geochemistry and nano mineralogy of feed coals mine overburden and coal derived fly ashes from assam north east india a multi faceted analytical approach abstract in order to address the scarcity of information on the nature and mode of occurrence of minerals and elements in coal coal mine overburden and coal ashes from north east india and also the relations between coal mineralogy and ash chemistry the petrology mineralogy and nano mineralogy and ash chemistry of some industrially important high sulfur coals mine overburden materials and fly ash samples from assam india have been evaluated a combined approach using petrography low temperature ashing plus x ray diffraction lta xrd field emission scanning electron microscopy fe sem high resolution transmission electron microscope hr tem raman spectroscopy and inductively coupled plasma mass spectrometry icp ms has provided new information on the mineralogy and nano mineralogy of these sub bituminous coals and associated mine overburden the presence of rare earth elements and yttrium rey in northeast indian coal mine overburden and fly ash samples is also reported for the first time the identification of these components may be significant from an economic point of view some northeast indian fly ashes with ree oxides up to 1580 ppm on an ash basis might possibly represent sources for recovery of rare earth elements

the motion of rigid ellipsoidal particles in slow flows abstract preferred orientations of fabric elements in tectonites are usually interpreted with reference to two continuum models namely those of march 1932 and jeffrey 1922 it is argued that the first of these is usually inappropriate if the fabric elements are rigid inhomogeneities embedded in a deformable matrix jeffrey s model is more applicable but until recently its use has been limited to problems involving axisymmetric particles and simple flow geometries in this paper jeffrey s equations have been solved numerically in order to investigate the behaviour of more general systems the motions of two particle shapes one a prolate spheroid the other a triaxial ellipsoid are considered in parallel for four specified flow geometries which involve pure or simple shear and combinations of both any departures from particle axisymmetry or from simple flow geometries have a significant effect on particle behaviour compared with that predicted by spheroid simple flow solutions

platinum group elements in tulameen coal british columbia canada nickel sulfide fire assay neutron activation analysis and lead fire assay direct current plasma spectroscopy were used to determine platinum group elements pge and gold in 30 channel samples and 23 fault related samples from the blakeburn opencast mine south central british columbia canada in the majority of the channel samples concentrations of os ir ru rh pd and re were below detection pt in the coal ranged from below detection to 170 ppb and au from below detection to 38 ppb concentrations of all the pge with the exception of ru were on average higher in the coals than in the sediments in the deformed coal samples os ru rh and re were typically below detection anomalous values of pt up to 10 000 ppb were determined in three deformed coal samples and pd and ir were comparatively enriched in the majority of deformed coal samples up to 6 100 and 22 ppb respectively compared with channel samples on the basis of sem edx and comparisons with ash and organic matter contents it is likely that pt and au are present in the coal as discrete particles precipitated from circulating ground waters on contact with the organic rich reducing and low ph environment of the coal pt and au distributions appear to be related to sources of the elements in ground water i e interbedded volcanic units and the tulameen ultramafic complex for pt and interbedded clastic sedimentary units for au enhanced concentrations of pt and pd occur in coal samples associated with two faults

geochemistry and mineralogy of coal in the recently explored zhundong large coal field in the junggar basin xinjiang province china abstract the zhundong coalfield is a very large coal deposit currently under exploration and promises to be an important coal mining resource in western china the coal reserves amount to 164 gt at xiheishan and wucaiwan the coal bearing units are the badaowan lower jurassic and especially the xishanyao formations middle jurassic these contain from one to 31 coal seams one to 10 workable coals reaching the rank of high volatile a bituminous with an accumulated workable coal thickness of 20 87 m these recently explored coal reserves are of a high quality and are characterized by low ash aluminum iron sulfur and trace element contents the minerals present in this coal are mainly quartz kaolinite siderite and pyrite the trace element contents in both xiheishan and wucaiwan coals are much lower when compared with the usual concentration ranges present in chinese coals with the exception of ba and sr thus ba contents in xiheishan coal are higher than swaine s worldwide concentration range a large number of elements have mainly aluminosilicate affinity and occur in clay and other detrital coal minerals ca and mn have mainly carbonate affinity fe and s have mainly sulphide affinity in wuchaiwan coal in xiheishan fe mn and mg have mainly carbonate affinity siderite and probably b co ni and s have an organic affinity thus the zhundong coalfield contains coal with a very high quality and very low levels of impurities the very low ash yields s fe and trace element contents may be attributed to the sedimentological setting with intensive peat bog aggradation in a very shallow lake environment with a low detrital supply the very low sulfur content the relatively high ba sulfate barite content and the high siderite occurrence in xiheishan coal in contrast to the pyrite occurrence in wucaiwan coal may be attributed to the rapid aggradation of peat with the consequent oxidation and leaching of minerals elements and degradation of organic components under this scenario sulfate is trapped by the continuous precipitation and accumulation of barium sulfate very low soluble

the fate of sediment wood and organic carbon eroded during an extreme flood colorado front range usa identifying and quantifying the dominant processes of erosion and tracking the fate of sediment wood and carbon eroded during floods is important for understanding channel response to floods downstream sediment and carbon loading and the influence of extreme events on landscapes and the terrestrial carbon cycle we quantify sediment wood and organic carbon oc from source to local sink following an extreme flood in the tectonically quiescent semi arid colorado usa front range erosion of 500 000 m3 or as much as 115 yr of weathering products occurred through landsliding and channel erosion during september 2013 flooding more than half of the eroded sediment was deposited at the inlet and delta of a water supply reservoir resulting in the equivalent of 100 yr of reservoir sedimentation and 2 loss in water storage capacity the flood discharged 28 mg c km2 producing an event oc flux equivalent to humid tectonically active areas post flood remobilization resulted in a further 100 yr of reservoir sedimentation plus export of an additional 1 3 mg c km2 of wood demonstrating the ongoing impact of the flood on reservoir capacity and carbon cycling pronounced channel widening during the flood created accommodation space for 40 of flood sediment and storage of wood and eroded carbon we conclude that confined channels normally dismissed as transport reaches can store and export substantial amounts of flood constituents

effects of experimental deformation on the remanent magnetization of sediments abstract changes in direction and in intensity of the remanent magnetization of sediments were studied during experimental deformation leading to an axial shortening of 20 30 the remanence was produced before shortening by anhysteretic magnetization in an alternating field of 90 mt superimposed on a parallel steady field of 1 mt at various inclinations with respect to the sample the samples were sandstones marls and volcanic sediments the results show that the direction of magnetization is stable during the deformation within the experimental precision the intensity of magnetization decreases during shortening by an amount which depends on the type of rock about 30 for sandstones and about 5 for marls and volcanic sediments the march model does not account for the data and a discontinuous deformation must be invoked the evolution of the young modulus of sandstones during cyclic loading and unloading shows first a decrease in relation to crack density growth then an increase showing a localization of the fracturation and finally a deformation by displacement of microblocks an interpretation is given after a discussion of the results obtained by other authors with plasticine and artificial clays the amplitude of the decrease and of the rotation of the remanent magnetization could be a function of the size of the magnetic grains compared with the scale of the fracturation during non homogeneous processes of deformation

leaching experiments to study the release of trace elements from mineral separates from chinese coals abstract leaching experiments were carried out for two samples of mineral separates from chinese coals for the purpose to simulate the release of trace elements in acid mine drainage the leaching solution has a ferric ion concentration of 10 3 m ph 2 the experiments were carried out at room temperature the grain size of the mineral separates is 75 130 m the behavior of the release of eight trace elements co ni zn cd al cr as and pb were measured during the period of 312h the results from four leaching tests using two samples with two solid to liquid ratios show that the concentrations of co ni zn and cd continuously increased during the leaching period and they were correlated with the sulfate content in the same leachate this indicates that the elements were released during the oxidation and dissolution of pyrite the elements were easily dissolved in the leaching solution on the other hand the concentrations of al cr as and pb in the leachates varied considerably under same leaching conditions and were sensitive to the condition of the leachate during the leaching process the release of these four elements was affected by the ph of the leachate and by absorption and co precipitation they are less likely to migrate therefore the release and migration of the eight elements in acid coal mine drainage are controlled mainly by three factors the oxidation of pyrite the ph of the leachate and mineralogy of country rocks

geochemistry of source rock controlled late triassic coal an example from the dabaoding coal mine in panzhihua sichuan province southwestern china abstract the geochemistry of source rock controlled coals from the late triassic daqiaodi formation in the dabaoding coal mine of the southwestern sichuan province was investigated a total of 15 coal samples 6 parting samples and 4 roof and floor rock samples from the d15 3 and d18 coals were subjected to proximate and ultimate analyses for coal quality by using lta xrd with siroquant software for minerals xrf for major element oxides icp ms for trace elements icp cct ms for as and se ise for f and a dma 80 analyzer for hg results indicate that the dabaoding d15 3 and d18 coals are classified as low ash and low volatile bituminous coal minerals in coals are dominated by quartz kaolinite illite and dolomite most trace elements in the dabaoding coals are depleted or at normal levels relative to chinese coals or world hard coals except for cr with slight enrichment the dabaoding coals and host rocks are characterized by weakly positive ce and y anomalies strongly positive gd anomalies and weakly negative eu anomalies based on paleogeographical mineralogical and geochemical evidence the sediment source rocks of the daqiaodi coal bearing strata are identified as the panzhihua trachyte at the top of the kangdian upland which exerted crucial impacts on the dabaoding coals

efficient transport of fossil organic carbon to the ocean by steep mountain rivers an orogenic carbon sequestration mechanism mountain building exposes fossil organic carbon oc fossil in exhumed sedimentary rocks oxidation of this material releases carbon dioxide from long term geological storage to the atmosphere oc fossil is mobilized on hillslopes by mass wasting and transferred to the particu late load of rivers in large fl uvial systems it is thought to be oxidised in transit but in short steep rivers that drain mountain islands oc fossil may escape oxidation and re enter geological storage due to rapid fl uvial transfer to the ocean in these settings the rates of oc fossil transfer and their controls remain poorly constrained here we quantify the erosion of oc fossil from the taiwan mountain belt combining discharge statistics with measurements of particulate organic carbon load and source in 11 rivers annual oc fossil yields in taiwan vary from 12 1 to 246 22 tc km 2 yr 1 controlled by the high physical erosion rates that accompany rapid crustal shortening and frequent typhoon impacts effi cient transfer of this material ensures that 1 3 0 1 10 6 tc yr 1 of oc fossil exhumed in taiwan is delivered to the ocean with 15 loss due to weathering in transit our fi ndings suggest that erosion of coastal mountain ranges can force effi cient transfer and long term re accumulation of oc fossil in marine sediments further enhancing the role of mountain building in the long term storage of carbon in the lithosphere

a mineralogical and geochemical study of three brazilian coal cleaning rejects demonstration of electron beam applications abstract the background and anthropogenic levels of hazardous elements in the surface soil of a coal mining area depend on the geological setting of the region and the underlying soil material but may also be influenced by water borne or aeolian transport of sediment from adjacent coal related waste piles very few studies have focused on the chemical and mineralogical composition of brazilian coal cleaning rejects ccrs which may represent significant sources of soil or water contamination in this study we have investigated the quantitative distribution of minerals and potentially hazardous elements in ccrs and a run of mine coal from the brazilian states of rio grande do sul and santa catarina the major minerals identified by x ray diffraction xrd high resolution transmission electron microscopy hr tem and field emission scanning electron microscopy energy dispersive x ray analysis techniques fe sem eds are kaolinite quartz mixed layer illite smectite pyrite jarosite melanterite gypsum rutile and calcite while minor minerals include barite hematite siderite sphalerite and goethite galena magnetite zircon and many other species may also occur as accessory trace minerals pyrite and jarosite are relatively abundant in some cases making up to around 4 or 5 of the mineral matter with jarosite melanterite and gypsum probably formed by complex interaction of oxidation products from fe sulfides and clay or carbonate components initiated by exposure and storage of the host material such atmospheric exposure promotes sulfide oxidation that releases substantial sulfate loads as well as ca 2 k mg 2 cl and al 3 metals with the most severe discharges were zn cu mn co ni and cd most of the trace pollutants in the ccrs displayed a ph dependent solubility being immobile in near neutral samples but mobile under the low ph conditions associated with oxidized material the results highlight the complex interactions among mineral matter components of the ccrs during storage and the potential for release of potentially hazardous elements in association with longer term exposure and storage

tropical cyclone driven erosion of the terrestrial biosphere from mountains the transfer of organic carbon from the terrestrial biosphere to the oceans via erosion and riverine transport constitutes an important component of the global carbon cycle measurements of particulate organic carbon load and composition in the liwu river taiwan during cyclone triggered floods suggest that tropical cyclones may facilitate the delivery of non fossil particulate organic carbon to the ocean and its subsequent burial the transfer of organic carbon from the terrestrial biosphere to the oceans via erosion and riverine transport constitutes an important component of the global carbon cycle1 2 3 4 more than one third of this organic carbon flux comes from sediment laden rivers that drain the mountains in the western pacific region3 5 this region is prone to tropical cyclones but their role in sourcing and transferring vegetation and soil is not well constrained here we measure particulate organic carbon load and composition in the liwu river taiwan during cyclone triggered floods we correct for fossil particulate organic carbon using radiocarbon and find that the concentration of particulate organic carbon from vegetation and soils is positively correlated with water discharge floods have been shown to carry large amounts of clastic sediment6 non fossil particulate organic carbon transported at the same time may be buried offshore under high rates of sediment accumulation7 8 9 we estimate that on decadal timescales 77 92 of non fossil particulate organic carbon eroded from the liwu catchment is transported during large cyclone induced floods we suggest that tropical cyclones which affect many forested mountains within the intertropical convergence zone10 may provide optimum conditions for the delivery and burial of non fossil particulate organic carbon in the ocean this carbon transfer is moderated by the frequency intensity and duration of tropical cyclones

nanominerals and ultrafine particles from coal fires from santa catarina south brazil abstract coal mining in santa catarina south brazil impacted the environment by means of a large number of coal waste piles emplaced over the old mine sites and the adjacent areas of the criciuma urussanga and sideropolis poor disposal of coal cleaning rejects represents significant environmental concerns due to their potential influence on soils and river sediments as well as on the surface and groundwater in the surroundings of these zones in this research advanced analytical techniques were performed to provide an improved understanding of the complex processes related with sulfide rich coal waste oxidation spontaneous combustion sequences of mineral formation and the transport mechanisms of hazardous elements by neoformed soluble nanominerals and ultrafine particles the results showed the presence of massive amorphous si al fe ti zr oxy hydroxides and fe hydr oxides with goethite and hematite with various degrees of crystallinity containing hazardous elements such as cr hf hg mo ni se pb th u zr and others several of the neoformed nanominerals found in the burned coal rejects are the same as those commonly associated with coal mine drainage in which oxidation of sulfides plays an important role to environment and human health this is the first brazilian coal spontaneous combustion research

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

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

base saturation nutrient cation and organic matter increases during early pedogenesis on landslide scars in the luquillo experimental forest puerto rico we evaluate data from a chronosequence study of landslide scars ranging in age from 1 55 yr in the luquillo experimental forest lef a subtropical lower montane wet forest sensu holdridge in eastern puerto rico surface mineral soil 0 10 cm base saturation index bsi values increase during primary succession in the lef r 0 85 p 0 001 both bsi values and major nutrient cation concentrations are extremely low on new landslide scars during the course of the 55 yr chronosequence major nutrient cation concentrations are positively correlated with soil organic matter som content p 0 079 and not with clay content p 0 794 when data collected from plots representing the two dominant late succession vegetation associations are added to the analysis nutrient cation concentrations correlate significantly with both som p 0 001 and clay content p 0 033 our data show that when initial conditions are oligotrophic both nutrient cation pools and bsi values can increase in the surface mineral soil during early pedogenesis we discuss exogenic litter input substrate weathering and precipitation as potential sources for nutrient cations in these soils we further suggest that production and decomposition of som is the dominant process controlling capture retention and intra ecosystem cycling of nutrient cations in these forests

the record of triassic charcoal and other evidence for palaeo wildfires signal for atmospheric oxygen levels taphonomic biases or lack of fuel abstract as wildfires are today important sources of disturbance in many terrestrial ecosystems it is of great interest to understand how different environmental parameters and fire activity interacted during past periods of the earth history fossil charcoal inertinites and pyrogenic polycyclic aromatic hydrocarbons pahs represent the only direct evidence for the occurrence of such palaeo wildfires in the present study a review of published data together with new data on the occurrence of fossil charcoal for the permian and the triassic is presented for a long time it has been speculated that an assumed lack of evidence for palaeo wildfires during the triassic should be explained by a large drop in atmospheric oxygen concentration following or during the end permian mass extinction event preventing the occurrence of wildfires however evidence for palaeo wildfires is relatively common in many middle and late triassic strata whereas such evidence is almost totally lacking from early triassic sediments the interpretation of this charcoal gap or depression is difficult as many factors e g atmospheric oxygen concentration taphonomical biases lack of sediments suitable for the preservation of macroscopic charcoal lack of fuel and ignorance of scientists may have influenced not only the production but also the preservation and recovery of evidence for palaeo wildfires during this period thus it is not clear whether this early triassic charcoal gap can also be seen as evidence for an assumed wildfire gap or not without any doubt further investigations on the early triassic record of charcoal and other evidence for palaeo wildfires will be necessary before this problem can be solved in fact it can be expected that the number of published records of early triassic evidence for palaeo wildfires will increase in the future as more and more scientist working on sediments of this age may become aware of the interest in fires from this time this will certainly make it possible to give a much better picture of the temporal and regional distribution of wildfires during this period in the future

enrichment and distribution of elements in the late permian coals from the zhina coalfield guizhou province southwest china abstract this paper investigates the mineralogy and geochemistry of four coal beds wjb 6 wjb 7 fhs 23 and fhs 27 coals of the late permian in the zhina coalfield western guizhou province china the investigated coals reach the semianthracite anthracite coal rank and have super low to low ash yields the sulfur contents vary considerably through coal sections and are mostly in the range of medium high sulfur coal the mineral assemblage present in the fhs 23 and fhs 27 coals is mainly made up of pyrite and rectorite the wjb 6 and wjb 7 coals have different mineralogy with kaolinite and rectorite dominant in the former as well as quartz and rectorite in the latter these coals contain high concentrations of nb and ta but li is only enriched in the wjb 6 coal rectorite and anatase in these coals are important hosting phases of nb and ta while kaolinite and to a lesser extent chamosite in the wjb 6 coal are dominant carriers for the elevated li concentration the terrigenous material input the marine influence and the effect of circulating hydrothermal solution are the pivotal geological factors causing geochemical anomalies in coals investigated the high sulfur coals were subjected to an enhanced marine influence in the depositional environment as well as to a higher terrigenous influx when compared with the medium sulfur and low sulfur coals resulting in higher concentrations of s fe as mo u hg in the former coals than in the latter ones the anomalous enrichment of nb and ta in these coals as well as of li in the wjb 6 coal is the result of the contributions from ascending hydrothermal solutions although source rocks e g high ti basalt may provide relatively high background abundances of nb ta and li

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

geological controls on mineralogy and geochemistry of the late permian coals in the liulong mine of the liuzhi coalfield guizhou province southwest china abstract this paper investigates the mineralogical and geochemical compositions of the late permian coals in the liulong mine liuzhi coalfield western guizhou province china by using xrd sem edx icp aes and icp ms both the no 3 and no 7 coals are classified as low volatile bituminous coal however the no 3 coal is a medium ash 29 8 on average and high sulfur 4 76 on average coal while the no 7 coal is a low ash 12 4 on average and medium sulfur 2 16 on average coal major minerals in both coal seams include quartz pyrite marcasite kaolinite calcite and to a lesser extent gypsum and anatase illite chlorite rectorite albite ankerite and siderotil are only present in the no 3 coal the no 3 coal contains higher elemental concentrations than the no 7 coal probably due to the higher mineral contents in the no 3 coal and is enriched in nb and ta and to a lesser extent in k ti li v co cu sr zr mo and ba the mineralogical and geochemical data presented in this study have shown that the no 3 coal was formed under a higher degree of marine influenced coal forming environment than the no 7 coal however the both coals have the kangdian upland made of mafic igneous rocks such as basalt rocks as sediment source region like other coals from guizhou province three geological factors control the geochemical patterns of the no 3 and no 7 coals namely 1 the high detrital input in the no 3 coal causing high ash yields 2 the sediment source region kangdian upland basalt causing high ti nb and ta contents and a minor proportion of co cr v and cu when combined with the high detrital input in the no 3 coal 3 the higher degree of marine influenced depositional environment in the no 3 coal causing a high s sr and ba contents

tectonic strain and paleomagnetism experimental investigation a porous clay rich sandstone with a natural remanent magnetisation shows complex changes in the orientation of the remanence vector when the sandstone is subjected to experimental deformation at 100 mpa room temperature and constant natural strain rates of 1 10 5 s 1 the paleomagnetic vector does not simply rotate away from the axis of compression when the rock is shortened perpendicular to bedding the remanence vector rotates toward the bedding as expected but the remanence also rotates toward bedding when the rock is shortened parallel to bedding moreover in some cases the remanence vector changes azimuth within the specimen during experimental deformation thus bedding anisotropy and the accompanying mineral fabric anisotropy are more influential than strain in controlling deflections of the paleomagnetic vector in this study this anisotropy also influences the post deformational behaviour of remanence 4 months after deformation some cores shortened perpendicular to bedding relaxed their remanence vectors back towards the pre deformational attitude whereas some other cores continued to show progressive changes intragranular recoverable elastic strains in the magnetic grains may be partly responsible for the experimentally induced deflections of remanence

characterization of intrusive rocks and ree geochemistry of coals from the zhuji coal mine huainan coalfield anhui china abstract rare earth element ree concentrations in coals are a source of information relevant to the evolution of source rocks depositional environment and epigenetic tectonic activity as well as the effects of igneous intrusions in this study 186 coal samples 11 intrusion affected coal samples 4 samples representative of the intrusive rocks one coal roof and one parting samples were collected from 29 boreholes at the zhuji coal mine huainan coalfield anhui province china the main objective is to characterize the intrusive rocks in the coal bearing sequence and to investigate the correlation of ree parameters in the coals with the source rocks depositional environment localized faults igneous intrusions and thickness of the coal beds a sequence from base to top of acidic to basic intrusive rocks through the coal bearing strata was identified which possibly corresponds to different intrusive episodes of granite diorite monzonite and gabbro both the ree contents and degree of fractionation of light rare earth elements lree and heavy rare earth elements hree increase from acidic to basic rocks most rocks are slightly depleted in ce but highly depleted in eu the ree concentrations in coals from the zhuiji mine average of 118 g g are nearly identical to recently updated average chinese values but significantly higher than global values the ree content of the intrusion affected coals is not distinctively different from that of the other coals p 0 2 and ree concentrations of the igneous rocks appear to have no clear relationship to those of the intrusion affected coals the depositional environment and source rocks are presumably the main ree contributors to the coal accumulation basin the ree content in coals from fault affected boreholes is higher than that in other boreholes and this trend is stronger in the coal seams of the upper strata the hree tend to be incorporated into thinner coal seams and the degree of fractionation between lree and hree of the coal forming materials increases with coal thickness

decadal carbon discharge by a mountain stream is dominated by coarse organic matter rapid erosion in mountain forests results in high rates of biospheric particulate organic carbon poc export by rivers which can contribute to atmospheric carbon dioxide drawdown however coarse poc cpoc carried by particles 1 mm is rarely quantified in a forested pre alpine catchment we measured cpoc transport rates and found that they increase more rapidly with water discharge than fine poc 1 mm and dissolved organic carbon doc as a result decadal estimates of cpoc yield of 12 3 1 9 t c km 2 yr 1 are higher than for fine poc and doc even when excluding 4 extreme flood events when including these floods cpoc dominates organic carbon discharge 80 most cpoc 69 was water logged and denser than water suggesting that cpoc has the potential to contribute to long term sedimentary burial global fluxes remain poorly constrained but if the transport behavior of cpoc shown here is common to other mountain streams and rivers then neglecting cpoc discharge could lead to a large underestimation of the global transfer of biospheric poc from land to ocean

the use of sequential extraction to determine the distribution and modes of occurrence of mercury in permian huaibei coal anhui province china sequential extraction tests using a flow injection mercury system fims were done on 34 samples collected from the number 3 4 5 7 and 10 coal seams in the huaibei coalfield average total mercury hg concentrations for the seams were 0 13 0 18 0 54 0 34 and 0 19 mg kg respectively the average value for all of the coal samples was 0 26 mg kg which is higher than most chinese and u s coals six modes of hg occurrence were recognized including water leachable ion exchangeable organic bound carbonate bound silicate bound and sulfide bound hg with rare exception little hg was found in water soluble ion exchangeable or carbonate bound forms sulfide bound hg and organic bound hg dominated seams 3 4 and 10 whereas silicate bound hg dominated seams 5 and 7 the relatively high hg values observed in seams 5 and 7 especially in parting samples are attributed to hg enrichment by magmatic intrusions

simple shear experiments on magnetized wax hematite samples c a e s s laboratoire de geophysique interne uniuersite de rennes 1 f 35042 rennes francereceived july 1 1991 revision accepted may 28 1992abstractwe present the results of a series of simple shear experiments on hematite bearing paraffin wax samples homogeneousand continuous deformation was obtained up to a shear strain value of y 1 4 by deforming the samples in atemperature controlled bath and at a constant strain rate of 9x10 5 s r during deformation hematite plateletsprogressively rotate which has been checked by measuring the anisotropy of magnetic susceptibility ams principalsusceptibility directions tend to parallel the corresponding principal strain directions and ams intensity increases withincreasing strain this supports the idea that the hematite population develops a preferred orientation by progressive rigidrotation within the paraffin matrix before each deformation step an isothermal remanent magnetization irm was given to the samples within ara finite strain plane the containing the shear direction and normal to the shear plane with various initial angles to theshear direction ranging from 0 to 180 after each deformation step the irm was measured it showed no deflectiontowards the a finite strain direction in contrast it did show a systematic rotation within the ara plane always in the samesense as the rotation of strain axes e g counterclockwise in sinistral shear furthermore irm deviation is of the sameorder of magnitude for each initial direction from 0 to 180 this contradicts the passive behaviour model that haspreviously been shown to hold for irm in coaxially deformed samples finally we show that in the shear strain range of ourexperiments y 0 to 1 4 the deviation of irm depends only on the shear value and not on its initial direction and thatthis deviation is equal to the rigid rotation angle of the shear strain tensor

high quality of jurassic coals in the southern and eastern junggar coalfields xinjiang nw china geochemical and mineralogical characteristics abstract the junggar coal basin with enormous coal reserves is one of the largest coal basins in xinjiang province northwest china according to the exploration data there is one to dozens of workable coal seams developed in the xishanyao formation of middle jurassic across the whole basin with the maximum accumulated coal thickness of over 100 m ninety six bulk coal samples from six exploration boreholes in the southern and eastern junggar coalfields were collected to investigate the coal qualities of the junggar coals the mineralogical characteristics of the studied coals were determined by powder x ray diffraction xrd and geochemical analyses are performed by means of inductively coupled plasma atomic emission spectrometry icp aes and inductively coupled plasma mass spectrometry icp ms the eastern and southern junggar bituminous coals are all characterized by low ash yields low s contents and low mineral contents furthermore the concentrations of most major and trace elements in both the eastern and southern junggar coals are relatively low with respect to other chinese and worldwide coals with the exceptions of sr and ba the results show that elements including k li ti sc v cr ga rb zr pb and rare earth elements rees have aluminosilicate affinities ca bearing and fe bearing carbonate affinities are deduced for ca mg fe mn sr and ba sulfur fe zn pb cu and as show a partial sulfide affinity in some coals an apatite and or crandallite affinity is deduced from relatively high correlation of p sr and ba the very high coal quality of junggar coals is attributed to very low detrital supply in very stable shallow lake sedimentary facies during peat accumulation slight differences of peat bog accumulation rate water table and oxidizing reducing condition account for the merging and splitting of coal seams in different coal exploration areas and the slight differences of mineral s ash and trace element contents in summary the eastern and southern junggar coals with very enormous reserves are characterized by high quality which is significantly and environmentally relevant to coal combustion by products ccps and potential emissions of gaseous pollutants particulate matter during the large coal consumption in pulverized coal combustion power stations in xinjiang province the high coal quality of the junggar coals is expected to generate ccps that can be reused for various purposes with low environmental threat

mineralogy and geochemistry of a superhigh organic sulfur coal yanshan coalfield yunnan china evidence for a volcanic ash component and influence by submarine exhalation abstract the mineralogy and geochemistry of a superhigh organic sulfur shos coal of late permian age from the yanshan coalfield yunnan province southwestern china have been studied using optical microscope low temperature ashing plus x ray diffraction analysis scanning electron microscope equipped with energy dispersive x ray spectrometer a sequential chemical extraction procedure and inductively coupled plasma mass spectrometry the m9 coal from the yanshan coalfield is a shos coal that has a total sulfur content of 10 12 11 30 and an organic sulfur content of 8 77 10 30 the minerals in the coal consist mainly of high temperature quartz sanidine albite muscovite illite pyrite and trace amounts of kaolinite plagioclase akermanite rutile and dawsonite as compared with ordinary worldwide bituminous coals and anthracite and chinese coals the m9 coal is remarkably enriched in b 268 g g f 841 g g v 567 g g cr 329 g g ni 73 9 g g mo 204 g g and u 153 g g in addition elements including se 25 2 g g zr 262 g g nb 20 1 g g cd 2 07 g g and tl 2 03 g g are also enriched in the coal occurrence of high temperature quartz sanidine muscovite and illite in the m9 coal is evidence that there is a volcanic ash component in the coal that was derived from acid volcanic ashes fallen into the swamp during peat accumulation occurrence of albite and dawsonite in the coal and strong enrichment of some elements including f s v cr ni mo and u are attributed to the influence by submarine exhalation which invaded along with seawater into the anoxic peat swamp abundances of lithophile elements including rare earth elements nb y zr and tio2 indicate that the silicate minerals in the coal were derived from the northern vietnam upland to the south of the basin

a carbon storage perspective on alluvial sediment storage in the rhine catchment abstract floodplains are important sinks in terms of the sediment and carbon flux in fluvial systems despite the large amount of detailed geomorphological studies which include measurements on total organic carbon little is known of the coupling of long term carbon and sediment flux and on the amount of carbon storage in floodplains therefore the influence of the sedimentary facies in fluvial systems was investigated based on a statistical analysis of 1948 organic carbon measurements in different parts of the rhine catchment the analysis allows to develop a conceptual carbon budget model of fluvial systems which was coupled with a holocene alluvial sediment budget to estimate the holocene sequestration rates of carbon storage in floodplains averaged over the rhine catchment the sedimentary carbon sequestration ranges between 3 4 to 25 4 g m 2 yr 1 with more reasonable values between 5 3 to 17 7 g m 2 yr 1 compared to the recent particulate carbon export these values are in the same order of magnitude but somewhat smaller indicating that approximately the same amount of the exported carbon may be stored in floodplains however compared to sedimentary carbon sequestration rates obtained elsewhere the presented values are at the lower limit corresponding to the lower mean holocene soil erosion and floodplain accumulation rates

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

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

geochemistry of platinum group elements in marine oil shale from the changshe mountain area china implications for modes of occurrence and origins abstract the shengli river changshe mountain oil shale zone located in the north qiangtang depression northern tibet plateau represents a potentially largest marine oil shale resource in china eighteen samples including oil shale and micritic limestone were collected from the changshe mountain oil shale to determine the concentrations the modes of occurrence and origins of platinum group elements pges in marine oil shale the oil shale samples from the changshe mountain area exhibit low total pge contents ranging from 3 196 to 8 071 ng g with a weighted mean value of 5 383 ng g while the micritic limestone samples from the changshe mountain area exhibit a little lower ranging from 0 471 to 5 669 ng g pges in oil shale samples are characterized by high contents in pd 3 23 ng g pt 1 60 ng g and os 0 32 ng g as compared to rh 0 083 ng g ru 0 112 ng g and ir 0 043 ng g the individual pges of oil shale samples from the changshe mountain area exhibit various modes of occurrence ru and ir are mainly controlled by clay minerals and partly present as sulfide rh is mainly associated with sulfide and possibly present as clay minerals pt is associated with clay minerals and sulfide and pd is controlled by organic matter and pyrite while os is mainly present in organic matter three possible sources of pges were identified in oil shale seams in the changshe mountain area ru and ir are mainly terrigenous inputs rh and pt are derived from mixed sources seawater and terrigemnous supply while pd and os are mainly derived from seawater the terrestrial source of the oil shale seams in the changshe mountain oil shale was the suowa formation limestone and the nadi kangri felsic volcanic rocks

loading and fate of particulate organic carbon from the himalaya to the ganga brahmaputra delta abstract we use the evolution of river sediment characteristics and sedimentary corg from the himalayan range to the delta to study the transport of corg in the ganga brahmaputra system and especially its fate during floodplain transit a detailed characterisation of both mineral and organic particles for a sampling set of river sediments allows taking into account the sediment heterogeneity characteristic of such large rivers we study the relationships between sediment characteristics mineralogy grain size specific area and corg content in order to evaluate the controls on corg loading contributions of c3 and c4 plants are estimated from corg stable isotopic composition 13corg we use the evolution of 13corg values from the himalayan range to the delta in order to study the fate of corg during floodplain transit ganga and brahmaputra sediments define two distinct linear relations with specific area in spite of 4 5 times higher specific area ganga sediments have similar corg content grain size and mineralogy as brahmaputra sediments indicating that specific area does not exert a primary control on corg loading the general correlation between the total corg content and al si ratio indicates that corg loading is mainly related to 1 segregation of organic particles under hydrodynamic forces in the river and 2 the ability of mineral particles to form organo mineral aggregates bed and suspended sediments have distinct 13corg values in bed sediments 13corg values are compatible with a dominant proportion of fossil corg derived from himalayan rocks erosion suspended sediments from himalayan tributaries at the outflow of the range have low 13corg values 24 8 average indicating a dominant proportion of c3 plant inputs in the brahmaputra basin 13corg values of suspended sediments are constant along the river course in the plain on the contrary suspended sediments of the ganga in bangladesh have higher 13corg values 22 4 to 20 0 consistent with a significant contribution of c4 plant derived from the floodplain our data indicate that during the plain transit more than 50 of the recent biogenic corg coming from the himalaya is oxidised and replaced by floodplain corg this renewal process likely occurs during successive deposition erosion cycles and river course avulsions in the plain

geomorphic tectonic control of sediment discharge to the ocean the importance of small mountainous rivers analysis of data from 280 rivers discharging to the ocean indicates that sediment loads yields are a log linear function of basin area and maximum elevation of the river basin other factors controlling sediment discharge e g climate runoff appear to have secondary importance a notable exception is the influence of human activity climate and geology on the rivers draining southern asia and oceania sediment fluxes from small mountainous rivers many of which discharge directly onto active margins e g western south and north america and most high standing oceanic islands have been greatly underestimated in previous global sediment budgets perhaps by as much as a factor of three in contrast sediment fluxes to the ocean from large rivers nearly all of which discharge onto passive margins or marginal seas have been overestimated as some of the sediment load is subaerially sequestered in subsiding deltas before the proliferation of dam construction in the latter half of this century rivers

experimental simple shear deformation of magnetic remanence abstract a series of shear box experiments were run on magnetic rock analogues to determine how the remanence vector behaves during simple shear strain samples of silicone putty and silicone putty magnetite and kaolinite magnetite mixtures were given an anhysteretic remanence at high moderate and low angles to the shear plane in order to determine if the magnetization deformed as a passive line marker or as if carried by actively rotating rigid grains out of a total of twenty experiments twelve unequivocally contradict passive line behavior with an additional two experiments in strong disagreement with passive rotation of the magnetic particles when compared to numerical modeling results nine experiments clearly support active rotation of rigid magnetic particles thus in settings where simple shear may have been a dominant component of deformation history active rotation of remanence carrying grains rather than passive line behavior may be an appropriate description of the deformation of the remanence vector

in stream geomorphic structures as drivers of hyporheic exchange 1 common in stream geomorphic structures such as debris dams and steps can drive hyporheic exchange in streams exchange is important for ecological stream function and restoring function is a goal of many stream restoration projects yet the connection between in stream geomorphic form hydrogeologic setting and hyporheic exchange remains inadequately characterized we used the models hec ras modflow and modpath to simulate coupled surface and subsurface hydraulics in a gaining stream containing a single in stream geomorphic structure and to systematically evaluate the impact of fundamental characteristics of the structure and its hydrogeologic setting on induced exchange we also conducted a field study to support model results model results indicated that structure size background groundwater discharge rate and sediment hydraulic conductivity are the most important factors determining the magnitude of induced hyporheic exchange followed by geomorphic structure type depth to bedrock and channel slope model results indicated channel spanning structures were more effective at driving hyporheic flow than were partially spanning structures and weirs were more effective than were steps across most structure types downwelling flux rate increased linearly with structure size yet hyporheic residence time exhibited nonlinear behavior increasing quickly with size at low structure sizes and declining thereafter important trends in model results were observed at the field site and also interpreted using simple hydraulic theory thereby supporting the modeling approach and clarifying underlying processes

redwoods restoration and implications for carbon budgets abstract the coast redwoods sequoia sempervirens of california have several unique characteristics that influence interactions between vegetation and geomorphic processes case studies using a combination of in channel wood surveys and an air photo inventory of landslides illustrate current conditions in a redwood dominated watershed undergoing restoration work and the influence of wood loading and landslides on the carbon budget redwood trees have extremely large biomass trunk wood volumes of 700 to 1000 m3 and are very decay resistant consequently they have a large and persistent influence on in channel wood loading large wood surveys indicate high wood loading in streams in uncut forests 0 3 0 5 m3 m2 of channel but also show that high wood loading can persist in logged basin with unlogged riparian buffers because of the slow decay of fallen redwoods through a watershed restoration program redwood national park increases in channel wood loading in low order streams but the effectiveness of this technique has not yet been tested by a large flood another unique characteristic of redwood is its ability to resprout from basal burls after cutting so that root strength may not decline as sharply following logging as in other types of forests an air photo inventory of landslides following a large storm in 1997 indicated 1 that in the redwood creek watershed the volume of material displaced by landslides in harvested areas was not related to the time elapsed since logging suggesting that the loss of root strength was not a decisive factor in landslide initiation 2 landslide production on decommissioned logging roads was half that of untreated roads and 3 landslides removed an estimated 28 mg of organic carbon km2 from hillslopes the carbon budget of a redwood dominated catchment is dominated by the vegetative component but is also influenced by the extent of mass movement erosion control work and in channel storage of wood

mineral speciation and fate of some hazardous contaminants in coal waste pile from anthracite mining in portugal the coal anthracite a in douro coalfield nw of portugal has been exploited for many years and has been mainly used as fuel supply by a thermal power plant the mining activities inevitably impacted the environment which includes a large number of coal waste piles emplaced over the old mine sites and adjacent areas of the douro coalfield the disposal of coal mining residues represents significant environmental concerns due to their potential influence on soils and sediments as well as on the surface and groundwater of the surrounding areas in the present study the development of sequential extraction combined with various advanced analytical techniques was performed to provide an improved understanding of the complex processes related with sulfide rich coal waste oxidation sequences of mineral formation and the transport mechanisms of hazardous elements by specific neoformed soluble minerals the results showed the presence of amorphous iron oxy hydroxides and goethite with various degrees of crystallinity containing hazardous elements such as as cr hg mo se pb u and others some of the neoformed minerals found in the coal waste material are the same as those commonly associated with coal acid drainage in which oxidation of sulfides plays an important role the precipitated neoformed minerals include pickeringite blodite and a mixture of epsomite pickeringite and hexahydrite as these sulfates may dissolve after the first rain they may release above mentioned elements into surrounding water bodies

some geochemical indicators for discrimination between diagenetic and hydrothermal metalliferous sediments abstract two types of metalliferous sediments are known hydrothermal associated with tectonic faults and diagenetic enriched in precipitates from seawater they are similar in their appearance and chemical composition only the first type is an indicator for hydrothermal discharge therefore in exploration criteria for differentiating between the two are needed four possible indicators have been investigated and are discussed a differences in p y correlation b differences in cr zr correlation c different distribution patterns of ree and d different as contents the as content is easy to determine and seems to be at the present time the most suitable criterion for determining the genesis of the metalliferous sediments

wood export varies among decadal annual seasonal and daily scale hydrologic regimes in a large mediterranean climate mountain river watershed abstract the dynamics that move wood through and out of watersheds are complex and not yet fully understood in this study climatic conditions hydrologic responses and watershed processes were explored to better understand variations in wood export using aerial imagery event based video monitoring and field measurements from the 1097 km2 mountainous mediterranean climate north yuba river california watershed and its reservoir near the downstream outlet over a 30 year study period 198 5 2014 volumetric estimates of annual wood export into the reservoir available for a subset of years were used to investigate watershed scale wood export dynamics variations in annual peak discharge explained 79 of the variance in interannual wood export with 84 of total observed wood export ca 10 000 m3 of wood per event delivered by three discharge events of 19 year 21 5 year and 60 year flood recurrence intervals continuous video monitoring conducted during snowmelt season periods in 2010 and 2011 yielded wood discharge observations at minima 15 of statistical bankfull flow while maximum daily discharge explained 55 of observed daily wood piece variation no statistically significant wood discharge differences were found in snowmelt season observations likely because of domination of the hydrograph by diurnal pulses within the seasonal cycle a conceptual model and functional framework are introduced in support of a watershed scale explanation of wood export transport and storage processes applicable to large mediterranean climate mountain watershed settings

landslide impact on organic carbon cycling in a temperate montane forest in humid forested mountain belts bedrock landslides can harvest organic carbon from above ground biomass and soil ocmodern while acting to refresh the landscape surface and turnover forest ecosystems here the impact of landslides on organic carbon cycling in 13 river catchments spanning the length of the western southern alps new zealand is assessed over four decades spatial and temporal landslide maps are combined with the observed distribution and measured variability of hillslope ocmodern stocks on average it is estimated that landslides mobilized 7 6 2 9 tc km 2 yr 1 of ocmodern 30 of which was delivered to river channels comparison with published estimates of ocmodern export in river suspended load suggests additional erosion of ocmodern by small shallow landslides or overland flow in catchments the exported ocmodern may contribute to geological carbon sequestration if buried in sedimentary deposits landslides may have also contributed to carbon sequestration over shorter timescales 100 years 5 4 3 0 tc km 2 yr 1 of the eroded ocmodern was retained on hillslopes representing a net carbon sink following re vegetation of scar surfaces in addition it was found that landslides caused rapid turnover of the landscape with rates of 0 3 of the surface area per decade high rates of net ecosystem productivity were measured in this forest of 94 11 tc km 2 yr 1 which is consistent with rapid landscape turnover suppressing ecosystem retrogression landslide ocmodern yields and rates of turnover vary between river catchments and appear to be controlled by gradients in climate precipitation and geomorphology rock exhumation rate topographic slope copyright 2011 john wiley sons ltd

organic carbon fluxes to the ocean from high standing islands the transfer of terrestrially derived yet poorly quantified organic carbon to the oceans is an important yet unagreed upon proportion of the world s carbon budget the few data that exist suggest that high standing oceanic islands in the southwest pacific may make important contributions to the overall terrestrial flux of particulate organic carbon poc to the oceans we have determined the poc flux from several streams in new zealand with those data and previous measurements from taiwan and papua new guinea we estimate the poc flux from high standing islands in the southwest pacific to be 48 1012 g c yr 1 a value slightly lower than previous estimates these islands which make up only 3 of earth s landmass contribute 17 35 of the estimated poc entering the world s oceans annually and thus may be important sources of terrestrial carbon to the ocean anthropogenic activities especially deforestation and forest harvesting have probably exacerbated the natural flux few to no data exist for many of these islands and thus a more detailed assessment awaits further measurements

impact of hydrologically driven hillslope erosion and landslide occurrence on soil organic carbon dynamics in tropical watersheds the dynamics of soil organic carbon soc in tropical forests play an important role in the global carbon c cycle past attempts to quantify the net c exchange with the atmosphere in regional and global budgets do not systematically account for dynamic feedbacks among linked hydrological geomorphological and biogeochemical processes which control the fate of soc here we quantify effects of geomorphic perturbations on soc oxidation and accumulation in two adjacent wet tropical forest watersheds underlain by contrasting lithology volcaniclastic rock and quartz diorite in the luquillo critical zone observatory this study uses the spatially explicit and physically based model of soc dynamics tribs eco triangulated irregular network based real time integrated basin simulator erosion and carbon oxidation and measurements of soc profiles and oxidation rates our results suggest that hillslope erosion at the two watersheds may drive c sequestration or co2 release to the atmosphere depending on the forest type and land use the net erosion induced c exchange with the atmosphere was controlled by the spatial distribution of forest types the two watersheds were characterized by significant erosion and dynamic replacement of upland soc stocks results suggest that the landscape underlain by volcaniclastic rock has reached a state close to geomorphic equilibrium and the landscape underlain by quartz diorite is characterized by greater rates of denudation these findings highlight the importance of the spatially explicit and physical representation of c erosion driven by local variation in lithological and geomorphological characteristics and in forest cover this article is protected by copyright all rights reserved

occurrence and origins of minerals in mixed layer illite smectite rich coals of the late permian age from the changxing mine eastern yunnan china abstract minerals in coals from the changxing mine of eastern yunnan southwestern china were investigated using low temperature ashing plus x ray diffraction lta xrd optical microscopy and scanning electron microscopy with an energy dispersive x ray spectrometer sem edx the results show that minerals in the changxing coals include mixed layer illite smectite i s quartz kaolinite dolomite mg bearing siderite anatase ammonium illite k illite calcite and chamosite as well as minor amounts of hematite paragonite k feldspar and an al hydroxide mineral gibbsite the changxing coals are typically rich in mixed layer i s accounting for an average of 47 2 in their low temperature ashes mixed layer i s occurs mainly in two types 1 lentoid as thin beds and 2 fractures or cells fillings the type 1 is of terrigenous detrital origin and probably related to the weathering products of the emeishan basalt while the type 2 is of epigenetic origin and precipitated from hydrothermal fluids of a mafic magma intrusion the high k and poor na in the type 1 mixed layer i s indicate that it is in a higher evolution stage than the type 2 ammonium illite k illite and paragonite are probably products of dissolution and recrystallization of mixed layer i s while mg bearing siderite and partly chamosite are related to the fe mg al and si released from the evolution of mixed layer i s

geochemistry of late triassic coals in the changhe mine sichuan basin southwestern china evidence for authigenic lanthanide enrichment abstract five thin coals of late triassic age occur in the changhe mine sichuan basin southwestern china petrology and geochemistry of these coals and their roof parting and floor samples were studied the results show that the changhe coals are enriched in as 8 9 11 8 g g w 2 2 11 2 g g pb 20 8 48 2 g g and th 7 5 18 8 g g the source of these elements is possibly the xuefeng old land which is an early paleozoic source area southeast of the sichuan basin two tonsteins were found in the changhe mine one is the roof k8r of the k8 coal which is a pure kaolinitic claystone the other is the claystone k9c above the roof of the k9 coal which is mainly made up of mixed illite smectite minerals the ree content 287 9 g g of the k8 coal is much higher than that of its roof 153 6 g g sem edx results show that authigenic monazite and kaolinite are the main carriers of ree in the k8 coal on the basis of coal chemistry and occurrence of the precipitated minerals it is likely that leaching of the k8r tonstein occurred it is possible that trace elements including be 8 4 g g zr 302 g g nb 26 g g hf 9 7 g g th 18 8 g g u 5 8 g g ga 16 1 g g and pb 48 2 g g in the k8 coal were also elevated by the leachate of its overlying tonstein k8r the k9c tonstein with a total thickness of 16 cm is widely distributed in the changhe mine and serves as a distinct marker bed for correlation of coal seams besides mixed illite smectite minerals trace amounts of euhedral zircon anatase apatite and massive silica with vesicular structure were also examined these constitute strong evidence for its felsic volcanic ash origin

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

experimental and numerical modeling of irm rotation in deformed synthetic samples abstract the effect of strain upon isothermal remanent magnetization irm carried by hematite particles embedded in a plasticine matrix has been investigated magnetized artificial hand samples were deformed by simple coaxial shortening after deformation the hand samples were cut into 8 15 specimens and each specimen s irm measured hence a mean irm direction was obtained for each shortening step the main results are 1 when the initial direction of irm is parallel to the shortening axis 3 the hand sample mean irm stays parallel to 3 during deformation however individual magnetization directions are deflected towards the flattening plane and thus the specimen directions are scattered by strain this is accompanied by a significant decrease of magnetization intensity 2 in contrast when the initial direction of irm is perpendicular to 3 the shortening results in a clustering of specimen magnetization directions the mean direction being unchanged this is accompanied by a slight increase of magnetization intensity 3 in all other cases where initial irm direction makes an intermediate angle with shortening direction deformation induces a deviation of each specimen irm toward the flattening plane this results in an overall deflection of hand sample mean irm the amount of rotation increases with strain intensity changes of grouping and intensity depend on the initial angle between irm and 3 defining a continuum in behavior between irm directions being either parallel to 3 or perpendicular to 3 finally it is shown that all the experimental changes in irm due to deformation direction grouping intensity can be modeled by a passive marker rotation of hematite planar particles

mineralogical and geochemical responses of coal to igneous intrusion in the pansan coal mine of the huainan coalfield anhui china the huainan coalfield where magma is commonly intruded into the coal measures in the northern section e g the zhuji dingji pansan and panbei mines is the largest energy base in eastern china to investigate the mineralogical and geochemical responses of coal to igneous intrusion minerals major and trace elements in sandstone thermally altered coal igneous rock sandy mudstone and unaltered coal samples were collected from a representative profile of the no 1 coal of the pansan coal mine the samples were analyzed using an optical microscope powder x ray diffraction scanning electron microscopy in conjunction with x ray energy dispersive spectroscopy x ray fluorescence inductively coupled plasma atomic emission spectrometry and mass spectrometry the results indicated that the thick sill transformed from mafic rocks at the bottom via intermediate rocks in the middle to felsic rocks at the top of the profile the moisture total sulfur and carbon contents of the coal increased whereas volatile matter hydrogen and nitrogen decreased during contact metamorphism caused by igneous intrusion epigenetic minerals i e dolomite quartz and pyrite occurred in the thermally altered coals three stages of hydrothermal fluids i e ca mg and fe rich si rich and fe and or h2s rich solutions were identified iron ca s si mg zn cd and pb were transported into the thermally altered coal by hydrothermal fluids the concentrations of co and ni in the thermally altered coal increased in relation to the increase of ash yields that were caused by contact metamorphism whereas the b in the coal was volatilized manganese is directly related to the intrusive magma phosphorus ge and sr might be introduced into the coal by groundwater however k na ga and ba were leached out titanium sc cr v cu zr nb and rare earth elements and yttrium rey in the coals originated from terrigenous input and were not influenced by igneous intrusion

riverine particulate organic carbon from an active mountain belt importance of landslides 1 we investigate the routing and transfer of particulate organic carbon poc from the western southern alps new zealand using organic carbon corg and nitrogen norg concentrations and stable carbon isotopes 13corg in this active mountain belt sediment discharge is dominated by landslide derived material landsliding acts to homogenize the geochemically diverse hillslope poc mixing poc from the standing biomass and soil with the fossil poc from bedrock as a result the poc in river sediment at the mountain front is a binary mixture of fossil and nonfossil carbon sourced from many landslide deposits we calculate that nonfossil biogenic poc makes up 63 7 of the total poc in the suspended load of rivers draining the western southern alps the erosional flux of biogenic poc from these catchments represents a transfer of 39 tc km 2 a 1 of atmospheric co2 averaged over the west flank of the mountain belt if more than 10 of this poc is preserved in sediments on geological timescales then this process is the most significant way in which the southern alps and similar tectonically active mountain belts with restricted alluvial aprons consume atmospheric co2

distribution of arsenic in coals of yunnan province china and its controlling factors abstract the as concentration and its distribution patterns in southwestern chinese coal beds of two of the most important coal forming periods late permian and neogene are analyzed more than 700 samples from 26 mining districts have been collected and tested for as concentration the as content and distribution in coal can be significantly changed by the combined effects of many factors including the geochemistry of the source region and the tectonic and depositional environment of the basin and surrounding paleo watershed the as distribution in neogene coals of yunnan province reflects to some extent their primary distribution patterns during peat accumulation because as is a sulphophile element two as distribution types can be distinguished based on the correlation coefficient between as and total s contents in the high rank permian coals especially those affected by hydrothermal and tectonic activities significant secondary as enrichment in coal is likely to occur thus to optimally utilize coal resources it is important to investigate the distribution occurrence and concentration of as in coal during resource exploration and evaluation to identify as rich zones in the coal beds

concentrations and origins of platinum group elements in late paleozoic coals of china the platinum group elements pges in 63 samples collected from the late paleozoic coal bearing strata in western guizhou province and north china were determined using high resolution inductively coupled plasma mass spectrometry hr icp ms the study shows that pges in coal have five different sources magmatic hydrothermal inputs low temperature hydrothermal fluids synsedimentary volcanic ash detrital minerals of terrigenous origin and seawater this study indicates that the first three sources can lead to enrichment of pges in these chinese coals the typical low contents of pges in most of the studied coals defined as background contents in this work mainly originate from detrital minerals the background content of pd 150 ng g is higher than that of pt 30 ng g and much higher than that of ru 5 ng g rh 14 ng g and ir 1 ng g the pd content is nearly 15 fold higher than the crustal abundance in contrast pt content is lower than its crustal abundance the relatively good correlation between pd pt and ash contents suggests that the pges are associated with minerals

platinum group element mineralization in a hydrothermal cu ni sulfide occurrence rathbun lake northeastern ontario pt pd and au are concentrated in a hydrothermal cu ni sulfide occurrence near rathbun lake northeastern ontario the mineralization is associated with a sheared zone of the wanapitei intrusion where hydrothermal fluids have altered relatively pristine gabbronorite to chlorite sericite quartz epidote and biotite chalcopyrite and pyrite the principal sulfide minerals occur as massive and disseminated mineralization bismuthian merenskyite and to a lesser extent kotulskite michenerite and temagamite are the pd bearing minerals whereas pt occurs primarily in sperrylite 64 percent of the pd mineral grains are associated with altered silicates rather than sulfides although grains within sulfides may have been exsolved the size and number associated with silicates suggest many were precipitated independently grab samples average 9 percent cu 0 2 percent ni 20 829 ppb pd 9 736 ppb pt and 3 053 ppb au values for the other platinum group elements are near background levels no correlation is evident between cu and the platinum group elements or au the ratio of pt pd os ir ru is much larger than for tholeiitic hosted deposits of magmatic origin and probably reflects the relative solubilities of the platinum group elements

a paleomagnetic study of tectonically deformed red beds of the lower glarus nappe complex eastern switzerland a paleomagnetic study at 15 sites 315 samples in permo triassic red beds of the helvetic nappes of eastern switzerland isolated stable characteristic and secondary remanent directions thermal demagnetization and isothermal remanent magnetization experiments suggest pigmentary hematite carries the characteristic direction secondary directions are scattered but may have been acquired during the alpine deformation in the oligocene and miocene the characteristic directions also show large between site scatter anisotropy of magnetic susceptibility indicates that the hematite grains are flattened within the slaty cleavage and that there is a north south lineation this anisotropy pattern implies that the magnetic grains were realigned by the alpine deformation it is not possible to explain the characteristic remanent magnetization deviations on a site by site basis but the site mean directions are streaked along a great circle the down dip direction of which is approximately parallel to the regional fold axes 60 20 this spread could be explained by a penetrative simple shear deformation associated with the nappe internal deformation

experimental strain of isothermal remanent magnetization in ductile sandstone abstract a macroscopically ductile sandstone to which a homogeneous isothermal remanent magnetization irm was applied has been deformed at 150 mpa confining pressure and constant strain rate of 10 5 s 1 hydrostatic compaction does not produce a deflection of the irm vector although it is reduced in intensity pure shear producing shortening in the range 2 to 35 steadily reduces the intensity of magnetization but also homogeneously rotates the remanence vector toward the plane of flattening the amount of rotation is slightly less than that expected for a non material line undergoing homogeneous strain deformation selectively removes weakly coercive components of remanence as revealed by alternating field af demagnetization during deformation a weak deformational viscous remanent magnetization dvrm is acquired from the pressure vessel this is different from a conventional viscous remanent magnetization vrm in that it is not acquired when the specimen is subject to hydrostatic confining pressure alone even for periods three times longer than the longest deformation test

trace element geochemistry of altered volcanic ash layers tonsteins in late permian coal bearing formations of eastern yunnan and western guizhou provinces china trace element compositions were determined by instrumental neutron activation analysis inaa in 30 samples of synsedimentary volcanic ash derived tonsteins and detrital claystones from coal seams within the late permian coal bearing formation of eastern yunnan and western guizhou provinces china the characteristics of trace element geochemistry in the tonsteins can be distinguished from those of detrital claystones because of the former s unique volcanic ash origin the detrital claystones are characterized by their relatively high content of v ti sc cr co and ni relatively low content of th and u th u ratio and small negative eu anomaly eu eu 0 63 0 93 overall these trace element characteristics are consistent with a mafic source similar to the composition of basalt rocks in the erosional region on the western edge of the study area in contrast the tonsteins are low in v ti sc cr co and ni contents and have a high th u ratio with a distinct negative eu anomaly eu eu normally in the range of 0 2 0 4 consistent with a silicic magmatic source within the group of tonsteins those from the lower section p2 1 of the coal bearing formation are relatively high in ti zr hf nb ta and rare earth elements ree as compared to those from the middle and upper sections p2 2 3 in trace element discrimination diagrams scatter plots of hf ta ti ta ti v hf sc lu hf and lu th tonsteins from the p2 1 horizon always fall in isolated distribution areas separate from the tonsteins of the p2 2 3 horizon these results suggest that the source materials of tonsteins from the two separate horizons were probably derived from volcanic ash falls of two distinctly different natures based on a comparison of the concentrations and assemblages of trace elements between various magmatic rocks the source materials of tonsteins from p2 1 horizon were mostly composed of calc alkalic silica poor volcanic ash similar to rhyodacitic magma whereas those from p2 2 3 were apparently more siliceous and k rich rhyolitic magma thus tonsteins from the two different horizons are characterized by unique geochemical properties which remain constant over a wide lateral extent integration of trace elemental compositions with mineralogical and textural observations makes possible the establishment of tonstein stratigraphy thus facilitating more precise and reliable coal seam correlations

episodic wood loading in a mountainous neotropical watershed abstract the upper rio chagres drains 414 km2 of steep mountainous terrain in central panama a tropical air mass thunderstorm on 10 july 2007 produced a flood across the basin that peaked at 720 m3 s 1 at a headwaters gage draining 17 5 km2 and 1710 m3 s 1 at a downstream gage draining 414 km2 the storm also triggered numerous landslides in the upper basin which facilitated the formation of large logjams along portions of the channel where transport capacity of wood was reduced by a change in channel geometry such as a bend or channel expansion during field work in february 2008 we characterized three jams with surface areas of 400 2450 m2 two of these jams resulted in storage of substantial 1100 8200 m3 sediment wedges upstream we returned to these sites in march 2009 to document changes in the logjams and sediment storage drawing on observations made in the basin since 2002 and site visits during 2008 and 2009 we suggest that jams such as these last two years or less we propose that wood dynamics in the upper chagres alternate between brief periods of moderate wood load in the form of large logjams and much longer periods of essentially no wood load a situation that contrasts with the more consistent wood loads in catchments of similar size in temperate environments and with limited studies of more consistent wood load in tropical catchments with no landslides

properties of small instream wood as a logjam clogging agent implications for clogging dynamics based on wood density water content and depositional environment abstract in cooperation with large instream wood lw within logjams small instream wood sw can control downstream flux of sediment and particulate organic matter and can play an important role for stream ecosystems however information regarding the density and moisture content of sw which affects wood transport wood decay and mass loading is limited here we investigated the sw properties i e density under field conditions in situ density basic density volumetric water content and depositional environment of sw sampled from five logjams and their backwater areas in two headwater streams second and third order streams surrounded by mixed broadleaf conifer forests in western japan the in situ density ranged from 0 49 to 1 25 g cm 3 and pieces with densities 1 0 g cm 3 accounted for 45 of all samples additionally the in situ density of sw closely related to the volumetric water content r2 0 76 rather than the basic density as an index of solidity or decay condition of wood the sw that was partially submerged in water had a higher volumetric water content than sw exposed to air these results indicate that a nonfloating transport cannot be ignored as an important mechanism for sw movement and that in situ density depends not on the solidity of the wood but on water sorption by sw however waterlogged sw should be well decayed because it has a lower basic density than air exposed and sediment buried sw we conclude that the moisture conditions of the depositional environment can affect subsequent transport and decay processes of sw moreover most waterlogged and sediment buried sw because of its high in situ density 1 0 g cm 3 may contribute to clogging between the channel bed and lw that initiate a logjam during future movements

the effects of grain scale deformation on the bloomsburg formation pole previous paleomagnetic results from the silurian bloomsburg formation in the central appalachian valley and ridge province suggest that the bloomsburg s characteristic magnetization is a synfolding magnetization acquired during the acadian orogeny however there is little geological evidence to support extensive acadian folding in the central appalachians a more favorable explanation is that the characteristic magnetization originated as a prefolding silurian magnetization and has been altered by grain scale deformation to mimic a synfolding devonian remagnetization in order to investigate whether penetrative deformation has altered the bloomsburg formation s characteristic signal the relationship between strain and remanence was examined around three central appalachian valley and ridge folds structural analysis of mesoscopic and microscopic features along with center to center finite strain analysis at these three folds indicates a deformation sequence that includes prefolding layer parallel shortening overprinted by top to the foreland bedding parallel shear and flexural slip flow folding inclination of the characteristic magnetization varies systematically with the magnitude of finite strains this relationship between strain and remanence suggests that the characteristic magnetization has been progressively rotated toward shallower inclinations by penetrative deformation analogous to rigid particle rotation in a viscously deforming matrix using directions from sites with relatively low finite strain values a new bloomsburg formation pole is calculated at 18 7 n 107 4 e k 58 4 a95 8 2 this new pole falls on the silurian track of the north american apparent polar wander path between the silurian wabash reef pole and the silurian devonian andreas pole in addition these results suggest that previously reported 20 30 difference in declination of site mean directions north arid south of the pennsylvania salient may also be the result of grain scale reorientation of the remanence carrying grains and not oroclinal bending

geomorphologic controls on the age of particulate organic carbon from small mountainous and upland rivers 1 to assess the role that erosion processes play in governing the character of particulate organic carbon poc discharged from small mountainous and upland rivers a suite of watersheds from oregon california and new zealand was investigated the rivers share similar geology tectonic setting and climate but have sediment yields that range over 3 orders of magnitude the 14c age of the poc loads is highly correlated with sediment yield carbon isotope mass balances reveal that the rivers carry bimodal mixtures of modern plant and ancient rock derived oc at lower yields modern plant oc dominates the material delivered to the river by sheetwash and shallow landsliding with increasing yield a progressively larger part of the poc is contributed directly from bedrock erosion via deep gully incision our results support the inference that active margin watersheds are important sources of aged poc to the ocean

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

terrestrial sedimentation and the carbon cycle coupling weathering and erosion to carbon burial this paper examines the linkages between the carbon cycle and sedimentary processes on land available data suggest that sedimentation on land can bury vast quantities of organic carbon roughly 1015 g c yr 1 to evaluate the relative roles of various classes of processes in the burial of carbon on land terrestrial sedimentation was modeled as a series of 864 scenarios each scenario represents a unique choice of intensities for seven classes of processes and two different global wetland distributions comparison was made with presumed preagricultural conditions the classes of processes were divided into two major component parts clastic sedimentation of soil derived carbon and organic sedimentation of autochthonous carbon for clastic sedimentation masses of sediment were considered for burial as reservoir sediment lake sediment and combined colluvium alluvium and aeolian deposits when the ensemble of models is examined the human induced burial of 0 6 1 5 1015 g yr 1 of carbon on land is entirely plausible this sink reaches its maximum strength between 30 and 50 n paddy lands stand out as a type of land use that warrants future study but the many faces of rice agriculture limit generalization in an extreme scenario paddy lands alone could be made to bury about 1 1015 g c yr 1 arguing that terrestrial sedimentation processes could be much of the sink for the so called missing carbon is reasonable such a hypothesis however requires major redesign of how the carbon cycle is modeled unlike ecosystem processes that are amenable to satellite monitoring and parallel modeling many aspects of terrestrial sedimentation are hidden from space

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

climate regulates the erosional carbon export from the terrestrial biosphere erosion drives the export of particulate organic carbon from the terrestrial biosphere pocbiosphere and its delivery to rivers the carbon transfer is globally significant and can result in drawdown of atmospheric carbon dioxide co2 if the eroded pocbiosphere escapes degradation during river transfer and sedimentary deposition despite this recognition we lack a global perspective on how the tectonic and climatic factors which govern physical erosion regulate pocbiosphere discharge obscuring linkages between mountain building climate and co2 drawdown to fill this deficit geochemical 13c 14c and c n hydrometric water discharge suspended sediment concentration and geomorphic slope measurements are combined from 33 globally distributed forested mountain catchments radiocarbon activity is used to account for rock derived organic carbon and reveals that pocbiosphere eroded from mountain forests is mostly 1300 14c years old annual pocbiosphere yields are positively correlated with suspended sediment yields confirming results from taiwan and a recent global analysis and are high in catchments with the steepest slopes based on these relationships and the global distribution of slope angles 3 arc second it is suggested that topography steeper than 10 16 of the continental area may contribute 40 of global pocbiosphere erosional flux climate is shown to regulate pocbiosphere discharge by mountain rivers by controlling hydrologically driven erosion processes in catchments where discharge measurements are available 8 of the 33 a significant relationship exists between daily runoff mm day 1 and pocbiosphere concentration mg l 1 r 0 53 p 0 0001 the relationship can be described by a single power law and suggests a high connectivity between forested hillslopes and mountain river channels as a result annual pocbiosphere yields are significantly correlated with mean annual runoff r 0 64 p 0 0001 a shear stress pocbiosphere erosion model is proposed which can explain the patterns in the data the model allows the climate sensitivity of this carbon flux to be assessed for the first time for a 1 increase in annual runoff pocbiosphere discharge is predicted to increase by 4 in steeper catchments pocbiosphere discharge increases more rapidly with an increase in annual runoff for comparison a 1 increase in annual runoff is predicted to increase carbon transfers by silicate weathering solute fluxes in mountains by 0 4 0 7 depending on the fate of the eroded pocbiosphere river export of pocbiosphere from mountains may act as an important negative feedback on rising atmospheric co2 and increased global temperature erosion of carbon from the terrestrial biosphere links mountain building and climate to the geological evolution of atmospheric co2 while the carbon fluxes are sensitive to predicted changes in runoff over the coming century

natural streams and the legacy of water powered mills gravel bedded streams are thought to have a characteristic meandering form bordered by a self formed fine grained floodplain this ideal guides a multibillion dollar stream restoration industry we have mapped and dated many of the deposits along mid atlantic streams that formed the basis for this widely accepted model these data as well as historical maps and records show instead that before european settlement the streams were small anabranching channels within extensive vegetated wetlands that accumulated little sediment but stored substantial organic carbon subsequently 1 to 5 meters of slackwater sedimentation behind tens of thousands of 17th to 19th century milldams buried the presettlement wetlands with fine sediment these findings show that most floodplains along mid atlantic streams are actually fill terraces and historically incised channels are not natural archetypes for meandering streams

trace element abundances in major minerals of late permian coals from southwestern guizhou province china abstract fourteen samples of minerals were separated by handpicking from late permian coals in southwestern guizhou province china these 14 minerals were nodular pyrite massive recrystallized pyrite pyrite deposited from low temperature hydrothermal fluid and from ground water clay minerals and calcite deposited from low temperature hydrothermal fluid and from ground water the mineralogy elemental composition and distribution of 33 elements in these samples were studied by optical microscopy scanning electron microscope equipped with energy dispersive x ray spectrometer sem edx x ray diffraction xrd cold vapor atomic absorption spectrometry cv aas atomic fluorescence spectrometry afs inductively coupled plasma mass spectrometry icp ms and ion selective electrode ise the results show that various minerals in coal contain variable amounts of trace elements clay minerals have high concentrations of ba be cs f ga nb rb th u and zr quartz has little contribution to the concentration of trace elements in bulk coal arsenic mn and sr are in high concentrations in calcite pyrite has high concentrations of as cd hg mo sb se tl and zn different genetic types of calcite in coal can accumulate different trace elements for example ba co cr hg ni rb sn sr and zn are in higher concentrations in calcite deposited from low temperature hydrothermal fluid than in that deposited from ground water furthermore the concentrations of some trace elements are quite variable in pyrite different genetic types of pyrites py a b c d have different concentrations of trace elements and the concentrations of trace elements are also different in pyrite of low temperature hydrothermal origin collected from different locations the study shows that elemental concentration is rather uniform in a pyrite vein there are many micron and submicron mosaic pyrites in a pyrite vein which is enriched in some trace elements such as as and mo the content of trace element in pyrite vein depends upon the content of mosaic pyrite and of trace elements in it many environmentally sensitive trace elements are mainly contained in the minerals in coal and hence the physical coal cleaning techniques can remove minerals from coal and decrease the emissions of potentially hazardous trace elements

the transfer of modern organic carbon by landslide activity in tropical montane ecosystems 1 geomorphic processes play an important role in the transfer and storage of carbon within steep mountainous terrain among these mass wasting stands out because of its impact on above and below ground carbon pools and its potential for releasing or sequestering carbon a combined remote sensing and gis modeling approach was used to quantify the amount and spatial redistribution of modern organic carbon mobilized by mass wasting activity in a tropical mountain setting the study focused on a population of hundreds of shallow translational landslides triggered by hurricane mitch 1998 on seven watersheds draining the southern flank of the sierra de las minas mountain range slm in central eastern guatemala results illustrate that mass wasting contributed to the transfer of 43 104mgc or 3 of the pre event c in above ground vegetation and soils for an equivalent carbon flux rate of 0 08 0 33 mgc ha 1 y 1 depending on whether we consider hurricane mitch to be a landslide triggering event with a 20 year or an 80 year recurrence interval while 30 of this carbon was delivered to hillslopes or first order streams with a presumed high potential for long term sequestration the remaining 70 was delivered to higher order streams with unknown carbon retention capabilities therefore the ultimate fate of the carbon released by landsliding is very uncertain but depending on the proportion sequestered by colluvial deposits the recurrence interval of landslide triggering events and the rate of ecosystem recuperation at the landslide failure sites mass wasting could be either a net source or sink of carbon in a simulated setting based on the slm study results in which all carbon transferred by landslides from all tropical mountains of the globe is released to the atmosphere it would represent an amount equivalent to 1 11 of the global carbon currently being released by the burning of fossil fuels meanwhile in a projected scenario where a significant proportion of the carbon transferred by landslides is retained within sedimentary deposits sequestration rates would equal 2 19 of the residual land sink

revisiting platinum group elements of late permian coals from western guizhou province sw china twenty five coal samples from the late permian coal bearing strata in weining nayong and zhijin western guizhou province sw china were analyzed for platinum group elements pges the coal ashes were digested by the carius tube technique and accurately measured by isotope dilution inductively coupled plasma mass spectrometry id icp ms for all pges the results are much lower than the previous reported values our study suggested that the previously reported pge values are incorrect and may due to the polyatomic interferences in icp ms measurements in our study samples from the weining coalfield have the lowest pge contents from 0 019 ir to 0 42 ng g pd which represent the pge background value in coal in western guizhou province some of the coals have pt and pd contents about 20 times higher than the background value indicating pges are concentrated we also reported new and reliable pge data and background value of coal in western guizhou province sw china and suggested to rework the pge background values of chinese coals

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

late cretaceous coal overlying karstic bauxite deposits in the parnassus ghiona unit central greece coal characteristics and depositional environment abstract the pera lakkos coal located on top of bauxite deposits in the ghiona mining district central greece is the only known mesozoic late cretaceous coal in the country it was derived from herbaceous plants and algae growing in mildly brackish mires that formed behind a barrier system during a regression of the sea on a karstified limestone partly filled in with bauxitic detritus petrological mineralogical and geochemical data point to the predominance of reducing conditions and intense organic matter degradation in the palaeomires o c vs h c and oi vs hi plots based on elemental analysis and rock eval data characterize kerogen types i ii this reflects the relatively high liptinite content of the coal besides kerogen composition o c vs h c plot for the pera lakkos coals is in accordance with a catagenesis stage of maturation in contrast with vitrinite reflectance and t max from rock eval pyrolysis which indicate the onset of oil window maturation stage suppression of vitrinite reflectance should be considered and the high liptinite content corroborates this hypothesis despite some favourable aspects for petroleum generation presented by the pera lakkos coal its maximum thickness up to 50 cm points to a restricted potential for petroleum generation coal oxidation took place either during the late stage of peat formation due to wave action accompanying the subsequent marine transgression or epigenetically after the emergence of the whole sequence due to percolation of drainage waters both options are also supported by the ree shale normalized profiles which demonstrate an upwards depletion in the coal layer oxidation also affected pyrite included in the coal this led to the formation of acidic sulfate rich solutions which percolated downwards resulting in bleaching of the upper part of the underlying bauxite

iridium and palladium as discriminants of volcanic exhalative hydrothermal and magmatic nickel sulfide mineralization neutron activation of pd au and ir in samples from 1 economically significant ni sulfide deposits of western australia 2 the host rocks of these deposits 3 hydrothermal and or metasomatic ni sulfide mainly millerite mineralization in peridotite at nullagine western australia 4 hydrothermal replacement volcanic exhalative ni cu sulfide mineralization at sherlock bay western australia and 5 volcanic exhalative sulfides in inter flow sediments at kambalda are used to show that ir and pd can be used to discriminate between the various origins magmatic volcanic exhalative hydrothermal metasomatic and metamorphic ascribed to ni sulfide deposits all the economically significant ni sulfide deposits in western australia are strongly enriched in the precious metals relative to other crustal rocks and have similar pd ni and ir ni ratios to each other these ratios persist regardless of whether the nickel sulfides occur at the base of volcanic ultramafic piles e g kambalda or as centrally disposed interstitial sulfides in intrusive dunite bodies the strong similarities of the pd ir ratios of the ni sulfide ores and of the spinilex textured komatiites which represent ultramafic liquids from which the ni sulfide liquids were derived together with other features of the precious metal geochemistry of the ores and host rocks of the ni sulfide deposits are used to show that the deposits had magmatic origins in contrast the pd ir and ir ni ratios of the hydrothermal and or metasomatic ni sulfide mineralization at nullagine are distinctly different from those of the major ni deposits the former contains high au moderate but variable pd and exceptionally low ir similarly the volcanic exhalative sulfides at kambalda and sherlock bay contain negligible quantities of pd and ir all the ir in both the interflow sediments and the hydrothermal metasomatic mineralization is contributed by the host rocks and not by the sulfides the western australian data together with precious metal data for other examples of hydrothermal ni cu sulfide mineralization strongly suggest that although ni au and pd may be transported in aqueous solution ir cannot hence the relative abundance of ir can be used as a discriminant of magmatic sulfides

preferred orientation developed by rigid markers in two dimensional simple shear strain a theoretical and experimental study abstract in a homogeneous two dimensional deformation linear markers embedded in a viscous matrix develop a preferred orientation along the principal axis of the strain ellipse theoretical analysis of marker rotation under two dimensional simple shear is used to derive an orientation distribution function this function shows that the relative density maximum increases with progressive strain its value being equal to the major minor strain ellipse axis ratio moreover the density is equal to the unity along the lines of no finite longitudinal strain experimentally observed preferred orientation is in good agreement with the expected theoretical distribution

organic carbon export in the form of wood during an extreme tropical storm upper rio chagres panama widespread intense rainfall over the upper rio chagres watershed 414 km2 in central panama during december 2010 triggered numerous landslides that introduced large numbers of trees to the river network we flew by helicopter along the mainstem upper chagres and the adjacent margins of lake alhajuela into which the upper chagres flows in february and june 2011 we used low elevation video photography from these flights to tally the number of wood pieces stored along the lake margin and within the channel and the number of landslides reaching the mainstem we used these tallies with ground verified estimates of average wood piece size and landslide surface area and assumptions about wood density carbon content and aboveground biomass to develop a first order estimate of carbon export in the form of wood from the upper chagres following the 2010 storms based on the wood tally we estimate 9 6 to 16 mg c km2 export and from the landslide tally we estimate 24 mg c km2 we believe the landslide tally provides a more accurate minimum estimate of carbon export from the upper chagres during the december 2010 storms these values are an order of magnitude higher than limited data for average or background rates of wood based carbon export from other catchments but two orders of magnitude lower than wood based carbon export during extreme storms in taiwan the findings suggest that duration of flood flow above a threshold for mobilizing wood within the channel network exerts a more important control on wood export from the upper chagres than magnitude of flood peak copyright 2013 john wiley sons ltd

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