coal deposits as promising alternative sources for gallium abstract gallium ga which is a rare valuable metal has been found to be anomalously enriched in coal to the extent that it may be considered as an economic resource recovery of ga from coal or coal combustion byproducts offers a promising alternative way to obtain this metal and such techniques could probably lead to economic gains and positive impacts on the environment thus geochemical research and technical investigations of ga bearing coal would be helpful in assessing the potential for economic extraction of the ga the present review of ga in coal focuses on analytical methods that can be used to determine ga concentrations patterns of ga enrichment in coal and formation of economic ga enriched coal deposits modes of occurrence of ga and its origins the behavior of ga during coal combustion and gasification and currently available recovery techniques for ga moreover insufficiencies in previous research are identified and future research needs regarding ga in coal are evaluated and discussed

chemistry and origin of minor and trace elements in vitrinite concentrates from a rank series from the eastern united states england and australia abstract a rank series consisting of twelve vitrinite concentrates and companion whole coal samples from mined coal beds in the eastern united states england and australia were analyzed for c h n o ash and 47 trace and minor elements by standard elemental instrumental neutron activation analysis inaa and direct current arc spectrographic dcas techniques the reflectance of vitrinite atomic h c and o c and ash free carbon data were used to determine ranks that range from high volatile c bituminous coal to meta anthracite a van krevelen atomic h c vs o c diagram of the vitrinite concentrates shows a smooth curve having its lowest point at h c 0 18 and o c 0 01 this improves the van krevelen diagram by the addition of our vitrinite concentrate from meta anthracite from the narragansett basin of new england boron content 400 450 ppm in two illinois basin vitrinite concentrates was about an order of magnitude higher than b contents in other concentrates analyzed we attribute this to marine origin or hydrothermal activity the alkaline earth elements ca mg and ba dcas have higher concentrations in our vitrinite concentrates from bituminous coals of the appalachian basin than they do in vitrinite concentrates from the marine roofed bituminous coals of the illinois basin therefore a nonmarine origin for these alkaline earth elements is postulated for the appalachian basin coals an ion exchange mechanism due to high concentrations of these elements as ions in diagenetic water but probably not recent ground water may be responsible for the relatively high values of these elements in appalachian concentrates higher concentrations of ni and cr in one of the english vitrinite concentrates and of zr in the australian concentrate probably indicate organic association and detrital influence respectively

geochemical and petrographical characteristics of low rank balingian coal from sarawak malaysia its implications on depositional conditions and thermal maturity abstract geochemical and coal petrographical analyses were undertaken on low rank upper pliocene balingian coal from sarawak malaysia in an attempt to reconstruct the conditions during peat accumulation and the subsequent coalification processes chemically the coal in this study is characterised by high moisture low ash yield and low sulphur content the low ash yield and low sulphur content together with the lack of epiclastic partings clearly indicate that it was deposited in ombrotrophic raised bogs the coal was plotted in the type iii terrigenous kerogen zone of the van krevelen diagram with h c value below 0 9 this shows that the coal was derived from plant materials of terrigenous origin and is still immature for petroleum generation the petrographical study reveals nonetheless the expulsion of early generated hydrocarbons from the disintegration of suberinite and also from phlobaphinite and cutinite petrographically the coal is dominated by huminite with low to moderate amounts of liptinite and low amounts of inertinite pointing to predominantly anaerobic deposition conditions in the paleomires with limited thermal and oxidative tissue destruction most of the studied samples are characterised by low tpi and high gi values and are plotted on the marsh field of the diessel s diagram or it could also originate from decomposed wood in forested swamps nevertheless coals originating from both these sources usually generate high ash yield which is not the case for the studied coal this shows that the interpretation as suggested by the diessel s diagram is not valid for the studied coal the coal has a mean random huminite reflectance between 0 26 and 0 35 suggesting a lignite coal rank for the coal nevertheless geochemical classification based on total moisture and calorific value suggests a subbituminous c rank

distribution of major minor and trace elements in hat creek deposit no 2 british columbia canada abstract the major minor and trace element contents of coals from hat creek no 2 deposit british columbia are determined using inaa and inductively coupled plasma emission spectrometry boron only al cr fe mn and na were found to be inorganically bound in the coal while as b and s are associated with the organic fraction of the coal the rare earth element concentrations in the coal are variable however the lree hree ratio decreases from base to the top of the deposits many elements show little variation in concentration with depth however the gradual increase of as and s with depth appears to be rank related and indicative of progressive decrease in porosity with increasing rank concentrations of b and cr are sensitive to the environment of coal deposition with coal deposited in a freshwater environment hat creek no 2 deposit having low b and high cr compared with more brackish coals

mineralogy and geochemistry of the coals from the chongqing and southeast hubei coal mining districts south china abstract this paper deals with the study of the late permian coal deposits from chongqing and south eastern hubei mining districts and of the late triassic coal deposits from chongqing mining district the late permian coals are characterized by relatively high amount of sulphide sulphate and carbonate minerals and by a high total content of trace elements with respect to the late triassic coals due to the marine influence on the depositional environment the late permian chongqing and the southeastern hubei coals showed similar geochemistry and mineralogy however there were some differences due to the different source rock and magmatic influence on hubei coals the concentrations of most trace elements in the late triassic coal were relatively low when compared with the usual range of the worldwide concentrations by contrast the contents of ta se nb sc hf tl bi cu v and zn in the late permian chongqing and southeastern hubei coals were higher than the usual range differences in occurrence of major and trace elements were found between late permian hubei and chongqing coals thus most of the trace elements investigated presented an aluminosilicate association followed by sulphide arsenide fe s as pb mo ni and co in most cases and carbonate ca and mg affinities in both areas however there was an important phosphate and zircon association in the chongqing coal whereas the carbonate association was significantly influenced by magma in the coals from hubei in the late triassic coal most of the major and trace elements investigated occur in aluminosilicate associations with the exception of s fe ca mn sr sn ba nb mo mg co and ta with carbonate sulphate and sulphide affinities

sedimentology geochemistry and paleoenvironmental reconstruction of the cretaceous yolde formation from yola sub basin northern benue trough ne nigeria abstract sedimentology organic and inorganic geochemical studies were applied on sediments of the cretaceous yolde formation from yola sub basin northern benue trough northeastern nigeria with an attempt to determine the sedimentary facies paleo redox condition and to re construct the palaeo depositional environments eight 8 facies were identified on the basis of lithology grain size ichnofossils degree of bioturbation and sedimentary structures these facies constitute four facies associations the fa 1 offshore marine fa 2 offshore transition to lower shoreface fa 3 middle shoreface and fa 4 upper shoreface the succession of these facies associations indicates storm and wave influenced offshore shoreface depositional environments for the formation molecular organic geochemical investigation suggests deposition under sub oxic marine environment with major contribution of phytoplankton bacteria and minor amount of terrigenous organic matter xrd mineralogical assessment and major and trace elements geochemistry revealed that the yolde formation sediments were sourced from continental areas of passive continental margin setting and deposited in semiarid climate under suboxic shallow marine conditions related to the first marine transgression that occurred in the benue trough during the late cretaceous period

geochemical distribution of trace elements in kaffioyra and longyearbyen coals spitsbergen norway abstract paleogene bituminous coals of low rank r aver 0 63 and 0 69 respectively occurring in two spitsbergen norway regions longyearbyen and kaffioyra were analyzed to find occurrence and distribution of the following trace elements be cd co cr cu li mn mo ni pb v zn inductively coupled plasma atomic emission spectrometry icp aes was used for ash derived from combusted coals their extracts and macromolecular fractions trace element concentrations were investigated to find occurrence variability and a degree of trace element affinity to organic and inorganic coal fraction in the coals from both regions maceral and elemental composition of these coals was also determined kaffioyra and longyearbyen coals show significant differences in the composition of their organic and mineral matter reflected both in petrographic properties and elemental compositions the kaffioyra coals are characterized by higher contents of vitrinite group macerals lower contents of inetrinite group macerals and lower concentrations of carbon hydrogen and sulphur the kaffioyra coals show higher content of clay minerals and carbonates than the longyearbyen coals trace element contents in ash of coals from both spitsbergen regions are below the average contents of these elements in the world s bituminous coals coals of both regions differ in trace element concentration and their occurrence variability the main carrier of trace elements in coals of both regions is ash of biogenetic and sorptive origin while in the range of high concentrations of trace elements terrigenic input also plays an important role

trace elements in the lower pliocene fossiliferous kangal lignites sivas turkey abstract the kangal lignite basin which is one of the most productive lignite basins in eastern anatolia turkey includes two lignite seams containing abundant gastropoda shells in the lower pliocene kalburcayiri formation the seams are currently exploited in an open cast mine in the kalburcayiri field and supply feed coal to a power plant with 300 mw capacity the average thickness of each of the two seams in this mine is about 10 m and they are separated by about 20 m of tuffaceous sedimentary rocks a 15 20 cm thick tuff bed occurs within the upper seam the purpose of the study was to understand mineralogy and trace element concentrations of the two lignite seams in the kalburcayiri formation which were affected by volcanic ashes fifty nine core samples of the lignites from seven boreholes across the basin and eight channel samples from the working lignite seams were collected and analysed by proximate analysis x ray powder diffraction xrd inductively coupled plasma mass spectrometry icp ms and scanning electron microscopy sem with energy dispersive x ray microanalysis techniques the samples show that the worked lignite seams on an as received basis contain high moisture contents 43 4 57 8 all the samples on an air dried basis have high ash yields from 19 5 to 81 7 and a broad range of total sulfur contents from 1 16 to 7 04 and calorific values 684 to 4621 kcal kg except for two samples with no temperature rise due to high ash yield the mineral matter of the studied samples is made up of calcite quartz feldspar pyrite opal ct clay minerals gypsum and traces of aragonite the trace element analyses on a whole coal dry basis indicate that most of the borehole samples showed enrichment in specific elements including zn 15 1394 g g mo 13 368 g g and u 5 5 131 g g when compared to the range of these elements for most coals in the world the contents of zn mo and u for the samples from the worked lignite seams are respectively 38 187 54 161 and 28 55 g g the sem studies show that zn is hosted mainly in micron sized zn bearing mineral sphalerite but no mo and u bearing minerals have been detected during these studies except for monazites containing th and u traces the mo and u concentrations are negatively correlated with the ash yields and these elements are contained mainly within organic matter

significant enrichment of ga rb cs rees and y in the jurassic no 6 coal in the iqe coalfield northern qaidam basin china a hidden gem abstract this paper presents new data concerning the mineralogy and trace element geochemistry of the enriched rare metals in the jurassic no 6 coal from the iqe coalfield qaidam basin china the conclusions of this study are based on new data and evidence that suggest the considerable enrichment of ga rb cs rees and y in the no 6 coal of the iqe coalfield may be a hidden treasure with yet to be realized additional economic potential if such rare metal enrichment is proven across the whole area of iqe coalfield the no 6 coal is enriched in al 2 o 3 sio 2 na 2 o mgo p 2 o 5 k 2 o tio 2 rb cs ga sc v cr cu ba w pb th and rey especially in ga rb cs and h rey compared to world coals the average contents of ga cs rb and rey are 3 1 12 3 6 0 and 3 5 times higher than those of world bituminous coals respectively ga may occur in clay minerals e g kaolinite particularly in k rich clay minerals e g illite which are thought to be derived from the qilian mountain range these minerals are probably the hosting phases for both rb and cs in the coal studied rees and y in the coal are more likely to be associated with phosphates the combustion products e g fly and bottom ash derived from those coals may be further enriched in these valuable rare metals and have economic potential in terms of the recovery of ga rb cs rees and y providing additional economic value to this coal deposit

some considerations concerning the use of correlation coefficients and cluster analysis in interpreting coal geochemistry data the mode of occurrence of trace elements in coal is important from both scientific and environmental viewpoints because the behavior of trace elements in coal utilization depends not only on their concentration but also on their chemical form or mode of occurrence statistical methods are one of the more commonly used indirect approaches for interpreting element modes of occurrence these methods include correlation coefficients between elements and ash as well among the elements themselves cluster and factor analysis using data sets derived from a suite of 75 samples from a bulgarian lignite deposit we demonstrate that statistical analysis of subsets with different ash ranges and with slightly different suites of elements can lead to substantially different conclusions concerning the element modes of occurrence in this example we assume that direct information on the element modes of occurrence such as mineralogy or selective leaching behavior is absent statistical methods however can provide useful insights into trace element modes of occurrence for properly constrained sample suites

a preliminary study of mineralogy and geochemistry of four coal samples from northern iran abstract this study is related to four jurassic age bituminous coal 0 69 1 02 ro samples collected from coal mines from the west central and east of central alborz in northern iran geological settings played key roles in determining the geochemistry and mineralogy of coals from the central alborz region of northern iran the mineralogy of coals from the eastern part of the region is dominated by kaolinite halloysite and carbonates such as calcite dolomite ankerite and siderite the coals were deposited in a lacustrine environment in the western part of the region where the depositional setting was also lacustrine with volcanic input and tonstein deposition glass shards present the coal primarily contains kaolinite 68 and fluorapatite 26 in contrast coal from the central part of the region which was deposited in a terrestrial environment and on eroded limestone and dolomite rocks is dominated by dolomite 98 with little input by kaolinite these coals have low sulphur 0 35 0 70 wt which is mostly in the organic form 0 34 0 69 wt pyritic sulphur is detected only in one coal and in small quantities the boron contents of these coals range from 9 to 33 mg kg indicating that deposition occurred in a fresh water environment coal with higher concentrations of ba sr and p contain fluorapatite and goyazite gorceixite series baal 3 po 4 2 oh 5 h 2 o minerals which indicates volcanoclastic input compared to world coal averages these coals exhibit low concentrations of elements of environmental concern such as as 1 3 5 9 mg kg cd

proterozoic mineral deposits near plate margins of the archean wyoming province usa abstract proterozoic mineral deposits located near the margin of the archean wyoming province can be interpreted in a plate tectonic context the southern margin of the archean wyoming province is exposed in southeastern wyoming where early proterozoic island areas have been sutured to an early proterozoic passive margin developed during rifting of the archean wyoming craton mineral deposits include uranium thorium gold bearing quartz pebble conglomerate deposited during rifting stratiform sulphide in black shale of the foredeep basin anomalous platinum group element values in layered complexes of the island arcs and a variety of mineral deposits that formed during closure of the arcs and passive margin the eastern margin of the wyoming province is probably located under phanerozoic cover just east of the black hills of south dakota the black hills is a segment of the early proterozoic trans hudson orogen which is interpreted here as an area exhibiting evidence of opening and closing of an intracratonic basin in the black hills domes underlain by archean rocks are overlain by an early proterozoic clastic successions that preserves evidence of rifting these clastic successions are succeeded by marine quartzite which is in turn overlain by a eugeosynclinal succession containing iron formation graywacke and a variety of volcanic units the basal early proterozoic clastic succession contains uranium and gold bearing quartz pebble conglomerate formed during rifting the eugeosynclinal succession contains the homestake iron formation which is host to the early proterozoic homestake type gold deposits geologic and geochemical evidence can be marshalled to support either an epigenetic or syngenetic origin for the homestake type gold deposits if the gold deposits are syngenetic they may have formed in a foredeep basin developed during closure of the intracratonic basin

precambrian basement structure and laramide deformation revealed by seismic reflection profiling in the laramie mountains wyoming the university of wyoming conducted seismic reflection profiling in the laramie mountains of wyoming to investigate the nature of precambrian crustal structure and laramide deformation in the region here the imaging of layering in the laramie anorthosite complex confirms that layered intrusions can be reflective and establishes an analog for interpreting events in other seismic reflection data sets where layered intrusions could be the cause of multicyclic events moreover the presence of prominent primary layering in the complex supports a conclusion that it formed in situ and not as the result of the emplacement of a diapiric crystal mush imaging of laramide thrusts in the laramie mountains adds credence to the idea that brittle faults can be reflective in some situations migrated apparent dips on these faults are 30 westward basement involved compressive structures consisting of monoclinal folding and a fault triple junction demonstrate that compression controlled the style of deformation during the laramide orogen in wyoming west dipping precambrian structures imaged in these data have a similar attitude to the laramide structures suggesting that laramide deformation was influenced by precambrian features these precambrian structures may be subthrust slices of exotic proterozoic terranes

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 of boron in bulgarian coals a set of 466 individual full channel samples coals coaly shales and partings of thirteen bulgarian coal deposits as well as vitrain lenses gagatite and coalified woods embedded in sedimentary rocks have been analyzed by atomic emission spectroscopy the deposits consist of lignites subbituminous and bituminous coals the average boron content ranges from 15 to 164 ppm in the coals the boron content of the individual coal samples ranges from 2 to 164 ppm about 86 of the samples have a b content from 2 to 110 ppm which corresponds to the most probable interval of concentration for coals worldwide the boron content is not related to rank the lignites have the lowest boron content some of the vitrain and xylain samples studied are enriched in boron in comparison with the whole coal samples boron occurs in both organic borg and inorganic binorg forms excluding one deposit the boron content in the ash correlates negatively with the ash content whereas in coals it usually slightly increases with increasing ash content organically associated b dominates in the low ash coals and in the deposits enriched in boron the coals of the burgas deposit have the highest b content which is in agreement with the geological evidence for marine influence during the early stages of coalification the distribution of b is also independent of other geological factors

concentration distribution and modes of occurrence of selenium in huaibei coalfield anhui province china selenium a toxic element is highly enriched in the coals of the huaibei coal deposit china for this study se content along with rock forming and trace element abundances was determined in 123 coal and 19 rock samples collected from the main coal seams in seven coal mines in the huaibei coalfield this was done to investigate the se geochemistry in the huaibei coals compared with average chinese coal and other coals around the world the huaibei coals are enriched in se by a factor of five differences in the boron content in the sequence of huaibei coal seams show that the depositional environment of the formations hosting the coal seams evolved from a delta front to a prodelta setting and then to a delta plain environment selenium is distributed unevenly both horizontally and vertically in the huaibei coal deposit pearson correlation coefficients between se with several elements ca fe and s indicate that iron bearing clay minerals and carbonates are the dominant carriers of se in coals of the lower shihezi formation selenium in coals from no 3 and no 10 coal seams are mainly associated with sulfide minerals the well developed faults in huaibei coalfield may have contributed to the enrichment of se in huaibei coals

trace elements geochemistry of the dobrudza coal basin bulgaria abstract the paper discusses the abundance mode of occurrence and origin of trace elements in the dobrudza coal deposit the deposit is the deepest in bulgaria it is overburden by paleozoic up to cenozoic sediments of 1300 m to 1600 m thickness the coal rank reaches the stage of high volatile a bituminous coal the contents of ba cl br mn ge pb w mo as zr li cs cu zn sb ti v th u ag be and y are enriched from 1 5 to 9 2 times as compared with the clarkes for bituminous coals the content of the other elements are slightly higher lower than the respective world wide means chondrite normalized patterns of the ree reveal a strong fractionation among the hree and lree most pronounced for the coals than for the coaly shales and partings a specific feature is the small eu anomaly in the shales and the tonsteins underlying the coal bed most elements are of mixed organic and inorganic association ge cl br mo be and au are predominantly bound to the organic matter arsenic correlates strongly with fe suggesting presence in pyrite ba occurs mainly as barite which is most probably of epigenetic origin sr and mn are presented mainly as isomorphous admixtures in barite and calcite the abundance of the lithophile elements excluding ge mo ba cl br is controlled largely by the detrital and clay mineral content of the coals many elements of different groups correlate positively each other calculation of partial correlation coefficients excluding ash shows that many of these correlations are spurious due to the positive correlation of every single element with ash for this reason the correlation coefficients must be critically evaluated when deducing the mode of occurrence of elements the accumulation of the trace elements in the dobrudza coals was influenced by multi component geological factors 1 as a result of upper pennsylvanian volcanism there are widespread tonsteins underlying the coal layers and as thin layers in the coal most likely many elements were leached from the tonsteins and trapped by the coal 2 olivinobasalt and andesito basalt dikes intruding the coal bearing sediments may cause enrichment or depletion of many elements 3 highly mineralized underground waters are the source of cl br b sr and probably some other elements 4 the numerous regional faults favor the penetration of solutions of different origin which were carriers of trace elements 5 postgenetic erosive processes may cause leaching of trace elements from the rocks which are consequently fixed by the coal

geochemistry of trace elements in coals from the zhuji mine huainan coalfield anhui china the abundances of nine major elements and thirty eight trace elements in 520 samples of low sulfur coals from the zhuji mine huainan coalfield anhui china were determined samples were mainly collected from 10 minable coal seams of 29 boreholes during exploration the b content in coals shows that the influence of brackish water decreased toward the top of coal seams marine transgression and regression occurred frequently in the lower shihezi formation a wide range of elemental abundances is found weighted means of na k fe p be b co ni cr se sb ba and bi abundances in zhuji coals are higher and the remainder elements are either lower or equal to the average values of elements in coals of northern china compared to the chinese coals the zhuji coals are higher in na k be b cr co se sn sb and bi but lower in ti p li v and zn the zhuji coals are lower only in s p v and zn than average u s and world coals potassium mg ca mn sr as se sb and light rare earth elements lree had a tendency to be enriched in thicker coal seams whereas fe ti p v co ni y mo pb and heavy rare earth elements hree were inclined to concentrate in thinner coal seams the enrichment of some elements in the shanxi or upper shihezi formations is related to their depositional environments the elements are classified into three groups based on their stratigraphic distributions from coal seams 3 to 11 2 and the characteristics of each group are discussed lateral distributions of selected elements are also investigated the correlation coefficients of elemental abundances with ash content show that the elements may be classified into four groups related to modes of occurrence of these elements

mineral matter major and trace element content of the afsin elbistan coals kahramanmaras turkey abstract the afsin elbistan coal basin is one of the most important coal deposits of turkey the mineral matter major and trace element concentrations of the afsin elbistan coals and their modes of occurrence are discussed in this study the coal seam is located within the upper miocene pliocene aged ahmetcik formation which is represented by fluvial lacustrine facies thickness of the coal zone is 80 m but it reaches 105 m in the kislakoy sector a total of 86 samples were taken from the kislakoy open pit mine and from the 14 boreholes drilled by the general directorate of mineral research and exploration mta for coal exploration the proximate xrd sem eds major and trace element analyses were conducted on the samples the studied coals are characterized by relatively high moisture ash total sulfur volatile matter contents and low gross calorific values the mineral matters of the afsin elbistan coal are represented by calcite quartz pyrite feldspar aragonite opal ct gypsum jarosite and clay minerals strontium rb sm zr hf nb mo u zn pb as mn co cr and ni concentrations detected by edp xrf are higher than the world brown coal values many of the trace elements showing positive correlations with ash content imply inorganic affinity the element concentrations of the coals are mainly related to the carbonate silicate sulfide phosphate ore minerals and fossil shells however some elements have also organic affinities

the geochemistry of environmentally important trace elements in uk coals with special reference to the parkgate coal in the yorkshire nottinghamshire coalfield uk abstract the parkgate coal of langsettian age in the yorkshire nottinghamshire coalfield is typical of many coals in the uk in that it has a high sulphur s content detailed information on the distribution of the forms of s both laterally and vertically through the seam was known from previous investigations in the present work 38 interval samples from five measured sections of the coal were comprehensively analysed for major minor and trace elements and the significance of the relationships established using both raw and centered log transformed data the major elements are used to quantify the variations in the inorganic and organic coal components and determine the trace element associations pyrite contains nearly all of the hg as se tl and pb and is also the major source of the mo ni cd and sb the clays contain the following elements in decreasing order of association rb cs li ga u cr v sc y bi cu nb sn te and th nearly all of the rb is present in the clay fraction whereas for elements such as v cu and u a significant amount is thought to be present in the organic matter based on the k vs trace element regression equations only ge and possibly be would appear to have a dominant organic source the trace element concentrations are calculated for pyrite the clay fraction and organic matter for pyrite it is noted that concentrations agree with published data from the yorkshire nottinghamshire coalfield and also that tl concentrations median of 0 33 ppm in the pyrite are greater than either hg or cd unlike these elements tl has attracted less attention and possibly more information is needed on its anthropogenic distribution and impacts on man and the environment a seawater source is thought to be responsible for the high concentrations of s cl and the non detrital trace elements in the parkgate coal indicative of the seawater control is the th u ratio which expresses the detrital to non detrital element contributions using other elements similar ratios can be calculated which in combination offer greater interpretative value

major trace and platinum group element geochemistry of the upper triassic nonmarine hot shales in the ordos basin central china abstract the upper triassic chang 7 non marine hot shales have been proven to contribute to mesozoic oil reservoirs in the ordos basin central china these shales have been studied extensively in sedimentology petrology and organic geochemistry however the factors controlling the development of the shales are still ambiguously constrained this paper presents the major trace and platinum group elements pges data to address these issues the chemical index of alteration cia chemical index of weathering ciw c values and clay mineral compositions indicate that the chang 7 hot shales were developed in a humid paleoclimate the indicators of redox conditions eu eu ce ce ce anom u u th v v ni and v cr suggest that the chang 7 hot shales were developed under anoxic environment uranium enrichment average 46 10 ppm is an important distinguished signature of the chang 7 hot shales which was mainly related to synchronous volcanic ash sediments and or possibly hydrothermal fluids the pge concentrations of the chang 7 hot shales were reported for the first time here and can be subdivided into two groups the total abundances of the group one samples are relatively lower and derived mainly from detrital minerals while the group two samples are relatively higher and are also likely linked to the synchronous volcanic ash sediments and or possibly hydrothermal fluids combined with the regional geological setting we tentatively propose that the tectonics is the major control on the development of the chang 7 hot shales

geological controls on the sulphur distribution in british carboniferous coals a review and reappraisal abstract the very extensive literature on sulphur in peats and coals is reviewed and four case histories from british coalfields are considered in the parkgate seam langsettian from the nottinghamshire coalfield the variation in the total sulphur content is attributed to pyritic sulphur with organic sulphur also significant but showing a smaller variation sulphate sulphur is negligible there is a spatial variation in the sulphur concentrations in individual sections plies of the parkgate seam but this is unrelated to other sections of the seam and to identifiable post depositional controls thereby providing indirect evidence of a depositional control on sulphur incorporation in the main bright duckmantian north derbyshire coalfield and threequarters seams langsettian north derbyshire nottinghamshire coalfields the depositional control is shown to be related to contemporaneous channels there is a hierarchy of channels and it is concluded that these provided access of more saline waters into the peat mire coals associated with marine bands often show high sulphur contents but there are exceptions particularly in the scottish namurian as exemplified by the upper hirst seam where it is thought that there was no contemporary ingress of saline waters three westphalian depositional provinces are recognised on the basis of channel sandstone loci and there is the possibility that different source areas influenced the salinity sulphate content in the mires there is some evidence of regional differences in the sulphur content of british coals which is consistent with the distribution of the three provinces on the other hand there is irrefutable evidence that access of seawater leads to high sulphur coals and possibly the marine influence was more pervasive than is generally recognised there is supporting geochemical evidence of enrichment of trace elements in coals which is indicative of a seawater source

early proterozoic tectonics and metallogeny of the lake huron region of the canadian shield abstract deposition of the huronian supergroup dominantly fluvial clastic sediments with local basal volcanic accumulations began at 2 49 ga in a broad trough that extended far south of the present lake huron area atop a large archean continent that was assembled at 2 7 ga and broken up at 2 15 ga after intrusion of widespread gabbro sheets and dykes including nipissing diabase the wyoming province which contains sequences similar in age and stratigraphy to the distinctive huronian supergroup may be a fragment of this continent the superior province is a much larger fragment tectonic controls of deposition of the huronian and its paleoplacer uranium deposits and of the pre 2 2 ga deformation of these strata were probably unrelated to processes that controlled deposition of the animikie and marquette range sequences in the lake superior region at 2 0 ga the huronian animikie and marquette range sequences were deformed during the 1 85 ga penokean orogeny which occurred when an assembly of island arc terranes collided with the superior block the sudbury structure including the whitewater group and its contained sedex deposits and the sudbury igneous complex and its ni cu pge ores were also formed at 1 85 ga the elliot lake pyritic paleoplacer uranium ores myriad lenses of radioactive pyritic gravels were deposited by early huronian fluvial systems other endogenic huronian mineral deposits include disseminated ni cu sulphides in gabbros cu in red beds high in the huronian succession and silica in quartz arenites intrusions of nipissing gabbro near sudbury contain minor ni cu mineralization these intrusions also caused recycling of metals from archean and huronian rocks to form concentrations of cu au ag fe and w in veins and other epigenetic deposits most important of these are the unconformity related ag veins of the cobalt area which had particularly complex still undeciphered histories that probably included pre huronian weathering metallogenic patterns in the early proterozoic rocks were controlled by a complex interplay of factors including the distribution of mineral deposits in the archean basement tectonically controlled variations in huronian deposition and deformation and oxyatmoversion the transition from anoxic to oxygenic atmospheric conditions that occurred during deposition of the huronian supergroup

geochemical characteristics of the silurian shales from the central taurides southern turkey organic matter accumulation preservation and depositional environment modeling abstract the silurian age organic rich and organic lean shales located within aydincik gulnar and silifke districts of mersin province in central taurides southern turkey is considered as an unconventional resources these organic rich and lean shales are controlled by the similar geological tectonic and sedimentary processes as the passive margin basin has acted as the provenance region throughout the deposition of these shales geochemical data of major and trace elements obtained for a total of 39 outcrop samples were interpreted to determine the depositional model water column productivity amount of organic matter and preservation conditions total organic carbon toc values of these organic rich and lean shales range from 0 56 to 4 06 wt and 0 01 to 0 38 wt several redox indicators such as v systematics v sc v ni as well as ratios of ni co th u and mo mn showed that the organic rich shales were deposited in suboxic to anoxic environments as opposed to oxic dysoxic conditions for organic lean ones however organic matter enrichment is not restrained by water column productivity as indicated by a lack of correlation between toc and productivity indexes p ti and ba al but rather probably controlled by dysoxic anoxic water column environment in addition a detrital material input cannot be ignored for its influence on organic matter enrichment in the shale deposition the increase in the clastic fluxes probably resulted from the deposition in the extended shelf with coastal upwelling a lack of correlation between k2o al2o3 sio2 and toc contents among these shales imply that clay minerals may not influence organic matter preservation according to w la n w yb n and ree values a high sedimentation rate is determined during the shale deposition which would result in a dilution of organic matter furthermore slight marine influences with sulphur limitation and low salinity semi arid warm to humid warm climatic conditions are widespread according to total sulphur ts sr ba sr cu chemical index of alteration cia c value and related discrimination diagrams in the end a depositional model of the central taurides shales is established to display an excellent preservation condition as the major controlling factor for organic matter enrichment in the silurian shales

petrographic mineralogical and geochemical characterization of the serrinha coal waste pile douro coalfield portugal and the potential environmental impacts on soil sediments and surface waters abstract serrinha is the largest coal waste pile resulting from mining activities in the douro coalfield portugal the exploitation of anthracite in tens of small mines caused some environmental impacts as is the case of the coal waste piles that exist in old mines and adjacent areas the serrinha waste pile is essentially made up of 2 million tonnes of shales and carbonaceous shales deposited in a topographical depression over about 30 years despite the environmental restoration accomplished in the serrinha waste pile some environmental problems seem to persist in this study a petrographic mineralogical and geochemical characterization was done in order to recognize and understand these problems the materials studied were coal waste sediments and waters from the drainage system and decanting basins soils from the surrounding areas leachates from waste material and neoformed minerals formed at the bottom of the waste pile the main lithologies carbonaceous shale and lithic arenite and coal from the douro coalfield were also analyzed petrographic analysis shows some evidence of weathering on organic and inorganic matter related to the time of exposure to the weathering agents and the easy access of air within the waste pile due to both the poor compaction and the heterogeneity of the material mineralogically the composition of coal waste material has contributions from both the coal and the associated lithologies r type cluster analysis of the waste pile material allows two distinct clusters to be identified in the first cluster a sulfide fraction is represented by the association of as cd cu pb ni and zn while fe clustered with al co and ti indicates that some of the fe and the other elements are likely associated with silicate minerals such as clays the second cluster represented by cr v zr rb ree mn li and ba probably represent a silicate fraction perhaps detrital accessory minerals the waste pile material leachates soils sediments neoformed minerals and water analyses indicate the existence of potential environmental impacts due to the acid mine drainage and associated leaching of heavy metals and other elements

on the geological availability of germanium based on a detailed statistical analysis of chemical data published in the scientific literature estimates were made of the minimum amounts of recoverable ge contained within sulphidic zinc ores and coals given current processing technologies it is expected that at least 119 kt 7 kt in zinc ores and 112 kt in coal of recoverable germanium exist within proven reserves at present stage of knowledge at grades in excess of 100 ppm in sphalerite and 200 ppm in coal while at least 440 kt 50 kt in zinc ores and 390 kt in coal should become recoverable in the future being associated to coal reserves at 8 200 ppm ge and zinc resources containing in excess of 100 ppm ge in sphalerite mississippi valley type mvt deposits are expected to be the most important hosts of germanium rich sphalerite while both brown and hard coals are expected to be equally important as hosts of germanium the approach taken in this publication shows that reliable minimum estimates for the availability of by product metals lacking suitable reserve resource data may be attained by using robust statistical methods and geochemical data published in the scientific literature

a new view of an old suture zone evidence for sinistral transpression in the cheyenne belt the type locality of the archean paleoproterozoic suture zone in the southern rocky mountains is marked by a series of subvertical shear zones collectively called the cheyenne belt the cheyenne belt is a key structure for developing models for 1780 1740 ma tectonism along the southern margin of the archean wyoming province which heralded a rapid period of continental amalgamation this paper tests existing structural and plate tectonic models for the cheyenne belt with detailed geologic mapping kinematic analyses quartz crystallographic fabric analyses and deformation mechanism analyses of the northern mylonite zone of the eastern medicine bow mountains mylonites of this zone record a complex deformation history but the main deformation phase was sinistral northwest side up oblique transpression evidence for southeast side up dip slip motion that characterizes many other areas of the belt is confined to ultramylonites immediately adjacent to the terrane boundary hence fabrics related to sinistral transpression were likely overprinted by southeast side up motion sinistral strike slip motion is recorded in at least two other localities in the cheyenne belt because synmetamorphic fabrics on both sides of the suture zone record sinistral strike slip and northwest side up motion this was probably the dominant deformation style in the field area and may have been the dominant deformation style throughout the cheyenne belt based on these data and regional constraints we interpret the cheyenne belt as a subvertical transpressional stretching fault system that simultaneously accommodated sinistral strike slip motion penetrative horizontal shortening and dip slip motion related to differential crustal thickening between the relatively cold wyoming province and younger hotter rocks to the south

mineral matter and trace elements in coals of the gunnedah basin new south wales australia abstract the concentrations of major and trace inorganic elements in a succession of permian coals from the gunnedah basin new south wales have been determined by x ray fluorescence techniques applied to both whole coal and high temperature ash samples the results have been evaluated in the light of quantitative data on the minerals in the same coals determined from x ray diffraction study of whole coal samples using a rietveld based interpretation program siroquant to determine relationships of the trace elements in the coals to the mineral species present comparison of the chemical composition of the coal ash interpreted from the quantitative mineralogical study to the actual ash composition determined by xrf analysis shows a high degree of consistency confirming the validity of the xrd interpretations for the gunnedah basin materials quartz illite and other minerals of detrital origin dominate the coals in the upper part of the sequence whereas authigenic kaolinite is abundant in coals from the lower part of the permian succession these minerals are all reduced in abundance however and pyrite is a dominant constituent in coals formed under marine influence at several stratigraphic levels calcite and dolomite occur as cleat and fracture infillings mostly in seams near the top and bottom of the sequence the potassium bearing minerals in the detrital fraction are associated with significant concentrations of rubidium and the authigenic kaolinite with relatively high proportions of titanium zirconium is also abundant with associated p and hf in the gunnedah basin coal seams relationships exhibited by ti zr nd and y are consistent with derivation of the original sediment admixed with the seams from an acid volcanic source pyrite in the coals is associated with high concentrations of arsenic and minor proportions of thallium no other element commonly associated with sulphides in coals however appears to occur in significant proportions with the pyrite in the sample suite small concentrations of cl present in the coal are inversely related to the pyrite content and appear to represent ion exchange components associated with the organic matter strontium and barium are strongly associated with the cleat filling carbonate minerals ge and ga appear to be related to each other and to the coal s organic matter cr and v are also related to each other as are ce la nd and pr but none of these show any relationship to the organic matter or a particular mineral component

the influence of geological factors on the concentration of boron in australian and canadian coals abstract the concentration of boron in australian and canadian coals determined using atomic emission spectrometry aes inductively coupled plasma spectrometry icp aes and prompt gamma ray spectrometry is summarized in order to assess the variation of b content in coal with respect to rank age geological setting in seam and stratigraphic and the degree of paleosalinity of the coal forming environment this study indicates that no or very complex relations exist between boron and rank subbituminous to anthracite variations of b with ash content for canadian coals of different age devonian to oligocene eocene indicate that the b content of coals is not governed by the age of the coal there is some evidence of variation of b with maceral content in canadian coals particularly as related to the inertinite and vitrinite content of coals the b content of coal seams is sensitive to the environment of deposition with b contents remaining relatively stable and within the range of values designated for each depositional setting however b values may show variation in the same seam laterally due to changes of the environment of deposition and or the enrichment of b by a secondary source the vertical variation of b in a coal bearing section or strata is related to depositional environment and lithology of rock there is often little variation in b content for coal layers as compared to the partings dirt bands the b content of partings in a coal bearing strata may vary greatly as compared to the coal seams after reappraising earlier work and on the basis of more recent studies on australian and canadian coals it is proposed that the following ranges of values for b in coal indicate the degree of marine influence during the early stages of coalification up to 50 ppm b freshwater influenced coals 50 110 ppm b mildly brackish water influenced coals 110 ppm b brackish water influenced coals using these criteria assessments are given for the degree of marine influence on canadian and australian coals

mode of occurrence of trace elements in the pellana lignite se peloponnese greece mineralogical and geochemical analyses of the pellana lignite se peloponnese greece were carried out in order to predict the mode of occurrence of trace elements and their mobility during lignite combustion for power generation lignite and ash samples after combustion at 750 c of two cores from this deposit were examined the mean ash content is 30 to 43 and c contents on dry ash free basis range from 45 to 60 respectively the mineral phases contained in the lignite are quartz k feldspars mixed layer clays illite rich micas gypsum and pyrite factor analysis on geochemical data shows that the elements as ba mn mo sb se sr u and v have both organic and inorganic affiliation to study the mobility of each element during combustion the relative enrichment factor was calculated the most depleted and hence the most mobile elements proved to be hf nb and sb while se ba and bi are moderately depleted in case of the pellana lignite utilization we should expect environmental problems associated with the elements as ba bi hf mn mo nb sb and se these elements may be either volatilized during combustion or leached from fly ash disposal areas into underground waters causing severe environmental and health impacts

the tampere schist belt structural style within an early proterozoic volcanic arc system in southern finland abstract the central part of the narrow e w trending tampere schist belt comprises volcanic and sedimentary rocks of low metamorphic grade surrounded by intrusive rocks and migmatites the first folding event with subvertical axial surfaces and originally subhorizontal fold axes dominates the structure of the belt well preserved primary structures indicate a major e w trending syncline in the northern part of the belt with minor upright open to tight synclines and anticlines in the limb areas f 1 fold axes in the limbs have been rotated towards the steeply to vertically plunging stretching lineation dextral f 2 folds with subvertical e w to ne sw striking s 2 crenulation cleavage and steeply plunging fold axes overprint penetrative s 1 schistosity subhorizontal dextral shear is inferred from the d 2 structures d 3 kinking and fracturing is restricted to narrow nw se to n s trending zones the shear zone between the schists and the migmatites to the south is a south dipping thrust or reverse fault with uplift of the higher grade rocks in the northern part of the tampere schist belt another major fault is postulated both shear zones were formed at a late stage of progressive d 1 deformation on the basis of these structures and published sedimentological geochemical and isotopic data the tampere schist belt is interpreted as an upper part of a thrust sheet within a forearc of an ancient volcanic arc system the vergence of structures suggests subduction toward the present south

seismic wide angle study of accreted proterozoic crust in southeastern wyoming abstract a seismic wide angle experiment was conducted in southeastern wyoming usa to investigate the seismic character of a postulated proterozoic magmatic arc south of the suture cheyenne belt to the archean wyoming province recordings from vibrator and dynamite sources with offsets between 34 and 126 km reveal no evidence for moho reflections the large offset recordings contain multicyclic bands of reflective phases from the middle to lower crust the data were transformed into the intercept time ray parameter p domain to estimate local depth bounds a subsequent 1d inversion using high amplitude p arrivals shows that the reflective part of the crust ranges from the depths of 25 to 40 km this part of the crust exhibits velocities increasing from about 6 5 to 7 5 km s reflectivity modeling shows that the lower crust might consist of a zone of alternating low and high velocity layers with average velocity increasing the average lower crustal velocity of about 6 9 km s suggests a predominantly mafic composition with interlayered intermediate to felsic components generating impedance contrasts that cause observable amplitudes from reflections at large offsets but not at clearly pre critical and near vertical distances our model is consistent with observations of interlayered sequences of gabbroic to ultramafic rocks with more felsic anorthositic and charnockitic rocks in the exposed lower crust of magmatic arc complexes the lack of wide angle moho reflections might be explained by a gradational compositional boundary or a transitional phase change from granulite to eclogite facies

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

minerals and potentially hazardous trace elements in marine oil shale new insights from the shengli river north surface mine northern tibet china the shengli river changshe mountain oil shale zone including the changliang mountain shengli river oil shale the shengli river north oil shale and the changshe mountain oil shale represents potentially the largest marine oil shale resource in china new geochemical data from the shengli river north oil shale are presented to evaluate potentially hazardous trace elements in oil shale and to discuss possible factors controlling the geochemical anomalies oil shale samples from the shengli river north area are characterized by high ash yield 59 25 66 27 and toc content 4 77 9 35 with low total sulfur content 0 1 1 56 and intermediate shale oil content 3 60 16 30 minerals in the shengli river north oil shale include calcite clay minerals quartz dolomite and fe bearing minerals e g pyrite limonite and hematite and trace amounts of zeolite apatite and barite potentially hazardous trace elements in oil shale samples include as se mo f ni cd and hg arsenic is present probably in both organic and inorganic matter selenium is controlled mainly by fe bearing probably pyrite while f and cd occur mainly as apatite the organically bound mo and ni are dominant and hg probably occurs as a substitution in the structure of pyrite apatite and calcite the elevated concentrations of f and cd in the shengli river north oil shale may be related to sediment source water chemistry may have played an important role for ni and mo enrichments while the enrichment of se in the oil shale samples is possibly related to hydrothermal fluids other elements including hg and as are probably related to several factors

geochemical data as indicators of palaeosalinity in coastal organic rich sediments abstract a geochemical study of extractable major minor and trace elements peatlands from e spain elucidated variations in salinity related to the interpretation of relative sea level change samples were taken from different peatlands from the subsiding valencia castellon quaternary basin e spain these correspond to back barrier marshes with brackish and freshwater influence containing carex juncus typha and phragmites samples from a highland sphagnum moss freshwater peat bog were also included for comparison this paper categorizes palaeosalinity indicators in this coastal peat deposits as follows b br i na s ge u this compares with low rank coal which shows the following relationship b br i s na ge u the formulation of an index for characterising the organic detrital content using k or al concentration is also proposed this resulted in the following salinity index for peat b k br k i k na k s k ge k u k and for low rank coal b k br k i k s k na k ge k u k

geochemical characteristics redox conditions and organic matter accumulation of marine oil shale from the changliang mountain area northern tibet china abstract the organic rich changliang mountain oil shale located in the north qiangtang depression northern tibet is considered to be excellent mineral resource in china the changliang mountain oil shale reported here was deposited in a tidal flat lagoon environment and is characterized by black thin layered oil shales intercalated with dark gray marls here we present geochemical data from the changliang mountain oil shale profile in order to investigate the mechanism of organic matter om accumulation and to establish the formation model for the marine oil shale deposition total organic carbon toc values range from 2 96 to 23 47 in the oil shale samples while the marl samples contains low toc contents ranging from 0 06 to 0 21 in the organic rich oil shale sediments many redox indicators including mo al ratios v cr ratios th u ratios ni co ratios and the relationship of mo to toc suggest a deposition under dysoxic to anoxic environments subsequently the bottom water evolved into an oxic water body when the organic poor marls were deposited however the negative and or weak relationship between toc and productivity indices p ti and ba al indicates that om accumulation was not controlled mainly by primary productivity but dysoxic anoxic bottom water environment a stratified water column may be initiated by the supply of fresh water from the continent nearby combining with warm and humid climate which is beneficial to the reproduction of marine organisms the death and bury of these organisms could lead to the formation of dysoxic anoxic bottom waters and enhance the preservation of om in this study a preservation model of the changliang mountain oil shale was established the model implies that excellent preservation is the major controlling factor for om enrichment in the oil shale layer in addition factors such as mixed deposition with clay minerals and detrital matter input cannot be ignored for their influence on om enrichment

geological controls on coal quality of the yili basin xinjiang northwest china abstract this study summarizes the results of geological petrographical geochemical and mineralogical analyses performed to determine the geological controls on coal quality of the yili basin in xinjiang province northwest china forty eight coal samples were collected from boreholes q12zk01 and z40zk1 and piliqing and musixiang coal mines the difference in base subsidence rate between the coal bearing strata badaowan and the xishanyao formations determines these differences of depositional environments swamp groundwater table and degree of terrigenous supply these factors may further cause the difference in coal quality the vitrinite contents ash yields volatile matter yields total mineral contents and most element contents are higher in coals of the badaowan formation from the q12zk01 and the musixiang mine than those of the xishanyao formation from the piliqing mine and the z40zk1 the high volatile matter yields of the coals in the badaowan formation relative to those in the xishanyao formation may be due to higher content of vitrinite that contains more volatile matters in comparison with the average concentrations for chinese and worldwide coals the yili coals are enriched mainly in ca na mg mn co sr ba and w but the other elements are depleted in the yili coals elements including si al k li ti cr cu rb zr pb and some ree la ce pr nd sm are predominantly associated with aluminosilicate minerals iron mg and mn in the coals of the musixiang mine and z40zk1 are associated mainly with carbonate minerals sulfur co and ni in the musixiang mine coals and b in the coals of q12zk01 and the z40zk1 mainly show an organic affinity sodium in the musixiang mine coals may occur in the brines

antimony and arsenic anomalies in the coal seams from the gokler coalfield gediz turkey abstract the gokler coalfield in the western part of turkey mainly contains high sulphur 4 5 to 11 5 on a dry basis bituminous 0 5 to 0 95 rr coals of middle miocene age the gokler coals from buyuk kucuk and unnamed seams are in general characterised on a mineral matter free basis by higher amounts of macerals of the vitrinite group av 95 5 than liptinite av 2 5 and inertinite av 2 contents geochemical characterisation of 45 coal samples on a whole coal dry basis was achieved using an energy dispersive polarised x ray fluorescence edp xrf spectrometer the gokler coals proved to be anomalously enriched in sb 8 3 2347 ppm av 134 ppm and as 170 3854 ppm av 833 ppm in the samples in comparison with range values for most world coals sb and as are respectively associated with epigenetic stibnite and iron sulfides both of which formed in microfractures and micropores in the gokler coals stibnite occurs mainly as prismatic crystals and less radial crystals scanning electron microscopy sem shows that some stibnites are chemically pure while others contain minor fe epigenetic fe sulfides pyrite and marcasite typically include in addition to fe and s minor amounts of as and trace amounts of zn as and zn are below the sem detection levels in syngenetic framboidal pyrites epigenetic calcites in the samples consist mainly of mg and fe and trace amounts of sr all epigenetic minerals such as stibnite iron sulfides calcite and quartz indicated that the gokler coals were mainly effected by post miocene hydrothermal mineralisations

structural analysis of a ductile brittle precambrian shear zone in the sierra madre wyoming western extension of the cheyenne belt abstract existing plate tectonic models for the cheyenne belt a proterozoic suture at the southern margin of the archean wyoming craton are based largely on data from the medicine bow mountains southern wyoming this paper tests the hypothesis that a major structural and geochronological discontinuity in the sierra madre of southern wyoming is the western extension of the cheyenne belt the sierra madre shear zone consists of a cataclastic western segment and a mylonitic eastern segment that comprises several mylonite zones the eastern segment records early ductile thrusting ca 1750 ma and later dextral strike slip faulting as revealed by macrostructural microstructural and quartz fabric analysis structures associated with these events are kinematically compatible and coeval with structures within the suture zone in the medicine bow mountains the correlation of shear zones in the two ranges is supported further by lithologic similarity of distinctive rocks north of and within the shear zones and the presence of unusual quartz fabrics documenting c slip in synkinematic granites in both ranges isolated exposures of mylonite along the dominantly cataclastic western segment suggest that the mylonitic shear zone was formerly more extensive the western segment of the sierra madre shear zone is a single zone of intense cataclasis that truncated and dismembered the earlier ductile shear zone kinematic analysis within the cataclastic zone suggests that it formed during north directed thrusting east striking south dipping thrust faults and associated overturned to the north recumbent folds are developed in supracrustal rocks directly north of the cataclastic fault zone this spatial association of north vergent structures and their apparent kinematic compatibility suggests that they are genetically related two major northwest striking cataclastic dextral strike slip in the eastern sierra madre appear to merge with the cataclastic thrust fault these cataclastic faults are interpreted as parts of a north vergent thrust tear system that cut across the original suture zone as rocks in the upper plate of the thrust were transported to the north it is not known whether this deformational event occurred in response to continued post suture convergence to the south or if it represents a separate and distinct precambrian event the prominent bend in the sierra madre shear zone may be an oroclinal flexure produced as a consequence of northward translation along the cataclastic thrust system

geochemical and mineralogical characteristics of a power station feed coal eggborough england abstract chemical and mineralogical analyses are presented for a power station feed coal in the yorkshire coalfield u k the mineralogy of the whole coal consists of quartz kaolinite illite mixed layer clay chlorite pyrite and carbonates pyrite carbonates and some of the kaolinite are diagenetic in separated low density fractions of the coal both pyrite and kaolinite are concentrated relative to the detrital minerals compared with the high density fractions the detrital clay mineralogy of these low density fractions contains less chlorite and the mixed layer clay to illite ratio is higher which is consistent with a grain size control during sedimentation the major element analyses are comparable with mudrocks in the stratigraphic sequence but there is evidence of na 2 o enrichment related to connate brinnes and the fe 2 o 3 content shows significant enrichment particularly in the ashes of the low density fractions the dissolution of oxhydroxide grain coatings associated with detrital sediment in the coal and also in the adjacent strata are probable sources of the iron in the diagenetic pyrite there is evidence of iron mobility in the sedimentary sequence and introduction into the coal itself during diagenesis within the coal trace elements are also enriched on an ash basis relative to the mudrocks and their origin is also probably very similar to that of iron a noteworthy feature of the trace element enrichment is that the enrichment factors for a number of elements are comparable with those determined for marine black shales in the sequence this suggests a common origin for the elements during the diagenetic processes analysis of the coal density fractions after correcting for detrital mineralogy suggests pb cu ni zn and possibly mn are associated with pyrite and v sr ba zr and nb are either directly or indirectly associated with organic components possibly zr and nb originate from dispersed volcanic ash

trace metal pollution of soils in northern england data from a regional geochemical survey of topsoils n 818 in rural and peri urban areas over a single parent material coal measures are used to identify two types of trace metal pollution severe local contamination at 20 sites and widespread diffuse pollution in more densely populated areas median concentrations of several trace metals in topsoils were significantly higher in areas of high compared to low population density percentage increases in parenthesis as 31 cu 39 fe 7 mo 26 36 ni 29 pb 20 sn 40 and zn 11 four potential pathways of diffuse trace metal pollution are postulated coal ash dispersal atmospheric aerosols derived from coal combustion the historical spreading of sewage waste and those related to road vehicles the statistical analysis of geochemical data classified by local human population density can be an effective means of identifying the magnitude and extent of diffuse pollution and could help to establish natural background levels

use of laser ablation icp ms to determine trace element distributions in coals with special reference to v ge and al laser ablation icp ms has been used to produce element profiles from polished coal samples the elements analysed v ge ni cu zn sr and ba were those known to have an organic association with the addition of al and fe as controls on the clay and pyrite abundances the element profiles were compared with the petrography and a statistical analysis was also carried out sporinite was found to have low trace element concentrations inertinite higher concentrations of detrital elements and vitrinite higher concentrations of v ge and al the relationships between these elements are explored and all are thought to be present in the organic matter and not as minerals it is thought that these elements became concentrated during diagenesis with the possibility that some of the al could be residual the cu ni ratio in the pyrite is relatively constant suggesting constant ionic proportions during diagenesis and possibly a seawater source

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

structure and kinematic genesis of the quealy wrench duplex transpressional reactivation of the precambrian cheyenne belt in the laramie basin wyoming seismic and borehole data in the southern laramie basin of southeastern wyoming outline a fault bordered pop up structure that is central to the quealy wrench duplex and the site of the quealy dome oil field this contractional duplex formed at a restraining fault offset between two parallel laterally extensive northeast trending fault zones the south and north quealy faults spaced about 2 mi 3 2 km apart these parallel fault zones are interpreted as wrench straights equivalent to the floor and roof thrusts of a duplex in a fold and thrust belt but described in map view rather than in cross section the quealy wrench duplex is comprised of three east vergent basement involved thrust imbricates and a west vergent antithetic thrust detached in permian shales duplex thrusts strike at high angles to the bordering south and north quealy fault zones measurements based on interpretive piercing point evidence and fault parallel differential shortening indicate that net slip on the dominant south quealy fault zone is dextral oblique a component of dextral slip is also indicated on the north quealy fault zone the south quealy fault and north quealy overland fault trends can be traced southwesterly into the footwall of the north trending arlington basin boundary thrust and projected into the precambrian cheyenne belt of the medicine bow mountains in the hanging wall of the arlington thrust it is proposed that the quealy wrench duplex is a product of precambrian shear zone reactivation along the cheyenne belt under permian and laramide tertiary transpression

concentration and mode of occurrence of trace elements in marine oil shale from the bilong co area northern tibet china abstract the bilong co oil shale zone is located in the south qiangtang depression this zone together with the shengli river changshe mountain oil shale zone in the north qiangtang depression northern tibet plateau represents a potentially large marine oil shale resource in china with the aim of better understanding geochemistry of marine oil shale 18 samples from the bilong co area are studied and 56 elements in them are determined the contents of mo se cd cs as bi u rb pb th li sr and zn are enriched from 1 3 to 35 0 times as compared with the average concentration in the crust clarke values whereas the other elements are slightly higher lower than the respective clarke values compared to common australian oil shales the contents of ce co cs f ga hf nb nd pb pr rb sc sn th and zr in the bilong co oil shale samples exhibit relatively high levels whereas as br cd cr cu dy er eu ho lu mo ni se tb tm u v y yb and zn are relatively depleted however the distribution patterns of trace elements are quite similar indicating that trace element speciation in oil shale is governed by general processes rather than by individual geochemical mechanisms within one particular sample the elements in the bilong co oil shale may be classified into three groups of association according to their modes of occurrence i e groups a b and c group a si al k na ti zr sc th sn nb ga ta be hf cs li rb ash rees is strongly correlated with ash yield and mainly has an inorganic affinity group b cr w mg mn br f sr ba has weakly or negatively positive correlation coefficients with an exception of f with ash yield group c zn bi cd ca fe pb hg co cu ni p mo se u as v shows negative correlation coefficients with ash yield with an exception of bi and possibly has an organic affinity

san jacinto monument case history the san jacinto monument was built in 1936 to commemorate the 100 year anniversary of the victory of the texan army over the mexican army the victory at the battle of san jacinto followed the defeat at the battle of the alamo and secured the independence of texas as well as several other states along the mexican border the monument consists of a 176 5 m high column resting on a large square mat with each side 37 8 m the mat foundation was designed by raymond dawson who chose an average pressure of 223 8 kpa under the mat dawson had settlement points placed on the mat foundation together with benchmarks away from the monument the settlement of the monument has been recorded over the last 70 years and shows a total settlement to date of 0 329 m the settlement appears to be almost complete this remarkable case history is used to evaluate current practice of calculating consolidation settlement and a best approach is suggested for such structures other issues addressed include the depth of influence the time rate of settlement the elastic modulus approach and the ultimate bearing capacity

organic petrology of hat creek coal deposit no 1 british columbia abstract the upper eocene hat creek coal deposits of british columbia canada are one of the thickest lignite to subbituminous coal deposits of the world and comprise 350 550 m of coal samples of sedimentary organic material were taken from a 560 m interval of interbedded shale siltstone and carbonate that was penetrated by corehole 75 106 in the centre of the coal basin and the reflectances of huminite eu ulminite from coal and kerogen from the organic material were determined and petrographical analyses were made the coal deposit contains many leaf and resinite rich horizons and the reflectance of huminite in these horizons in lower than in corresponding horizons containing less liptinite when compared with huminite in adjacent coal beds the reflectance of huminite in shale is lower that in siltstone is similar and huminite associated with carbonate rocks has slightly higher reflectance values the petrological variation in the coal is mainly within the huminite group of macerals the coal at the top of the deposits is lignite r o 0 38 and becomes subbituminous c r o 0 50 at the base the inertinite content is very low indicating a low level of peat fire or oxidation the early stages of transformation of gelinite to macrinite are described the paleoenvironment appeared to be lacustrine as determined by organic petrological analysis of coals and interbedded sediments four major zones each containing many subzones were found paleoenvironments were similar for the a and c zones and also for the b and d zones

petrology and geochemistry of the high sulphur coals from the upper permian carbonate coal measures in the heshan coalfield southern china abstract the heshan coals with very high organic sulphur content are found in the upper permian marine carbonate successions heshan formation in the heshan coalfield central guangxi southern china the petrography mineralogy and geochemistry of coals and non coal partings from the suhe and lilan coal mines of the heshan coalfield have been investigated using proximate petrographic inductively coupled plasma mass spectrometry icp ms x ray fluorescence xrf x ray diffraction xrd and scanning electron microscopy with an energy dispersive x ray sem edx techniques the sulphur content in the coals with ash less than 50 ranges from 5 3 to 11 6 of which more than 90 is organic sulphur reflecting a strong marine water influence on the palaeomire the high vitrinite reflectance 1 89 2 18 romax indicates that the coals in the heshan coalfield are mainly low volatile bituminous coal microscopic observation has revealed that the coal is mainly composed of vitrinite and inertinite macerals with relatively low tpi and high gi values suggesting an unusual strongly alkaline palaeomire with high ph xrd analysis plus optical and scanning electron microscopy show that the minerals in these coals are mainly quartz calcite dolomite kaolinite illite and pyrite although marcasite strengite and feldspar as well as some oxidised weathering products such as gypsum are also present most trace elements in the heshan coals are enriched with respect to their world mean with mo u and w highly enriched more than 10 times their world means the trace elements are believed to be associated either with organic compounds mo and u or minerals such as aluminium iron silicates sc ge and bi aluminium silicates cs be th pb ga and ree iron phosphates zn rb and zr iron sulphides as cd cr cu ni tl and v and carbonates sr mn and w abnormally high organic sulphur content high ash yields relatively high gi values very low tpi values very high u contents and very low th u ratios suggest that the heshan coals accumulated in low lying marine influenced palaeomires developed on carbonate platforms many of these characteristics have also been recorded in the tertiary coals of the circum mediterranean coal basins where no marine influence is present the similarities are thought to be produced by strongly alkaline groundwater chemistry common to both environments

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

san jacinto monument new soil data and analysis including subsidence abstractthe san jacinto monument was built in 1936 to celebrate the 100 year anniversary of the battlefield victory that gave texas its freedom ray dawson was in charge of the foundation design and decided to instrument the foundation to monitor the settlement of the monument the settlement has been recorded since 1936 and provides a very valuable long term record this settlement and other geotechnical data were studied and reported by briaud and his co authors in 2007 that study was based on data available at the time which was primarily from a 61 m deep boring in 1953 in 2007 fugro and texas am they show reasonably good agreement with modern settlement techniques one of the issues possibly affecting the settlement readings is the subsidence of the ground surface which can reach 3 m in

selected elements in major minerals from bituminous coal as determined by inaa implications for removing environmentally sensitive elements from coal abstract the four most abundant minerals generally found in euramerican bituminous coals are quartz kaolinite illite and pyrite these four minerals were isolated by density separation and handpicking from bituminous coal samples collected in the ruhr basin germany and the appalachian basin u s a trace element concentrations of relatively pure 99 separates of major minerals from these coals were determined directly by using instrumental neutron activation analysis inaa as expected quartz contributes little to the trace element mass balance illite generally has higher trace element concentrations than kaolinite but for the concentrates analyzed in this study hf ta w th and u are in lower concentrations in illite than in kaolinite pyrite has higher concentrations of chalcophile elements e g as and se and is considerably lower in lithophile elements as compared to kaolinite and illite our study provides a direct and sensitive method of determining trace element relationships with minerals in coal mass balance calculations suggest that the trace element content of coal can be explained mainly by three major minerals pyrite kaolinite and illite this conclusion indicates that the size and textural relationships of these major coal minerals may be a more important consideration as to whether coal cleaning can effectively remove the most environmentally sensitive trace elements in coal than what trace minerals are present

evidence for an inverted metamorphic gradient associated with a precambrian suture southern wyoming an inverted metamorphic gradient associated with the northern mylonite zone of the cheyenne belt a deeply eroded precambrian suture in southern wyoming has been documented within metasedimentary rocks of the early proterozoic snowy pass supergroup metamorphic grade in the steeply dipping supracrustal sequence increases from the chlorite through the biotite garnet and staurolite zones both stratigraphically and structurally upward toward the northern mylonite zone a minimum temperature increase of approximately 100 c over a km wide zone is required for this transition parallelism of inverted isograds with the trace of the northern mylonite zone implies a genetic relationship between deformation associated with that zone and the inverted metamorphic gradient within the snowy pass supergroup field evidence together with microstructural and petrofabric analysis indicate northward thrusting of amphibolite grade rocks over rocks of the snowy pass supergroup along the northern mylonite zone mineral equilibria and garnet biotite geothermometry on synkinematic mineral assemblages within the snowy pass metasedimentary rocks indicate deformation at minimum temperatures of 480 c and pressures of 350 400 mpa 3 5 4 0 kbar this implies tectonic burial or upper plate thickness of 13 15 km the narrow character of metamorphic zonation and microtextures within the snowy pass supergroup which indicate late synkine matic growth of garnet and staurolite preclude rotation of pre existing isograds by folding as a mechanism for development of the inverted gradient conductive transport of heat from the upper into the lower plate across the originally low angle thrust is insufficient to produce the necessary temperatures in the lower plate shear heating is considered insufficient to produce the observed metamorphic transition unless high shear stresses are postulated up dip advection of metamorphic fluids is a feasible but unproven mechanism for heat transport the possibility that rapid uplift due to stacking of several thrust sheets may have played a role in preserving the inverted metamorphic gradient cannot be evaluated at present

enrichment of arsenic lead and antimony in balingian coal from sarawak malaysia modes of occurrence origin and partitioning behaviour during coal combustion abstract the concentrations of mineral forming elements and trace elements in coal and coal ashes from balingian coalfield sarawak malaysia were assayed and their modes of occurrence enrichment origin and partitioning behaviour during coal combustion were studied as well balingian coal is high in as cu pb sb th and zn of particular concern are as as high as 181 ppm pb 325 ppm and sb 96 ppm all of which are highly enriched in balingian coal relative to their respective coal clarke values arsenic pb and sb in the coal are mostly organic and to a lesser extent they are bound to discrete minerals in the form of aluminosilicates during coal combustion in the power plant a substantial portion of organically associated as pb and sb in the coal vaporize and are released into the atmosphere whereas ba and mn are highly enriched in the coal ashes as compared to the raw coal the as pb and sb anomalies observed in balingian coal may be related to a large sb as and probably pb mineralization in the vicinity of the coalfield with some localised epigenetic infiltration of these elements from the surrounding rocks by circulating groundwaters

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

petrographic and geochemical contrasts and environmentally significant trace elements in marine influenced coal seams yanzhou mining area china abstract the yanzhou mining area in west shandong province china contains coals of permian and carboniferous age the 31 and 32 seams of the permian shanxi formation and seams 6 15 17 of the carboniferous taiyuan formation were analyzed for coal petrology mineralogy and geochemical parameters the parameters indicate that the coal is high volatile bituminous in rank the coal is characterized by high vitrinite and low to medium inertinite and liptinite contents these properties may be related to evolution of the coal forming environment from more reducing conditions in a marine influenced lower delta plain environment for the early taiyuan coals to more oxidizing paleoenvironments in an upper delta plain for the upper shanxi coal seams the major mineral phases present in the coal are quartz kaolinite pyrite and calcite sulfur is one of the hazardous elements in coal the major forms of sulfur in coal are pyritic organic and sulfate sulfur pyritic and organic sulfur generally account for the bulk of the sulfur in coal elemental sulfur also occurs in coal but only in trace to minor amounts in this paper the distribution and concentration of sulfur in the yanzhou mining district are analyzed and the forms of sulfur are studied the sulfur content of the taiyuan coal seams is considerably higher than that of the shanxi coals organic sulfur content is positively correlated to total and pyritic sulfur the vertical variation of cu zn pb as th u and sulfur contents in coal seam 3 of the shanxi formation in the xinglongzhuang mine show that all these trace elements with the exception of th are enriched in the top and bottom plies of the seam and that their concentrations are also relatively high in the dirt bands within the seam the pyritic sulfur is positively correlated with total sulfur and both are enriched in the top bottom and parting plies of the seam the concentrations of the trace elements are closely related to sulfur and ash contents most of the trace elements are correlated with the ash content and may be associated with the mineral matter in the coal

reanalysis long term settlement of san jacinto monument with a power law model the settlement of san jacinto monument is a very valuable long term monitoring data over 80 years for studying time dependent behavior in geotechnical engineering because the large discrepancy between predicted data and measured data in previous publications with other methods applied it is restudied with a power law model by the author the concept of creep associated with rate of loading is introduced to verify the viewpoint two kinds of tests i e 1d consolidation test and 1d compression test on the clay from national geotechnical experimental site nges at texas a m university are conducted the case of san jacinto monument is reanalyzed with the model and the predicted data by the model are in very good agreement with the actual data which demonstrate that the proposed model is suitable and flexible for two types of time dependent behavior namely consolidation and creep in geotechnical engineering

on the origin of a phosphate enriched interval in the chattanooga shale upper devonian of tennessee a combined sedimentologic petrographic and geochemical study abstract the devonian chattanooga shale contains an uppermost black shale interval with dispersed phosphate nodules this interval extends from tennessee to correlative strata in kentucky indiana and ohio and represents a significant period of marine phosphate fixation during the late devonian of north america it overlies black shales that lack phosphate nodules but otherwise look very similar in outcrop the purpose of this study is to examine what sets these two shales apart and what this difference tells us about the sedimentary history of the uppermost chattanooga shale in thin section the lower black shales pbs show pyrite enriched laminae and compositional banding the overlying phosphatic black shales phbs are characterized by phosbioclasts have a general banded to homogenized texture with reworked layers and show well defined horizons of phosphate nodules that are reworked and transported in the phbs up to 8000 particles of p debris per cm2 occur in reworked beds whereas the background black shale shows between 37 88 particles per cm2 in the pbs the shale matrix contains between 8 16 phosphatic particles per cm2 the shale matrix in the phbs contains 5 6 inertinite whereas just 1 inertinite occurs in the pbs the shale matrix in both units is characterized by flat ree patterns shale normalized whereas phosbioclast rich layers in the phbs show high concentrations of rees and enrichment of mrees negative ce anomalies are common to all samples but are best developed in association with phosbioclasts redox sensitive elements co u mo are more strongly enriched in the pbs when compared to the phbs trace elements associated with organic matter cu zn cd ni show an inverse trend of enrichment deposited atop a sequence boundary that separates the two shale units the phbs unit represents a transgressive systems tract and probably was deposited in shallower water than the underlying pbs interval the higher phosphate content in the phbs is interpreted as the result of a combination of lower sedimentation rates with reworking winnowing episodes three types of phosphatic beds that reflect different degrees of reworking intensity are observed strong negative ce anomalies and abundant secondary marcasite formation in the phbs suggests improved aeration of the water column and improved downward diffusion of oxygen into the sediment the associated oxidation of previously formed pyrite resulted in a lowering of pore water ph and forced dissolution of biogenic phosphate phosphate dissolution was followed by formation of secondary marcasite and phosphate repeated episodic reworking caused repetitive cycles of phosphatic dissolution and reprecipitation enriching mrees in reprecipitated apatite a generally deeper seated redox boundary favored p remineralization within the sediment matrix and multiple repeats of this process in combination with wave and current reworking at the seabed led to the formation of larger phosphatic aggregates and concentration of phosphate nodules in discrete horizons

wilson creek field u s a piceance basin northern colorado field classification basin piceance creek basin type foredeep reservoir rock type sandstone and limestone reservoir environment of deposition eolian shoreline and shallow marine reservoir age jurassic and pennsylvanian petroleum type oil gas and condensate trap type thrusted anticline

comparison of elemental distribution in fresh and weathered samples of selected coals in the jurassic cretaceous kootenay group british columbia canada abstract the concentration of 52 elements in a suite of fresh coal seams and their weathered outcrops was determined using inaa the concentration of organically bound elements such as br cl and s in samples from weathered outcrops was lower than their fresh samples in contrast the concentration of inorganically bound elements such as al ga and fe in fresh samples was lower than their weathered outcrops the concentration or depletion of elements with intermediate bonding such as s in weathered samples was dependent on its affinity towards the organic or inorganic fraction of coal

paleomagnetism of the middle proterozoic laramie anorthosite complex and sherman granite southern laramie range wyoming and colorado we present the results of a combined paleomagnetic and 40ar 39ar geochronologic investigation of the middle proterozoic laramie anorthosite complex and sherman granite in the southern laramie range of wyoming and colorado anorthosites and monzosyenites of the laramie anorthosite complex yield a well defined characteristic magnetization of northeast declination d and moderate negative inclination i although antipodal normal and reverse polarity magnetizations are present at three sites a grand mean direction from 29 of 35 sites in the complex is d 44 6 i 48 7 k 77 4 95 3 1 alternating field af and thermal demagnetization behavior and rock magnetic experiments indicate that magnetization is carried by low ti titanomagnetite of single or pseudo single domain character that occurs as elongate to rod shaped inclusions in plagioclase and potassium feldspar the sherman granite contains a dual polarity magnetization that is less well defined than that of the laramie anorthosite complex but similar in declination and inclination d 53 1 i 48 1 k 46 5 95 7 6 n 8 14 sites rock magnetic data indicate the primary carrier of remanence in sherman granite is magnetite the 40ar 39ar geochronologic data from sherman granite hornblende biotite and microcline indicate that subsolidus cooling was moderate to relatively rapid through the range of temperatures over which magnetization was blocked and that the age of remanence is about 1415 ma microcline data indicate that the laramie anorthosite complex and sherman granite have probably not been thermally remagnetized paleomagnetic poles from the laramie anorthosite complex and sherman granite are indistinguishable at the 95 confidence level and individual virtual geomagnetic poles vgps from both units are combined to provide a mean pole at 215 0 e 6 7 s k 46 9 a95 3 5 n 37 vgps the location of this pole is similar to paleomagnetic poles derived from 1480 ma to 1450 ma intrusions elsewhere in north america but it plots significantly north of those from middle proterozoic sedimentary strata of the belt supergroup and sibley group in addition to the characteristic magnetization samples from some sites in sherman granite contain a remanence of southeast declination and shallow negative inclination d 154 9 i 16 0 k 90 6 95 9 7 n 4 sites this secondary magnetization was probably acquired during late paleozoic time

the ratio of tellurium and selenium in geological material as a possible paleo redox proxy abstract only few data for both tellurium and selenium in different geological materials including international reference materials have been available so far in this study the te se ratio has been investigated in more detail to provide a better understanding of the correlation of these two elements in the geological environment nine international reference materials irms and 79 different geological samples spanning a wide range of formation times and conditions from the paleoproterozoic to present were analyzed with quadrupole dynamic reaction cell drc icp ms these samples include basalts shales river and beach sediments loess dolomites a recent cold water coral precambrian manganese and iron formations and cenozoic marine ferromanganese nodules and crusts a wide range of concentrations between 0 01 and 1 5 g g for se and 0 01 and 90 g g for te was measured and the most interesting feature was found to be the te se ratio in the different geological matrices while most rock and sediment samples fall within the range of te se ratios typical of the average earth s crust a significant enrichment of te over se is evident for modern marine mn fe oxide precipitates with the most pronounced te enrichment found for hydrogenetic ferromanganese crusts which form under fully oxidizing conditions the apparent positive trend of the degree of te se fractionation with the redox potential of the formation environment suggests that the te se ratio may represent a potential paleo proxy for redox environments

chalcophile elements in western canadian coals abstract concentrations of chalcophile elements as co cu hg mo ni pb sb and zn in western canadian coals were determined using inaa and aas the concentrations of these elements in western canadian coals are within the range for most world coals however there are some high values for coals from outcrops and from areas which are not currently being mined arsenic content in the majority of western canadian coals particularly those currently being mined is low 0 2 3 ppm however there are coals with high arsenic content for example lignites from hat creek a zone contain between 4 0 and 14 0 ppm as in some samples from comox and suquash the as concentration is as high as 240 ppm and 1400 ppm respectively the enrichment of as in high arsenic coals is related to the geology and nature of country rocks associated with the coal seams the concentration of other elements for most western canadian coals particularly those being mined are within the range for most world coals in these coals the concentration ranges in ppm of chalcophile elements are 0 3 3 6 for sb 0 8 4 6 for co 7 35 for cu

rare earth elements in a sampled coal from the pirin deposit bulgaria abstract rare earth elements la ce sm eu tb yb and lu in a columnar section of the coal of the pirin deposit bulgaria have been determined by neutron activation analyses the ree content in the coals is lower than the average ree content of shales from north america europe and the soviet union the ree abundances increase with the increasing ash content of the coals the bottom of the seam is slightly enriched in ree the trend being more pronounced in hree tb yb lu the ree content depends on the thickness of the coal layers the thin coal layers are enriched in ree as compared to the thick ones the chondrite normalized distribution patterns are very uniform they are characterized by a negative eu anomaly whose mean value is 0 30 varying in the individual samples from 0 21 to 0 49 and a positive lu anomaly it is supposed that the eu anomaly is inherited from the source rocks the shale normalized distribution patterns show a distinct relative enrichment in hree and a negative eu anomaly the relative enrichment in hree is a specific feature of the ree geochemistry in the pirin deposit the lree hree ratio is lower than that of composite shale it increases with the increasing ash content of the coals and from the bottom to the top of the coal bed ree are bound predominantly to the aluminosilicates of the mineral matter in the coals all ree are positively correlated to the ash si al fe and na the source of ree in coals is mainly the suspended terrigenous material the specific enrichment of ree in the ash of low ash coals is a result of the interaction between the dissolved ree and the products of disintegration and decay of organic substances mainly the humic acids

geochemistry of trace elements in can coal miocene canakkale turkey abstract this study focuses on the geochemistry of trace elements and the coal quality parameters of miocene lignite s from can basin twelve coal samples have been studied using proximate and ultimate analyses x ray powder diffraction inductively coupled plasma mass spectrometry inductively coupled plasma atomic emission spectrometry scanning electron microscopy with energy dispersive x ray microanalysis and organic petrographic analyses the can coals on an air dried basis are characterized by broad variation of ash ranging from 4 42 to 36 72 high total sulphur contents up to 8 10 and high gross calorific values 3870 6612 kcal kg the mineral matter of the studied coal samples is made up of quartz pyrite clay minerals and gypsum major elements correlate positively with dry ash contents demonstrating an association with inorganic constituents for twenty trace elements including as b ba be cd cu co f hg mo ni pb sb se sn th tl u v and zn received much attention due to environmental and human health concerns based on statistical analyses most of the trace elements except for ba mo se and u show an affinity to ash content elements including as cu co and hg appear to be associated with pyrite the concentrations of the trace elements are within the range of world coal average however the v content is higher than the world coal value and some volatile elements such as as b and u are slightly enriched in some coal samples

kinematic history of the cheyenne belt medicine bow mountains southeastern wyoming the proterozoic cheyenne belt marks the southern boundary of the archean wyoming province within the medicine bow mountains it consists of strongly deformed lithologically distinct blocks bounded by mylonite zones detailed field and petrographic investigations of the boundary augmented by study of microscopic kinematic indicators allow us to refine existing models for tectonic development of the belt northward thrusting under amphibolite facies conditions along low angle mylonite zones emplaced successively deeper crustal blocks over supracrustal rocks of the wyoming province mylonite zones were subsequently steepened and reactivated under greenschist facies conditions during a period of distributive dextral strike slip we suggest oblique convergence between an island arc and the wyoming craton as a possible mechanism for both deformational events accretionary events in eastern and western north america which involved initial convergence followed by strike slip provide a phanerozoic analog for our model

geochemistry of two cretaceous coal bearing sequences james bay lowlands northern ontario and peace river basin northeast british columbia cretaceous coal bearing sequences from the moose river basin in northern ontario and the peace river basin in northeast british columbia were analysed for trace and major element contents modes of occurrence of the trace elements are proposed on the basis of pearson correlation coefficients and scanning electron microscopy coupled with energy dispersive x ray analysis the moose river basin lignite was deposited in an alluvial floodplain environment and the restricted mineralogy dominated by quartz and kaolinite reflects derivation from a highly weathered terrain the bituminous coal from the peace river basin was deposited in an alluvial to deltaic environment with a dominant mineralogy including quartz illite kaolinite mixed layer clays carbonates barite feldspar and pyrite trace element contents in both deposits are comparable to the average concentration in united states coals modes of occurrence of trace elements in the coals are extremely variable and depend on local conditions both dur

seismic reflection profiling of the cheyenne belt proterozoic suture in the medicine bow mountains southeastern wyoming a tie to geology the cheyenne belt a broad mylonitic shear zone marks a 1 8 1 7 ga suture between archean craton to the north and a proterozoic island arc to the south a university of wyoming seismic reflection profile across the medicine bow mountains imaged the steeply dipping cheyenne belt and crosscutting laramide faults by combining surface geology with reflection data from a line that trended oblique to the cheyenne belt suture and laramide thrusts the true subsurface geometry of both could be resolved the suture zone dips 60 southeast to depths of at least 9 to 14 km a 5 to 10 km thick zone of reflectors project to the surface near mapped laramide faults and have a true structural dip of 45 the imbricate thrusts within this zone cut the cheyenne belt near 9 km depth some weaker events persist throughout the archean lower crust however no clear moho is observed the subsurface geometry of the cheyenne belt suggests that archean crust is not absent at depth just south of the southernmost splay of the suture as nd isotope studies might suggest alternatively the proterozoic hanging wall thickens such that rising plutons may form completely within the hanging wall and show only proterozoic geochemical signatures the complex reflectivity pattern observed in the cheyenne belt line is caused mainly by the multideformational history of the area and the oblique orientation of the line ties between reflections and outcrop show that fault related lithologic contrasts and deformation within the fault zones generated reflectors at midcrustal depths during the proterozoic later laramide brittle faulting add to rather than erased the reflectivity

sand body orientation palaeoslope analysis and basin fill implications in the westphalian a c of great britain channel orientation and palaeoflow analyses across the british westphalian carboniferous coalfields show that three main inflow directions dominated the palaeogeography from the mid langsettian to the mid bolsovian in eastern scotland and ne england flow was mainly from the n and ne in the pennine basin of north central england flow was mainly from the w and nw whilst in south wales main flow from the sw was compatible with a westerly system that also branched to give the northerly inflows recorded in the culm basin of southwest england the depositional area included discrete tectonic depocentres notably the pennine basin which was traversed directly and tangentially by major channel belts these basins were essentially incidental to the main channel pathways but sand body characteristics vary according to basin location a new depositional model for the post rift pennine basin is proposed relating sand concentrations and connectivities to the depositional and tectonic setting the description of dominant sw to ne flow across south wales through much of the langsettian and duckmantian in contrast to the centripetal inflows previously proposed implies some similar channel depocentre relationships to those described here for the pennine basin

uranium thorium systematics of two canadian coals abstract a detailed study of u th distribution in two lower cretaceous coals in canada shows that for these coals formed in a continental fluvial and deltaic environment with no marine influence the u contents are in the range 0 07 7 5 ppm with th in the range 0 3 11 0 ppm average th u ratios are near 2 which indicates slight uranium enrichment the environments of the two coals show different degrees of weathering montmorillonite illite and kaolin gibbsite and u values are lowest in the more weathered environment in sedimentary profiles associated with the coals the maximum uranium values are not in the coals but in carbonaceoss clay sediments above and below coal seams uranium distribution patterns can be correlated cith ni cu rb pb sr and zr indicating contributions from heavy minerals plus more mobile species possibly simple organic compounds which are adsorbed or bonded onto claysor organic matter

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

high selenium in the carboniferous coal measures of northumberland north east england the carboniferous lower and middle coal measures coals of the northumberland coalfield are anomalously rich in selenium se content up to 62 ppm compared to the averages for the common uk and worldwide coals as well as posing an environmental toxicity threat se is now regarded as an important resource for alloys photovoltaic products and nanotechnologies and high se coals in north east england offer an opportunity to assess the se means of occurrence origins transport mechanisms and enrichment in coals at least two generations of pyrite host high se in the sampled coal seams microbial formed disseminated pyrite both cubic and framboidal in habit and later cleat filling pyrite identified by petrographic observations laser ablation methods and sulphur isotope compositions there is a notable se enrichment of up to 250 ppm in later formed cleat filling pyrite trace element enrichment may have been sourced and influenced by seawater distribution during diagenesis and localised dykes and deformation may have acted as an enrichment mechanism for sampled seams in the region the high se coals in northumberland may provide a potential e tech element source and should be considered and carefully managed as coal mining and production are reduced in the area the study also highlights the nature of se enrichment in pyritic coals affected by cleat formation and multiple episodes of mineralisation important as critical element demand continues to increase worldwide

in situ and laboratory stress strain relationships the question of whether or not the end of primary consolidation curve from laboratory oedometer tests is representative of in situ behaviour has been the subject of much discussion the behaviour of the berthierville test embankment is described and in situ effective stress strain curves are defined for two well defined clay sublayers these compressibility curves are then compared with laboratory end of primary consolidation curves similar comparisons are also made for sublayers under three other well instrumented embankments all the results show that the laboratory end of primary consolidation curve strongly underestimates in situ settlements and thus that theory a is not valid on s est souvent demande si la courbe de la fin de consolidation primaire obtenue a partir d essais oedometriques en laboratoire represente effec tivement le comportement en place l article decrit le comportement du remblai experimental de berthierville et definit les courbes contrainte deformation effectives en place pour de

concentration of elements in lacustrine coals from zone a hat creek deposit no 1 british columbia canada abstract coal samples from the 170 m thick a zone of the hat creek coal deposit no 1 in central british columbia were examined for major minor and trace element distribution the coal is lignite subbituminous in rank and of eocene age this study shows 1 as b br cl and s are the only elements organically associated in these samples 2 concentration of certain elements such as fe mn and co can be related to the presence or absence of carbonate and or sulphide minerals 3 distribution of certain elements i e al b br cl cr fe th u and zn follow similar patterns of concentration or depletion across the vertical thickness of zone a and suggest three depositional cycles 4 concentration of boron versus chromium sodium sulphur and uranium for these coals clearly placed them in a freshwater environment 5 rates of sedimentation using the na k ratio also suggest three depositional cycles 6 in resinite samples hand picked from these coals the concentrations of all elements except as and se were lower than their concentrations in the whole coals

clays and other minerals in coal seams of the moura baralaba area bowen basin australia abstract the clays and other minerals in a succession of late permian coals of high volatile bituminous to semi anthracite rank have been identified using low temperature oxygen plasma ashing and x ray diffraction and evaluated to identify the relative roles in mineral matter formation of detrital input early diagenesis in the peat swamp and late diagenesis associated with rank advance although well ordered kaolinite of probable early diagenetic origin is abundant throughout the succession the uppermost and lowermost seams of the sequence regardless of rank contain relatively abundant illite and or interstratified illite smectite along with a small but significant proportion of chlorite these clays are thought to be essentially of detrital origin washed or blown into the peat deposit in relative abundance during the establishment and subsequent overwhelming of an extensive and long lived swampy environment quartz is also abundant in the lower seams of the sequence especially close to the regional sediment source area illite is unusually abundant in the topmost seam in both high and low rank parts of the succession and thus appears to represent detrital input from a particular source material although significant changes are reported in the clays of the associated strata due to rank advance the principal effect of rank advance on the minerals in the coal itself appears to be the development of an ammonium illite and possibly some additional fine grained chlorite in the semi anthracite material isolation within the organic matter of the coal is thought to have inhibited access for ions such as k which might otherwise have become involved in metamorphic reactions and given rise to mineralogical changes commonly found in non coal sedimentary successions

elemental distribution in coal seams at the fording coal mine british columbia canada abstract elemental compositions of coals from fording southeastern british columbia were examined using inaa and icp spectrometry detailed elemental analyses were carried out for coal seams in two equivalent sections and also within selected coal seams elemental concentrations in coal bands within individual seams were compared with those of tonstein bands and other partings within coal seams there was an overall decrease in the concentration of al as lu sc and th for coal bands within a coal seam in contrast the concentration of these elements in partings in the same seam remained almost constant or increased from roof to floor concentrations of certain elements for example k mg mn na sb th u v and zn for coal samples occurring in the eagle mountain section follow similar trends regular variation in the concentration or depletion of some elements indicates the presence of three cycles at eagle mountain and two cycles in the greenhills section a good correlation was observed between b concentration and the environment of deposition of these coals particularly when the b contents of coals deposited in fresh water and a brackish environment are compared the coals in the eagle mountain section were deposited in a semi brackish environment with the exception of the four uppermost coal samples which were deposited in a freshwater to semi brackish environment correlations between b and s or b and the br cl ratio were clearly grouped according to the depositional environment of the coals concentration of cr was greater for coals deposited in fresh water in contrast the th was more abundant in brackish coals

petrology mineralogy and geochemistry of mined coals western venezuela upper paleocene to middle miocene coal samples collected from active mines in the western venezuelan states of tachira merida and zulia have been characterized through an integrated geochemical mineralogical and petrographic investigation proximate ultimate calorific and forms of sulfur values major and trace element vitrinite reflectance maceral concentrations and mineral matter content have been determined for 16 channel samples from 14 mines ash yield generally is low ranging from b 1 to 17 wt mean 5 wt on a dry basis db total sulfur content is low to moderate ranging from 1 to 6 wt db average 1 7 wt calorific value ranges from 25 21 to 37 21 mj kg 10 840 16 000 btu lb on a moist mineral matter free basis average 33 25 mj kg 14 300 btu lb placing most of the coal samples in the apparent rank classification of high volatile bituminous most of the coal samples exhibit favorable characteristics on the various indices developed to predict combustion and coking behavior and concentrations of possible environmentally sensitive elements as be cd cr co hg mn ni pb sb se th and u generally are similar to the concentrations of these elements in most coals of the world with one or two exceptions concentrations of the liptinite maceral group range from b 1 to 70 vol five samples contain n 20 vol liptinite dominated by the macerals bituminite and sporinite collotelinite dominates the vitrinite group telinite was observed in quantities of v1 vol despite efforts to better quantify this maceral by etching the sample pellets in potassium permanganate and also by exposure in an oxygen plasma chamber inertinite group macerals typically represent b 10 vol of the coal samples and the highest concentrations of inertinite macerals are found in distantly spaced n 400 km upper paleocene coal samples from opposite sides of lago de maracaibo possibly indicating tectonic controls on subsidence related to construction of the andean orogen values of maximum reflectance of vitrinite in oil ro max range between 0 42 and 0 85 and generally are consistent with the high volatile bituminous rank classification obtained through astm methods x ray diffraction analyses of low temperature ash residues indicate that kaolinite quartz illite and pyrite dominate the inorganic fraction of most samples plagioclase potassium feldspar calcite siderite ankerite marcasite rutile anatase and apatite are present in minor or trace concentrations semiquantitative values of volume percent pyrite content show a strong correlation with pyritic sulfur and some sulfide hosted trace element concentrations as and hg this work provides a modern quality dataset for the western