geochemical and mineralogical evidence for a coal hosted uranium deposit in the yili basin xinjiang northwestern china abstract the petrological geochemical and mineralogical compositions of the coal hosted jurassic uranium ore deposit in the yili basin of xinjiang province northwestern china were investigated using optical microscopy and field emission scanning electron microscopy in conjunction with an energy dispersive x ray spectrometer as well as x ray powder diffraction x ray fluorescence and inductively coupled plasma mass spectrometry the yili coal is of high volatile c b bituminous rank 0 51 0 59 vitrinite reflectance and has a medium sulfur content 1 32 on average fusinite and semifusinite generally dominate the maceral assemblage which exhibits forms suggesting fire driven formation of those macerals together with forms suggesting degradation of wood followed by burning the yili coals are characterized by high concentrations of u up to 7207 g g se up to 253 g g mo 1248 g g and re up to 34 g g as well as as up to 234 g g and hg up to 3858 ng g relative to the upper continental crust the rare earth elements rees in the coals are characterized by heavy or and medium ree enrichment the minerals in the yili coals are mainly quartz kaolinite illite and illite smectite as well as to a lesser extent k feldspar chlorite pyrite and trace amounts of calcite dolomite amphibole millerite chalcopyrite cattierite siegenite ferroselite krutaite eskebornite pitchblende coffinite silicorhabdophane and zircon the enrichment and modes of occurrence of the trace elements and also of the minerals in the coal are attributed to derivation from a sediment source region of felsic and intermediate petrological composition and to two different later stage solutions a u se mo re rich infiltrational and a hg as rich exfiltrational volcanogenic solution the main elements with high enrichment factors u se as and hg overall exhibit a mixed organic inorganic affinity the uranium minerals pitchblende and coffinite occur as cavity fillings in structured inertinite macerals selenium as and hg in high pyrite samples mainly show a sulfide affinity

nature of laminations and mineralization in rhinoceros enamel using histology and x ray synchrotron microtomography potential implications for palaeoenvironmental isotopic studies abstract incremental features of rhinoceros molar enamel were studied quantitatively on histological slices the different kinds of incremental features of enamel were related to one another and counted to determine the rate and duration of crown formation and to clarify the status of the laminations the mineralization and the microstructure of the enamel were examined in a rhinoceros molar germ using x ray synchrotron microtomography respectively using absorption and phase contrast mode at different levels of resolution from 45 71 m for the largest scale up to 0 28 m for the finest one the different microtomographic data were combined to obtain a multiscale integrated overview of the microstructure and mineralization in order to understand better the relationship between these two aspects additional human and herbivorous mammal teeth were examined qualitatively using histological sectioning to obtain a better understanding of laminations in mammal tooth enamel laminations regularly spaced features parallel to the retzius lines represent regular isochrons of enamel deposition this study shows that laminations and cross striations are equivalent daily features in enamel of rhinoceros humans and probably of middle sized and large herbivorous mammals in general laminations are shown to be three dimensional alignments of cross striations in addition to the fact that cross striations are visible only in prismatic enamel observation of histological slices and high resolution phase contrast x ray synchrotron microtomography demonstrate three main parameters influencing the dominant aspect of daily features in rhinoceros and human enamel the angle between prisms and retzius lines the enamel deposition rate and the thickness of the histological slices given their daily nature laminations can be used to determine the crown formation time of middle sized and big herbivorous mammals quantitative study of the enamel mineralization in the rhinoceros germ fragment using x ray synchrotron microtomography suggests that the innermost 20 m of the enamel near the enamel dentin junction are highly mineralised 77 90 of the final enamel mineralization during or just after the deposition of the corresponding enamel matrix integrated microtomographic study shows that this area corresponds to the thin aprismatic enamel layer at the edj level plus a thin layer of radial enamel directly adjacent it appears that in some parts of the enamel there may be a considerable time lag between matrix deposition and full maturation which could have important implications for geochemical studies this study reinforces the previously suggested hypothesis that isotopic measurements derived from the innermost enamel may represent the period most closely related to matrix secretion by using information derived from incremental features laminations and retzius lines and restricting the isotopic measurements to the innermost part of the enamel precise temporal calibration of isotopic signals should be possible and the complication of time averaging due to enamel maturation could be avoided or strongly reduced

isotopic analysis of tooth enamel carbonate from modern north american feral horses implications for paleoenvironmental reconstructions the accuracy of paleoenvironmental reconstructions based on isotope analyses of equid teeth is currently uncertain because the exact relationship between the isotope composition of modern feral equids and their environment has not been thoroughly studied we analyzed the carbon and oxygen isotope values 13c and 18o of tooth enamel carbonate and the 13c values of fecal samples from modern feral horses we compared those values with the 13c values of local vegetation and the 18o values of local waters herds were studied in two contrasting localities eastern oregon where grasslands consisted of 100 c3 species and new mexico where 95 of the grasses were c4 species carbon isotope analyses of fecal material and tooth enamel suggest that horses consumed primarily grass but some new mexico horses also consumed significant amounts of shrubs and or forbs microhistological analyses of fecal samples show that oregon horses consumed 95 grass and oregon enamel 13c values are consistent with a diet containing 100 c3 plants microhistological analyses of fecal samples from new mexico indicate a diet averaging 75 grass while enamel 13c values suggest that diets averaged 85 c4 plants range 72 97 thus reconstructions of the c3 c4 ratio of grasses in ancient grasslands that are based on the 13c values of fossil equid teeth may underestimate the abundance of c4 grasses the mean 18o values of tooth enamel paralleled the trends observed in the mean 18o values of precipitation however the mean 18o values of enamel carbonate from oregon and new mexico differed by only 3 3 which is less than the difference in the mean 18o values of precipitation 6 5 in addition the range of 18o values within new mexico enamel samples 6 5 was greater than the difference between mean enamel 18o values at each site calculated values for the 18o of water ingested by horses are 2 3 more positive than mean 18o values for corresponding precipitation suggesting that horses consumed waters that were enriched in 18o due to evaporation while our results confirm that local climatic and hydrological conditions can influence the 18o values of equid enamel they also show that the 18o values of equid teeth are not always a direct proxy for the isotope ratios of precipitation

testing the ability of surface arrays to monitor microseismic activity recently there has been much interest in the use of data from surface arrays in conjunction with migration based processing methods for passive seismic monitoring in this study we use an example of this kind of data recorded whilst 18 perforation shots with a variety of positions and propellant amounts were detonated in the subsurface as the perforation shots provide signals with known source positions and origin times the analysis of these data is an invaluable opportunity to test the accuracy and ability of surface arrays to detect and locate seismic sources in the subsurface in all but one case the signals from the perforation shots are not visible in the raw or preprocessed data however clear source images are produced for 12 of the perforation shots showing that arrays of surface sensors are capable of imaging microseismic events even when the signals are not visible in individual traces we find that point source locations are within typically 45 m laterally of the true shot location however the depths are less well constrained 150 m we test the sensitivity of our imaging method to the signal to noise ratio in the data using signals embedded in realistic noise we find that the position of the imaged shot location is quite insensitive to the level of added noise the primary effect of increased noise being to defocus the source image given the migration approach the array geometry and the nature of coherent noise during the experiment signals embedded in noise with ratios 0 1 can be used to successfully image events furthermore comparison of results from data and synthetic signals embedded in noise shows that in this case prestack corrections of traveltimes to account for near surface structure will not enhance event detectability although the perforation shots have a largely isotropic radiation pattern the results presented here show the potential for the use of surface sensors in microseismic monitoring as a viable alternative to classical downhole methods

oxygen isotopic composition of fossil horse tooth phosphate as a record of continental paleoclimate abstract oxygen isotopic elemental and x ray data are presented for a suite of 24 fossil horse teeth from nebraska ranging in age from 18 2 to 8 5 ma to test the use of 18o of enamel phosphate 18op04 as a quantitative record of continental climate modern equid teeth were analyzed to estimate a relationship between 8op04 and environment water multiple samples of seven different fossil species from burge quarry a 12 ma attritional fossil deposit indicate the diagenetic overprints exist but can be detected by decreased p concentration and increased crystallinity relative to modern enamel isotopic variation for the pristine samples from burge quarry is 1 5 1 n 9 which may represent the resolution of the procedure within a stratigraphic horizon there are no apparent correlations with body size hypsodonty or phylogeny a range of 7 0 in 18op04 occurs over the 10 m y interval a trend towards depleted 18op04 of about 4 corresponds to a depletion of up to 6 0 in 18o of precipitation between 18 2 and 8 5 ma but the range of variation of burge is large relative to the climate signal our results demonstrate that 18op04 should be useful in quantitatively reconstructing cenozoic continental paleoclimate on 106 year timescales isotopic variation due to taphonomic bias and the terrestrial rock record will likely obscure higher order climate signals

intra tooth isotope variations in late miocene bovid enamel from afghanistan paleobiological taphonomic and climatic implications abstract the rich mid turolian site of molayan afghanistan has yielded more than 100 mandibles from the bovid tragoportax afghanicus in this study we document different aspects of the paleobiology and paleoecology of this fossil bovid by examining patterns of inter and intra tooth carbon and oxygen isotopic analyses in m1 to m3 molars from five specimens accurate paleoecological and paleoclimatic inferences based on carbon and oxygen isotope analyses in fossil enamel are directly dependent upon the way in which teeth are sampled as well as taphonomic processes which are responsible for fossil accumulation because this sampling methodology provides a unique opportunity to detect seasonal changes in diet and environment during tooth formation it also offers the possibility of testing between catastrophic and progressive deposition at this site preservation of 13c and 18o values is shown to be good and permits inter individual comparisons of isotopic trends to be made timing of molar crown formation and enamel growth rate were deduced from the pattern of intra tooth carbon and oxygen isotope variation the pattern of 18o variation found in the first and second molars is similar in all the individuals which suggests that a single birth season occurred probably before the hot dry season large differences in average 18o values 2 5 are found within a single cohort and indicate that fossil accumulation was progressive rather than catastrophic the hypothesis that t afghanicus evolved in an open environment is supported by high 13c values in a c3 context increasing temperature and or aridity eastward along the greco irano afghan biogeographic province is strongly suggested by increasing 18o values between greece and afghanistan

amount effect recorded in oxygen isotopes of late glacial horse equus and bison bison teeth from the sonoran and chihuahuan deserts southwestern united states stable oxygen isotopes from fossils both vertebrate and invertebrate or inorganic sedimentary minerals frequently have been used to make interpretations about ancient global climates oxygen isotope values measured from terrestrial vertebrates or sedimentary carbonates provide information about paleotemperature and amounts of precipitation at a particular site in general these inferences are made on the centennial to millennial scale serial i e ontogenetic sampling of equus and bison tooth enamel provides climatic data on the scale of months to a few years we present models showing how annual environmental patterns of d 18 o would be replicated in the tooth enamel of equus and bison changes in d 18 o due to shifts in temperature in terrestrial environments d 18 o increases with increased temperature and amount and timing of precipitation increased precipitation may result in a decrease in d 18 o a phenomenon called the amount effect are archived in both equus and bison teeth the input signal is better resolved in bison due to its more rapid enamel growth modeled patterns are compared with actual data from modern sites in the sonoran and chihuahuan deserts of the southwestern united states the isotopic patterns from modern teeth agree with that predicted from known variations in meteoric water known floral and faunal assemblages as well as computer models suggest summer rain for the chihuahuan desert of late glacial time 15 000 10 000 years ago but little summer rain for the sonoran desert at that same time serial data from fossil teeth show a clear pattern interpreted to represent the amount effect that includes increased summer rains in the chihuahuan desert and only minor summer rains in the sonoran desert d 2004 elsevier b v all rights reserved

mobility of middle holocene foragers in the cis baikal region siberia individual life history approach strontium ratios rare earth and trace elements abstract previous geochemical work conducted on the materials from the khuzhir nuge xiv cemetery on lake baikal siberia has demonstrated the effectiveness of using 87 sr 86 sr ratio analysis in interpreting mobility patterns among early bronze age hunter gatherer groups the research reported here focuses on six small cemeteries representing the little sea and upper lena micro regions as well the early neolithic en ca 8000 7200 cal bp and early bronze age eba ca 5200 3400 cal bp periods thus expanding both the geographic and chronological scope of the previous work the reference collection of environmental samples to document bioavailability of the measured geochemical tracers was also expanded substantially by inclusion of samples of modern plants and water from lake baikal and a number of surrounding rivers first second and third molars of 14 adult individuals were tested for 87 sr 86 sr ratios as well as rare earth and trace element concentrations using la icp ms each human tooth was micro sampled at four locations along the crown enamel thus providing data of higher temporal resolution relative to a single sampling locus geochemical signatures for water plant and animal bone samples were found to be far more variable across the region than predicted based on the age and type of geologic formations 87 sr 86 sr ratios for cultural micro regions proved to overlap significantly and required trace element data to identify more discrete geochemical groups the level of hunter gatherer mobility between and within the analyzed micro regions was found to be significant with individuals recovered from the upper lena showing contact with the little sea micro region along the northwest coast of the lake

strontium isotope evidence of neanderthal mobility at the site of lakonis greece using laser ablation pimms we report here direct evidence for neanderthal mobility through the measurement of strontium isotope ratios in tooth enamel using laser ablation which allows us to use much smaller samples than traditional methods there has been a long standing debate over the extent of neanderthal mobility with some arguing for neanderthals having a very limited geographic range and others for more substantial and even seasonal lifetime movements we sampled across the enamel of a neanderthal third molar from the site of lakonis greece dating to ca 40 000 years ago the tooth was found in a coastal limestone cave yet the strontium isotope values indicate the enamel was formed while the individual resided in a region with bedrock consisting of older more radiogenic volcanic bedrock therefore this individual must have lived in a different more radiogenic location during this period of third molar crown formation likely to be between the ages of 7 and 9 years than where the tooth was found this strontium isotope evidence therefore indicates that this neanderthal moved over a relatively wide i e at least 20 km geographical range in their lifetime

the peak frequency of direct waves for microseismic events abstractdirect seismic waves p or s waves are used to locate and further characterize microseismic events the resolution of information obtained from direct waves depends on the peak frequencies of the waveforms the peak frequency results from combination of the source propagation and the receiver effects for frequencies below the corner frequency propagation effects control the peak frequency in observed seismograms of microseismic events the frequency dependence of direct body waves can be modeled by attenuation specifically the global attenuation factor this model is consistent with observed data along surface profiles explaining the difference between the peak frequencies of p and s waves in addition the model is consistent with the peak frequencies observed on downhole monitoring arrays this can be used to invert effective attenuation providing additional unique measurement from microseismic events the corner frequency can be estimated from the average stress drop and analytical sour

magnetostratigraphy of the middle miocene continental sedimentary sequences of the mae moh basin in northern thailand evidence for counterclockwise block rotation abstract a magnetostratigraphic study has been performed on the mae moh basin well known for its lignite mining in the lampang province paleomagnetic samples were collected from 66 stratigraphic levels rock magnetic investigations indicate the presence of low coercivity minerals specimens subjected to progressive thermal or alternating field demagnetization procedures show that nearly all of them exhibit a low temperature magnetization component and a high temperature characteristic component chrm with either positive or negative virtual geomagnetic pole latitudes and opposite polarity considered as the characteristic miocene magnetization the overall mean paleomagnetic direction incl 22 2 decl 358 3 15 95 4 documents a counterclockwise vertical axis rotation of about 13 1 32 with respect to the expected miocene direction derived from the eurasian polar wander curve incl 42 decl 11 our paleomagnetic results are not consistent with the previously reported paleomagnetic data the rotation observed in the mae moh basin can be the response to local tectonics a section sampled for magnetostratigraphy reveals a polarity sequence of nine magnetozones that can reliably be correlated to the geomagnetic polarity time scale according to biochronological constraints the magnetostratigraphic results from the mammal bearing succession correlate with chron c5abn c5an2n between 13 5 and 12 1 ma according to the mean sedimentation rate of about 17 5 cm ka ages of 12 5 and 12 8 ma are proposed for the fossiliferous levels j5 and k1 k2 lignite zones were the mammal remains were found

observations on the nature and origin of fusain abstract evidence for a wildfire origin of fusain is examined charcoal produced by natural fires and artificial charring resembles fossil fusain both in physical size and shape and in optical reflectance artificially charred leaves and naturally burnt wood are illustrated using the sem reflectance studies on modern charcoals suggest that much semifusinite may be produced by pyrolysis the ecological implications of a wildfire origin of fusain are discussed and it is concluded that fires have been a feature of terrestrial ecosystems from at least the late devonian

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

forward and inverse methods for extracting climate and diet information from stable isotope profiles in proboscidean molars abstract intratooth stable isotope profiles in enamel provide time series of dietary and environmental information that if correctly interpreted serve as archives of seasonal variability in past environments a major challenge in interpreting these profiles arises from time averaging imparted by enamel mineralization and developmental geometry whereby the primary 13c or 18o input signal is attenuated and shifted which can potentially lead to incorrect interpretations of the magnitude or frequency of seasonal variability several forward and inverse models have been developed to reconstruct the primary input signal from intratooth profiles in continuously growing teeth here the models developed by passey and cerling 2002 and passey et al 2005 are extended to molars of elephantinae which grow over a long but finite interval of time proboscidean molars are particularly attractive for intratooth profiles because they may contain a decade or more of information and they are often well preserved in the fossil record because of their thick enamel and large size forward model parameters are established using histological analysis of molar thin sections of extant african elephants loxodonta africana and a mammoth mammuthus columbi and by micro ct analysis of l africana molar plates the density of immature enamel is about 65 of the final density of mature enamel the appositional length varies from approximately 35 to 55 mm and the maturation length is about 70 mm histological methods are used to determine crown formation time cft in elephant and mammoth molar plates cft for the elephant and mammoth molar plates studied in thin section are about 5 6 years and 11 years which translate to mean growth rates of about 21 mm year and 16 mm year respectively coeval molar and tusk profiles from a zoo elephant are compared the tusk isotope profile serves as a proxy for the primary input signal and thus provides an opportunity to evaluate the forward and inverse models the results from the zoo elephant profiles demonstrate that the inverse model accurately reconstructs the amplitude and overall structure of the primary input signal inverse model results of mammoth molar profiles show double the range of 13c in measured enamel profiles inversion model results illustrate that improved reconstruction of the primary input signal can lead to more accurate interpretations of the seasonal variability of diet and body water and by extension vegetation and precipitation in past environments

pliocene early pleistocene climatic trends in the italian peninsula based on stable oxygen and carbon isotope compositions of rhinoceros and gomphothere tooth enamel abstract the pliocene and early pleistocene 5 2 1 ma palaeoclimate for localities in italy is evaluated using stable carbon and oxygen isotope compositions of tooth enamel of fossil specimens from rhinocerotidae stephanorhinus sp and gomphotheriidae anancus sp taxa carbon isotope composition was measured in the structural carbonate 13 c while oxygen isotope values were determined both in the structural carbonate 18 o co3 and the phosphate 18 o po4 of bioapatite the 13 c co3 values indicate that the taxa were grazers browsers of a pure c 3 vegetation low 13 c co3 values for central and north italy indicate a humid climate with woodlands and forest cover in the pliocene for northern localities the 13 c values increase between mn16a and mnq16b biozones most likely linked to the northern hemisphere glaciation at 2 7 ma after the mid pliocene warm period for central italy the values have a wide range with a long term increasing trend in the early pleistocene indicating more arid climate and or more open vegetation overall the 18 o po4 values in central italy change together with the 13 c co3 values and are taken to reflect the warmer wetter interglacials and cooler more arid glacial phases the 18 o po4 values in north italy are lower than those in central italy and show no clear temporal trend one explanation for the low values especially in mn14 15 biozone is that these 18 o po4 values do not reflect entirely the isotopic composition of local precipitation but river waters from the alps with 18 o depleted isotopic compositions or a n s directed rain shadow effect on the precipitation in general the new isotope data agree well with palaeoclimate reconstructions based on palynological and other proxies

pliocene and early pleistocene paleoenvironmental conditions in the pannonian basin hungary slovakia stable isotope analyses of fossil proboscidean and perissodactyl teeth abstract stable carbon and oxygen isotope values of structural carbonate 13c 18oco3 and phosphate 18opo4 in bio apatite were measured for fossil mammalian teeth from slovakia and hungary oxygen isotope compositions of enamel provide new quantitative records of the pliocene and early pleistocene paleoclimate in the pannonian basin pb the 18opo4 values were used to study the temporal variations in the oxygen isotope compositions of precipitation and the changes in temperature over the pb the new o isotope data suggest that surface air temperatures between 4 5 and 2 0 ma were 1 to 4 c warmer with about 700 mm yr more precipitation compared to the present c isotope analyses of samples from proboscideans anancus sp mammut sp and perissodactyls stephanorhinus sp tapirus sp from the pliocene mn15 mn16 and early pleistocene mn17 suggest that they were primarily c3 browsers the mean 13c value is high at 4 5 to 3 7 ma mn14 15 during the pliocene warm period and decreases at about 3 5 to 3 0 ma mn16 mid pliocene warm period with the onset of more humid conditions in europe the 13c values return to higher values from 2 5 ma onwards mn17 most likely reflecting more arid conditions as a consequence of the onset of the northern hemisphere glaciation

a depositional model for the mid westphalian a to late westphalian b coal measures of south wales mid westphalian a to late westphalian b sediments of the south wales coalfield comprise mainly lacustrine raised mire and flood deposits developed in an upper coastal plain environment occasional high sinuosity fine grained channel systems drained the subdued topography of the wales brabant massif to the north and east of the basin low sinuosity channels with lithic coarse grained fills drained a rising source to the south direct marine influence was restricted to a single marine band facies distributions were controlled by 1 local scale 10 2 10 3 m 2 autocyclic sedimentary processes 2 regional scale 10 km 2 synsedimentary fault activity and differential subsidence and 3 basin wide scale 10 2 km 2 response to changes in relative sea level base level changes are recorded by basin wide bivalve horizons up dip or landward extension of marine bands developed in lacustrine mudstones above basin wide coal seams peat accumulation was terminated by a water table rise related to base level rise following flooding re establishment of the clastic supply resulted in the gradual infilling of the basin wide lake to produce coarsening upwards cyclothems or parasequences a eustatic origin for parasequence development is supported by the development of identical facies associations and parasequences in coeval sediments from the pennine and midland valley coalfields

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

the source scanning algorithm mapping the distribution of seismic sources in time and space summary we introduce a new method which we call the source scanning algorithm ssa for imaging the distribution of seismic sources in both time and space using trial locations and origin times the method calculates the brightness function by summing the absolute amplitudes observed at all stations at their respective predicted arrival times the spatial and temporal distribution of sources is then identified by a systematic search throughout the model space and time for the maximum brightness the greatest advantages of this method are that 1 it exploits waveform information both arrival times and relative amplitudes without the need to calculate highfrequency synthetic seismograms and 2 it requires neither pre assembled phase picking data nor any a priori assumptions about the source geometry a series of tests using synthetic data have shown that this method is robust and can faithfully recover the input source configuration to within 1 grid interval finally we demonstrate the value of the algorithm by locating a typical tremor event with emergent waveforms that occurred during the recent episodic tremor and slip ets sequence in the northern cascadia subduction zone

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

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

comparison of migration based location and detection methods for microseismic events microseismic monitoring in the oil and gas industry commonly uses migration based methods to locate very weak microseismic events the objective of this study is to compare the most popular migration based methods on a synthetic dataset that simulates a strike slip source mechanism event with a low signal to noise ratio recorded by surface receivers vertical components the results show the significance of accounting for the known source mechanism in the event detection and location procedures for detection and location without such a correction the ability to detect weak events is reduced we show both numerically and theoretically that neglecting the source mechanism by using only absolute values of the amplitudes reduces noise suppression during stacking and consequently limits the possibility to retrieve weak microseismic events on the other hand even a simple correction to the data polarization used with otherwise ineffective methods can significantly improve detections and locations a simple stacking of the data with a polarization correction provided clear event detection and location but even better results were obtained for those data combined with methods that are based on semblance and cross correlation

volcanism and paleoenvironment of the pula maar complex a pliocene terrestrial fossil site in central europe hungary abstract we describe the late pliocene paleoenvironment and paleoclimate of the pula fossil site of the western pannonian basin hungary which occurs within a lacustrine succession deposited in a volcanic crater maar radiometric dating of adjacent volcanic bodies hosting the fossil bearing sedimentary assemblages gives an age of 4 25 0 17 ma k ar to date five articulated rhinoceros skeletons dihoplus sp have been recovered and a few fragmentary remains of artiodactyls and freshwater fishes perca sp leuciscus sp and gobius sp are also present an insect taphocoenosis comprises terrestrial groups that inhabited the former lake margins syrphidae heteroptera chalcidoidea tenebrionidae as well as aquatic insects dytiscidae baetidae and chironomidae deciduous broad leaved woody plants prevailed in and around the pula locality quercus ulmus zelkova acer salicaceae and are associated with some rare floral elements ginkgo sassafras and buxus deposition at the lake bottom seems to have taken place in oxygen depleted layers and taphonomic evidence indicates that fossil material underwent minimal if any weathering 13c values of one rhinoceros tooth suggest that this mammal consumed mixed c3 plants in a wooded environment the climatic conditions inferred from the reconstructed vegetation and stable oxygen isotope data from the tooth enamel support a cf type climate koppen classification with a mean annual temperature of 10 13 c with some dry periods during the year pula is comparable to other maar fossil sites of pliocene age such as camp dels ninots spain and hajnacka i slovakia

beyond the dots in the box microseismicity constrained fracture models for reservoir simulation summary monitoring of induced microseismic events usually results in locations for these events and a geometrical interpretation of these dots in the box in this study we show how additional information obtained from observed microseismic events namely the source mechanisms were used to generate a discrete fracture network using the wide aperture of a surface star like array fracstar allows inversion for both shear and non shear source mechanisms both volumetric and shear only source mechanism inversion was carried out on microseismic events from the treatment of a shale gas reservoir in the continental us during the same hydraulic fracture stimulation treatment both dip slip and reverse faulting sources were active in this reservoir the source mechanisms revealed fracture orientations more accurately than could be inferred from microseismic event locations alone the activity associated with different mechanisms is interpreted as indicating reactivation of existing fractures in the rock as well as suggesting generation of new fractures failure analysis using source mechanisms on individual events allows an integrated understanding of the complex fracture interactions taking place in the reservoir and also provides a more complete understanding of the stress conditions in the reservoir during the treatment fracture orientations locations and failure mechanisms are translated into discrete fracture network dfn models that can be used to verify the extent and character of the fractures created or reactivated during the fracture treatment and may ultimately be used to generate fracture flow properties for reservoir simulation

geochemistry of the late permian no 30 coal seam zhijin coalfield of southwest china influence of a siliceous low temperature hydrothermal fluid this paper describes the influence of siliceous low temperature hydrothermal fluid on the elemental concentrations and mineralogical characteristics of the late permian anthracitic ro max 3 58 coal seam no 30 from the zhijin coalfield in western guizhou province sw china coal samples were examined using instrumental neutron activation analysis inductively coupled plasma mass spectroscopy inductively coupled plasma atomic emission spectrometry x ray fluorescence powder x ray diffraction scanning electron microscopy equipped with energy dispersive x ray and isotope analysis the modes of occurrence of elements were determined using a sequential chemical extraction procedure the studies indicate that the no 30 coal seam has a very high content of veined quartz vol 9 4 whose isotope values of 30si and 18o are 0 6 and 15 4 respectively indicating that the quartz originated from siliceous low temperature hydrothermal fluid formation temperature 160 220 c rather than detrital material of terrigenous origin or magmatic hydrothermal inputs results of scanning electron microscopy equipped with energy dispersive x ray and sequential chemical extraction procedure show that the veined quartz is the dominant source of fe cu u pd pt and ir which are as high as 2 31 356 8 2 1 2 43 and 0 006 g g in this coal seam respectively the studies have also found that elements such as fe and cu are mainly in the veined quartz and they do not occur as sulfides in this coal seam in sharp contrast to many other coal seams in china the geochemical and mineralogical anomalies of the coal are attributed to the siliceous low temperature hydrothermal fluid

elemental and mineralogical anomalies in the coal hosted ge ore deposit of lincang yunnan southwestern china key role of n2 co2 mixed hydrothermal solutions abstract the lincang neogene high ge coal deposit in yunnan southwestern china is one of the major coal hosted ge deposits in the world this study reports new data on the petrological mineralogical and geochemical compositions of 57 samples including coal bench samples roofs floors partings and batholith granite of three high ge coal seams s3 z2 and x1 from the dazhai mine lincang ge ore deposit and provides new insights into the origin and modes of occurrence of the minerals and elements present the coals have huminite random reflectances in the 0 33 0 48 range on a mineral free basis the coal samples are dominated by huminite group macerals all having more than 88 5 total huminite ulminite and attrinite generally dominate the huminite macerals structured inertinite is rare with funginite being the most abundant inertinite form the minerals in the coals are mainly composed of quartz and to a lesser extent kaolinite illite and mica a hydrous beryllium sulfate phase beso 4 4h 2 o is present in the low temperature ashes of several coal samples compared to average values for world low rank coals beryllium up to 2000 g g and 343 g g on average ge up to 2176 g g and 1590 g g on average and w up to 339 g g and 170 g g on average are unusually enriched in the lincang coals with a concentration coefficient 100 cc ratio of element concentration in investigated coals vs world low rank coals elements as 156 g g on average sb 38 g g cs 25 2 g g and u 52 5 g g are significantly enriched 10 the biotite and two mica granites which served as both the basement for the coal bearing sequence and as a source of sediment input were also either hydrothermally altered or argillized the alteration appears to have taken place during or shortly after deposition of the coal bearing sequence two types of metasomatites of hydrothermal origin including quartz carbonate and carbonate were identified which occur as partings and as roof and floor strata these metasomatites were formed at the syngenetic or early diagenetic stages of coal deposition the rare earth elements in these hydrothermal rocks are characterized by a heavy ree enrichment type and by distinct positive eu anomalies compared to the upper continental crust hydrothermal solutions have played a significant role in producing the elemental and mineralogical anomalies in the lincang ge ore deposit the hydrothermal solutions leaching the batholith granite were a mixture of alkaline n 2 bearing and volcanogenic co 2 bearing fluids which led to the enrichment of trace elements not only including assemblages of ge w and be nb u both leached from granite and the deposited in the peat but also as sb from volcanogenic solution as well as the alteration and argillization of the batholith granites and the formation of carbonate and quartz carbonate metasomatites

marine derived 87sr 86sr in coal a new key to geochronology and palaeoenvironment elucidation of the india eurasia and china indochina collisions in yunnan china abstract coal has formed in terrestrial and coastal marine environments from sub polar to equatorial regions since the devonian it contains detailed long term records of contemporaneous environment climate and subsequent modifications however in general direct chronological information in coal has been sparse the coal investigated in the present study is from the mile intermontane basin yunnan province china north of an arm of the mesozoic tethys ocean the coal contains marine geochemical signatures and syngenetic gypsum common in coastal marine sediments the gypsum contains marine derived sr and hence has geochronological potential the 87sr 86sr record 0 708350 0 708591 in the mile coal agrees with time calibrated 87sr 86sr records of marine planktonic foraminifera obtained from core dsdp 588c 22 25 18 27 ma early miocene the peat of the mile coal was deposited over 4 6 ma which possibly is the longest deposition of a coal bed in the world to have been found today although this duration should include the period of non peat deposition or erosion if present during the time of the 4 6 ma during this period the regional geological structures were determined by the india eurasia collision which resulted in transform faults with extensive rift structures including the mile rhomb shaped graben this structural setting enabled the flow of seawater from the south china sea to reach inland graben structures including that of the mile basin where peat was deposited subsequent deformation caused by the south china indochina collision changed the regional structural and geographical hydrological patterns this affected the hydrology of the mile basin and resulted in its uplift to its present day elevation of 1350 m this study is to our knowledge the first to use the marine derived 87sr 86sr indicator and chronometer in coal at present marine influenced peats generated in coastal salt marshes extend from the arctic ocean alaska and siberia in the north to patagonia and new zealand in the south while mangrove forests abound in equatorial and low latitude coastal areas the 87sr 86sr record of marine influenced coal in this study area provides a key for the determination of age duration rate of geological processes in the inland basin associated with the closure of the tethys ocean results indicate that this method has potential for providing a temporal framework for geological events and processes in other areas these may be found near marine shore lines across the globe dating back to the devonian moreover the 87sr 86sr signal in marine influenced coal can be used for correlation with the well established 87sr 86sr chronology of marine planktonic foraminifera in turn the 87sr 86sr signal provides a basis for correlating terrestrial records of climate and environment contained in this type of coal and associated sediments with those of marine sediments such as those based on 18o in planktonic foraminifera

a self adjoint velocity stress full waveform inversion approach to microseismic source estimationmicroseismic source estimation abstractaccurate estimation of microseismic events in time and space enables important characterization of hydraulic fracture networks determining the orientation of the fracture can help differentiate between reactivation of an in situ fracture and a hydraulically induced fracture which is important in characterizing the effectiveness of the stimulation process we consider the source as separable in time and space and invert for a complete description of the source in one of these two dimensions assuming the other is known we recover the wavelet which includes the source amplitude and time evolution in space we recover a description of the source that is distributed and includes an estimate of the moment tensor at every point in the domain a change of variables applied to the velocity stress form of the elastic wave equation ensures that the system is self adjoint thus full waveform inversion can be tailored to estimate microseismic events with limited modifications to the forward wave solver

spatial and temporal variations in the isotopic composition of bison tooth enamel from the early holocene hudson meng bone bed nebraska the hudson meng bone bed in northwestern nebraska is an early holocene deposit of hundreds of bison of divering ages that were killed in a catastrophic event of unknown origin the m 1 m 2 and m 3 molars of individuals ranging from ca 1 to 7 years of age at the time of their death were examined to determine inter and intra tooth isotopic variability and to link this variability to time in order to better understand the environments that existed prior to the mass death event the d13c value of molar structural carbonate increases by 2 3 from the m 1 to m 3 molars reflecting increasing direct forage signals and decreasing maternal influences the d18o value of molar structural carbonate in a given individual shows no consistent trend with time from birth indicating a fairly direct linkage to dietary water regardless of tooth ontogeny detailed down tooth isotopic measurements indicate a small seasonal signal in the d13c value of forage maternal milk which appeared to have been largely dominated by c 4 flora in contrast there was almost a 10 range in the isotopic composition of dietary water a range that is within present day summer versus winter precipitation in the region the d18o value of bulk tooth enamel arranged by approximate time prior to the death event indicate a consistent increase in the d18o value of body water 2 3 suggesting a long term decrease in winter spring precipitation and or drought the d18o trend with time coupled with the high c 4 grass abundance suggest environmental stresses on the herd preceding the catastrophic death event 2000 elsevier science b v all rights reserved

mississippian anthracites in guangxi province southern china petrological mineralogical and rare earth element evidence for high temperature solutions abstract minerals and elements in coal are derived from the processes associated with peat accumulation and rank advance as well as possibly a range of epigenetic processes and thus can provide information on the depositional conditions and geologic history of coal beds and coal bearing sequences as well as perhaps on regional tectonics this paper investigates the petrology mineralogy and geochemistry of anthracites and their host rocks partings roof and floor strata from two coal deposits hongmao and luocheng in guangxi province southern china samples collected from these deposits were analyzed using optical microscopy scanning electron microscopy plus energy dispersive x ray spectrometry low temperature ashing x ray diffraction x ray fluorescence spectrometry and quadrupole based inductively coupled plasma mass spectrometry the anthracites from the two deposits are medium to high sulfur coals the rare earth elements in the luocheng anthracites are characterized by distinct positive eu anomalies and medium and heavy ree enrichment types the minerals in the hongmao anthracites are characterized by the occurrence of k illite paragonite and ammonian illite which however are absent in the luocheng anthracites the paragonite ammonian illite and chlorite resulted from the alteration of pre existing kaolinite by hot solutions containing na nh4 and fe2 respectively the partings in the luocheng anthracite seams contain pyrophyllite that was formed by reactions between kaolinite and quartz during injection of high temperature solutions the mineralogical and geochemical characteristics of the anthracites in the two deposits indicate that the coals were subjected to high temperature 250 c solutions that also elevated the coal rank to anthracite grade the assemblage of k illite paragonite nh4 illite in the coals of the hongmao deposit was formed under greater hydrothermal but less tectonic influence compared to the luocheng deposit by contrast the pyrophyllite illite chlorite assemblage of the luocheng deposit reflects a greater tectonic but lesser hydrothermal influence

micrinite in southern hemisphere sub bituminous and bituminous coals redefined as fine grained kaolinite a range of complementary analytical techniques including sem eds tem eds and conventional optical microscopy has been rigorously applied to precisely defined areas of micrinite in polished coal samples from australia and new zealand elemental analyses of micrinite regions showed a high abundance of al si and o and high resolution images of micrinite revealed a grain size 1 m electron diffraction and elemental analyses from individual grains within the optically and electron optically correlated micrinite regions are consistent with the occurence of fine grained kaolinite the optical properties of dark clay and micrinite i e fine grained kaolinite can be understood in terms of the diffuse scattering of visible light from the surfaces of materials with different grain sizes in single phase or multi phase mixtures

joint location and source mechanism inversion of microseismic events benchmarking on seismicity induced by hydraulic fracturing summary seismic monitoring can greatly benefit from imaging events with a low signal to noise ratio snr as the number of the events with a low signal grows exponentially one way to detect weaker events is improvement of a snr by migration type stacking of waveforms from multiple stations we have developed a new method of location of seismic events that involves stackingofseismicphasesandamplitudesalongdiffractiontraveltimecurvestosuppressnoise and detect seismic events with a snr lower than that on individual receivers the stacking includes polarity correction based on a simultaneous seismic moment tensor inversion and detection algorithm on the stack function we applied this method to locate microseismicity induced by hydraulic fracturing first we calibrated the velocity model by locating perforation shots at known locations then we processed 3 d of data from microseismic monitoring of shale stimulation and benchmarked migration type locations of the largest events that were manually located the detected and located events induced by hydraulic fracturing in this case study are mostly shear events forming narrow bands along the maximum horizontal stress direction approximately 100 m above the injection intervals the proposed technique is fully automated and feasible for real time seismic monitoring

facies and genesis of carboniferous coal seams of northwest germany abstract in order to get detailed information about the facies and genesis of upper carboniferous coal seams of northwest germany maceral analyses of complete seam profiles westphalian b d mainly westphalian c were carried out four main facies and twelve subfacies could be distinguished the main facies are 1 1 the sapropelic coal facies consisting of fine grained inertinite and liptinite which forms from organic sediments deposited at the bottom of moor lakes 2 2 the densosporinite facies which is high in inertinite and liptinite and low in vitrinite syngenetic pyrites clastic layers thick vitrains and fusains do not occur this facies originates from peats of open mires with higher groundwater table and herbaceous vegetation the open mire was situated in the centre of extensive swamps consequently clastic sedimentation did not affect this swamp type and nutrient supply and ph values were low 3 3 the vitrinite fusinite facies which is high in vitrinite this is the result of abundant vitrains under the microscope fusains were mostly identified as fusinite the vitrinite fusinite facies originates from a forest mire more or less abundant seam splits and clastic layers show that rivers flowed in the neighbourhood of this area 4 4 the shaly coal facies which represents the most marginal part of the former swamp frequently affected by clastic sedimentation within the carboniferous of the ruhr region it seems unlikely that the thin coal seams of the namurian c and westphalian a1 contain a densosporinite facies the swamps were situated in the lower delta plain where they were often affected by marine influences consequently coals are high in minerals and sulfur and they are thin and discontinous the best conditions for the formation of extensive swamps with open mires densosporinite facies in their central parts prevailed during westphalian a2 and b1 times low contents of sulfur and minerals and high content of inertinite are typical for these coals sedimentation mainly took place in the transitional zone from the lower to the upper delta plain during the westphalian b2 and c fluvial sedimentation dominated within the coal seams minerals sulfur and pseudovitrinite increase while inertinite decreases this is the consequence of coal of the densosporinite facies occurring with increased rarity the coal seams of the westphalian c2 contain no densosporinite facies because peat formation was restricted by increasing fluvial sedimentation and by a better drainage as a consequence extensive swamps with open mires in the centre were no longer formed after the formation of the odin seams above the odin seams coal of the vitrinite fusinite facies contains thick walled torisporinites variations and lowering of the groundwater table caused mild oxidative influences during peat formation this is documented by an increase in pseudovitrinite the occurrence of torisporinites and the absence of spheroidal sideritic concretions sulfur content increases in the absence of the low ash and low sulfur coal of the densosporinite facies in upper carboniferous coal seams of the ibbenburen region the inertinite and telocollinite contents are higher than in those of the ruhr region therefore variations of the groundwater table have been more pronounced and resulting oxidative influences must have been more severe seldom occurring marine and brackish horizons and a higher fusinite fusain content indicate a slight elevation of this area from early westphalian d times onward peat formation was no longer possible because of the better drainage this resulted in severe oxidative conditions which excluded peat formation

oxygen isotope analyses of co existing carbonate and phosphate in biogenic apatite a way to monitor diagenetic alteration of bone phosphate abstract the oxygen isotopic composition of phosphate 18 op and structural carbonate 18 oc of hydroxylapatite was determined in 31 bone and tooth samples of modern mammals from different countries these two variables are highly correlate r 2 0 98 and the calculated best fit of linear regression is very similar to the equation calculated from the phosphate and carbonate palaeotemperature equations 1 2 according to previous measurements 3 6 on fossils of different ages from different areas it seems quite improbable to find isotopically altered skeletal remains showing a good correlation between 18 op and 18 oc as is the case with modern samples it therefore seems possible at least in some cases to use these measurements for monitoring fossil bone and tooth diagenetic alteration when a set of points lie on the equilibrium line or close to it the 18 o values could be considered close to the original values in contrast when the points lie to the left or to the right of this line this probably means that the values are diagenetically modified due to interaction with meteoric water or 18 o enriched water respectively

variscan compressional structures within the main productive coal bearing strata of south wales the structure of the main productive coal measures within the anthracite zone in the western part of the south wales coalfield is re examined using data from recently operational opencast coal sites variscan thrusts and or folds and bed parallel shear structures are present within all of the sites studied at east pit unaffected by any large scale zone of disturbance bed parallel shear structures are developed along many of the gently dipping coal seams which form a series of simultaneously active detachments representing a process of easy slip thrusting a ne sw striking fold dominated disturbance at gilfach iago is interpreted to overlie a reactivated basement fault a more complex disturbance zone at ffos las combines both e w trending folds and more variably oriented thrusts which together shorten the coal bearing strata by up to 2 km and this is interpreted to be the major variscan frontal thrust ramp in the extreme west of the coalfield the variscan compressional structures within south wales are not consistent with a simple thin skinned thrust system the strain induced by deep seated variscan thrusts was distributed throughout much of the coal bearing sequence by easy slip deformation rather than being localized along a single regional detachment and additional thrusts present around the northern margin of the coalbasin appear to have formed as isolated autochthonous structures the inherent weakness of coal seams across south wales is attributed to the presence of greatly increased fluid pressures which would have been generated both by the maturing coal and by the influx of fluids along deep seated disturbance zones

environmental change and seasonal behavior of mastodons in the great lakes region inferred from stable isotope analysis abstract we investigate seasonal variations in the diet and drinking water of four great lakes mastodon mammut americanum specimens using stable isotope analysis of serially sampled inner enamel bioapatite structural carbonate 13 c sc 18 o sc and previously published bulk analyses isotopic analyses and thin section measurements showed that mastodon tooth enamel extension rates 12 4 mm yr decreasing toward the cervix were lower than those of mammoths or modern elephants mastodons had distinct and highly regular seasonal variations in 13 c sc and 18 o sc which we interpret in the context of local glacial history and vegetation changes seasonal variations in 18 o were large but variations in 13 c were small and may have been obscured if coarser sampling methods than our inner enamel sampling approach were used thus our approach may be particularly useful for understanding relatively small seasonal changes in 13 c within c 3 environments the seasonal patterns though not entirely conclusive suggest that the ontario mastodons did not migrate over very long distances rather the climate and seasonal dietary patterns of mastodons within the region changed over time from 12 400 to 10 400 14 c yr bp 15 000 12 000 cal yr bp insights gained using these methods can contribute to a better understanding of megafaunal extinctions and paleoamerican lifeways

inverse methods for estimating primary input signals from time averaged isotope profiles abstract mammalian teeth are invaluable archives of ancient seasonality because they record along their growth axes an isotopic record of temporal change in environment plant diet and animal behavior a major problem with the intra tooth method is that intra tooth isotope profiles can be extremely time averaged compared to the actual pattern of isotopic variation experienced by the animal during tooth formation this time averaging is a result of the temporal and spatial characteristics of amelogenesis tooth enamel formation and also results from laboratory sampling this paper develops and evaluates an inverse method for reconstructing original input signals from time averaged intra tooth isotope profiles the method requires that the temporal and spatial patterns of amelogenesis are known for the specific tooth and uses a minimum length solution of the linear system am d where d is the measured isotopic profile a is a matrix describing temporal and spatial averaging during amelogenesis and sampling and m is the input vector that is sought accuracy is dependent on several factors including the total measurement error and the isotopic structure of the measured profile the method is shown to accurately reconstruct known input signals for synthetic tooth enamel profiles and the known input signal for a rabbit that underwent controlled dietary changes application to carbon isotope profiles of modern hippopotamus canines reveals detailed dietary histories that are not apparent from the measured data alone inverse methods show promise as an effective means of dealing with the time averaging problem in studies of intra tooth isotopic variation

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

fluid migration and coal rank development in foreland basins mathematical modeling of regional fluid flow in the south wales foreland basin shows that heat was transferred from internal to peripheral parts of the basin where very high geothermal gradients and surface heat flow would have developed in the fluid discharge areas temperatures are modeled to have reached 300 c within the coal measures section and would have generated anthracite while more internal parts of the basin were cooled by descending fluid flow and temperatures of only 220 c resulted sufficient to form bituminous coal the modeled thermal regime appears to match the pattern of coal rank observed in the basin the regional flow probably continued for 1 to 2 m y before erosion diminished the topographic gradient driving brine migration in the late paleozoic

stable carbon and oxygen isotope analysis of fossil tooth enamel using laser ablation abstract a technique is described whereby the 13c and 18o values of fossil tooth enamel can be measured in situ using laser ablation techniques the laser heats the sample and forms co2 from structural carbonate apatite the 18o values obtained with this method are equal to those of the phosphate oxygen due to the high temperature of reaction during ablation analytical precision is approximately 0 5 for both 13c and 18o the spatial resolution is 200 m or less which may be reduced as the technical modifications are made this method allows the analysis of samples that previously could not be analyzed due to difficulty with sample preparation size or rare nature the apparent oxygen isotope fractionation between the carbonate and laser derived oxygen co3 laser is 1 0071 for biogenic apatite at 38 c determined using the in situ laser comparison of 18o co3 and 18o laser analyses with 18o laser and 18o po4 results suggest a fractionation factor co3 po4 of 1 0083 variations in the 18o and 13c values of single teeth can be easily determined with the in situ technique this will allow the study of changes in diets or water sources during the period of tooth growth which for larger mammals can be several years for the tooth row the 13c and 18o values are important in paleodiet and paleoecology studies they can be used to study resource partitioning within an ecosystem and can shed light on the life history strategies within living and extinct species

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

isotopic records of climate seasonality in equid teeth abstract we investigate how oxygen isotopes in equid teeth can be used as a record of seasonality first we use in situ laser ablation and conventional microsampling techniques to understand time averaging of environmental signals in intra tooth isotope profiles in modern feral horse teeth n 5 from mongolia where there is a large seasonal gradient in the oxygen isotopic composition of precipitation we demonstrate that laser ablation can be used to sample inner middle and outer enamel layers in large mammalian herbivore teeth the inner enamel layer records less attenuated isotopic signals than other layers as predicted by the mineralization patterns but intra tooth signal amplitude is similar for laser and conventional sampling methods second we use modern zebra teeth n 21 collected in eastern africa to evaluate how intra tooth oxygen isotope variation relates to rainfall patterns in the tropics we show that the intra tooth isotopic range increases with intra annual precipitation isotopic range which in turn relates to aridity in the equatorial bimodal rainfall region but is influenced by other hydroclimate processes in the region as a whole finally we address isotopic seasonality during the early pleistocene in eastern africa using oxygen isotopes in fossil equid teeth from southwestern kenya n 11 and northern tanzania n 5 we find variable isotopic seasonality in the past similar to present day eastern africa consistent with the notion that hominins and other mammals were able to accommodate environmental variability on intra annual scales in addition to well documented orbital cycles

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

mammoth tooth enamel growth rates inferred from stable isotope analysis and histology abstract mammoth mammuthus sp teeth are relatively abundant in quaternary deposits from eurasia and north america and their isotopic compositions can be used to reconstruct past seasonal patterns in precipitation diet and migration strategies for collecting and interpreting such data however are strongly dependent on growth rates which can vary among species individuals and within teeth in this study we use histological and isotopic measurements to determine enamel growth rates for a columbian mammoth mammuthus columbi tooth in two directions using histology the growth rate through the enamel thickness et perpendicular to the height of the tooth is estimated at 0 8 to 1 5 mm yr isotopic sampling through the innermost 0 36 mm of the et recovered less than half a period of variation i e half an inferred year of growth which is consistent with the histological estimate for et growth rate a combination of histological and isotopic measurements suggests that the enamel extension rate growth in the height of the tooth is 13 14 mm yr knowledge of enamel growth rates should improve the design and interpretation of future isotopic studies of mammoth teeth the combination of histological and isotopic measurements may also prove useful in determining growth rates for other extinct taxa

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

tooth enamel sampling strategies for stable isotope analysis potential problems in cross method data comparisons abstract the stable isotope composition of a given sample of tooth enamel is a function of the mineralisation process the isotopic composition of the input signal and sampling geometry as the dominant axis of tooth growth is orientated from the occlusal surface to the enamel root junction the isotopic composition of an enamel sample that spans the full length of this axis is often taken to represent a whole tooth or bulk average while serial or intra tooth samples taken along the same axis are considered to track isotopic variation across the period of tooth formation a bulk sample of enamel should therefore approximate the mean of the serial samples and in teeth that form over a complete annual cycle bulk and serial sampling methods are often assumed to possess an annual seasonal relationship however this does not take into account the effect of the mineralisation process and sampling geometry on the derived isotope signals here we investigate the reproducibility of both the bulk and serial sampling methods as independent stand alone techniques and then explore the assumed relationship between the two each method shows good reproducibility in the oxygen 18o and carbon 13c isotope results across paired left and right molars however cross method comparisons reveal a systematic offset between bulk and serial results within a single population with 19 out of 23 18o bulk tooth values being lower and 22 out of 23 13c bulk tooth values being higher than the means of their respective intra tooth sequences in 4 out of 19 cases for 18o and 6 out of 22 cases for 13c the bulk tooth results fall completely out of the range observed in the corresponding intra tooth sequence this finding has implications for cross method data comparisons and questions the assumed temporal relationship between serial and bulk isotope data

a mountain front model for the variscan deformation of the south wales coalfield access to the considerable geological database of british coal together with seismic evidence of subsurface relationships has enabled the development of a structural model for the south wales coalfield detailed site investigations are used as key examples the simple broad synclinal nature of the coalfield masks a more complex structural system thrusting of variscan age is largely confined to the lower and middle coal measures and throughout the central and northern coalfield is dominantly a forethrust system however along the south crop a major backthrust system is developed which in places penetrates the upper coal measures the south crop shows features analogous with a mountain front and is interpreted as a triangle zone in which pre existing basement faults have facilitated uplift the lack of thrusting within the upper coal measures in contrast to the underlying lower and middle coal measures suggests they have acted as a passive roof to the thrust system geographical variation in the intensity of the deformation can be related to the proximity of and buttressing against the caledonian massif although broadly analogous with current models of foreland basin development and deformation the south wales coalfield demonstrates the importance of pre existing massifs and lineaments in determining the precise evolution of an area

high quality surface microseismic data illuminates fracture treatments a case study in the montney monitoring hydraulic fracture stimulations from the surface is a technique that in the past met with mixed success one reason for this experience is that the measurement has often been treated as if it were only a minor variant of the reflection surveys our industry is most familiar with while reflection seismic sources are designed to generate primarily p waves fracturing rocks emit both p and s waves with the much larger proportion of energy as s waves to capture the information content in the microseismic wavefield surveys must be designed to record and processing strategies designed to use the full vector wavefield energy emitted by the fracture process to record the full vector wavefield requires the use of appropriate sensors capable of recording low frequencies and three components

reservoir characterization using surface microseismic monitoring microseismic monitoring of reservoir processes can be performed using surface or near surface arrays we review the published technical basis for the use of the arrays and the historical development of the method beginning with locating earthquakes through geothermal exploration to the growing field of hydraulic fracture monitoring practical considerations for the array deployment and data processing are presented the road ahead for the technology includes a move toward life of field buried arrays as well as opportunities for extended interpretation of the data particularly inversion for source mechanism estimation and measurement of anisotropy in the monitored subsurface

mineralogy and geochemistry of a late permian coal in the dafang coalfield guizhou china influence from siliceous and iron rich calcic hydrothermal fluids abstract this paper describes the influence of siliceous and iron rich calcic low temperature hydrothermal fluids lthf on the mineralogy and geochemistry of the late permian no 11 coal anthracitic r r 2 85 in the dafang coalfield in northwestern guizhou province china the no 11 coal has high contents of vein ankerite 10 2 vol and vein quartz 11 4 vol with formation temperatures of 85 and 180 c respectively indicating that vein ankerite and vein quartz were derived from low temperature calcic and siliceous hydrothermal fluids in two epigenetic episodes the vein quartz appears to have formed earlier than vein ankerite did and at least three distinct stages of ankerite formation with different ca sr and fe mn ratios were observed the two types of mineral veins are sources of different suites of major and trace metals scanning electron microscope and sequential extraction studies show that in addition to fe mg and ca vein ankerite is the dominant source of mn cu ni pb and zn in the coal and the contents of these five elements are as high as 0 09 and 74 0 33 6 185 and 289 g g respectively in contrast vein quartz is the main carrier mineral for platinum group elements pges pd pt and ir in the coal and the contents of pd pt and ir are 1 57 0 15 and 0 007 g g respectively sequential extraction showed a high pge content in the silicate fraction up to 10 4 g g pd 1 23 g g pt and 0 05 g g ir respectively it is concluded that the formation of ankerite and quartz and the anomalous enrichment of trace elements in the no 11 coal in the dafang coalfield guizhou result from the influx of calcic and siliceous low temperature hydrothermal fluids

reconstructing the migration patterns of late pleistocene mammals from northern florida usa abstract we used analyses of the strontium isotope 87sr 86sr ratios of tooth enamel to reconstruct the migration patterns of fossil mammals collected along the aucilla river in northern florida specimens date to the late glacial period and before the last glacial maximum pre lgm deer and tapir displayed low 87sr 86sr ratios that were similar to the ratios of florida environments which suggest that these taxa did not migrate long distance outside of the florida region mastodons mammoths and equids all displayed a wide range of 87sr 86sr ratios some individuals in each taxon displayed low 87sr 86sr ratios that suggest they ranged locally while other animals had high 87sr 86sr ratios that suggest they migrated long distances 150 km outside of the florida region mastodons were the only taxa from this region that provided enough well dated specimens to compare changes in migration patterns over time pre lgm mastodons displayed significantly lower 87sr 86sr ratios than late glacial mastodons which suggests that late glacial mastodons from florida migrated longer distances than their earlier counterparts this change in movement patterns reflects temporal changes in regional vegetation patterns

hydraulic stimulation of natural fractures as revealed by induced microearthquakes carthage cotton valley gas field east texas we produced a high resolution microseismic image of a hydraulic fracture stimulation in the carthage cotton valley gas field of east texas we improved the precision of microseismic event locations four fold over initial locations by manually repicking the traveltimes in a spatial sequence allowing us to visually correlate waveforms of adjacent sources the new locations show vertical containment within individual targeted sands suggesting little or no hydraulic communication between the discrete perforation intervals simultaneously treated within an 80 m section treatment i e fracture zone lengths inferred from event locations are about 200 m greater at the shallow perforation intervals than at the deeper intervals the highest quality locations indicate fracture zone widths as narrow as 6 m similarity of adjacent source waveforms along with systematic changes of phase amplitude ratios and polarities indicate fairly uniform source mechanisms fracture plane orientation and sense of slip over

tooth enamel biomineralization in extant horses implications for isotopic microsampling abstract isotopic analyses of tooth enamel from fossil equids are increasingly being used to reconstruct paleoclimatic and paleoenvironmental conditions however the accuracy of these reconstructions is currently limited partly because the precise timing and spatial patterns of enamel mineralization in equids have not been documented we used radiographic analyses of mandibles collected from modern juvenile and adult domestic horses equus caballus to document the timing of enamel mineralization in equid cheek teeth premolars and molars optical and radiographic analyses of thin sections of mature and developing teeth were used to document the spatial pattern of enamel mineralization in each tooth we found that the enamel layers in equine cheek teeth took longer to mineralize than had been previously assumed largely because the enamel continued to mineralize for approximately 6 to 12 months after each tooth had begun to erupt total enamel mineralization times for individual teeth ranged from 1 5 to 2 8 years examination of thin sections revealed that retzius striae extend outward from the enamel dentin junction at an angle of 5 to 10 and run near parallel to the nonocclusal surface of the tooth daily cross striations average 5 m in width suggesting that during the initial phase of enamel mineralization matrix formation new material is added at a rate of 5 m day radiographic analyses demonstrate that the secondary mineralization front enamel maturation front is orientated approximately parallel to the retzius striae but complete maturation i e full mineralization lags behind matrix formation by several weeks to months

moment tensor migration imaging we develop and apply an imaging procedure for simultaneous location and characterization of seismic source properties called moment tensor migration imaging the procedure constructs images for moment tensor components using a weighted diffraction stack migration and combines ray theoretical green s functions with a reverse time moment tensor imaging methodology by applying an approximation we term the ray angles only approximation we form an expression for moment tensor migration imaging where the migration weights depend only on the take off and arrival angles for rays leaving receiver positions and incident upon the image points moment tensor migration imaging retains the benefits of diffraction stack procedures for source location and characterization namely speed flexibility and the potential for incorporating non linear stacking procedures whilst also providing the benefits of moment tensor imaging such as the inclusion of multiple phase and multiple component data the collapsing of the source radiation pattern estimation of the moment tensor we examine variations of the imaging procedure through a synthetic test we show that although the assumptions required for the imaging and ray angles only approximation may not be strictly valid for realistic survey geometries a simple weight adjustment can be used to obtain more accurate and stable results in these situations in our synthetic example we find that the use of a p wave only migration without this reweighting structure produces poor results whereby the resulting images show activity upon incorrect moment tensor components however many of these effects are mitigated by use of the reweighting scheme and the results are further improved through the introduction of non linear stacking operators such as semblance weighted stacks the highest quality moment tensor images for the synthetic test examined here are obtained through the use of both p wave and s wave wave fields this highlights the importance of multicomponent data and multiphase modelling when characterizing seismic sources we also find that the imaged moment tensor components vary proportionately when the input velocities are perturbed by a scale factor this suggests for the geometry investigated here derived source properties such as fault plane solutions and shear tensile components will not be influenced by bulk changes in seismic velocities finally we show the application to a real microseismic event observed using a surface array during hydraulic fracturing we find that the procedure collapses the seismic radiation pattern into an anomaly with a maximum at the hypocentre and our derived mechanism is consistent with the observed radiation pattern from the source

on the retrieval of moment tensors from borehole data the complete moment tensors of seismic sources in homogeneous or vertically inhomogeneous isotropic structures cannot be retrieved using receivers deployed in one vertical borehole the complete moment tensors can be retrieved from amplitudes of p waves provided that receivers are deployed in at least three boreholes using amplitudes of p and s waves two boreholes are in principle sufficient similar rules also apply to transversely isotropic media with a vertical axis of symmetry in the case of limited observations the inversion can be stabilized by imposing the zero trace constraint on the moment tensors however this constraint is valid only if applied to observations of shear faulting on planar faults in isotropic media which produces double couple mechanisms for shear faulting on non planar faults for tensile faulting and for shear faulting in anisotropic media the zero trace constraint is no longer valid and can distort the retrieved moment tensor and bias the fault plane solution numerical modelling simulating the inversion of the double couple mechanism from real data reveals that the errors in the double couple and non double couple percentages of the moment tensors rapidly decrease with increase in the number of boreholes used for noisy p and s wave amplitudes with noise of 15 of the top amplitude at each channel and for a velocity model biased by 10 the errors in the double couple percentage attain 25 13 and 6 when inverting for the double couple mechanism from one two and three boreholes

the preservation of glacial interglacial climatic signatures in the oxygen isotopes of elephant skeletal phosphate abstract phosphate 18o values 18op of modern elephant bone and teeth are found to vary linearly according to the 18o of local meteoric water 18omw a parameter with close ties to regional and local climatic conditions enamel dentine cementum and bone separates from individual fossil elephant specimens of late pleistocene age have op values which vary by up to elephant specimens the larger spread in the 18op values of the various skeletal phases for the fossil samples is interpreted as evidence for post depositional alterantion of primary 18op signatures of some if not all of these fossil skeletal components in the fossil samples investigated enamel and dentine phases have systematically lower 18o values than associated bone and cementum phases differential re equilibration with soil waters either by the wholesale replacement of primary apatite or by processes of isotopic exchange is suggested as a mechanism to account for the observed spread in the fossil phosphate 18o data

real time earthquake location using kirchhoff reconstruction real time location of earthquakes can be achieved by using direct imaging of the recorded wave field based on a kirchhoff reconstruction method similar to that used in the migration of seismic reflection data the standard method of event location requires the wave arrival at each sensor to be picked and associated with an event by using direct imaging the event is identified once in the imaged wave field the computation is independent of the level of seismic activity and can be carried out on a typical desktop computer the procedure has been successfully demonstrated in two and three dimensions using data from the southern california seismic network trinet at higher resolutions the reconstruction method can identify finite source effects further work considers extending the method by implementing full elastic theory and solving for moment tensors at all locations in the mesh

asian monsoons in a late eocene greenhouse world the strong present day asian monsoons are thought to have originated between 25 and 22 million years myr ago driven by tibetan himalayan uplift however the existence of older asian monsoons and their response to enhanced greenhouse conditions such as those in theeocene period 55 34myrago are unknownbecause of the paucity of well dated records here we show late eocene climate records revealing marked monsoon like patterns in rainfall and wind south and north of the tibetan himalayan orogen this is indicated by low oxygen isotope values with strong seasonality in gastropod shells and mammal teeth from myanmar and by aeolian dust deposition in northwest china our climate simulations support modern like eocene monsoonal rainfall and show that a reinforced hydrological cycle responding to enhancedgreenhouse conditions counterbalanced the negative effect of lowertibetanrelief onprecipitation these strong monsoons later weakened with the global shift to icehouse conditions 34myr ago

dental histology of late miocene hipparionins compared with extant equus and its implications for equidae life history abstract hipparionins were a dominant element of the late miocene faunas of europe however their biology and ecology remain incompletely understood in this paper we explore the pace of life history of different sized hipparionin horses using dental histology and compare it with extant equids in doing so we consider i the size diversity of hipparionins ii their generally smaller size compared to extant equids and iii the allometric coupling between size and life history in particular we reconstruct the dental growth in lower first second molars and in later formed lower third molars for three hipparionin taxa two dwarf species hipparion periafricanum and h gromovae and a larger species h concudense we also analyze dental growth in an extant zebra equus quagga for comparative purposes our results reveal that within each species there are differences in enamel growth parameters between the first second molars and third molars these results illustrate the differences in the developmental timing of these teeth and the existence of a relationship between dental growth parameters with somatic growth we also find that hipparionin teeth grow at slower rates and tend to erupt later in time than in extant equus dwarf hipparionins moreover exhibit lower enamel extension rates than the larger species but similar formation and eruption times considering the link between dental development and life history these results suggest a slower pace of growth of selected hipparionins compared to extant equids and a further slower life history than expected for their size in the two dwarf forms