accelerator mass spectrometer ages for the younger dryas event in atlantic canada abstract in atlantic canada bulk sediment dates for the onset of a late glacial cooling widely regarded as the younger dryas event are highly variable ranging from 14 300 270 to 10 800 100 yr b p we present the first accelerator mass spectrometer ams 14c dates from atlantic canada at or close to the boundaries of this event from six sites in new brunswick and nova scotia the mean of five dates places the onset of this cooling at ca 10 770 yr b p the inclusion of a sixth perhaps anomalously old date changes the mean to 10 880 yr b p the termination averages three dates ca 10 000 yr b p these dates place the timing of the younger dryas event in atlantic canada closer in line with the traditional chronozone boundaries of 11 000 and 10 000 yr b p in northwest europe

element mobility from fresh and long stored acidic fly ashes associated with an australian power station abstract the mobility of major and trace elements in a series of ashes from pulverised coal combustion stored in dams and similar repositories for up to 25 years has been investigated comparison with the mobility of the same elements from equivalent fresh dry ash material has been used to provide a basis for assessing the long term changes in element mobility during ash storage laboratory testing at different initial ph values indicates an increase in the natural acidic ph and a decrease in the buffering capacity of the ash by contact with water during handling and storage suggesting loss of components such as so 4 from the surfaces of the ash particles with even relatively brief water contact most elements show lesser degrees of mobility from ashes that have been stored under water even if only for a relatively short period than from the fresh dry material there are however some exceptions such as mo which appear to have increased mobility from the longer stored ashes due to a progressive rise in ph levels relatively little difference is noted between the mobility of most elements in the water stored ashes regardless of whether they were only recently emplaced or have been in the dam for 20 years or more this suggests that equilibrium has been established between the ash and the pore water and that once the readily leached fraction had been removed the ash water system remained relatively stable with time ash that had been deposited under water in a trial ash pond and then drained and exposed to dry storage conditions for many years however showed many similar leaching characteristics to the fresh dry ash material this suggests that at least some elements or ions e g so 4 2 may be re adsorbed on to the ash particles with exposure after drying or that additional elements of similar characteristics may be released allowing a new set of equilibrium conditions to be established the concentrations of most elements in the laboratory test leachates are of a similar order of magnitude to the concentrations of the same elements in the water in the present day ash pond this increases confidence in the use of laboratory tests to provide guidance on the expected behaviour of ash when exposed to water in actual field situations

terrestrial fossils in the marine presumpscot formation implications for late wisconsinan paleoenvironments and isostatic rebound along the coast of maine investigation of terrestrially derived organic remains within the late glacial marine presumpscot formation near portland maine adds one new shrub species six moss species and representatives of six families of insects to the fossil biota of the deposit white spruce picea glauca dominates the plant macrofossil assemblage the dominant pollen type is also spruce the total biotic assemblage probably represents remnants of a forest floor litter layer eroded along a stream and subsequently deposited offshore three accelerator mass spectrometer ams dates on spruce needles and cones suggest rapid burial with marine regression from the area by ca 11 500 bp

plant and insect fossils at norwood in south central minnesota a record of late glacial succession abstract the norwood site in sibley co minnesota contains 1 6 m of silt resting on till and overlain by peat the base of the peat has been radiocarbon dated at 12 400 60 and the top at 11 200 250 yr b p the pollen plant macrofossils and insect remains in the basal silt consist of boreal species inhabiting open environments but not tundra no modern analogue exists for the insect assemblage which includes elements of boreal forest tundra forest and western affinities the transition from an unstable open environment to a stable coniferous forest is reflected by both plant and insect fossils and is interpreted as a successional rather than a climatic event during this time of significant biologic change the climate is inferred to have been relatively uniform with temperatures similar to those presently existing in the boreal forest south of the tundra forest transition zone the geologic and ecologic succession at norwood is generally similar to that presently associated with ice stagnation of the klutlan glacier in the yukon territory localized successional sequences similar to those at norwood are conceived to have occurred repeatedly during the melting of the laurentide ice and thus the proposed model has potentially broad application to the interpretation of late glacial sequences

seismo acoustic wavefield of strombolian explosions at yasur volcano vanuatu using a broadband seismo acoustic network infrasound arrays and infrasonic sensors on tethered balloons seismo acoustic wavefields at volcanoes contain rich information on shallow magma transport and subaerial eruption processes and inform our understanding of how volcanoes work acoustic wavefields from eruptions are predicted to be directional but sampling this wavefield directivity is challenging because infrasound sensors are usually deployed on the ground surface we attempt to overcome this observational limitation using a novel deployment of infrasound sensors on tethered balloons in tandem with a suite of dense ground based seismo acoustic geochemical and eruption imaging instrumentation we conducted a collaborative multiparametric field experiment at the active yasur volcano tanna island vanuatu from 26 july to 2 august 2016 our observations include data from a temporary network of 11 broadband seismometers 6 single infrasonic microphones 7 small aperture 3 element infrasound arrays 2 infrasound sensor packages on tethered balloons an ftir a flir 2 scanning flyspecs and various visual imaging data scoria and ash samples were collected for petrological analyses this unprecedented dataset should provide a unique window into processes operating in the shallow magma plumbing system and their relation to subaerial eruption dynamics seismo acoustic wavefields at volcanoes contain rich information on shallow magma transport and subaerial eruption processes and inform our understanding of how volcanoes work acoustic wavefields from eruptions are predicted to be directional but sampling this wavefield directivity is challenging because infrasound sensors are usually deployed on the ground surface we attempt to overcome this observational limitation using a novel deployment of infrasound sensors on tethered balloons in tandem with a suite of dense ground based seismo acoustic geochemical and eruption imaging instrumentation we conducted a collaborative multiparametric field experiment at the active yasur volcano tanna island vanuatu from 26 july to 2 august 2016 our observations include data from a temporary network of 11 broadband seismometers 6 single infrasonic microphones 7 small aperture 3 element infrasound arrays 2 infrasound sensor packages on tethered balloons an ftir a flir 2 scanning flyspecs and various visua

factors controlling geochemical and mineralogical compositions of coals preserved within marine carbonate successions a case study from the heshan coalfield southern china abstract the late permian coals in the heshan coalfield of southern china are preserved within marine carbonate successions and characterized by super high organic sulfur 5 13 10 82 minerals identified in the coals include quartz kaolinite illite mixed layer illite smectite albite pyrite marcasite calcite and dolomite along with trace amounts of smectite fluorite strontianite rey bearing carbonate minerals jarosite and water bearing fe oxysulfate the coals are very rich in trace elements including f up to 3362 g g v up to 270 g g se up to 24 4 g g mo up to 142 g g u up to 111 g g and to a lesser extent sr y zr nb cd cs heavy rare earth elements hf ta w hg and th previous studies attributed the high organic sulfur and elevated trace elements to the seawater influence or the formation of soil horizons before the accumulation of peat in the basin however mineralogical and geochemical data presented in this study have shown that the sediment source region and multi stage hydrothermal fluids are the dominant influences on the mineralogical composition and elevated trace elements in the coal although seawater influence also contributed to the composition of the mineral matter for example a large proportion of the quartz and clay minerals as well as almost all the albite in both the coal benches and the parting mudstones were derived from detrital materials of terrigenous origin in the yunkai upland high concentrations of lithophile trace elements were also derived from the sediment source region minerals including fluorite calcite dolomite strontianite and rey bearing carbonate minerals were derived from multi stage hydrothermal activities high concentrations of v mo and u that occur through the coal seam sections were probably derived from hydrothermal solutions during peat accumulation or at the early diagenetic stages the hydrothermal fluids also corroded the syngenetically formed minerals quartz albite and pyrite and caused re distribution of lithophile elements from partings to the underlying coal benches resulting in higher key element ratios yb la nb ta and zr hf and more abundant heavy rare earth elements in the coal benches than in the immediately overlying partings

co2 ecbm field tests in the ishikari coal basin of japan abstract the feasibility of extracting gas from coal seam while storing carbon dioxide underground was evaluated in japan a co2 ecbm project had begun near the town of yubari on the island of hokkaido in northern japan the primary coal seam of interest was a 5 6 m thick yubari coal seam located at the depth of 900 m a micro pilot test with a single well and multi well co2 injection tests involving an injection and production wells were carried out in the period between may 2004 and october 2007 there were a variety of tests conducted in the injection well including an initial water injection fall off test and a series of co2 injection and fall off tests although gas production rate was obviously enhanced by co2 injection water production rate was not clearly affected by co2 injection several injection tests suggested that injectivity of co2 into the virgin coal seam saturated with water was eventually increased as the water saturation near the injector was decreased by the injected co2 it was estimated that low injectivity of co2 was caused by the reduction in permeability induced by coal swelling n2 flooding test was performed in 2006 to evaluate the effectiveness of n2 injection on improving well injectivity the n2 flooding test showed that daily co2 injection rate was boosted but only temporarily moreover the permeability did not return to the initial value after co2 and n2 were repeatedly injected it was also indicated that the coal matrix swelling might create a high stress zone near to the injection well

occurrence of minerals within fractures and matrix of selected bowen and ruhr basin coals abstract late permian age samples of black coal from the coeval bandanna formation and baralaba coal measures of queensland s bowen basin as well as carboniferous coal from germany s ruhr basin were investigated this paper presents scanning electron microscope sem analysis of the mode of occurrence of minerals within these coals and characterisation of the natural fractures present within the samples the coal samples located proximal to orogenic fronts in both basins are structurally complex with multiple generations of mineralisation evident stable isotope analyses of carbonates from selected samples indicate that methanogenesis related co2 reduction has occurred at two of the bowen basin sampling locations ankerite precipitated from a magmatic fluid or basinal brine is associated with significant sulphide mineralisation within brecciated ruhr coal proximal to major fault intersections with anticlines and has been meteorically altered to ferroan calcite and sulphates in coal from immediately below the carboniferous cretaceous unconformity similar alteration has occurred within a bowen basin coal sample close to the present day land surface variation of mineralisation within both the cleats and the coal matrix occurs on a fine scale with crystals of multiple mineral species often being present within micrometres of each other

response of interior north america to abrupt climate oscillations in the north atlantic region during the last deglaciation several broad scale climatic oscillations during the last deglaciation are well documented in regions around the north atlantic ocean this paper reviews empirical evidence for these deglacial climatic oscillations from non coastal north america and discusses implications for testing climatic simulations and for understanding the cause and transmittal mechanisms paleoclimatic interpretation of oxygen isotope records from several small sites in the eastern great lakes region indicates a classic deglacial climatic sequence that is comparable with records from europe and greenland the climatic events as interpreted from crawford lake oxygen isotopes include the bolling allerod boa warming at 12 700 14c bp a warm boa at 12 500 10 920 14c bp an intra allerod cold period shortly before 11 000 14c bp a cold younger dryas yd climate reversal at 10 920 10 000 14c bp the holocene warming at 10 000 14c bp a brief preboreal oscillation pb at 9650 14c bp and an early holocene cold event at 7500 14c bp 8200 cal bp some of these events were also evident from changes in upland and aquatic vegetation and sediment lithology the pronounced yd climatic reversal has been documented from pollen records along the ecotones at this time and from glacier readvances in the great lakes region along the rocky mountains from alberta to colorado the yd event is indicated by alpine glacier advance and or shift in timberline vegetation in minnesota and upper new york early holocene climatic instability is also suggested by oxygen isotope records and or varve thickness the regional variations in evidence for the yd and other events in north america suggest that climatic oscillations may have different expressions in paleo records depending on geographic location and characteristics of a particular site the extent and magnitude of these climatic oscillations across north america suggest that these oscillations are an expression of climatic change that was probably widespread rather than locally induced by a nearby glacier the location of these sites implies that climatic signals were likely carried over the northern hemisphere through the atmosphere as indicated by general circulation models we hypothesize that the lack of evidence for a cold yd in interior north america west of the great lakes region and east of the rocky mountains was caused by the trapping of cold arctic air mass north of the laurentide ice sheet and by uninterrupted northward expansion of warm caribbean air this strongly contrasted climate also produced non analogous biological assemblages

impact of sulphur and trace element geochemistry on the utilization of a marine influenced coal case study from the south wales variscan foreland basin abstract incremental channel samples through two high volatile a bituminous coal seams the amman rider and bute seams below and above the vanderbeckei marine band at the westphalian a b boundary have been analysed using proximate petrographic inductively coupled plasma mass spectrometry icp ms x ray fluorescence xrf and scanning electron microscopy with energy dispersive x ray sem edx techniques the results show that both coals are vitrinite rich and indicate a similar history of palaeomire development with a period of falling water tables towards the middle plies of each seam mean sulphur contents in the coal with the marine roof the amman rider seam 4 19 wt are almost 4 times higher than in the coal with a non marine roof the bute seam 1 09 wt implying that high sulphur contents are derived from sea water sulphate in both coals sulphur is predominantly in the form of pyritic sulphur both syngenetic framboidal and euhedral crystals and epigenetic vein and cleat fill pyrite are present relatively constant levels of organic sulphur at around 2 have been recorded in the amman rider seam sulphur levels in the basal and top plies of each seam are at least twice that of the ply with the lowest sulphur content in the seam reflecting the stages in palaeomire development most strongly influenced by sulphate containing waters thorium uranium ratios are below 2 9 in the coal with a marine roof the amman rider seam indicating an enrichment of u from sea water most marked at the top and bottom of the seam the seam without a marine roof shows th u ratios between 2 5 and 4 9 indicating mild marine enrichment of u the concentrations of environmentally significant trace elements eses are correlated with either the ash or sulphur contents or both the correlation between s and pb as cu ni in the coal with a marine roof implies an origin of these eses from sea water and their mode of occurrence in sulphide minerals most eses in this coal are present at levels at least twice that of the global average in coals the exceptions being pb and zn which have concentrations less than half the global average by contrast the coal without a marine roof and with lower sulphur contents has most eses present at concentrations less than a third of the global average the exceptions being ni and cu diagenetic hydrothermal activity is documented in the middle ply of the coal with a marine roof this hydrothermal system redistributed the sulphur pb and as in this ply the principal utilization of bituminous coals in the south wales coalfield is as feed coals in power station boilers the resultant concentration of most eses in the solid residues from power plant coal combustion theoretically can be alleviated by careful blending of feed coals with low and high ese contents

climatic and limnological changes associated with the younger dryas in atlantic canada pollen diatom and chironomid fossils from the sediments of a core from brier island bog lake nova scotia were studied in an attempt to relate changes in microfossil composition to a climatic cooling in atlantic canada correlative with the european younger dryas ca 10 to 11 ka our paleolimnological data were then compared to similar types of data from splan pond new brunswick to determine if there were any significant differences between a coastal and a more inland site nonarboreal pollen was dominant throughout the brier island core and the interval 10 0 11 0 ka did not show the typical decline in picea and increases in tundra like vegetation characteristic of many sites in atlantic canada however the limnological indicators did undergo marked changes in taxon composition the chironomid assemblage was initially dominated by shallow water warm adapted chironomid taxa followed by abundant sergentia a cold stenotherm during 10 11 ka sergentia disappeared in the post younger dryas interval and the warm adapted genera resumed dominance chironomid inferred paleotemperature reconstructions revealed that at both brier island bog lake and splan pond summer surface water temperatures dropped abruptly to between 13 and 17 c during the 10 11 ka interval suggesting that a cooler climate was present in atlantic canada correlative with the european younger dryas diatom assemblage changes during the same period corroborate the occurrence of limnological fluctuations

climatic changes in areas adjacent to the north atlantic during the last glacial interglacial transition 14 9 ka bp a contribution to igcp 253 this paper presents a summary of the evidence for climatic changes during the last glacial interglacial transition 14 9 ka bp in land areas adjacent to the north atlantic it is a synthesis of the results of the 12 regional summaries compiled by contributors to the north atlantic seaboard programme of igcp 253 that are published separately in this issue of journal of quaternary science eighteen palaeotemperature curves are compared and arranged in three transects one from southern europe to spitsbergen a second from ireland to poland and the third from southern new england to the labrador baffin shelf area ten maps are presented that summarise the synoptic climatic conditions of the region in 500 year time periods the purpose of the exercise is to examine the extent to which any emerging patterns support the ruddiman and mclntyre model of large scale shifts in the position of the oceanic polar front during the last glacial interglacial transition some broad agreement emerges although the influence of oceanic changes is diminished in areas that lay in close proximity to the laurentide and fennoscandian ice sheets attention is drawn to limitations in the compilations and to the potential for improved models in the future

a rapid climatic change at the end of the younger dryas in south sweden palaeoclimatic and palaeoenvironmental reconstructions based on fossil insect assemblages a rapid climatic change at the end of the younger dryas in s sweden palaeoclimatic and palaeo environmental reconstructions based on fossil insect assemblages

mineral occurrence and its impact on fracture generation in selected qinshui basin coals an experimental perspective abstract the effect of mineral matter on the fracture evolution was investigated for lower permian and upper pennsylvanian coal samples from the qinshui basin of china optical microscopy scanning electron microscopy with energy dispersive x ray spectrometry sem eds and x ray computed tomography x ray ct were used to investigate the composition and modes of occurrence of minerals within the coals and to characterize the natural and induced fractures present within the samples the spatial distribution of mineral matter investigated by x ray ct demonstrates that the variation of mineralization within the cleats fractures occurred at fine scales and most of minerals were scattered in coal core samples the original fractures normally were present as two sets one set was almost parallel to the bedding plane and the other was almost perpendicular to the bedding plane for created fractures the difference in density between the matrix and mineral matter may weaken the cohesion of coals and it could explain why the created fractures propagate along the junction of minerals and organic coal matrix the internal fracture porosities varied from 0 06 to 20 69 which indicates a strong internal heterogeneity of the coals after a stress is applied the inclination of the main shear fractures ranges from 55 to 95 using energy analysis the fracture energy appears to represent nearly half of the total dissipated energy which can be correlated with the fracture density and orientation the formation and distribution of shear fractures is related to the spatial distribution of mineral matter and the overall mineral content these investigations serve to characterize hydro fracturing and pulverized coal generation during coalbed methane development

leaching of elements from bottom ash economizer fly ash and fly ash from two coal fired power plants abstract to assess how elements leach from several types of coal combustion products ccps and to better understand possible risks from ccp use or disposal coal ashes were sampled from two bituminous coal fired power plants one plant located in ohio burns high sulfur about 3 9 upper pennsylvanian pittsburgh coal from the monongahela group of the central appalachian basin the other in new mexico burns low sulfur about 0 76 upper cretaceous fruitland formation coal from the san juan basin colorado plateau the sampled ccps from the ohio plant were bottom ash ba economizer fly ash efa and fly ash fa the sampled ccps from the new mexico plant were ba mixed fa efa fa and cyclone separated coarse and fine fractions of a fa efa and fa blend subsamples of each ash were leached using the long term leaching 60 day duration component of the synthetic groundwater leaching procedure sglp or the toxicity characteristic leaching procedure tclp 18 hour duration these ashes were all alkaline leachate concentrations and leachabilities of the elements from the ccps were similar between corresponding ccp types ba efa and fa from each plant the leachabilities of most elements were lowest in ba least leachable and increased from efa to fa most leachable ca and sr were leached more from efa than from either ba or fa leachability of most elements also increased as fa particle size decreased possibly due in part to increasing specific surface areas several oxyanion forming elements as mo se u and v leached more under sglp than under tclp the opposite was true for most other elements analyzed

column leaching of coal and its combustion residues shizuishan china column leaching experiments were performed on the samples of feed coal fly ash and bottom ashes from the shizuishan coal fired power plant china in order to investigate the leaching behaviour and potential environmental impact of the 11 potentially hazardous elements as cd co cr hg mo ni pb se th and u the results show that most of the elements are more easily leachable from the feed coal in comparison with the combustion residues and basically show a similar leaching behavior from the fly and bottom ashes the modes of occurrence of elements time and ph play an important role in controlling the leaching behavior of the elements from the solid samples there is a certain relationship between the leached concentrations of most of the elements and their contents in the fly and bottom ashes the maximum leached concentrations of ni co as cd mo and u from the coal or its combustion residues by leaching action of acid rain exceed their limited concentrations recommended in relevant environment quality standard

fluorine content and distribution pattern in chinese coals abstract about 300 coal samples were collected to study the fluorine content and distribution pattern in chinese coals in different coal basins and geologic periods the permo carboniferous and jurassic coals in the north china plate and northwest china account for nearly 90 of chinese coals and their fluorine content is 20 300 mg kg mostly about 50 100 mg kg fluorine content of permo carboniferous coals the main steam coals in china is 50 300 mg kg jurassic coals 20 70 mg kg there are great differences in fluorine content of late permian coals in southwest china 50 3000 mg kg which accounts for only 7 of chinese coals according to the proportions of the coals with different fluorine content in chinese coal resources the average fluorine content of chinese coals is about 82 mg kg which is close to the world average 80 mg kg most chinese coals are low fluorine coals fluorine content in chinese coals is closely related with structure position of coal basins the degree of volcanic activity and magma intrusion as well as the age and source of the volcanic and magmatic rock frequent volcanic activity and magma intrusion is the main reason for fluorine rich coals and stone coals in south qinling mountain daba area and southwest china where fluorine content is about 50 3000 mg kg fluorine content in all platform areas where magma activity is less is comparatively low about 20 200 mg kg

allerod younger dryas coleoptera from western cape breton island nova scotia canada studies of coleoptera remains from two late glacial sites on cape breton island nova scotia canada present a picture of the paleoenvironment and paleoclimate during the allerod younger dryas transition in the maritimes region they provide evidence for the younger dryas event in northeastern north america between 11 300 and 10 800 bp the beetle assemblages at the campbell site are typical of faunas of the modern middle to northern boreal forest the west mabou site contains beetle fossils younger than 10 900 bp possibly as young as 10 500 bp extending into the time period of the younger dryas dated from 10 800 to 10 000 bp in the maritimes a cold climate indicator recognizable in the beetle fauna olophrum boreale occurs in relative abundance and provides an interesting comparison with sites in europe where the same northern boreo montane species is evident at the beginning of the younger dryas

analysis origin and significance of mineral matter in coal an updated review abstract the material classed as mineral matter in coal embraces crystalline mineral materials as well as a range of inorganic elements that occur in non crystalline form this review outlines the methods that may be used to evaluate the percentage of mineral matter for a coal sample as opposed to the ash yield and to identify the minerals their individual percentages and their modes of occurrence within the coal the principal techniques include low temperature oxygen plasma ashing quantitative evaluation of x ray diffraction data observation using optical microscopy and a combination of observation chemical analysis and in some cases mapping based on scanning electron microscopy and related methods a range of other techniques may also be used to provide additional information on particular mineral matter components processes responsible for mineral matter formation include detrital input biogenic activity and authigenic precipitation at different stages of the coal s depositional and post depositional history differential migration of non mineral inorganic elements may also occur in lower rank coals and expulsion of non mineral inorganics may take place with rank advance knowledge of the mineral matter may be of assistance in understanding the modes of trace element occurrence with implications for assessing possible environmental impacts and also the potential for recovery of economic products from coal the behaviour of different mineral matter components at high temperatures is also discussed as well as methods for mineralogical analysis of ashes and other coal utilization products information from mineral matter studies may provide an improved basis for understanding coal formation and for evaluating the response of particular coals to different combustion gasification and coking processes

atmospheric iron deposition in the northwestern pacific ocean and its adjacent marginal seas the importance of coal burning this study applied a regional air quality model incorporated with an emission module to quantitatively differentiate the atmospheric iron sources originating from lithogenic dusts or coal burning fly ashes deposited in the northwestern pacific ocean and its marginal seas particular attention was paid to the high iron content of fly ashes emitted from steel and iron plants burning coals using the year 2007 as an example the modeling results exhibit large seasonal variations in iron deposition with highest deposition fluxes occurred during spring and autumn which are comparable to the seasonal fluctuation of chlorophyll a concentrations estimated by satellite images in the oceanic regions fly ash from coal burning accounted for 7 2 of the total iron deposited over the northwestern pacific ocean and 15 of that over the northern south china sea after considering the difference of iron solubility in the aerosols anthropogenic aerosol associated with coal burning would be the major bioavailable iron source in the surface water of the oceanic regions

experimental mineral dissolution in berea sandstone reacted with co2 or so2 co2 in nacl brine under co2 sequestration conditions a comparison of the geochemical changes induced in sandstone by either pure or impure co2 at geological co2 storage conditions was investigated samples of berea sandstone were batch reacted in 1 w v nacl brine saturated with pure co2 or mixed so2 co2 gas for 360 h at 50 degrees c and 10 mpa geochemical analysis of incremental water samples showed increases in the concentrations of elements such as calcium magnesium iron manganese and silicon throughout experiments likely being the products of carbonate and reactive silicate dissolution scanning electron microscope images taken of specific points of interest before and after batch reactions confirmed dissolution of carbonates but showed no reaction for minerals such as k feldspar the magnitude of apparent mineral reaction was higher for the mixed gas so2 co2 brine experiment with geochemical modelling also indicating greater dissolution of reactive silicates such as chlorite and potential precipitation of amorphous silica c 2014 elsevier b v all rights reserved

late glacial allerod younger dryas buried organic deposits nova scotia canada a contribution to the north atlantic seaboard programme of igcp 253 termination of the pleistocene abstract numerous deposits of organic shallow pond sediments and wetland peat accumulations buried by minerogenic sediments have been discovered throughout nova scotia they are interpreted as representing a late glacial climatic oscillation correlative with the allerod younger dryas event of europe and the north atlantic ocean the organic deposits began forming during the warm or warming interval following deglaciation and often record a transition to colder conditions the climatic reversion recorded in many deposits began about 10 8 ka bp and continued or sustained cooling culminated in the burial of the organic deposits by minerogenic sediments indicative of solifluction and mass wasting processes some deposits provide strong evidence for regeneration or rejuvenation of local glaciers as the organic deposits are not as susceptible as lake sediments to contamination by old carbon they provide a more reliable chronological framework for deglaciation and late glacial vegetational history palynological evidence shows that pioneer herb tundra communities colonized some areas shortly after 13 ka bp willow and birch shrubs followed soon after spruce woodlands had migrated into the region prior to 10 8 ka bp but had not yet reached the northeast mainland and cape breton island cooling after 10 8 ka bp decimated tree populations and favoured a return to shrub and herb communities the record in the buried deposits was then truncated by deposition of minerogenic sediments and lake sediment sequences from deeper basins with continuous sedimentation are required to complete the record

partitioning of mineralogical and inorganic geochemical components of coals from santa catarina brazil by industrial beneficiation processes abstract comparative studies of the mineral matter and trace elements in 12 pairs of run of mine rom and clean coal products from beneficiation plants in santa catarina southern brazil have been carried out using low temperature oxygen plasma ashing x ray diffraction and chemical analysis techniques with the aim of evaluating the effect of coal preparation on the mineralogy and chemical composition of the final coal products the results show that substantial reductions in mineral matter and ash percentages are associated with beneficiation of coals mined from the different deposits these reductions are accompanied by changes in the percentages of fe2o3 in the respective coal ashes due to the reduction in the proportion of pyrite in the mineral matter and also by a reduction in the percentage of na2o possibly due to ion exchange within the clay minerals the relative proportions of quartz clay minerals and minor phases such as calcite and feldspar mainly albite within the mineral matter are not however significantly changed by the beneficiation processes the concentrations of most trace elements in the beneficiation products are similar to the respective concentrations in the relevant rom materials or are reduced to an extent similar to that of the total mineral matter percentage for the respective coal samples this suggests an association mainly with the clay rich mineral matter the concentrations of as and pb however are reduced to a greater extent for most samples by the beneficiation processes consistent with a pyrite association concentrations of ge u and zr are higher in many of the clean coals than in the respective run of mine materials suggesting the possibility of preferential association at least for some deposits with the organic rich fractions of the coals concerned

wisconsinan late glacial environmental change in nova scotia a regional synthesis a synthesis of the interpreted vegetational and climatic history of nova scotia during the wisconsinan late glacial period 14 9 ka bp is presented and described in 500 year intervals the concomitant regional deglaciation history of the region is also described a synthesis chart is provided which includes a qualitative curve of temperature reconstructions for the late glacial period

spatiotemporal variations in eruption style and magnitude at yasur volcano vanuatu part 2 extending strombolian eruption classifications in this companion study to simons et al bull volcanol 82 2020a we examine strombolian style explosive activity at yasur vanuatu over 11 weeks via seismic thermal infrared and visual observations in part 1 of this study simons et al bull volcanol 82 2020a we investigated the link between variations in the surface expression and style of volcanism at yasur in relation to vent shallow conduit and shallow magma reservoir processes now in part 2 based on the database of 4998 explosions we describe define and classify yasur s strombolian eruption styles and magnitudes and compare and contrast to stromboli and other similar centres the styles of most of yasur s explosions fit with other known strombolian eruptions but they are 2 3 times more frequent and with higher average eruption heights than at stromboli observed activity at yasur also produced more ash than at stromboli the most powerful eruptive periods are dominated by type 2a explosions ballistics and ash and type 2b ash dominated explosions a new type of strombolian style explosion was observed at yasur and is here termed a type 3 explosion they occur when vents are buried by a thick cap of loose poorly sorted pyroclastic breccia type 3 explosions begin as a series of emergent ash rich jets that rupture and fountain from the breccia cover generating prolonged jetting of ash to form vigorous low plumes the loose breccia cover apparently dissipates the violent early phase of the explosion the greatest hazard of type comes from their occurrence with little warning from a smooth crater floor without an apparent vent and after longer than typical intervals between eruptions the findings extend the observed range of strombolian explosion styles and imply that surficial vent cover and burial may influence gas slug stability and contribute to variations in ash and ballistic output

leaching of trace elements from pittsburgh coal mill rejects compared with coal combustion products from a coal fired power plant in ohio usa abstract we investigated the leachability of elements from mill rejects from the high sulfur bituminous upper pennsylvanian pittsburgh coal using the synthetic groundwater leaching procedure sglp long term leaching ltl and the u s environmental protection agency s epa s toxicity characteristic leaching procedure tclp and compared their leaching behavior with that of three coal combustion products ccps bottom ash economizer fly ash and fly ash from the same coal none of the environmentally hazardous resource conservation and recovery act of 1976 rcra metals analyzed in the leachates from the mill rejects or the ccps exceeded u s epa toxicity characteristics as ba cd cr hg pb and se most trace elements leached the least from mill rejects and bottom ash and leached the most from fly ash the elements ca co mg mn and sr however were more concentrated in mill reject leachates than ccp leachates most trace elements increased in concentration with increasing sglp and ltl leaching duration but as and v decreased in concentration with time in mill reject leachates suggesting sorption or precipitation of these elements was occurring

aerial seismology using balloon based barometers seismology on venus has long eluded planetary scientists due to extreme temperature and pressure conditions on its surface which most electronics cannot withstand for mission durations required for ground based seismic studies we show that infrasonic low frequency pressure fluctuations generated as a result of ground motion produced by an artificial seismic source known as a seismic hammer and recorded using sensitive microbarometers deployed on a tethered balloon are able to replicate the frequency content of ground motion we also show that weak artificial seismic activity thus produced may be geolocated by using multiple airborne barometers the success of this technique paves the way for balloon based aero seismology leading to a potentially revolutionary method to perform seismic studies from a remote airborne station on the earth and solar system objects with substantial atmospheres such as venus and titan

changes in late quaternary vegetation and insect communities in southwestern ontario abstract the gage street site in kitchener ontario is a peat marl sequence representing continuous lacustrine sedimentation from the time of deglaciation ca 13 000 yr b p through 6900 yr b p insect pollen and plant macrofossil remains isolated from the sediments indicate that from ca 13 000 to 12 500 yr b p the region was characterized by parkland tundra vegetation existing within thermal conditions more analogous to those today of the midboreal forest the transition from parkland to coniferous forest at ca 12 500 yr b p occurred within a climate that was only gradually warming by the time of the spruce pine transition at 10 500 yr b p an insect fauna had become established that is typical of southwestern ontario today the replacement of this fauna at ca 8400 yr b p by one characteristic of the lowlands of the east central united states represents the beginning of hypsithermal conditions in southern ontario vegetation and insects indicate that the climate continued to gradually warm through the mid holocene

a comparative evaluation of minerals and trace elements in the ashes from lignite coal refuse and biomass fired power plants abstract coal being a limited source of energy extraction of energy from other sources like lignite coal refuse and biomass is being attempted worldwide the minerals and inorganic elements present in fuel feeds pose different technological and environmental concerns lignite ash refuse ash and biomass ash collected from indian power plants burning lignite coal refuse and mustard stalk respectively were analyzed for physico chemical characteristics and trace elements the lignite ash has high sio 2 cao mgo al 2 o 3 and so 3 the refuse ash has high sio 2 and fe 2 o 3 but low so 3 the biomass ash has high sio 2 but low al 2 o 3 and high cao mgo k 2 o na 2 o so 3 and p 2 o 5 a substantial presence of chloride 2 1 was observed in the biomass ash quartz is the most abundant mineral species other minerals are mullite hematite gehlenite anhydrite and calcite in the lignite ash orthoclase in the refuse ash albite sanidine gehlenite anhydrite and calcite in the biomass ash ashes with high concentrations 100 mg kg of trace elements are lignite ash v

mercury in western canadian subbituminous coal a weighted average study to evaluate potential mercury reduction by selective mining abstract western canadian subbituminous coal is mined using strip mining methods the coal is used to feed coal fired power plants for electricity generation parameters that influence the mercury content of these coals include the occurrence and frequency of partings in the seam weathering and epigenetic mineralization most partings have higher mercury content than the coal layers in the same seam with the single bentonite bed having the highest hg content however some high ash components such as sandy siltstone do not follow this trend the incorporation of the high mercury partings into the as mined coal may increase the hg content in the feed coal epigenetic mineralization may also increase the mercury content of coal depending on the nature of the mineralization calculation of the weighted mean of mercury content for various combination of lithological components of a seam illustrates how these components influence the total mercury content of the seam this approach also suggests how selective mining might be used to reduce mercury in as mined coal results of weighted average calculations of mercury indicate that the thin lithological units with moderate mercury may not necessarily influence that overall weighted average of hg for a seam however there can be exception such as presence of thin 3 5 cm bentonite parting with high mercury in a 94 5 cm seam that increased the mercury content of seam by 83 4

geochemistry of trace elements in chinese coals a review of abundances genetic types impacts on human health and industrial utilization abstract china will continue to be one of the largest coal producers and users in the world the high volume of coal use in china has focused attention on the amounts of toxic trace elements released from coal combustions and also the valuable trace elements extracted or potentially utilized from coal ash compared to world coals chinese coals have normal background values for most trace elements with the exception of higher li 31 8 g g zr 89 5 g g nb 9 44 g g ta 0 62 g g hf 3 71 g g th 5 84 g g and rare earth elements la lu y 136 g g this is not only due to the higher ash yields of chinese coals but also to alkali volcanic ashes found in some southwestern coals the background values of toxic elements of hg 0 163 g g as 3 79 g g and f 130 g g in chinese coals are comparable to coals from most other countries the genetic types for trace element enrichment of chinese coals include source rock controlled marine environment controlled hydrothermal fluid controlled including magmatic low temperature hydrothermal fluid and submarine exhalation controlled subtypes groundwater controlled and volcanic ash controlled the background values of trace elements were dominated by sediment source regions low temperature hydrothermal fluid was one of the major factors for the local enrichment of trace elements in southwestern china serious human health problems caused by indoor combustion of coal in china include endemic fluorosis arsenosis selenosis and lung cancer endemic fluorosis mainly occurring in western guizhou was mostly attributed to the high fluorine in clay that was used as a briquette binder for fine coals in addition to a small quantity of fluorine from coal fluorine in the coal from endemic fluorosis areas of western guizhou is within the usual range found in china and the world endemic arsenosis in southwestern guizhou is attributed to indoor combustion of high as coal endemic selenosis in enshi of hubei was due to high se in carbonaceous siliceous rocks and carbonaceous shales fine particles of quartz released into air during coal combustion are hypothesized as a possible cause for the lung cancer epidemic in xuanwei yunnan china valuable elements including ge ga u ree rare earth element nb zr and re are concentrated to levels comparable to conventional economic deposits in several coals or coal bearing strata in china the ge deposits at lincang yunnan province and wulantuga inner mongolia have been exploited and industrially utilized the enrichment of ge in the two deposits was caused by hydrothermal fluids associated with adjacent granitoids the ga al ore deposit in the jungar coalfield inner mongolia was derived from the neighboring weathered and oxidized bauxite of the benxi formation pennsylvanian the nb ta zr hf ree ga deposits in the late permian coal bearing strata of eastern yunnan and chongqing of southwestern china were attributed to ashes of the alkali volcanic eruptions

comparative leaching experiments for trace elements in raw coal laboratory ash fly ash and bottom ash abstract samples of raw coal fly ash and bottom ash have been collected from a chinese power plant together with laboratory ash obtained by ashing of the coal under 850 c comparative leaching experiments were carried out on each fraction under various ph conditions a mathematical model for leaching of trace elements has been developed and leaching intensity il has been calculated for each element the results show that ph of the solution leaching time and particularly properties and occurrence of the elements have a strong influence on leaching behavior

mineral matter and potentially hazardous trace elements in coals from qianxi fault depression area in southwestern guizhou china mineralogy coal chemistry and 21 potentially hazardous trace elements phtes of 44 coal samples from the qianxi fault depression area qfda in southwestern guizhou province china have been systematically studied the major minerals in coals studied are quartz kaolinite illite pyrite calcite smectite marcasite and accessory minerals including rutile dolomite siderite gypsum chlorite melanterite apatite collophane and florencite the sio2 content shows a broad variation 0 8 30 7 a high sio2 content in late permian coals reflects their enrichment in quartz the al2o3 content varies from 0 8 to 13 4 fe2o3 from 0 2 to 14 6 cao from al k ti na mg ca fe s a comparison with world coal averages shows that the late permian coals in qfda are highly enriched in as hg f and u and are slightly enriched in mo se th v and zn the late triassic coals in qfda are highly enriched in as and hg and are slightly enriched in mo th and u the concentrations of as hg mo se tl and zn in the qfda coal are higher than other guizhou coal and liupanshui coal nearby the qfda is an area strongly affected by the low temperature hydrothermal activity during its geologic history yanshanian age about 189 ma the coals in qfda are enriched in volatile phtes including as hg se sb mo among others the regions where the coals are enriched in as hg and f have been mapped the regions of coals enriched in volatile phtes overlap with the regions of noble metal ore deposits these coals are located in the cores of anticline and anticlinorium which are connected with the profound faults through the normal faults coals are enriched in volatile phtes as a result of the low temperature hydrothermal activity associated with tectonic faulting

allerod younger dryas lake temperatures from midge fossils in atlantic canada remains of freshwater midges are abundant in lake sediments and their species distributions are closely related to the surface water temperature of lakes their distributions thus provide a powerful tool for paleoclimatology the distribution of species in a core from splan pond in atlantic canada indicates that there were abrupt transitions in late glacial temperatures between warm and cold states the transitions are correlative with the well known warm allerod and cold younger dryas events in europe these data thus confirm the inference from palynological data that these events affected regions on both sides of the atlantic

geochemistry of sulfur and elements in coals from the antaibao surface mine pingshuo shanxi province china abstract coal bearing strata in the antaibao surface mine pingshuo mining district shanxi china occur in the taiyuan formation upper carboniferous and shanxi formation lower permian the most productive coal seams in the mine are the nos 11 9 and 4 twenty five samples of coals partings and roof shales from the nos 11 10 9 5 taiyuan formation and 4 shanxi formation seams in the antaibao mine were analyzed for ash and total sulfur contents and forms of sulfur the no 11 seam is a medium to high sulfur coal 1 3 3 1 s a coal sample 14 1 ash from the no 10 seam contains 3 4 and high ash coal 37 4 ash from the same seam contains only 0 4 total sulfur the no 9 seam is a low to medium sulfur coal 0 6 1 3 s the highest sulfur content among the samples is 5 8 total sulfur from a coal sample of the no 5 seam the no 4 seam is low sulfur coal 0 29 0 54 s the remarkable variation in sulfur content among the coal seams in the taiyuan and shanxi formations could reflect different depositional environments from coastal to lower deltaic plain for the taiyuan and from upper deltaic plain to fluvial basin for the shanxi formation the sulfate sulfur comes mainly from the oxidation of pyrite sixteen samples were analyzed for 26 major minor and trace elements by x ray fluorescence spectrometry the sr content is significantly higher in coals from the no 4 seam in the shanxi formation than those from nos 11 to 5 seams chlorine sr ca and p are elements bound organically while si al ti fe k na mg cr v ni rb ba and nb are mainly associated with minerals

geochemistry of rare earth elements in a marine influenced coal and its organic solvent extracts from the antaibao mining district shanxi china twenty six samples including roof bottom and coal plies of a marine influenced coal bed were collected from the antaibao mining district shanxi china the rare earth elements rees were determined in solids and organic solvent extracts the distribution pattern showed three distinct patterns shale like lree rich and hree rich this is attributed to the variable microenvironment of peat forming swamp the degree of marine influences and different ree sources rees in the coal are mainly controlled by detrital minerals but also affected by seawater the chondrite normalized ree patterns of the organic solvent extracts are distinctly different from those of corresponding original coal samples which show a negative eu anomaly a depletion of middle rees and an enrichment of hrees the lrees in coal extracts are likely adsorbed by hydrogen containing functional groups and hrees are likely bonded to carbon atoms

late glacial allerod younger dryas coleoptera from central cape breton island nova scotia canada coleoptera from three late glacial sites on cape breton island nova scotia canada provide proxy climate data from 12 600 to 10400 bp samples older than about 11 800 bp contain tundra to tree line species between 11 800 and about 10 800 bp beetle assemblages become typical of the modern boreal forest beetles younger than 10 800 bp responded to climatic deterioration during the younger dryas although coleopteran evidence for the younger dryas is not as strong as that presented by palynological and stratigraphic studies the appearance of olophrum boreale and other species found today in the northern boreal forest and on tundra or coastal tundra corresponds with the decline of shrub birch and the rise in willow and alder pollen beetles responded just as likely to changes in vegetation and ground cover as to changes in temperature the extent to which coleoptera were affected may lie somewhere between a moderated continental response seen in the great lakes region in north america and more extreme changes recorded in europe this response is consistent with shifts in the north atlantic oceanic polar front in the ruddiman and mcintyre model resumc les colkoptkres trouvks dans trois sites glaciaires tardifs de l ile du cap breton ouvelle cosse canada

mineralogy and geochemistry of the coals from the karmozd and kiasar coal mines mazandaran province iran abstract the karmozd and kiasar mines are two major coal producing areas in the central alborz coal bearing field northern iran this study focused on the mineralogy and geochemistry with respect to the mode of occurrence of elements in feed coals and element partitioning during coal preparation the low sulfur content in the coal seams indicates a non marine origin i e deposition in lacustrine and swamp environments detrital minerals in the coal seams are quartz feldspar albite and orthoclase mica muscovite and biotite amphibole hornblende and kaolinite authigenic minerals include pyrite calcite and chlorite the contents of most elements are within the general worldwide ranges with the exceptions of mn co and cr in some coal seams correlation coefficients between elements and the ash yield identified four separate groups of elements the sequential extraction results indicate that al na k zn cu and co principally occur in the silicates whereas pb and cr mainly occur in the organic fraction calcium and mg display strong affinities to the carbonate phase while cd mainly occurs in the water soluble and organic fractions the calculated removability index shows that the coal cleaning method in zirab not only removes mineral matter and pyritic sulfur but also reduces the content of most inorganic elements

quantification of mineral matter in the argonne premium coals using interactive rietveld based x ray diffraction abstract the mineral matter in the eight reference north american coal samples of the argonne premium coal series has been investigated on a quantitative basis using x ray diffraction xrd techniques x ray diffraction data obtained from electronic low temperature oxygen plasma ash lta residues from ashes produced by heating the coals in air at 370 c and also from the raw coals themselves were evaluated using an interactive data processing system siroquant based on rietveld interpretation methods the results from the three types of material lta 370 c ash and raw coal were compared for each sample this allowed the components present in the raw coals in crystalline form to be recognised separately from mineral artifacts produced particularly in the low rank coals from interaction of organically associated elements ca s etc during the two ashing processes after the allowance for the production of any artifacts the quantitative mineral assemblages identified from xrd of the raw coals were found to be consistent even for coals having a relatively low ash percentage around 5 with the results obtained from the respective mineral concentrates prepared by the ashing methods the effects of heating the coal to 370 c could also be distinguished relative to the raw coal or the lta through changes in components such as pyrite and the clay minerals although some areas of uncertainty exist particularly with magnesium in the low rank coals the calculated chemical compositions of the coal ash derived from the mineral mixtures identified for each coal were also found to be consistent with the results of direct chemical analysis of the respective coal ash materials

from in situ coal to the final coal product a case study of the danville coal member indiana a surface coal mine operation and preparation plant in southwestern indiana was sampled to examine variations in coal quality and coal petrography parameters for the danville coal member of the dugger formation pennsylvanian desmoinesian westphalian d representative samples from in situ coal preparation plant feeds and a final coal product were collected in order to compare coal quality coal petrography trace element concentrations and ash chemistry of the coal to those of the product coal quality parameters of the in situ samples and various feeds coarse refuse and final product were variable the quality of the final coal product was best predicted by the coal quality of the clean coal feed from the middle portions of the seam some trace element contents especially lead and arsenic varied between the coal feeds and the product lead contents increased in the feeds and product compared to the channel sample of the raw coal possibly due to contamination in the handling process

partitioning of elements and macerals during preparation of antaibao coal abstract analyses of the macerals ash sulfur and 43 major and trace elements were performed on samples of feed coal cleaned coal middlings and slime collected from the antaibao coal preparation plant china and also on samples from coal preparation experiments this study is focused on the partitioning of elements and macerals during coal preparation and potential environment aspects of the elements the conclusions are as follows 1 in comparison with the feed coal the cleaned coal has a higher vitrinite content and relatively lower inertinite and exinite contents whereas the middlings and slime have lower vitrinite and exinite contents and relatively higher inertinite contents the vitrinite contents in the size segregated cleaned coals were observed to show a slightly increasing tendency with increasing particle size while the inertinite contents decreased 2 physical coal cleaning is not only effective for removal of ash and sulfur but also in reducing the concentration of most elements as cd co cs hg fe k mg nb and ni are observed to show a high degree of removal while br be cu u mn zn and organic sulfur are enriched in the cleaned coal and show a lower degree of removal the large sized cleaned coal is cleaner than the smaller sized fractions 3 the middlings especially the slime are enriched in s hg cr v zn etc so that these fractions should not be directly used as fuel in addition the concentration of pb and v in the process water exceeds the limit of relevant environmental water quality standard consequently it is necessary to develop new processes to remove ash sulfur and hazardous trace elements to the maximum extent further studies on deep processing of the middlings and slime and cleaning of the process water should also be performed

multiproxy evidence of an early holocene 8 2 kyr climate oscillation in central nova scotia canada an early holocene lake sediment record from central nova scotia contains a minerogenic oscillation that is closely correlative with the 8 2 kyr event ca 8200 cal yr bp an event that has not been reported elsewhere in atlantic canada a variety of biological and sedimentological indicators have been examined to characterise autochthonous and allochthonous changes that occurred during this time the minerogenic upper oscillation uo ca 8400 cal yr bp is marked by an increase in the chrysophyte diatom ratio following the oscillation the diatom community reflects a shift to more productive less acidic conditions the pollen record shows no major response to this short lived event lithostratigraphic analyses indicates that the uo is characterised by an increase in clastic content magnetic susceptibility and mean sediment grain size all indicators of changing environmental conditions most likely the result of regional cooling the taylor lake record adds to a growing body of evidence for a widespread hemispheric climate oscillation at 8 2 kyr copyright 2002 john wiley sons ltd

detection of artificially generated seismic signals using balloon borne infrasound sensors abstract we conducted an experiment in pahrump nevada in june 2017 where artificial seismic signals were created using a seismic hammer and the possibility of detecting them from their acoustic signature was examined in this work we analyze the pressure signals recorded by highly sensitive barometers deployed on the ground and on tethers suspended from balloons our signal processing results show that wind noise experienced by a barometer on a free flying balloon is lower compared to one on a moored balloon this has never been experimentally demonstrated in the lower troposphere while seismoacoustic signals were not recorded on the hot air balloon platform owing to operational challenges we demonstrate the detection of seismoacoustic signals on our moored balloon platform our results have important implications for performing seismology in harsh surface environments such as venus through atmospheric remote sensing

geochemical and mineralogical anomalies of the late permian coal in the zhijin coalfield of southwest china and their volcanic origin abstract this paper describes the influence of volcanic ash on the concentrations and occurrences of associated elements in coal in the zhijin coalfield in western guizhou province china our studies reveal that the no 9 coal seam in the zhijin coalfield has very high content of fe 4 34 cu 369 90 g g u 49 6 g g mo 63 10 g g zn 33 97 g g and zr 841 80 g g the studies have also found that elements such as fe and cu do not occur as sulfides in this coal seam in sharp contrast to many other coal seams in china the geochemical and mineralogical anomalies of the coal seam are attributed to synsedimentary volcanic ash in addition to normal macerals and minerals in coal a volcanic influenced material vim derived from volcanic ash detrital material of terrigenous origin and organic matter was identified under polarized light reflectance microscopy and scanning electron microscopy equipped with energy dispersive x ray edx analyzer the volcanic influenced material is the main carrier of the above elements in this coal six types of the volcanic influenced material vim 1 vim 2 vim 3 vim 4 vim 5 and vim 6 are further distinguished on the basis of their structures and compositions to the best of our knowledge this is the first report that presents a detailed classification of coal components with a high content of volcanic ash

distribution of environmental sensitive trace elements in the eocene sorgun coals turkey abstract the distribution of trace elements in the lower eocene coal seam mined in the yeniceltek kucukkohne and ayridam coal mines from the sorgun basin was investigated in relation to ash content and maceral composition the coal seam is mainly composed of huminite in the present study 35 samples from five seam sections were collected on the basis of megascopic characteristics results were determined using an energy dispersive polarised x ray fluorescence edp xrf spectrometer on a whole coal dry basis most of the major and trace elements studied are enriched in high ash samples while ba br mn and w show relative enrichments in low ash samples most of elements studied such as ga ce la th nb rb zr v cu u pb sb cs sn cr se y and zn are primarily associated with mineral matter clay minerals arsenic and a part of zn se and sb are probably concentrated in pyrites in the samples element concentrations show statistically significant negative correlations with many macerals and positive relationships with only attrinite that is mainly mixed with mineral matter clay minerals and small quartz grains in the samples nine trace elements as cr mn ni pb sb se th and u considered as potentially hazardous air pollutants are present in low to moderate concentrations the mean values of trace element concentrations display relative enrichments in se 2 8 ppm th 21 ppm and w 26 ppm in the investigated samples in comparison with other coals in the world

geochemistry and origin of elements in some uk coals abstract twenty four uk coals ranging in rank with 4 6 37 6 volatile matter were analysed for 46 major and trace elements the samples were obtained from the uk coal bank and are representative of the major uk coal fields the major element distributions are interpreted in terms of the mineralogical variations quartz and kaolinite are largely responsible for the si and al carbonates for ca and mg and pyrite for fe also exerting an influence in some samples are siderite al phosphate minerals and illite based on statistical relationships with the major elements rb cr th ce zr y ga la ta nb and v are thought to be mainly present in the clay minerals and as mo sb tl se and bi and pb are probably present in pyrite strontium and ba are concentrated in a restricted number of samples related to the phosphate minerals germanium is the only element for which a major organic association can be demonstrated elements with an indirect association with the organic matter are na cl and br in porefluids and possibly te the ash content is controlled mainly by the detrital input and the trace elements related to the ash content are therefore those elements associated with the clay minerals variations with rank would appear to be mainly related to the moisture content porefluids the trace elements associated with the quartz and clay minerals are thought to be dominantly detrital in origin the non detrital elements essentially those contained in pyrite are thought to have been incorporated in the depositional environment from waters with enhanced salinities through seawater ingress hence there are positive relationships between s and trace element concentrations

mobilisation of elements from coal due to batch reactor experiments with co2 and water at 40 c and 9 5mpa injection of co2 into coal seams with or without enhanced coal bed methane recovery co2 ecbm is one method for sequestering co2 greenhouse gas emissions in the subsurface conventional saline formations that could be used for co2 sequestration also may have coal seams within the seal rock units however relatively little is known concerning the potential interactions between co2 acidified water and coal this geochemical study investigates the short term mobilisation of elements from selected samples of coal exposed to highly reactive conditions expected in the mixing front between the injected co2 plume and groundwater coals were obtained from both the permian bowen basin of queensland australia and the carboniferous ruhr basin of germany within a custom built batch reactor cubes of coal were reacted with supercritical co2 saturated water at 9 5mpa and 40 degrees celsius for 72h carbonate minerals within the coal cleats and matrix were most affected by the co2 water experiments as indicated by both sem images and reaction water chemistry an experiment with n2 saturated water to compare water only mobilisation with co2 water mobilisation was also done for a single sample in each of the seven sets of coals the effluent concentrations of several elements including al ba ca fe mg and mn consistently were greater during the co2 water coal experiments in comparison to water only mobilisation from the same samples whereas elements such as ag b hg k li na and sb were much less likely to be preferentially mobilised by co2 acidified water

a preliminary study on the enrichment mechanism and occurrence of hazardous trace elements in the tertiary lignite from the shenbei coalfield china abstract the cr and ni contents are high in the eocene lignite of the shenbei coalfield which is a small intracontinental basin located in liaoning province china in this paper we studied the distribution origin and occurrence of cr ni and other hazardous trace elements in the shenbei lignite on the basis of coal petrology and geochemistry of the lignite and combustion products the following conclusions on the shenbei lignite can be drawn 1 the dominant maceral group in the shenbei coal is huminite humodetrinite accounting for 96 99 of the total maceral inertinite content is less than 1 liptinite content sporinite and cutinite is 0 2 1 6 common minerals in the shenbei lignite include clay minerals kaolinite pyrite and quartz and calcite and siderite chromite is not present in the lignite 2 potentially hazardous trace elements such as co 22 g g cr 79 g g cu 63 g g zn 93 g g v 88 g g and ni 75 g g are strongly enriched in the shenbei lignite compared with average concentration of trace elements in the chinese coal and worldwide lignite these elements are mainly associated with fulvic acid fa and or coal organic macromolecular compounds in most of the studied lignite samples indicating an organic association and enrichment of these elements in the shenbei lignite 3 unusually high trace elements contents in the shenbei lignite are derived mainly from the olivine basalt country rock of coal basin that consists of 52 7 plagioclase 17 8 pyroxene 14 olivine and 15 5 ti fe oxide minerals these olivine basalts have higher cr ni pb and zn contents than other types of rock and worldwide basalts do 4 fly ash of the shenbei lignite with 90 1 50 m amorphous particles and 8 1 10 m cenosphere has high contents of zn 23 707 g g be 12 g g sr 1574 g g pb 486 g g and cr 349 g g in particular the ferruginous micro cenoshperes contain 1 12 79 zn fine bottom ash

modes of occurrence of mercury and other trace elements in coals from the warrior field black warrior basin northwestern alabama abstract the mineralogic residence and abundance of trace metals is an important environmental issue data from the usgs coal quality database show that potentially toxic elements including hg as mo se cu and tl are enriched in a subset of coal samples in the black warrior basin of alabama usa although the coal as mined typically is low in these elements localized enrichments occur in high pyrite coals and near faults microscopic analyses demonstrate that the residence of these elements is dominantly in a late stage pyrite associated with structurally disrupted coal further our data suggest addition of hg to the coal matrix as well the source of these trace elements was hydrothermal fluids driven into the black warrior basin by alleghanian age tectonism

concentration and distribution of elements in late permian coals from western guizhou province china abstract with the aim of better understanding geochemistry of coal 71 late permian whole seam coal channel samples from western guizhou province southwest china were studied and 57 elements in them were determined the contents of al ca co cr cu fe ga hf k li mn mo nb ni sn ta ti th u v zr and rees in the late permian coals from western guizhou province are higher than the arithmetic means for the corresponding elements in the us coals whereas as ba br f hg p se and tl are lower compared to common chinese coals the contents of co cr cu ga hf li mn mo ni sc sn ti u v zn and zr in western guizhou coals are higher and as f hg rb sb tl and w are lower five groups of elements may be classified according to their mode of occurrence in coal the first two group a tm yb lu y er ho dy tb ce la nd pr gd sm and group b as sr k rb ba f ash si sn ga hf al ta zr be th na have high positive correlation coefficients with ash yield and they show mainly inorganic affinity some elements from group b such as ba be ga hf and th are also characterized by significant aluminosilicate affinity in addition arsenic also exhibits high sulfide affinity r s fe 0 5 the elements which have negative or lower positive correlation coefficients with ash yield with exceptions of bi cs nb mn se and ti are grouped in other four associations group c cr v mo u cd tl group d hg li sc ti eu nb cs w group e bi sb and group f co ni cu pb zn mg se ca mn s fe the correlation coefficients of some elements including co cr cu fe hg li mo ni p s sc u v and zn with ash yield are below the statistically significant value only cr and cu are negatively correlated to ash yield 0 07 and 0 01 respectively showing intermediate organic and inorganic affinity manganese and fe are characterized by carbonate affinity probably due to high content of epigenetic veined ankerite in some coals phosphorus has low correlation coefficients with any other elements and is not included in these six associations there are five possible genetic types of enrichment of elements in coal from western guizhou province source rock volcanic ash low temperature hydrothermal fluid groundwater and magmatic hydrothermal inputs

a fresh approach to investigating co2 storage experimental co2 water rock interactions in a low salinity reservoir system the interactions between co2 water and rock in low salinity host formations remain largely unexplored for conditions relevant to co2 injection and storage core samples and sub plugs from five jurassic aged surat basin sandstones and siltstones of varying mineralogy have been experimentally reacted in low salinity water with supercritical co2 at simulated in situ reservoir conditions p 12mpa and t 60 c for 16days 384h with a view to characterising potential co2 water rock interactions in fresh or low salinity potential siliclastic co2 storage targets located in queensland australia co2 water rock reactions were coupled with detailed mineral and porosity characterisation obtained prior to and following reaction to identify changes in the mineralogy and porosity of selected reservoir and seal rocks during simulated co2 injection aqueous element concentrations were measured from fluid extracts obtained periodically throughout the experiments to infer fluid rock reactions over time fluid analyses show an evolution of dissolved concentration over time with most major e g ca fe si mg mn and minor e g s sr ba zn components increasing in concentration during reaction with co2 similar trends between elements reflect shared sources and or similar release mechanisms such as dissolution and desorption with decreasing ph small decreases in concentration of selected elements were observed towards the end of some experiments however no precipitation of minerals was directly observed in petrography sample characterisation on a fine scale allowed direct scrutiny of mineralogical and porosity changes by comparing pre and post reaction observations scanning electron microscopy and registered 3d images from micro computed tomography micro ct indicate dissolution of minerals including carbonates chlorite biotite members and to a lesser extent feldspars quantitative mineral mapping of sub plugs identified dissolution of calcite from carbonate cemented core with a decrease in calcite content from 17vol to 15vol following reaction and a subsequent increase in porosity of 1 1vol kinetic geochemical modelling of the co2 water rock experiments successfully reproduced the general trends observed in aqueous geochemistry for the investigated major elements after coupling experimental geochemistry with detailed sample characterisation and numerical modelling expected initial reactions in the near well region include partial dissolution and desorption of calcite mixed carbonates chloritic clays and annite due to ph decrease followed in the longer term by dissolution of additional silicates such as feldspars dissolution of carbonates is predicted to improve injectivity in the near well environment and contribute to the eventual re precipitation of carbonates in the far field