high water energy caused the transportation of high amounts of inorganic material into the mire, resulting in the formation of weakly gelified mineral-rich lignite. The organic matter from units 3 and 4 is characterized by enhanced gelification, which probably reflects the decreasing energy of the system. Good positive correlation between sulphur contents and the GI values was established in units 4, indicating that the gelification of the tissues was probably mainly controlled by the bacterial activity. In contrast, the gelification of the samples from unit 3 of the Kipra seam was probably governed by the redox conditions. The organic matter deposited under relatively wet conditions, in which the thermal and oxidative destruction of the tissues, was limited.A variety of major, minor and accessory minerals are present in Maritza-West lignite. The mineral composition is dominated mainly by pyrite, gypsum and calcite, and to a lesser extent limonite, quartz, kaolinite, montmorillonite, illite, chlorite and plagioclase. Jarosite, hematite, halloysite, mica, K-feldspar, aragonite, siderite, and dolomite were also determined in very low concentrations. These minerals formed syngenetically and epigenetically. The syngenetic stage is characterized mainly by the formation of pyrite, carbonates, silicates and sulphates, whereas the Fe-oxyhydroxides, partially the carbonates and almost all silicates are of detrital origin. During the epigenetic stage, carbonates, sulphates, clay minerals, pyrite, and Fe-oxyhydroxides were formed. Alteration products like gypsum, jarosite, limonite, chlorite, kaolinite, illite, mica, and calcite were generated due to the transformation of detrital and authigenic minerals.
À. Çäðàâêîâ, É. Êîðòåíñêè. 2004. Ìàöåðàëåí ñúñòàâ è óñëîâèÿ íà îòëàãàíå íà âúãëèùàòà îò Áåëîáðåaeêèÿ áàñåéí, Áúëãàðèÿ. -Ñïèñ. Áúëã. ãåîë. ä-âî, 65, 1-3, 157-166. Ðåçþìå. Áåëîáðåaeêèÿò âúãëèùåí áàñåéí å ðàçïîëîaeåí â Çàïàäíà Áúëãàðèÿ â... more
À. Çäðàâêîâ, É. Êîðòåíñêè. 2004. Ìàöåðàëåí ñúñòàâ è óñëîâèÿ íà îòëàãàíå íà âúãëèùàòà îò Áåëîáðåaeêèÿ áàñåéí, Áúëãàðèÿ. -Ñïèñ. Áúëã. ãåîë. ä-âî, 65, 1-3, 157-166. Ðåçþìå. Áåëîáðåaeêèÿò âúãëèùåí áàñåéí å ðàçïîëîaeåí â Çàïàäíà Áúëãàðèÿ â ðàìêèòå íà Áóðåëñêàòà ðàçëîìíà çîíà. Âúãëåíîñíèòå ñåäèìåíòè ñà ïðåäñòàâåíè îò àëåâðîëèòè, ïåñú÷ëèâè è êàðáîíàòíè ãëèíè è äî ïåò âúãëèùíè ïëàñòà, îò êîèòî ñàìî åäèí èìà ãîëÿìà äåáåëèíà (äî 35 m) è å ðàçïðîñòðàíåí â öåëèÿ áàñåéí. Âúãëèùàòà ñà èçãðàäåíè îò ðàçëè÷íî ãîëåìè ñâåòëî-äî òúìíîêàôÿâè êñèëèòíè îñòàíêè, âêëþ÷åíè â òúìíà ìàòîâà îñíîâíà ìàñà. Ñ èçâúðøåíèòå ïåòðîãðàôñêè èçñëåäâàíèÿ áå óñòàíîâåíî, ÷å âúãëèùàòà ñå îòëè÷àâàò ñ ãîëÿìî ìàöåðàëíî ðàçíîîáðàçèå, êîåòî, ñ èçêëþ÷åíèå íà äåòðîãåëèíèò è âòîðè÷íèòå ëèïîèäíè ìàöåðàëè áèòóìèíèò è åêññóäàòèíèò, âêëþ÷âà âñè÷êè îñòàíàëè ìàöåðàëè. Ìàöåðàëíèÿò àíàëèç ïîêàçâà, ÷å ìèêðîêîìïîíåíòèòå îò ãðóïà õóìèíèò ïðåäñòàâëÿâàò îñíîâíèÿ ãðàäèâåí åëåìåíò íà âúãëèùàòà, êàòî ñúñòàâëÿâàò äî 91 îáåìíè ïðîöåíòà. Ñúäúðaeàíèåòî íà ìàöåðàëè îò ãðóïà ëèïòèíèò äîñòèãà äî 8%, êàòî ïðåîáëàäàâàò ìèêðîñïîðèíèò, ñóáåðèíèò è ðåçèíèò. Èíåðòèíèòîâèòå ìàöåðàëè ñà äèàãíîñòèöèðàíè â ìèíèìàëíè êîëè÷åñòâà. Èç÷èñëåíè ñà èíäåêñèòå íà òîðôåíèÿ ôàöèåñ, êîèòî â ñú÷åòàíèå ñ ïåòðîëîaeêèòå îñîáåíîñòè íà ìèêðîêîìïîíåíòèòå ïîêàçâàò, ÷å âúãëèùàòà ñà îáðàçóâàíè â ëèìíî-òåëìàòè÷íî ðåîòðîôíî îâîäíåíî áëàòî, õàðàêòåðèçèðàùî ñå ñ èíòåíçèâåí ìèíåðàëåí ïðèòîê. Âúç îñíîâà íà óñòàíîâåíèòå ïîêàçàòåëè (îòðàaeàòåëíà ñïîñîáíîñò, ñúäúðaeàíèå íà îðãàíè÷åí âúãëåðîä, òåìïåðàòóðà íà ìàêñèìàëåí äîáèâ íà âúãëåâîäîðîäè) å ïîòâúðäåí íèñêèÿò ðàíã íà âúãëèùàòà, êîèòî òðÿáâà äà ñå ïðèåìàò êàòî ïðåõîä îò òîðô êúì ëèãíèòè.
Compositions of Balsha lignite, Sofia coal-bearing basin, Bulgaria and carbonaceous shales are studied by petrological and geochemical proxies. The macropetrographic characteristic of profiles is relatively constant. The lignite is... more
Compositions of Balsha lignite, Sofia coal-bearing basin, Bulgaria and carbonaceous shales are studied by petrological and geochemical proxies. The macropetrographic characteristic of profiles is relatively constant. The lignite is generally composed of dull matrix coal containing significant amounts of xylite fragments. The typical microscopic constituents of the lignite are the ulminite, and less frequently textinite lenses, scattered within attrinitic groundmass. The maceral composition of the organic matter in carbonaceous shales does not differ significantly from that of the lignite samples. Biomarker assemblages of the extractable portions are determined by gas chromatography-mass spectrometry. Additional information for the compositions of residues after extractions is obtained by TMAH thermally assisted hydrolysis/methylation. Petrographic contents, lipid assemblage and TMAH thermally assisted hydrolysis/methylation data imply that the original peat bog is formed in fresh-water forest swamp preferably composed by gymnosperms. Polar diterpenoids argue for Cupressaceae s.l., Taxodiaceae as the most probable vegetation. For one of the profiles appreciable angiosperm rich herbaceous-type flora contribution is assumed. Polar oleanane triterepenoids and their aromatized derivatives argue for angiosperm input. The relevance of A-norfriedel-8-en-10-one/friedelin ratio for groundwater level appraisal is discussed. It admits long period of high water level in the paleomire. High content of vanillyl structures and subordinated presence of syringyl units in products of TMAH thermally assisted hydrolysis/methylation are hint for Gymnospermae input in the paleoswamp and Angiospermae contribution to one of the profiles. Cinnamyl phenolic units, indicating non-woody angiosperm vegetation presence, are registered as well. Flavonoids in products are considered as taxonomic markers of Cupressaceae plants in the paleoswamp.
- by Maya Stefanova and +1
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- Geology, Coal Geology
This paper presents results of monitoring research in the soils close to Thermal Power Plant “Bobov Dol”. The aim is to determine the changes in soil sorption capacity and soil acidity.The data obtained from research confirm that typical... more
This paper presents results of monitoring research in the soils close to Thermal Power Plant “Bobov Dol”. The aim is to determine the changes in soil sorption capacity and soil acidity.The data obtained from research confirm that typical for the region Luvisols have good sorption properties. Reclaimed Technolsols show low soil sorption capacity. The results shows that there is no significant change in the chemical properties in surface horizon of the soils close to TPP Bobov Dol, despite long period of operation and deposition of coal ash.
- by Ivona Nikova and +3
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The article dealt with rem ote sensing satellite im ages m ade in the area of therm al power plant Bobov Dol. The spectral reflectance characteristics of different rocks and m inerals were studied using m ultispectral satellite im ages.... more
The article dealt with rem ote sensing satellite im ages m ade in the area of therm al power plant Bobov Dol. The spectral reflectance characteristics of different rocks and m inerals were studied using m ultispectral satellite im ages. For the classification of ground surface is used a satellite scene, obtained from ASTER (The Advanced Spaceborne Therm al Em ission and Reflectance Radiom eter) instrum ent which is sensor system s with a unique com bination of wide spectral coverage and high spatial resolution. The ASTER instrum ent has three spectral bands in the visible and near-infrared (VNIR), six bands in the short-wave-infrared (SWIR), and five bands in the therm al infrared (TIR) regions respectively. To characterize the landscape features was used Digital Elevation Model (DEM) created with the m ission of space shuttle in February 2000 and known as the SRTM (Shuttle Radar Topography Mission). There have been m aps of the spatial distribution of iron oxides, clay m inerals an...
- by Ivona Nikova and +3
- •
The aim of this study is spatial analysis and assessm ent of the content of As in soils in the area of Bobov Dol Therm olectric power plant. Soil sam ples were taken according to previously selected polygonal network. The sam ple... more
The aim of this study is spatial analysis and assessm ent of the content of As in soils in the area of Bobov Dol Therm olectric power plant. Soil sam ples were taken according to previously selected polygonal network. The sam ple locations ensure evenly cover of the selected area of interest. А preliminary statistical analysis of the data was perform ed in order to evaluate the distribution of As and exclusion of erroneous values. Interpolation of the data was m ade by kriging geostatistical m ethods and variogram m e analysis. The analysis of the variability in the data showed the m ost gradual change of the contents in the east-west direction. Areas with higher contents of As are found то тхе west of the Тherm al power plant.
- by Ivona Nikova and +2
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The paper deals with the content and composition of organic matter of soils polluted with ash from thermal Power Plant “Bobov dol”. coal impurities have impact not only on the amount of total carbon but also on the type of humus. Fine ash... more
The paper deals with the content and composition of organic matter of soils polluted with ash from thermal Power Plant “Bobov dol”. coal impurities have impact not only on the amount of total carbon but also on the type of humus. Fine ash particles are deposited in the northern part of the valley, and they had change the composition of organic acids, where now humic type of humus dominates. the average amount of organic carbon increases in the surface horizon since 1979. it could be considered that this increase is due to 36 years of tPP “Bobov dol” operation.
- by Kalin Rouskov and +2
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- Soil Science
2 "Минпроект ЕАД", София РЕЗЮМЕ. Пети въглищен пласт от Балканския басейн е опробвани с 10 пластови проби. Въглищните аншлиф-брикети са изследвани в отразена бяла и флуорисцентна светлина в маслена имерсия и е измерен показател на... more
2 "Минпроект ЕАД", София РЕЗЮМЕ. Пети въглищен пласт от Балканския басейн е опробвани с 10 пластови проби. Въглищните аншлиф-брикети са изследвани в отразена бяла и флуорисцентна светлина в маслена имерсия и е измерен показател на отражение на хуминита. Чрез технически анализ са определени и останалите класификационни параметри: обща и аналитична влага, пепелно съдържание, добив на летливи вещества, обща сяра и топлината на изгаряне на влажно и на сухо безпепелно гориво. Установен е и индекса на свободното бухване на коксовия остатък. Според определените показатели, съгласно Международната класификация на въглища в пласта въглищата от V пласт са ивичести предимно хумусни от среден ранг А -пербитуминозни със средно качество. Определен е кодът, съгласно Международната кодификационна система -15 0 00 1 12 12 18 35. Ключови думи: черни въглища, мацерали, Международната класификация на въглища в пласта, Международната кодификационна система, Балкански басейн ABSTRACT. The present study is based on 10 whole-coal samples from the V coal seam in Balkan basin. The samples were analyzed using standard microscopy and technological techniques, including reflected white and fluorescent light studies, reflectance measurements, and determination of the total and analystical moisture contents, ash yield, total sulphur contents, volatile matter, and the combustion temperature of the coal. In addition, the index of coke swelling was determined. Based on the results from these investigations and according to the International Classification of In-Seam Coals the coals from the V th seam in Balkan basin can be classified as banded, predominantly humic, intermediate Aperbituminous with intermideate quality. Furthermore, the code according to the International Codification System was determined to be 15 0 00 1 12 12 18 35.
The lignite seam was sampled in ten sections. According to the International In-Seam Coal Classification Gotse Delchev lignite can be classified as metalignite with calorific value -15.86 MJ/kg and huminite reflectance -0.246%. The... more
The lignite seam was sampled in ten sections. According to the International In-Seam Coal Classification Gotse Delchev lignite can be classified as metalignite with calorific value -15.86 MJ/kg and huminite reflectance -0.246%. The petrographic composition is dominated by the huminite group macerals among which detrohuminite (mainly densinite) is prevailing. The contents of liptinite macerals are relatively high (19.5% avg.), mainly due to the presence of detritic liptinite particles. Resinite contents are low, thus suggesting precursor vegetation composed mainly of deciduous trees and herbaceous plants. The inertinite group is represented by funginite and inertodetrinite in very low amounts (0.31% avg.). The ash yield is high which argues for a rheotrophic environment in the ancient peat-mire. The maceral indices point to peat formation in a limnic to telmatic inundated marsh, characterized by frequent changes of the water level.
РЕЗЮМЕ. Опробвани са въглищни пластове от Бобовдолския басейн. Определено е съдържанието на главните елементи във въглищната пепел. Пепелообразуващи елементи са Si, Al, Fe, Ca, S, Mg, Ti и K, тъй като техните концентрации надвишават 0,5%.... more
РЕЗЮМЕ. Опробвани са въглищни пластове от Бобовдолския басейн. Определено е съдържанието на главните елементи във въглищната пепел. Пепелообразуващи елементи са Si, Al, Fe, Ca, S, Mg, Ti и K, тъй като техните концентрации надвишават 0,5%. Количествата на Na, Mn и особено на Р са много малки. Преобладаващ органичен афинитет проявяват Ca, S, Mn и Mg, докато Si, Al, K, Р и Ti са привързани предимно към неорганичното вещество на въглищата. Желязото и натрият са със смесен афинитет. Елементите са групирани в две асоциации: Si-Al-Ti-K и Ca-S-Mg-Mn, обусловени от сходния афинитет на елементите и сходна минерална и органична форма на присъствие. Чрез диаграма на киселинността на средата е определена стойността на рН, която средно е приблизително 4.8. Изчисленият индекс на подхранване на торфеното блато (SI) определя преобладаващо подхранване с теригенен материал от повърхностни води и по-слабо грунтово подхранване. Ключови думи: кафяви въглища, пепелообразуващи елементи, органичен и неорганичен афинитет, киселинност на средата, индекс на подхранване, Бобовдолнски басейн ABSTRACT. The coal seams in Bobov dol basin were samples and the concentration of the major elements in coal ash was determined. The amounts of elements like Si, Al, Fe, Ca, S, Mg, Ti and K are exceeding 0.5%, whereas Na, Mn and P contents are very low. Predominantly organic affinity is characteristic for Ca, S, Mn and Mg. In opposite, Si, Al, K, Р and Ti are mainly connected to the inorganic matter in coal. Iron and Na were having mixed affinity. All elements were grouped in two associations: Si-Al-K-Ti and Ca-S-Mg-Mn, based on their similar behavior and mode of occurrence. The pH conditions during coal formation were determined using a diagram of acidity. The results indicate coal formation in acid conditions, with average pH value of 4.8. The calculated supply index (SI) shows a clear predomination of the terrigenous input from flowing waters over the groundwater supply.
The lignite seam was sampled in ten sections. According to the International In-Seam Coal Classification Gotse Delchev lignite can be classified as metalignite with calorific value -15.86 MJ/kg and huminite reflectance -0.246%. The... more
The lignite seam was sampled in ten sections. According to the International In-Seam Coal Classification Gotse Delchev lignite can be classified as metalignite with calorific value -15.86 MJ/kg and huminite reflectance -0.246%. The petrographic composition is dominated by the huminite group macerals among which detrohuminite (mainly densinite) is prevailing. The contents of liptinite macerals are relatively high (19.5% avg.), mainly due to the presence of detritic liptinite particles. Resinite contents are low, thus suggesting precursor vegetation composed mainly of deciduous trees and herbaceous plants. The inertinite group is represented by funginite and inertodetrinite in very low amounts (0.31% avg.). The ash yield is high which argues for a rheotrophic environment in the ancient peat-mire. The maceral indices point to peat formation in a limnic to telmatic inundated marsh, characterized by frequent changes of the water level.
Petrographic investigations of the Staniantsi lignite were performed on 45 samples using reflected white and fluorescent light. The dominant maceral group was determined to be Huminite with average amount of 84.2%. Textinite, ulminite,... more
Petrographic investigations of the Staniantsi lignite were performed on 45 samples using reflected white and fluorescent light. The dominant maceral group was determined to be Huminite with average amount of 84.2%. Textinite, ulminite, attrinite, gelinite and corpohuminite were detected. The Liptinite maceral group composes about 14.3% of the organic mass, and is represented by most of the individual macerals (i.e. sporinite, cutinite, resinite, suberinite, alginite, fluorinite and liptodetrinite). Char-coal fragments compose only about 1.5% of the organic mass. Fusinite, semifusinite, funginite and inertodetrinite were detected in low amounts. The petrographic investigations revealed a low degree of gelification of Staniantsi lignite. The precursor material is severely degraded and deposited in a sedimentary environment characterized by prolonged periods of high water table.
The lignite seam was sampled in ten sections. According to the International In-Seam Coal Classification Gotse Delchev lignite can be classified as metalignite with calorific value -15.86 MJ/kg and huminite reflectance -0.246%. The... more
The lignite seam was sampled in ten sections. According to the International In-Seam Coal Classification Gotse Delchev lignite can be classified as metalignite with calorific value -15.86 MJ/kg and huminite reflectance -0.246%. The petrographic composition is dominated by the huminite group macerals among which detrohuminite (mainly densinite) is prevailing. The contents of liptinite macerals are relatively high (19.5% avg.), mainly due to the presence of detritic liptinite particles. Resinite contents are low, thus suggesting precursor vegetation composed mainly of deciduous trees and herbaceous plants. The inertinite group is represented by funginite and inertodetrinite in very low amounts (0.31% avg.). The ash yield is high which argues for a rheotrophic environment in the ancient peat-mire. The maceral indices point to peat formation in a limnic to telmatic inundated marsh, characterized by frequent changes of the water level.
Twenty-four coal samples were collected from a gallery in the eastern part of the Maritza West basin in order to determine their inorganic composition. A variety of major, minor and accessory minerals is present. The mineral composition... more
Twenty-four coal samples were collected from a gallery in the eastern part of the Maritza West basin in order to determine their inorganic composition. A variety of major, minor and accessory minerals is present. The mineral composition is dominated mainly by pyrite, gypsum and calcite, and to a lesser extent limonite, quartz, kaolinite, montmorillonite, illite, chlorite and plagioclase. Jarosite, hematite, halloysite, mica, K-feldspar, aragonite, siderite and dolomite were also established in very low amounts. These were formed during the syngenetic and epigenetic stages of mineral generation. The former one is characterized mainly by the formation of pyrite, carbonates, silicates and sulphates, whereas the Fe-oxyhydroxides, partially carbonates and almost all silicates are of detrital origin. During the epigenetic stage carbonates, sulphates, clay minerals, pyrite and Fe-oxyhydroxides were formed. Alteration products of other detrital and authigenic minerals like gypsum, jarosite, limonite, chlorite, kaolinite, illite, mica and calcite were generated too.
Two limestone beds from Staniantsi Basin, Western Bulgaria, were sampled in an attempt to provide additional data on the palaeoenvironmental conditions during the deposition of the lacustrine sequence in that basin. Microscopy, XRD, SEM... more
Two limestone beds from Staniantsi Basin, Western Bulgaria, were sampled in an attempt to provide additional data on the palaeoenvironmental conditions during the deposition of the lacustrine sequence in that basin. Microscopy, XRD, SEM and sieving analysis, together with field observations, were applied in order to study the rock's structural and textural settings. The data indicate that sedimentation processed in a relatively shallow marginal type of basin and was significantly affected by the climatic conditions. The limestones were formed during the cooler and drier climatic phases in shallow lacustrine to palustrine environment due to predominantly biogenic and biogenically-induced carbonate sedimentation. Along the southern basin margin, rich charophyte vegetation developed, which acted as a filter to the detrital sediment input. The composition of the studied limestones generally reflects the composition of the surrounding rocks, thus indicating that most of the detrital and dissolved sedimentary material originated from the weathering of these rocks.
Резюме. Въглищни пластове от (Пернишки, Бобовдолски и Пирински басейн) са опробвани с по 10 до 12 пластови проби. Въглищните аншлиф-брикети са изследвани в отразена бяла и флуоресцентна светлина в маслена имерсия и е измерена... more
Резюме. Въглищни пластове от (Пернишки, Бобовдолски и Пирински басейн) са опробвани с по 10 до 12 пластови проби. Въглищните аншлиф-брикети са изследвани в отразена бяла и флуоресцентна светлина в маслена имерсия и е измерена отражателната способност на хуминита. Изчислени са индексите на торфения фациес, според които е определен типа на торфените блата в трите басейна. Според резултатите от химичния състав на въглищната пепел е определена киселинността на средата и типа на подхранване на древните торфени блата. Като цяло за въглищата от Пернишката провинция най-високо е съдържанието на гелифицирани мацерали при минимално присъствие на фюзенизирани. Блатата, в които се е осъществявало торфонатрупването са лимнично-телматични предимно реотрофни и обводнени. Подхранването е смесено-грунтово и повърхностно с привнос на теригенен материал. Между северната (Пернишки и Бобовдолски басейни) и южната част (Пирински басейн) на провинцията съществуват и различия. В северната част блатата са по-слабо обводнени с понижаващо се водно ниво и с елементи на мезотрофни блата, подхранването с теригенен материал преобладава над грунтовото, киселинността на средата е малко по-висока, отколкото в южната. Въглищата от северната част са по-богати на липоидни и фюзенизирани мацерали, на минерално вещество и в тях количеството на мацералите от подгрупа Телохуминит е по-голямо. Въглищата от южната част са по-богати на алгинит, на гелифицирани мацерали като цяло и особено на тези от подгрупа Детрохуминит. В южната част на провинцията участието на иглолистна растителност в торфонатрупването е по-слабо. Отражението на хуминита е най-високо в Пиринския басейн.