Geochemistry Of Coals Research Articles

Organic petrology and geochemistry of Triassic and Jurassic coals of the Tabas Basin, Northeastern/Central Iran

Jurassic and Triassic coals and organic matter-rich shales of the Tabas Basin, Iran, were investigated with respect to their thermal maturation and petrographic composition. The Triassic coals of the Parvadeh coal field range in vitrinite reflectance between 1.17% and 1.37% and the Jurassic coals of the Mazino coal field between 2.08% and 2.29% VRr. Maceral analysis revealed a predominance of vitrinite in all samples, with slightly higher percentages of inertinite in the Jurassic samples. Rock–Eval analyses confirm the presence of type III kerogen in the Triassic coals, while the Jurassic coals contain strongly carbonized residual kerogen. The range of sulfur contents for coals from the Parvadeh coal field (0.37% to 4.64%) and Mazino coal field (0.45% to 2.92%) is related to the effect of marine water in peat. The studied samples are characterized by the predominance of short- over long-chained n-alkanes. The relatively high Pr/Ph ratios indicate predominance of terrestrial organic matter whereas Pr/n-C17 and Ph/n-C18 ratios prove oxic conditions during deposition. In addition, the DBT/Phen ratio shows that these coals formed in fluvial/deltaic environments. Molecular geochemical parameters such as carbon preference index (CPI, 0.99–1.04), methyl phenanthrene index (MPI, 1.20–1.60), methyl naphthalene ratio (MNR, 1.61–3.45), and ethyl naphthalene ratio (ENR, 4–6.78) confirm the high maturity of the samples. Burial and thermal history reconstruction indicates necessity of an erosional thickness of about 4000 m in the Parvadeh area. Towards the Mazino area, a higher basal heat flow up to 80 mW m−2 is assumed for the Paleogene leading to higher maturities.

Mineralogy and geochemistry of feed coals and combustion residues of the Kangal power plant (Sivas, Turkey)

This study focuses on mineralogical and geochemical compositions of feed coal (FC) and combustion residues, namely fly ash (FA) and bottom ash (BA) samples, obtained from the Kangal coal-fired power plant in central Turkey. The X-ray powder diffraction data indicate that carbonate and clay minerals are dominant phases in the FC samples. In the FA samples, quartz, hematite, anhydrite, lime, and feldspar are generally dominant and abundant phases, whereas calcite, ettringite, and portlandite are generally more abundant in the BA samples. The elements Mo, Cs, and U are significantly enriched in the studied FC, FA, and BA samples. The statistical analysis and SEM-EDX data show that Ca, Ti, and the vast majority of trace elements are inorganically affiliated, and only Tl and U have prob-able organic affinity in the FC. In addition, the redox conditions in the paleomires presumably resulting in Mo and U enrichment in FC, whereas their enrichment in FA and BA is most likely related to retention by CaO and Ca-sulfate. The Cs enrichment in FA is due to retention by glass. The elements in the FA and BA are distinguished into four groups according to their volatility during combustion. The elements As, Mo, Cd, Tl, and U (Group I) are the most volatile elements during combustion and condensation in the FA. The elements Li, Zn, Ga, Rb, Nb, Cs, Ba, La, and Pb (Group IV) did not become more volatile or less volatile during combustion and are located in BA. Nevertheless, Zn and Pb in the BA seem to be related to the presence of unaffected pyrite and sphalerite, and are due to low combustion efficiency of the boiler during the sampling period. Overall, enriched elements and minerals in FA and BA suggest that their disposal should be undertaken with caution.

New data on geology and germanium mineralization in the Hunchun Basin, northeastern China

The geochemistry and mineralogy of Palaeogene coals from the Hunchun Coalfield, Jilin Province, northeastern China, have been studied using X-ray fluorescence spectrometry, inductively coupled plasma mass spectrometry, scanning electron microscopy in combination with energy-dispersive X-ray spectrometry, and X-ray diffraction analysis of the low-temperature ash. The 22A Coal from the Banshi Mine is of subbituminous A to high volatile bituminous rank (0.53–0.56% Ro, ran) and has a low sulfur content (0.74% on average). The 22A Coal consists mainly of kaolinite, quartz, illite, and, to a lesser extent, plagioclase, siderite, and pyrite. As compared with the average world low-rank coals, the 22A Coal is enriched in As, Sb, Ge, Cs, and W.Combined with the geochemical features of six other coal seams from the Hunchun Coalfield, the terrigenous materials of the Hunchun coals were dominantly from Mesozoic (mostly Lower Cretaceous) volcanic rocks and Paleozoic granites and associated metamorphic rocks surrounding the coal basin. A minor source was the Paleogene volcaniclastics including some adakitic rocks, which are characterized by higher Sr/Y and La/Yb ratios. The Ge enrichments that are detected in some individual coal benches from the Hunchun Coalfield were related to tectonic uplift of the crystalline rocks surrounding the basin and their following denudation. The oxidized meteoric waters episodically influenced by volcanic-related hot springs might extract Ge from the source rocks and then precipitate it as a result of bio-chemical reduction, forming the mineralization disseminated in the coals.

Earliest Cretaceous Transgression of North America Recorded in Thick Coals: McMurray Sub-Basin, Canada

Strata of the Lower Cretaceous McMurray Formation in the McMurray Sub-Basin (MSB) of Alberta and Saskatchewan, Canada, comprise marginal marine, tidal-fluvial, fluvial and interfluve deposits. In the Firebag Tributary located in the northeastern portion of the sub-basin, a thick coal seam (up to >20 m) forms a semi-continuous bed at the top of the lowermost McMurray Fm deposits (herein referred to as Lower McMurray). In coastal plain settings, peat-forming mires are highly sensitive archives of base-level. We investigate the stratigraphic significance of coals in the Firebag Tributary by analyzing coal petrography (4 cores), coal geochemistry (2 cores), and coal distribution in ~4500 wells. Additionally, we record the first absolute age for the McMurray Fm through the dating of an ash layer within the coal seam.The petrographic character and distribution of coals in the northeastern part of the MSB suggest a complex history of base-level rise at the end of Lower McMurray deposition. Wetting-upward character coal seams record initial transgression of the Boreal Sea during a 4th order sea level rise (Milankovitch-scale) within lowstand to early transgressive systems tract conditions. Sea-level rise during Lower McMurray times was estimated based on temperate climate peat formation rates, as well as peat-to-coal compaction factors, and probably occurred on a scale of 0.5–3 mm a−1. Seam-internal wetting-upward cycles suggest that base-level rise was punctuated. Locally, compound and drying-upward character coals represent zones of high accommodation, wherein peat accumulation in mires was influenced by phases of syn-depositional subsidence and karst collapse. The thickest coals in the study area form an arc on a coastal plain as the Boreal Sea inundated east- to southeastward into the Firebag Tributary. Within the arc of thick coals, a north-south decrease in coal thickness is interpreted to reflect the general southward inundation of the Boreal Sea across the MSB. Exceptionally thick coals (>10 m) likely formed where basement processes (e.g., karsting in Devonian carbonates) provided preferential groundwater pathways.Chemical abrasion thermal ionization mass spectrometry dating of 5 sharply faceted zircons recovered from an ash bed within the coal provides the first absolute age (121.39 ± 0.2 Ma – Aptian) to the southward transgression of the Boreal Sea. We hypothesize that initial inundation of the MSB was related to tectonic activity in the Canadian Cordillera and the onset of magmatic flow in the western Coast Plutonic Complex.

Mineralogy and Geochemistry of Feed Coals and Combustion Residues from Tunbilek and Seyitmer Coal-Fired Power Plants in Western Turkey

This study focuses on the enrichment of elements in feed coal (FC) and combustion residues, namely, fly ash (FA) and bottom ash (BA) samples, picked up from the Tuncbilek and Seyitomer coal-fired power plants in western Turkey. The FCs in both plants have generally similar mineralogical compositions, although siderite and dolomite are more prominent in Tuncbilek and feldspar and pyrite are more abundant in Seyitomer. Minerals in the FA from both power plants are mainly quartz, hematite, magnetite, anhydrite, and mullite. Along with quartz, the Fe-oxides are dominant phases in the BA samples. Accessory minerals in the FCs, FAs, and BAs, such as chromite and pentlandite, were identified by combined scanning electron microscopy-energy dispersive X-ray analysis. Significant enrichments of Cr and Ni were detected in FCs, FAs, and BAs from both power plants. These enrichments are probably associated with pyrite, chromite, and pentlandite. Mercury was also significantly enriched in the Seyitomer FA, owing to Hg retention by chars and anhydrite. The Hg and Cl concentrations of char samples from FAs of both power plants indicate that Hg and especially Cl concentrations are much higher than those in the FCs.

Органическая геохимия углей Печорского угольного бассейна и гиперугли как перспективный продукт углехимии

Органическая геохимия углей Печорского угольного бассейна и гиперугли как перспективный продукт углехимии

Geochemistry of coal–bearing Permo−Triassic strata in Allan Hills, South Victoria Land, Antarctica: Implications for palaeoclimate

Major, trace and rare earth element (REE) geochemistry has been carried out in this paper to characterize source–rock weathering and climatic variability of the late Permian Weller Formation and the late Triassic Lashly Formation of Gondwana sequences which have yielded rich record of plant mega–and micro fossils associated with coal beds in post–glacial conditions in Allan Hills of South Victoria Land, Antarctica. The geochemistry suggests dominantly a felsic provenance with a volcanogenic input and role of weathering and hydrothermal alteration. The palaeoclimatic interpretation derived from geochemical analysis indicates warm, temperate and humid conditions during the late Permian, and warm and humid conditions during the late Triassic.

Characteristic of low rank coal from Warukin Formation, South Kalimantan and their implication for coal liquefaction

The research was conducted on petrology and geochemistry of coal at Warukin Formation, Barito Basin, in South Kalimantan. Research is focused on composition and behavior of low rank coal toward its liquefaction. The sampling location is in the coal mining of PT. Adaro Indonesia which involves some mining location such as Wara, Tutupan and Paringin area. The sampling was conducted in seam Wara 110, Wara 120, Wara 200, Tutupan 210 and Paringin 712 with ply by ply method. Sample analysis consists of proximate and ultimate properties, composition of maseral, reflectance vitrinite, as well as composition of mineral, major element and organic geochemistry. Experiment of coal liquefaction was conducted on the autoclave with temperature and pressure of 120° C and 14.17 psi. The problems are focusing on influence of maceral, mineralogy and geochemistry low rank coal of Warukin formation in Barito Basin on coal liquefaction, behavior of coal liquefaction to the change in variable of time to result of coal liquefaction yield. The physical and chemical characteristics of coal in Wara seam content are ash (< 7 %) adb, inherent moisture (< 31%) adb, volatile matter (< 5)%) adb and fixed carbon (< 33%) adb. Then in Tutupan and Paringin are ash < 3% adb, inherent moisture < 21% adb, volatile matter < 48% adb and fixed carbon < 40 % adb. Composition element in Wara coal are carbon < 64 % adb, hydrogen < 7 % adb, oxygen < 34% adb and nitrogen < 1% adb, then in Tutupan and Paringin seam consist of carbon (< 65 % adb), hydrogen (< 6 % adb), oxygen (< 32% adb) and nitrogen < 2% adb. The content of maseral in Wara seam coal consist of vitrinite, liptinite, inertinite maseral group which are 81%, 51% and 27% respectively. Result of coal liquefaction on Wara seam with time reaction of 30 minutes is 48.60 % and for 60 minutes is 51.27%. The result of liquefaction is decreasing on reaction time of 90 minutes and 120 minutes, which are 46.72%, 35.51% respectively. The liquefaction conversion obtained from Tutupan and Paringin seam within reaction time 30 minutes and 60 minutes are 8.22% and 15.46% respectively. The conversion is decreasing on reaction time 90 minutes and 120 minutes which of 6.23% and 5.54% respectively. The coal with more lignite is easier to be liquefied than sub-bituminous because the coal has higher hydroxyl group.

Geochemistry of Palaeogene coals from the Fuqiang Mine, Hunchun Coalfield, northeastern China: Composition, provenance, and relation to the adjacent polymetallic deposits

This paper describes the geochemistry of the two Palaeogene coal seams (FQ-23 and FQ-26) from the Fuqiang mine, Hunchun Coalfield, Jilin Province, northeastern China. The samples investigated consist of coal, parting, and roof and floor strata. The two Fuqiang coals are lignite/subbituminous rank and have low sulfur contents (0.13% and 0.16% on average, respectively). In comparison with the average values for common global low-rank coals, the Fuqiang coals are richer in W, Cs, Sb, Pb, Li, V, Ga, and Zr.The terrigenous components in the Fuqiang coals were derived from the Mesozoic (mostly Lower Cretaceous) and Paleozoic igneous and metamorphic rocks, which are abundant in areas surrounding the Hunchun coal basin. The elevated concentrations of trace elements are attributed to two processes: (1) Contribution of clastic materials derived from mineralized Paleozoic rocks, which also host economical ore deposits of these elements; and (2) Mobilisation and redeposition of these elements by acidic waters, which circulated within the coal basin. The latter is evidenced by enrichment in medium rare earth elements, distinct positive Gd anomalies, and high concentrations of boron in the coals. The overall similarity of the geochemical signatures of the Fuqiang coals and the adjacent Au, Cu and W deposits hosted by the Paleozoic igneous and metamorphic rocks underlying and bordering the Hunchun Basin, indicate that they are genetically linked.

Geochemistry of a middle Devonian cannel coal (Munindalen) in comparison with Carboniferous coals from Svalbard

Since the appearance of trees in the Devonian, coal preservation in the geological rock record considerably increased and since then terrestrial coals are an extraordinary large sink for carbon in the geosphere. In Munindalen near Pyramiden (Dickson Land, Svalbard), low mature middle to upper Devonian strata (Mimerdalen Subgroup) crop out, which bear well recognizable terrestrial coal seams. Here, we report new geochemical and petrographical data of this ancient coal and compare them with younger coals of Svalbard from the Carboniferous, a period when land-dwelling plants started to rule the terrestrial realm. Similar to other Devonian cannel coals (highly bituminous terrestrial coals), the Munindalen coals are rich in spores and were most likely formed by early lycopsid trees in a near-equatorial setting. Geochemical data are in line with a predominantly liptinite-related origin of the coaly matter and the coals demonstrate a high hydrocarbon (oil) generation potential [hydrogen index: 570 mg hydrocarbons (HC)/g total organic carbon (TOC)]. Biomarkers support a terrestrial plant origin of the coals and demonstrate the geochemical simplicity of these very early terrestrial plants (e.g., by the lack of specific diterpanes known from modern plants and the occurrence of sterane-related simple pregnanes).

Petrologic and organic geochemical characteristics of Late Permian bark coal in Mingshan coalmine, Southern China

Bark coal is found only in Late Permian age coals, and only at some specific locations in Southern China. The depositional environment of bark coal is not yet well understood. As a contribution to improving the understanding of the origin of this unusual coal component, the petrological characteristics and organic geochemistry of bark coal were investigated by gas chromatography (GC) analysis, gas chromatography-mass spectrometry (GC-MS) analysis, and coal petrology techniques. The samples were selected from the B3 coal seam in the Mingshan coal mine, Leping area, in the south of China. The thermal maturity and organic matter type of the samples were determined by Rock-Eval analysis and from organic geochemical data. Barkinite occurs were commonly in the middle and upper parts, and less commonly in the lower parts, of the B3 coal seam. Barkinite is type II kerogen, while other samples are type II-III kerogen, consistent with good hydrocarbon-generation potential. The thermal maturity of the samples is consistent with their being of early-mature to peak oil window maturity. Gas chromatograms obtained from the samples are dominated by long chain n-alkanes (n-C22 to n-C27) and high Carbon Preference Index (CPI) values, indicating terrestrial organic matter input. The biomarker parameters obtained from mass spectrometer data on m/z 191 and m/z 217 indicate that the formation of these samples was influenced by marine environment and the deposited organic matter was preserved under relatively oxic conditions.

Petrology, mineralogy and geochemistry of the Lower Cretaceous oil-prone coal and host rocks from the Laoheishan Basin, northeast China

The coal and host rocks (mainly oil shale partings) in the Laoheishan basin (NE China) are oil-prone. This study uses petrological, mineralogical and geochemical analyses to determine the reasons of high oil yield in the coal, and the origin and modes of occurrence of the minerals and elements in the coal and oil shale partings. The obtained data show that this sub-bituminous B coal has higher oil yield (av. 10%) than oil shale partings (av. 5.7%), consistent with a higher hydrogen content in the coal. This oil-prone coal has potential for comprehensive utilization due to the relatively high gross calorific value (av. 17.23 MJ/kg) in the semi-coke. The maceral composition suggests that the relatively high hydrogen content in the coal is mainly caused by higher resinite content. Palynological analysis of coal and oil shale partings mainly proved the presence of gymnosperms and ferns, revealing that the paleovegetation is dominated by lygodiacean-/osmundacean ground ferns and cupressaceaen/taxodiaceaen canopy trees, these canopy trees would have provided abundant hydrogen rich components (e.g. resin) to the paleomire. All the identified sporopollen suggests a warm-humid subtropical paleoclimate.Minerals in the coal include kaolinite, quartz, illite (and/or illite/smectite), chlorite, feldspar, calcite, and traces of pyrite, rutile and zircon, similar to the oil shale partings. Most of the minerals (quartz, feldspar, clay minerals, rutile and zircon) occur in layers within detrovitrinite and probably are of detrital origin. Pyrite and calcite are of epigenetic origin and probably derived from hydrothermal fluids. Compared with average Chinese coal, the Laoheishan coal is enriched in Zr, Nb, In and Sb. Zirconium and Nb mainly occur in zircon. Indium is both organically and inorganically associated, whereas antimony largely occurs in pyrite. REY (rare earth elements and yttrium) distribution patterns of coals and oil shale partings are dominated by Heavy-REY enrichment, whereas roof and floor samples are Medium-REY enriched. The M-HREY enrichment is probably caused by low-temperature hydrothermal fluids. The sedimentary input is the major controlling factor of geochemical patterns in coal and host rocks. The source rocks are probably felsic-intermediate igneous rocks from the surrounding basement, as indicated by relatively high Al2O3/TiO2 ratios (7–38), cross-plot between Zr/Ti and Nb/Y, negative Eu anomalies (0.28–0.96), the presence of K-feldspar and plagioclase, and lithic fragment types (such as granite and andesite) in the samples. In addition, source rocks of sediments have caused high Zr and Nb concentrations in the coal.

Peat-accumulation models affected by the transgression-regression: a case study of mineralogy and geochemistry of the Permo-Carboniferous coals in the Lingshi Deposit, Qinshui Basin, China

Mineralogy and geochemistry of Nos.1, 9 and 10 coals in the Lingshi Deposit, Qinshui Basin, China, are investigated in this paper, using industrial analysis, total sulfur and forms of sulfur analyses, optical microscope, scanning electron microscope equipped with energy dispersive X-ray spectrometer, X-ray powder diffraction, X-ray fluorescence, and inductively coupled plasma-mass spectrometers. The results show that the minerals in coals are mainly kaolinite, nacrite, dickite, palygorskite, calcite, pyrite, anatase, dolomite, siderite and barite. Kaolinite of terrigenous origin is commonly discovered in No. 1 coal, which results in a high concentration of SiO2 (up to 6.81%) and Al2O3 (up to 8.42%); In the process of coalification, kaolinite could be converted into dickite and nacrite in Nos. 9 and 10 coal; Pyrite, the host of W, Tl, and As, and palygorskite in Nos. 9 and 10 coals are formed under the influence of the transgression. Besides, Nos. 9 and 10 coals, affected by transgression, are similar in the element contents and distribution patterns with positive δYN anomalies (up to 1.44). However, No. 1 coal, normalized by No. 10 coal, is characterized by high concentration coefficients of Co, Ni, Sb, Li, Be, Sc, V, Cu, Ga, Rb, Cs, Ba, Pb and Th (2 < CC < 10), and these elements are derived from clay minerals of terrigenous origin, which means that Permo-Carboniferous coals in the Lingshi Deposit show the evolution of a regressive process in general.

Rethinking enrichments of trace element in low-rank coals: Preliminarily quantifying the effectiveness of local structure to stabilize humates

Trace element enrichment in coals has increasingly been focused in the community of coal geochemistry. To research the enrichment mechanism of trace element in coals on molecular/atomic scale is an important complement of field investigations, but relevant works are scattered. In the present work, the effect of local structure on the ability of main oxygen-containing groups to chelate trace element metal ions including –COO− and C6H5O− is preliminarily quantified. It is completed by evaluating the Mulliken charge excess ξ, i.e. the sum of Mulliken charge for metal ions and atoms involved in chelating functional groups. When electron-donating groups like benzene and its derivatives immediately connect to cation carboxylates, excess electron will be transferred to cation carboxylates, pulling down the ξ values and stabilizing metal–humate complexes. Otherwise, electron-withdrawing groups like C = C, C≡C, and C = O play a contrary role. Based on calculations, at the vicinity of ξ ≈ 0, the binding energy is highest. For monovalent cation ions, the most stable metal–humate complex is that chelated by small alkyl carboxylate, while the highest binding energy is not found for high-valent cation ions in the investigation. Meanwhile, both the combination of hydroxyl and carboxyl and hydroxyls have higher binding energies than the combination of hydroxyl and carbonyl or carboxyls at the same ξ range.

Geochemistry and Nanomineralogy of Feed Coals and Their Coal Combustion Residues from Two Different Coal-Based Industries in Northeast India

The mineralogy, as well as the geochemistry of feed coals, are very important parameters for understanding the process conditions in a thermal plant. The present paper describes the nanomineralogical and geochemical aspects of a few feed coals and associated coal fly ashes collected from tea processing and brick-making industries from Northeast India. The optical microscopy, X-ray diffraction, field emission scanning electron microscopy-energy dispersive spectroscopy (FESEM-EDS), and chemical analysis techniques were applied to determine this mineralogical and geochemical aspect. Inductively coupled-mass spectroscopy was used to explore the occurrence and distribution of trace and rare earth elements (REEs), which are economically important, and are reported in this paper. The major minerals such as kaolinite, pyrite, quartz, and calcite were found to be present in the feed coals with variations with respect to the type of feed samples. The FESEM-EDS analysis revealed the occurrence of nanosphere consisit...

Trace element geochemistry and mineralogy of coal from Samaleswari open cast coal block (S-OCB), Eastern India

Coal samples of Samaleswari open cast coal block (S-OCB) are high ash (Aad, mean value 35.43%) and low sulphur content (St, on dry basis, mean value 0.91% < 1%) in quality. The stratigraphic variation of volatile matter and fixed carbon (dry ash-free) reflect a progress of coal metamorphism with depth that accordance to the coal rank variation from lignite to high volatile bituminous in the studied borehole. The younger coal seams have greater detrital minerals (quartz, illite, rutile) influence whereas older coal seams have greater authigenic mineral (kaolinite, dolomite, siderite, apatite) contribution that are possibly due to subsidence and sediment transportation. In S-OCB coal trace elements affinities in-between mineral and organic fraction are identified with statistical hierarchical cluster analysis. The work is further supported by the use of chemical fractionation experiment that reveals the multi mode of occurrence of several environmentally concern and interested trace elements (Sb, As, Be, Cd, Cr, Co, Cu, Pb, Mn, Ni, Zn). Among the analysed trace elements Co, Mn and Zn have major silicate association along with significant carbonate/oxide/monosulfide association. Whereas As, Cd, Cu, Pb and Ni have dominant pyritic association with notable silicate and carbonate/oxide/monosulfide association. The rest three elements (Sb, Be, Cr) have principally organic association with minor silicate and carbonate/oxide/monosulfide association. The stratigraphic variation of organo-mineral matrix content and detrital-authigenic mineral ratio are primarily related to coal rank. Geochemical character of coal also reflects a light towards proper utilisation of S-OCB coal from technical and environmental view point.

The impact of rapid heating by intrusion on the geochemistry and petrography of coals and organic-rich shales in the Illinois Basin

Igneous intrusion into organic-rich sedimentary rocks and coals has been suggested as a factor in the large-scale release of 13C–depleted thermogenic CH4, which may have led to global warming and mass extinction events in the geologic past. If a significant release of 13C–depleted thermogenic CH4 results from the intrusion of coal or organic-rich rocks, then it should produce 13C–enriched residual coal and dispersed organics in rocks adjacent to the intrusion due to the release of isotopically lighter CH4 gas. A review of the literature suggests only minor changes in the δ13Corg of coals adjacent to intrusions; however, a few studies have shown that changes in δ13Corg in intruded shales may be slightly more pronounced. The current study further evaluates the geochemical, isotopic, and petrographic changes that result from contact metamorphism and specifically compares the intrusion of coal to that of an organic-rich shale collected from the same general vicinity. Data for two different transects of intruded Pennsylvanian coal (Danville (No. 7) Coal) and an intruded organic-rich shale in the southern part of the Illinois Basin are presented.Both transects show similar increases in mean vitrinite reflectance (Rr); reflectance increases from background levels of 0.66% to 4.40% in the Danville (No. 7) Coal and 0.71% to 4.78% in the organic-rich shale. In addition, both transects show the formation of isotropic coke, and even development of fine circular mosaic anisotropic coke structure at and near the contact with the intrusion, along with the visual loss of liptinites at higher reflectances. In the Danville Coal transect, volatile matter, N, H, S, and O decrease whereas fixed carbon, C, and ash increase approaching the intrusion. The coal shows a marked decrease in remaining hydrocarbon potential (S2) and hydrogen index (HI) and an increase in Tmax (°C). Trends in most of the Rock-Eval parameters for the organic-rich shale are less clear due to variations in the amount of organic matter present, but a significant increase in thermal maturity (Tmax, 0C) is observed.No systematic changes in δ13C occur in the No. 7 Coal transect as the intrusion is approached, with δ13C varying between −25.4‰ and −24.8‰. The organic-rich shale transect shows a minor 1.2‰ enrichment in δ13C (from −25.2‰ to −24.0‰) within 2m of the intrusion. These isotopic shifts are not of a magnitude that would be expected if associated with a large-scale release of thermogenic CH4. In addition, no evidence exists in either transect for 13C–depleted condensed gas or pyrolytic carbon at the intrusion contact that could have moderated the isotopic signature. These data agree with those reported previously that indicate no clear isotopic evidence for large-scale CH4 generation due to rapid heating by igneous intrusion into coals or sedimentary rocks.

Coal emissions adverse human health effects associated with ultrafine/nano-particles role and resultant engineering controls

There are multiple elements which enable coal geochemistry: (1) boiler and pollution control system design parameters, (2) temperature of flue gas at collection point, (3) feed coal and also other fuels like petroleum coke, tires and biomass geochemistry and (4) fuel feed particle size distribution homogeneity distribution, maintenance of pulverisers, etc. Even though there is a large number of hazardous element pollutants in the coal-processing industry, investigations on micrometer and nanometer-sized particles including their aqueous colloids formation reactions and their behaviour entering the environment are relatively few in numbers. X-ray diffraction (XRD), High Resolution-Transmission Electron microscopy (HR-TEM)/ (Energy Dispersive Spectroscopy) EDS/ (selected-area diffraction pattern) SAED, Field Emission-Scanning Electron Microscopy (FE-SEM)/EDS and granulometric distribution analysis were used as an integrated characterization techniques tool box to determine both geochemistry and nanomineralogy for coal fly ashes (CFAs) from Brazil´s largest coal power plant. Ultrafine/nano-particles size distribution from coal combustion emissions was estimated during the tests. In addition the iron and silicon content was determined as 54.6% of the total 390 different particles observed by electron bean, results aimed that these two particles represent major minerals in the environment particles normally. These data may help in future investigations to asses human health actions related with nano-particles.

Organic geochemistry and palynology of coals and coal-bearing mangrove sediments of the Neogene Sandakan Formation, Northeast Sabah, Malaysia

The coals and coal-bearing mangrove sediments of Sandakan Formation have been evaluated for their source rock potential, paleoredox conditions and source of organic input, as well as the age and paleovegetation distribution using geochemical and petrographical methods. The studied samples were generally rich in organic carbon, which varied from 0.60 (massive mudstone) to 62.37wt% (coal). The studied samples have vitrinite reflectance (Ro) ranging from 0.31 to 0.49% and Tmax values ranging from 353 to 436°C indicating an immature to very early mature stage for hydrocarbon generation. The sediments were dominated by Type III kerogen, with some Type II/III kerogen, suggesting a significant land plant contribution to the organic matter. The bimodal distribution displayed by gas chromatogram, with a clear odd/even carbon number and skewed to higher molecular weight carbon (nC31), indicating a transitional depositional environment. The variation in pristane/phytane ratio, varied from 0.71 to 2.97, suggesting an alternating anoxic and oxic deposition conditions. The presence of marine dinoflagellate cyst in the mangrove and offshore mudstones were consistent with the relatively higher sulphur content in the studied samples which indicate marine inundations.Palynomorph recovered in this study, with abundant mangrove and freshwater types of pollen, suggesting a biogeographical distribution of ancient mangrove vegetation that expanded landward into the freshwater peat swamp setting and hinterland. The presence of marker species, viz. Florschuetzia levipoli, F. meridionalis and F. semilobata delineated an Early Miocene to Middle Miocene age for the Sandakan sediments.

Improving spatial predictability of petroleum resources within the Central Tertiary Basin, Spitsbergen: A geochemical and petrographic study of coals from the eastern and western coalfields

Central Tertiary Basin (CTB) coals from a variety of palaeogeographic conditions within the Longyear and Verkhnij seams, were sampled to assess the relationship between the petroleum present, the remaining generation potential and coal geochemistry in order to improve the spatial predictability of petroleum resources within the basin. Vitrinite reflectance (VR) values from the CTB coals have been shown to be suppressed (Marshall et al., 2015b). This study attempts to quantify and correct for this suppression effect by applying the Lo (1993) method (LoVR), which uses Hydrogen Index (HI) values to modify VR data, and the coal Rank(Sr) scale of Suggate (2000, 2002), a technique not affected by suppression. In addition, the oil generation and expulsion thresholds for the CTB coals were investigated, with discussions on oil potential versus marine influence upon the mires in which the coals formed.A pseudo-van Krevelen diagram shows that the majority of the coals plot on the Type II kerogen line, while the remainder plot between the Types II and III kerogen lines, with HI between 151 and 410mgHC/g TOC; however, maceral analysis shows that Type III kerogen predominates. This is attributed to the presence of abundant fluorescing (oil-prone) vitrinites. The LoVR, Tmax and Rank(Sr) parameters all show that maturity increases from basin margins towards basin centre (i.e. from Bassen to Lunckefjellet, to Breinosa and Colesdalen) and indicate that all the coals are within the oil generation window. The marginal samples at Bassen are within the early mature stage of the oil window (i.e. ~0.7% RO); meaning the threshold for oil generation in the basin could not be clearly defined. However, the observed maturation trend somewhat parallels the maturation pathway of the New Zealand Coal Band (NZ Coal Band) and the “envelope” of the Sykes and Snowdon (2002) NZ coal data-set; therefore, it is considered that the oil generation threshold for the CTB coals is likely at Rank(Sr) ~9–10, Tmax~420–430°C in line with the observed rise in Bitumen Index (BI). Some of the Lunckefjellet coals and all the Breinosa and Colesdalen coals have either reached or progressed beyond the threshold for oil expulsion as indicated by the peak in HI at Rank(Sr) ~11–12, LoVR ~0.75–0.85% RO, Tmax~430–440°C. The peak in BI at Rank(Sr) ~12.5–13.5 suggests that some of the Lunckefjellet and Breinosa coals, and all the Colesdalen coals have reached the “effective oil window”.Total sulphur (ST) contents range between 0.46 and 12.05% indicating non-marine to strong marine influence upon precursor peats, with ST contents of the Longyear seam appearing to record instances of coastal retreat associated with base level rise. Marine deposition seems to significantly control the distribution of oil-prone coals within seams and across the CTB. The levels of marine influence (as indicated by ST content) show clear positive relationships between BI and HI within the Bassen samples because they have not started expelling oil. Conversely, the levels of marine influence show clear negative relationships with BI and HI within the Colesdalen samples because they have commenced oil expulsion, and probably reached the “effective oil window”. The more marine influenced coals appear to have commenced petroleum generation relatively earlier, which is a plausible explanation why the coals from the Lunckefjellet locality appear to be at different stages within the oil window.