weathering and the mobility of phosphorus in the catchments and forefields of the rhone and oberaar glaciers central switzerland implications for the global phosphorus cycle on glacial interglacial timescales abstract in this study we evaluate the dynamics of the biophile element phosphorus p in the catchment and proglacial areas of the rhone and oberaar glaciers central switzerland we analysed erosion and dissolution rates of p containing minerals in the subglacial environment by sampling water and suspended sediment in glacier outlets during three ablation and two accumulation seasons we also quantified biogeochemical weathering rates of detrital p in proglacial sedimentary deposits using two chronosequences of samples of fresh suspended material obtained from the oberaar and rhone water outlets little ice age lia moraines and younger dryas yd tills in each catchment subglacial p weathering is mainly a physical process and detrital p represents more than 99 of the precipitation corrected total p denudation flux 234 and 540 kg km 2 yr 1 for the rhone and oberaar catchments respectively the calculated detrital p flux rates are three to almost five times higher than the world average flux the precipitation corrected soluble reactive p srp flux corresponds to 1 88 1 99 kg km 2 yr 1 rhone and 2 12 2 44 kg km 2 yr 1 oberaar respectively these fluxes are comparable to those of tropical rivers draining transport limited tectonically inactive weathering areas in order to evaluate the efficiency of detrital p weathering in the rhone and oberaar proglacial areas we systematically graded apatite grains extracted from the chronosequence in each catchment relative to weathering induced changes in their surface morphologies grades 1 4 fresh apatite grains are heavily indented and dissolution rounded grade 1 lia grains from two 0 10 cm deep moraine samples show extensive dissolution etching similar to surface grains from the yd profile mean grades 2 7 3 5 and 3 5 respectively in these proglacial deposits the weathering front deepens progressively as a function of time due to biocorrosion in the evolving acidic pedosphere with mechanical indentations on grains acting as sites of preferential dissolution we also measured iron bound organic and detrital p concentrations in the chronosequence and show that organic and iron bound p has almost completely replaced detrital p in the top layers of the yd profiles detrital p weathering rates are calculated as 310 and 280 kg km 2 yr 1 for lia moraines and 10 kg km 2 yr 1 for yd tills during the first 300 years of glacial sediment exposure p dissolution rates are shown to be approximately 70 times higher than the mean global dissolved p flux from ice free continents after 11 6 kyr the flux is 2 5 times the global mean these data strengthen the argument for substantial changes in the global dissolved p flux on glacial interglacial timescales a crude extrapolation from the data described here suggests that the global dissolved p flux may increase by 40 45 during the first few hundred years of a deglaciation phase

is late quaternary climate change governed by self sustained oscillations in atmospheric co2 a simple earth system model is developed to simulate global carbon and phosphorus cycling over the late quaternary it is focused on the geological cycling of c and p via continental weathering volcanic and metamorphic degassing hydrothermal processes and burial at the seabed a simple ocean model is embedded in this geological model where the global ocean is represented by surface water thermocline and deep water boxes concentrations of dissolved phosphorus dissolved inorganic carbon and total alkalinity are calculated for each box the partial pressure of co2 in the atmosphere pco 2a is determined by exchange processes with the surface ocean and the continents it serves as key prognostic model variable and is assumed to govern surface temperatures and global sea level the model is formulated as autonomous system in which the governing equations have no explicit time dependence for certain parameter values the model does not converge towards a steady state but develops stable self sustained oscillations these free oscillations feature pco 2a minima and maxima consistent with the ice core record when vertical mixing in the ocean is allowed to vary in response to pco 2a controlled temperature change a stable 100 kyr cycle with a rapid transition from glacial to interglacial conditions is obtained when additional non linear equations are applied to calculate deep ocean mixing iron fertilization and the depth of organic matter degradation as function of pco 2a controlled surface temperature the delta c 13 value of carbon in the ocean atmosphere system calculated in these model runs is consistent with the benthic delta c 13 record however the simulated c 13 depletion in the glacial ocean is not driven by the decline in terrestrial carbon stocks but by sea level change controlling the rates of organic carbon burial and weathering at continental margins the pco 2a and delta c 13 oscillations develop without any form of external milankovitch forcing they are induced and maintained by sea level change generating persistent imbalances in the marine carbon and phosphorus budgets stable oscillations are also obtained when sea level change is allowed to lag temperature with a realistic time scale for ice sheet adjustment

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

petrophysical and microfacies analysis as a tool for reservoir rock typing and modeling rudeis formation off shore october oil field sinai abstract petrographically the lower miocene rudeis reservoir rock samples in october oil field can be summed up into three reservoir rock types rrts the rrt1 samples are mostly calcareous to ferruginated sandstones sometimes are fossiliferous whereas the rrt2 and rrt3 samples are carbonate rocks of grainstone and packstone microfacies respectively cementation by sparite and compaction are the most important porosity reducing diagenetic factors whereas dissolution and leaching out as well as fracturing are the most dominant porosity enhancing factors the petrophysical and reservoir quality studies include measuring density porosity permeability measurements as well as reservoir quality index rqi flow zone indicator fzi and reservoir potential index rpi calculations the permeability porosity plot is the key factor for discriminating the petrophysical behaviour into these three rock reservoir types petrophysically the studied sandstone rrt1 samples have the best storage capacity and reservoir quality the rqi fzi and the rpi indicate poor to very good reservoir quality whereas the rrt3 samples have the least prospective properties the rqi fzi and the rpi indicates impervious reservoir quality based on the fzi values the studied rudeis formation was discriminated into a number of hydraulic flow units 6 hfus hfu 5 6 are the best reservoir zones they are assigned in the central parts of the studied area whereas the least quality hfu 1 3 was assigned to the south in addition the mercury injection capillary pressure tests micp indicates that the rrt1 samples are ranked as iv fair to vi impervious ranks the rrt2 as v poor to vi whereas the rrt3 samples are impervious samples wettability of the studied rrt1 samples is mostly neutral

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

step drawdown test as a tool for the assessment of the nubia sandstone aquifer in east el oweinat area egypt the cretaceous nubia sandstone aquifer is the main aquifer in east el oweinat area along the egyptian sudanese borders and in ne africa east el oweinat project has been recently considered one of the main agricultural projects in the southwest of the egyptian western desert so the hydrogeological assessment for the nubia aquifer in east el oweinat area has been done through studying and characterising the hydraulic parameters and step drawdown test the well and aquifer losses coefficients c and b respectively the specific capacity and the well efficiency as well as the aquifer and aquitard thickness have been estimated and traced through a total of 46 wells that have been distributed through the study area in two sectors southern and northern for the purpose of further exploration the effective porosity hydraulic conductivity k and transmissivity t have been estimated for the wells in the northern sector in addition an aquifer assessment quality index has been introduced to assess and to rank the studied aquifer therefore it is concluded that the hydraulic and the step draw down parameters as well as the aquifer and aquitard thicknesses are prospective for further exploration to the north and the east of the northern sector in the study area the well efficiency is mostly affected by the studied parameters particularly the well loss coefficient the hydraulic parameters and the well design as well gis approach and arcgis software have been applied to delineate the spatial distribution of the well performance characteristics in order to compare between the studied groundwater wells and to integrate the different acquired data a set of isocontour maps have been introduced to match the lateral variation of the studied parameters and the aquifer potential to refer to the best direction for further underground water exploration

petrophysical and magnetic pore network anisotropy of some cretaceous sandstone from tushka basin egypt summary pore magnetic fabric is a well established technique for the determination of pore elongation and preferred directions for migration of the interstitial fluids this study further exemplify this technique on a set of the nubia sandstones through a comparison with the pore anisotropy obtained from measuring permeability in three orthogonal directions in a gaz permeameter the nubia sandstones are represented in tushka area south egypt by quartz arenite of large porosity 29 40 per cent which was measured on thin sections parallel and perpendicular to the bedding plane and petrophysically by helium pycnometry and ferrofluid injection at 1 bar pressure petrographically there is a detectable difference between the porosity values in the bedding plane and in the perpendicular direction indicating inhomogeneity in the pore space network distribution the petrophysical studies indicate large porosity and permeability values with some differences between the helium and ferrofluid porosity due to presence of micro pore spaces not accessible for the ferrofluid molecules having relatively high diameters and injected at low pressure an overall agreement is observed between the permeability anisotropy and the magnetic grain and pore fabrics magnetic anisotropy measured before and after ferrofluid injection the three fabrics are mainly dominated by a bedding parallel foliation in a few cases maximum permeability appears to be perpendicular to bedding within the bedding plane maximum pore elongation direction from ferrofluid injection is nnw for adindan and kesieba formations and nw for abu simbil formation the maximum pore elongation direction for abu ballas samples showed a direction fluctuating around the e w direction the main fault trends in tushka area the pore fabric of abu ballas formation seems therefore to be structurally controlled while it would be originated from palaeocurrent directions in the other formations

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

determining the porosity exponent m and lithology factor a for sandstones and their control by overburden pressure a case study from the gulf of suez egypt the porosity exponent m represents an important parameter in archie s equation it is routinely used in well logging interpretation and formation evaluation it reflects some petrophysical rock properties such as the petrofabrics pore fabrics and overburden pressure obp data measured at ambient conditions for a total of 55 sandstone core samples were obtained from 8 wells varying in depositional facies geologic age degree of consolidation and cementation material and then measured again at obp similar to the actual reservoir conditions to check the effect of obp on archie s parameters and to introduce a model of high reliability other published data sets were also used to confirm the study results based on the best fit regression analysis several empirical relationships were introduced to relate the porosity exponent to pore volume lithology factor and permeability the effect of obp on the porosity exponent was also investigated in relation to the petrophysical parameters given the above a new statistical model is proposed to relate the porosity exponent to the permeability of the studied sandstone samples in the gulf of suez egypt the effect of confining pressure on the studied porosity exponent m and the lithology factor a is significant when porosity is less than or equal to 10 from the present study categorization of the studied samples into flow units and rock types using the hydraulic flow unit and the discrete rock types increased the reliability of the obtained relationships and increased the applicability of the obtained equations in addition the value of the lithology factor a fluctuates around 1 0 92 1 04 regardless of the applied processing method whereas the value of the porosity exponent m fluctuates around 1 83 the obtained relationships between the formation resistivity factor and porosity have a very high reliability 0 949 correlation coefficient 0 969

dissolved inorganic phosphorus export to the coastal zone results from a spatially explicit global model 1 here we describe test and apply a spatially explicit global model of river borne dissolved inorganic phosphorus dip export called news dip among the innovations in news dip are increased spatial resolution 0 5 0 5 explicit treatment of sewage fertilizer manure and weathering p sources and inclusion of reservoir retention and consumptive water use terms the news dip model performed better than pre existing global models in predicting dip yield for both calibration and validation basins r2 0 72 and 0 56 respectively news dip predicts that of the 34 tg of p yr 1 loaded on watersheds by human activity globally approximately 3 reaches river mouths as dip anthropogenic sources account for 65 0 71 tg yr 1 of the dip exported to the coastal zone with the remainder 0 38 tg yr 1 attributable to natural weathering processes dip yields range over 5 orders of magnitude from less than 0 01 to 1153 kg p km 2 yr 1 with highest predicted dip yields clustering in east asia europe and indonesia human sewage is the largest anthropogenic source of dip to the coastal zone on all continents and to all ocean basins news dip also suggests that despite regional variability at the global scale non point sources of dip such as inorganic p fertilizer and manure are much less important in determining coastal export of dip than point sources and natural weathering processes

simulating the biogeochemical effects of volcanic co2 degassing on the oxygen state of the deep ocean during the cenomanian turonian anoxic event oae2 cretaceous anoxic events may have been triggered by massive volcanic co2 degassing as large igneous provinces lips were emplaced on the seafloor here we present a comprehensive modeling study to decipher the marine biogeochemical consequences of enhanced volcanic co2 emissions a biogeochemical box model has been developed for transient model runs with time dependent volcanic co2 forcing the box model considers continental weathering processes marine export production degradation processes in the water column the rain of particles to the seafloor benthic fluxes of dissolved species across the seabed and burial of particulates in marine sediments the ocean is represented by twenty seven boxes to estimate horizontal and vertical fluxes between boxes a coupled ocean atmosphere general circulation model aogcm is run to derive the circulation patterns of the global ocean under late cretaceous boundary conditions the aogcm modeling predicts a strong thermohaline circulation and intense ventilation in the late cretaceous oceans under high pco2 values with an appropriate choice of parameter values such as the continental input of phosphorus the model produces ocean anoxia at low to mid latitudes and changes in marine 13c that are consistent with geological data such as the well established 13c curve the spread of anoxia is supported by an increase in riverine phosphorus fluxes under high pco2 and a decrease in phosphorus burial efficiency in marine sediments under low oxygen conditions in ambient bottom waters here we suggest that an additional mechanism might contribute to anoxia an increase in the c p ratio of marine plankton which is induced by high pco2 values according to our aogcm model results an intensively ventilated cretaceous ocean turns anoxic only if the c p ratio of marine organic particles exported into the deep ocean is allowed to increase under high pco2 conditions being aware of the uncertainties such as diagenesis this modeling study implies that potential changes in redfield ratios might be a strong feedback mechanism to attain ocean anoxia via enhanced co2 emissions the formation of c enriched marine organic matter may also explain the frequent occurrence of global anoxia during other geological periods characterized by high pco2 values

occurrence and origin of minerals in a chamosite bearing coal of late permian age zhaotong yunnan china the minerals found in the no 5 coal late permian from the zhaotong coalfield yunnan province southwestern china have been examined and found to consist mainly of kaolinite pyrite chamosite quartz and calcite with trace amounts of illite and mixed layer illite smectite the proportion of chamosite in clay minerals ranges from 32 to 56 wt with an average of 46 wt chamosite is distributed not only in collodetrinite but also occurs as cell fillings in fusinite semifusinite and telinite the high content and mode of occurrence of chamosite in this mine indicate its formation by interaction of kaolinite with fe mg rich fluids during early diagenesis except for a minor amount of terrigenous quartz most quartz is of authigenic origin and formed from kaolinite desilication the calcite content of the no 5 coal is 1 4 6 3 with an average of 3 and is distributed in collodetrinite and as cell fillings of coal forming plants calcite originated from seawater invasion during peat accumulation pyrite occurs in several ways as massive framboidal isolated enhedral anhedral and euhedral forms in addition the presence of a large amount of pyritized red algae provides strong evidence of seawater invasion during peat accumulation the red algae may have played an important role in the enrichment of sulfur in the coal the characteristic assemblage of minerals in this mine resulted from a unique basinal environment in which the mineral matter was derived from a basaltic source region volcanic activity and seawater transgression during coal formation

distribution isotopic variation and origin of sulfur in coals in the wuda coalfield inner mongolia china abstract this paper describes coal petrographic characteristics sulfur abundance distribution and isotopic signature in coals in the wuda coalfield inner mongolia northern china petrographic studies suggest that depositional environment influences petrographic composition the no 9 and no 10 coal seams which are thought to have formed on a tidal delta plain have high collodetrinite contents up to 66 1 indicating enhanced gelification and bacteria activity during coal accumulation and also have the highest sulfur content 3 46 and 3 42 both organic and pyritic sulfur isotope values 12 3 to 5 8 and 18 7 to 1 1 respectively are variable and generally tend to be more negative in high sulfur coals than those in low sulfur coals in the wuda coalfield the negative sulfur isotope values indicate that a large portion of sulfur in the high sulfur coals has a bacterial origin sulfur isotopic compositions and variations within the section were used to propose a model to explain the origin of sulfur in these coals the presence of pyritized rod like bacteria cyanophyte s gelatinous sheaths and degraded algae organic matter suggests that bacteria and perhaps algae may play an important role in the formation of these high sulfur coals

origin and distribution of tonsteins in late permian coal seams of southwestern china abstract we have surveyed the areal and stratigraphic distribution of tonsteins in late permian coalfields of southwestern china over an area of several hundred thousand square kilometers we studied the relationship between tonstein distribution and sedimentary environment based on mineralogical and petrographic data we have concluded that these tonsteins originated as air fall volcanic ashes following accumulation in the peat swamps in situ alteration of the vitric and lithic components took place under acidic conditions leading to the formation of kaolinite based on petrologic mineralogic and chemical analytical data we have determined that the application of mineralogic and geochemical criteria for tonsteins may be useful in correlating coal beds predicting coal qualities and reconstructing related sedimentary paleoenvironmental conditions

geological controls on the mineral matter and trace elements of coals from the fuxin basin liaoning province northeast china abstract this study summarizes the results of geological petrographical geochemical and mineralogical studies performed to determine the geological controls on coal quality of the fuxin deposit liaoning province in northeast china the study is focused on the haizhou mine which currently mines a coal bearing clastic lower cretaceous series affected by a diabase intrusion three major coal seams are differentiated the taiping the middle and the shunjawan fuxin coal is a high quality coal with low ash and sulphur contents 4 0 to 18 0 hta and 0 3 to 0 8 s tot and high calorific value 5600 to 7500 cal g as received basis coal impurities both major and trace elements are at very low concentrations only a high mn concentration up to 8600 ppm was detected the rank of fuxin coal mainly high volatile b bituminous coal is clearly influenced by the diabase intrusion which has induced the formation of natural coke from coal natural coke surrounds the diabase dykes and sills with a thickness ranging from a few centimetres up to 1 5 m in addition a wide aureole made up of high volatile a bituminous coal formed around the coke the diabase intrusion was not a major source of elemental mobilization mn being the only element clearly enriched in the coal by 1 to 2 orders of magnitude however major changes in major and trace element distribution affinities were induced in the coal by the intrusion the geochemical study revealed that these changes were the consequence of the mobilization of organic sulphide and carbonate associated elements

ree geochemistry of the cretaceous lignite from wulantuga germanium deposit inner mongolia northeastern china abstract the wulantuga germanium deposit wgd hosted in coal seams with ge resources up to 1600 mt is located in the shengli coalfield in xilingol inner mongolia china forty two channel samples of ge bearing lignites of the no 6 1 coal seam lower cretaceous bayanhua formation were collected and their ree compositions were analyzed by inductively coupled plasma mass spectrometry icp ms the modes of occurrence of ree in selected lignite samples were studied by scanning electron microscope with energy dispersive x ray spectrometer sem edx and statistical methods the distribution of ree and y in all 42 samples from wgd are in accordance with the log normal distribution the total rare earth element content ree of most lignite samples from wgd range from 9 02 to 118 ppm only four samples show relatively higher 149 533 ppm ree concentration the average ree contents of 42 lignite samples from wgd are slightly higher than those of the usa coals world wide coals sandstone from wgd and the contemporary ge barren lignite from hongqi coal mine the lignite samples from wgd have shale like chondrite or nasc normalized ree patterns similar to those of sandstone overburden and ge barren lignite from hongqi coal mine ree contents of most lignite samples are highly positive correlated with ash yields indicating a mainly detrital source and association with syngenetic mineral matter ree rich phosphates monazite were identified by sem edx in some medium to high ash ash yields range from 23 58 to 38 18 lignite samples with high ree y contents from wgd ree can be concentrated in the upper and lower proportions of the no 6 1 coal seam the vertical profiles of ree mainly follow that of tio 2 and the average ree tio 2 ratio of lignite sample in three sections is very close to that of the sandstone from wgd or lignite from hongqi coal mine it was determined that most ree in the lignite from wgd were derived from a detrital source and associated with syngenetic mineral matter however when normalized to the overlying sandstone some lignite samples from wgd display a small but distinct enrichment in middle to heavy ree indicating small quantity of middle to heavy ree may be added and or retained during epigenesis the lignite samples from wgd are characterized by higher ratios of lree hree and eu eu and horizontal nasc normalized ree patterns and distinguished from those of the ge bearing lignites from lincang germanium deposit yunnan china and ge deposits of russian far east there is no distinct correlations between ge and any individual ree or ree y content of lignite from wgd

determination of electrofacies using wireline logs based on multivariate statistical analysis for the kareem formation gulf of suez egypt beyond the traditional use of well logs electrofacies were introduced to define a set of log responses that can be used to characterize a bed and permitted it to be distinguished from the other rock units classification of a formation into electrofacies can be used in reservoir characterization and discrimination due to the hydrocarbon potential of the kareem formation we used the conventional well logs of four boreholes and a traditional core analyses data from one of these wells to identify electrofacies of the kareem formation in the southern gulf of suez multivariate statistical analyses such as principal component analysis pca and cluster analysis were used for this purpose the multivariate statistical analyses were applied to the raw log data the normalized data and the standardized log data three pc components were obtained from the analyses and six distinctive electrofacies were extracted from the dendrogram plot these electrofacies showed good correlation with the lithofacies that were described from core analysis in addition applying the reservoir zonation of the studied formation using the stratigraphic modified lorenz sml plot and the sum of squared errors sse methods led to its discrimination into four hydraulic flow units the deduced flow units were validated against the available core data

geomorphometric attributes of the global system of rivers at 30 minute spatial resolution in this paper we explore the geomorphometric characteristics and integrity of a 30 0 longitude latitude spatial resolution representation of the global system of potentially flowing rivers we quantify several geomorphometric attributes of digital simulated topological network stn 30p depicting potential flow pathways across the entire non glacierized surface of the earth this data set was examined with respect to several metrics describing individual grid cells river segments and complete drainage systems nearly 60 000 grid cells constitute the global non glacierized land mass the cells are organized into more than 30 000 distinct river segments belonging to approximately 6200 drainage basins stn 30p flow paths and drainage basins are classified as order one through six using the classification system of strahler stn 30p flow pathways depict rivers draining a global land area of 133 1 10 6 km 2 these pathways show a total length of 3 24 10 6 km at 30 0 spatial resolution the relationships between stn 30p order and interior river segment numbers accumulated sub basin areas and accumulated length within individual basins yield high correlation coefficients average r 2 0 96 for continents and globe mean values across individual continents and river orders for the bifurcation ratio 3 15 to 4 44 drainage area ratio 3 74 to 5 77 and basin length ratio 2 02 to 3 27 fall well within the ranges tabulated at finer spatial scales a basin shape index sba l a 0 5 defined as a function of potential mainstem length and drainage area varies between 1 0 and 5 0 for basins 25 000 km 2 and shows a global mean of 2 12 the structure of stn 30p potential river systems is consistent with those of rivers analyzed at finer spatial scales as demonstrated by the numerical similarity of the several geomorphometric indices analyzed however for a particular basin indices from stn 30p will be based on a condensed set of river orders relative to those derived at finer scales a first order stn 30p river is roughly equivalent to an order five to six river derived from 1 62 500 scale maps while 30 0 spatial resolution was found to represent well the 522 basins with areas 25 000 km 2 that drain 82 of the land mass it cannot be used with high confidence in characterizing the geomorphometry of the remaining smaller basins for global climate and biogeochemical studies a composite of the 30 0 resolution and finer spatial resolutions appears to be necessary q 2000 elsevier

global system of rivers its role in organizing continental land mass and defining land to ocean linkages the spatial organization of the earth s land mass is analyzed using a simulated topological network stn 30p representing potential flow pathways across the entire nonglacierized surface of the globe at 30 min longitude latitude spatial resolution we discuss a semiautomated procedure to develop this topology combining digital elevation models and manual network editing stn 30p was verified against several independent sources including map products and drainage basin statistics although we found substantial inconsistency within the extant literature itself a broad suite of diagnostics is offered that quantitatively describes individual grid cells river segments and complete drainage systems spanning orders 1 through 6 based on the strahler classification scheme continental and global scale summaries of key stn 30p attributes are given summaries are also presented which distinguish basins that potentially deliver discharge to an ocean exorheic from those that potentially empty into an internal receiving body endorheic a total of 59 122 individual grid cells constitutes the global nonglacierized land mass at 30 min spatial resolution the cells are organized into 33 251 distinct river segments which define 6152 drainage basins a global total of 133 1 106 km2 bear stn sop flow paths with a total length of 3 24 106 km the organization of river networks has an important role in linking land mass to ocean from a continental perspective low order river segments orders 1 3 drain the largest fraction of land 90 and thus constitute a primary source area for runoff and constituents from an oceanic perspective however the small number n 101 of large drainage systems orders 4 6 predominates draining 65 of global land area and subsuming a large fraction of the otherwise spatially remote low order rivers along river corridors only 10 of land mass is within 100 km of a coastline 25 is within 250 km and 50 is within 750 km the global mean distance to river mouth is 1050 km with individual continental values from 460 to 1340 km the mediterranean black sea and arctic ocean are the most land dominated of all oceans with land ocean area ratios of 4 4 and 1 2 respectively remaining oceans show ratios from 0 55 to 0 13 we discuss limitations of the stn 30p together with its potential role in future global change studies stn 30p is geographically linked to several hundred river discharge and chemistry monitoring stations to provide a framework for calibrating and validating macroscale hydrology and biogeochemical flux models

quality parameters of lignite of the north bohemian basin in the czech republic in comparison with the world average lignite abstract sulfur is considered to be the most harmful element in atmospheric emissions and fall out which originate from coal combustion total sulfur content std in lignites of the north bohemian basin nbb has a geometric mean of 1 61 wt at n 12 979 and is mostly influenced by the presence of iron disulfides the distribution of sulfur and many trace elements is log normal a non uniform distribution of sulfur in lignite was found within the basin with the lowest std contents i e not exceeding 1 wt s confined to the eastern and southeastern margin of the nbb contents between 1 and 1 5 wt s are most common in lignites of the south central nbb lower sulfur contents were identified in the area of the atec delta and its northern extension in contrast high contents of sulfur in lignite exceeding 1 5 wt are found along the northern margin of the basin at the foot of the krusne hory mts and in the westernmost part of the nbb three genetically different types of iron disulfides occur in lignite of the nbb synsedimentary early diagenetic diagenetic and epigenetic among those forms synsedimentary disulfides mostly pyrite appear to be most abundant they form finely dispersed microscopic framboids or veinlets that commonly parallel the coal bedding the other iron disulfide forms are much less abundant dissolved sulfate which was supplied to the nbb during the miocene is likely to have been derived from sulfides of the krusne hory mts crystalline complex this unit has an isotopic composition of sulfide sulfur varying between 1 and 5 consequently the sulfate supplying the nbb should exhibit slightly positive 34 s values syngenetic pyrites forming microframboids or veinlets in coal show 34 s values close to 0 these values are similar those of sulfur dioxide in gases of power stations burning nbb coal this implies that no considerable shifts in sulfur isotopic composition occur during thermal oxidation of the dominant pyrite arsenic is positively correlated with sulfur r2 0 89 its total content astd is 20 53 ppm at n 9172

reservoir zonation rock typing and compartmentalization of the tortonian serravallian sequence temsah gas field offshore nile delta egypt abstract the present study aims to evaluate the petrophysical properties and to discriminate the tortonian wakar and the serravallian sidi salem formations in the offshore temsah gas field north egypt into distinctive rock types the measured conventional core data includes helium and summation fluids porosities grain and bulk densities horizontal and vertical permeabilities as well as the water saturation also the reservoir quality index rqi flow zone indicator fzi and reservoir potentiality index rpi were calculated to establish a successful reservoir zonation in the temsah field the tortonian serravallian sequence has been discriminated into four reservoir rock types rrts which are described based on its lithologic composition as 1 sandy to argillaceous carbonates rrt1 2 siliceous pebbly sandstones rrt2 and 3 argillaceous to calcareous sandstones rrt3 and 4 calcareous to dolomitic sandstones rrt4 based on the petrophysical interpretation and ranking for the studied samples samples of rrt2 have very good rank due to presence of very good porosity excellent permeability and good to very good rqi and fzi values which are assigned as the best reservoir rock type in the tortonian serravallian sequence the petrophysical behavior of rrt4 shows the lowest reservoir quality impervious rqi and poor fzi the examined sequence has been sliced into reservoir zones each zone has its hydraulic flow unit range that represents the studied rock types in each zone based on the applied pressure tools including repeat formation tester rft and the modular formation dynamic tester mdt both the wakar and sidi salem reservoirs represent completely isolated compartments therefore ranking both reservoirs and estimating their hydrocarbon potential must be done separately for each reservoir

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

groundwater potential for irrigation in the east oweinat area western desert egypt the nubia sandstone aquifer system is one of the most extensive groundwater systems in north africa covering an area of about 2 000 000 km2 including parts of egypt libya sudan and chad in the western desert of egypt the nubian formation has a thermal gradient of 1 1 5 c 100 m 1 with the exception of the east oweinat area located in the southern part of the western desert this is the only part of this huge system where ground water occurs under unconfmed conditions in an area where the nubian sandstone crops out and is underlain by shallow basement rocks in this area groundwater has no thermal characteristics the aquifer system in the east oweinat area attains a relatively high hydraulic conductivity the direction of groundwater flow is generally northeastwards but is distorted at faults and fracture zones chemical analyses of groundwater in the area indicate a low salt content and suitability for irrigation purposes as the estimated recharge to the area is low compared with the foreseen irrigation water requirement the development of groundwater in the east oweinat should be based on groundwater mining although the evaluation of the groundwater resources in east oweinat has indicated that groundwater can be extracted at a rate of 4 7 106 m3 d 1 the long term economics of extraction that can sustain large scale development projects has to be assessed

sedimentary rock hosted au deposits of the dian qian gui area guizhou and yunnan provinces and guangxi district china abstract sedimentary rock hosted au deposits in the dian qian gui area in southwest china are hosted in paleozoic and early mesozoic sedimentary rocks along the southwest margin of the yangtze south china precambrian craton most deposits have characteristics similar to carlin type au deposits and are spatially associated on a regional scale with deposits of coal sb barite as tl and hg sedimentary rock hosted au deposits are disseminated stratabound and or structurally controlled the deposits have many similar characteristics particularly mineralogy geochemistry host rock and structural control most deposits are associated with structural domes stratabound breccia bodies unconformity surfaces or intense brittle ductile deformation zones such as the youjiang fault system typical characteristics include impure carbonate rock or calcareous and carbonaceous host rock that contains disseminated pyrite marcasite and arsenopyrite usually with m sized au commonly in as rich rims of pyrite and in disseminations late realgar orpiment stibnite and hg minerals are spatially associated with earlier forming sulfide minerals minor base metal sulfides such as galena sphalerite chalcopyrite and pb sb as sulphosalts also are present the rocks locally are silicified and altered to sericite clay illite rocks and or stream sediment geochemical signatures typically include elevated concentrations of as sb hg tl and ba a general lack of igneous rocks in the dian qian gui area implies non pluton related ore forming processes some deposits contain evidence that sources of the metal may have originated in carbonaceous parts of the sedimentary pile or other sedimentary or volcanic horizons this genetic process may be associated with formation and mobilization of petroleum and hg in the region and may also be related to as au and tl bearing coal horizons many deposits also contain textures and features indicative of strong structural control by tectonic domes or shear zones and also suggest syndeformational ore deposition possibly related to the youjiang fault system several sedimentary rock hosted au deposits in the dian qian gui area also are of the red earth type and au grades have been concentrated and enhanced during episodes of deep weathering

forms and availability of sediment phosphorus in carbonate sand of bermuda seagrass beds primary production by seagrasscs in tropical and subtropical carbonate sediments often appears to be phosphorus p limited and several studies have sought to identify the possible sources of p for long term growth here we quantify concentrations of particulate and dissolved p and fluoride f in carbonate sediments sediment water p exchange and leaf tissue p concentrations in three seagrass beds in bermuda we also present data on the sequential extraction of p and f from the sediments at each site total sediment p tp in the upper 20 cm ranged from 650 to 1 250 mmol p m 2 and was some 500 fold larger than the pool of p dissolved in pore waters loosely adsorbed inorganic p comprised 2 of tpsed while a surface bound inorganic p pool extracted by dithionite buffer constituted 15 20 most of the remaining p and nearly all of the ca and f present in the sediment was recovered when the remaing sediment was dissolved in an acetic acid buffer solution this pool includes calcium fluoroapatite cfa which is considered the primary diagenetic sink for p in carbonate sands dissolved inorganic p and fwere both elevated in the rhizosphere pore waters from the three seagrass beds in combination with our analysis of sediments by sequential extraction this result indicates that the carbonate matrix of the sediment is being dissolved in the rhizosphere with a resulting release of p to the pore water and hence to the seagrass roots we suggest that this is important in the p economy of these subtropical seagrass thalussia testudinum beds and note that the carbonate bound p pool is large enough to sustain seagrass p requirements for decades nonetheless primary production in such seagrass systems can remain p limited if the rate of p release from sediment dissolution is too slow to support maximum seagrass growth rates analysis of seagrass leaf tissues revealed that p availability was highest at the site with the highest anthropogenic influences this site was also characterized by the highest sediment p release indicating that high p availability may also be partly due to higher release of p as sediments are dissolved phosphorus was released from the sediment mainly as dissolved organic p causing a net efflux of dissolved p at all sites in april and at two sites in august

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

sediment discharge and export of fluvial carbon and nutrients into the arafura and timor seas a regional synthesis abstract the arafura and timor seas ats are a crucial link between the indian and pacific oceans and play a vital role in global ocean circulation and climate some high standing islands in the ats are globally significant sources of sediment here we derive a synthesis of river catchments and their role as sources of water sediment carbon and nutrients to estimate the pathways magnitude and fate of exported riverine materials the edge of the australian continental shelf and slope receives riverine sediment from asia as isotopes suggest a mixing of sediment sources with some overlap between the australian and non australian material including evidence of significant input of volcanic material from indonesia the catchments bordering both the arafura and timor seas account for 12 of sediment and 35 of water discharged from tropical asia northern australia discharges a volume of freshwater comparable to southwest new guinea but 50 65 of total sediment 754 mt dic 61 1 mt poc 7 9 mt doc 3 5 mt tn 2 88 mt and tp 254 264 t delivered annually to the ats come from new guinea the island of timor discharges much smaller amounts of water 170 km 3 yr 1 and sediment 133 mt yr 1 but area specific rates of dic 1150 t km 2 yr 1 poc 238 t km 2 yr 1 doc 94 t km 2 yr 1 tn 61 t km 2 yr 1 and tp 4 4 t km 2 yr 1 are higher reflecting very high rates of deforestation and land degradation compared to other tropical rivers carbon export into the ats is dominated by dic the ats catchments are being increasingly affected by human activities and material discharge to the continental margins will likely increase impacting shelf communities and highly diverse reef mangrove and seagrass habitats

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

tracing river chemistry in space and time dissolved inorganic constituents of the fraser river canada abstract the fraser river basin in southwestern canada bears unique geologic and climatic features which make it an ideal setting for investigating the origins transformations and delivery to the coast of dissolved riverine loads under relatively pristine conditions we present results from sampling campaigns over three years which demonstrate the lithologic and hydrologic controls on fluxes and isotope compositions of major dissolved inorganic runoff constituents dissolved nutrients major and trace elements 87 sr 86 sr d a time series record near the fraser mouth allows us to generate new estimates of discharge weighted concentrations and fluxes and an overall chemical weathering rate of 32 t km 2 y 1 the seasonal variations in dissolved inorganic species are driven by changes in hydrology which vary in timing across the basin the time series record of dissolved 87 sr 86 sr is of particular interest as a consistent shift between higher more radiogenic values during spring and summer and less radiogenic values in fall and winter demonstrates the seasonal variability in source contributions throughout the basin this seasonal shift is also quite large 0 709 0 714 with a discharge weighted annual average of 0 7120 2 s d 0 0003 we present a mixing model which predicts the seasonal evolution of dissolved 87 sr 86 sr based on tributary compositions and water discharge this model highlights the importance of chemical weathering fluxes from the old sedimentary bedrock of headwater drainage regions despite their relatively small contribution to the total water flux

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

electric pore fabric of the nubia sandstones in south egypt characterization and modelling summary this study testifies the reliability of the electric pore fabric technique applied on the nubia sandstones in south egypt through a comparison with pre assigned magnetic pore fabric and permeabilityalreadymeasuredforthreeperpendiculardirectionsintheserocks discrepancies between the different techniques were attributed to the fact that the magnetic pore fabric technique has the ability to detect and define accurately the pore volume distribution in 3 d whereas the electric pore fabric technique has the ability to detect the shortest paths for the electric current fluid flow although the magnetic pore fabric is a bulk property the permeability measurements and the electric pore fabric are quantifying transport properties both the magnetic and electric pore fabrics refer mostly to slightly and moderately anisotropic fabrics the integration between both techniques revealed two main directions for fluid migration swinging to the n s and the e w directions one difficulty of the electric pore fabric technique is due to the surface conductivity effects either from the presence of some clay minerals or cracks therefore interpreting the obtained electric pore fabric must be carried out in care for the cracked and clayey rocks the surface conductivity effect could be accounted for by using the true formation factor for calculating the electric pore fabric parameters the electric pore fabric technique can be compared to the 3 d permeability measurements which show very similar directions

phosphorus imbalance in the global ocean the phosphorus budget of the pre human modern ocean is constrained applying the most recent estimates of the natural riverine eolian and ice rafted input fluxes the phosphorus burial in marine sediments and the hydrothermal removal of dissolved phosphate from the deep ocean this review of current flux estimates indicates that the phosphorus budget of the ocean is unbalanced since the accumulation of phosphorus in marine sediments and altered oceanic crust exceeds the continental input of particulate and dissolved phosphorus the phosphorus mass balance is further tested considering the dissolved phosphate distribution in the deep water column the marine export production of particulate organic matter rain rates of phosphorus to the seafloor benthic dissolved phosphate fluxes and the organic carbon to phosphorus ratios in marine particles these independent data confirm that the phosphate and phosphorus budgets were not at steadystate in the pre human global ocean the ocean is losing dissolved phosphate at a rate of 11 6 x 1010 mol yr 1 corresponding to a decline in the phosphate inventory of 4 5 kyr 1 benthic data show that phosphate is preferentially retained in pelagic deep sea sediments where extended oxygen exposure times favor the degradation of particulate organic matter and the up take of phosphate in manganese and iron oxides and hydroxides enhanced c p regeneration ratios observed in the deep water column 400 m water depth probably reflect the preferential burial of phosphorus in pelagic sediments excess phosphate is released from continental margin sediments deposited in low oxygen environments the dissolved oxygen threshold value for the enhanced release of dissolved phosphate is 20 m benthic phosphate fluxes increase drastically when oxygen concentrations fall below this value

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

long term controls on ocean phosphorus and oxygen in a global biogeochemical model 1 in this study we use a biogeochemical ocean general circulation model hamocc originally developed for the carbon and silicon cycles and expand it with a description of the sedimentary phosphorus p cycle the model simulates the release of reactive p by aerobic and anaerobic degradation of organic matter in the sediment as well as formation and burial of fe oxide bound p and authigenic ca p minerals we also include pre anthropogenic inputs of p from atmospheric dust which is mostly in the form of detrital apatite model predicted total p concentrations and rates of reactive p burial for the deep sea agree reasonably well with observations in open ocean and near continental margin sediments as part of a sensitivity analysis we assess the long term response of ocean productivity and deep water oxygenation to increases in the riverine input of p and preferential release of p from sediments the simulations show that the feedback from preferential p regeneration accelerates the expansion of suboxia o2 2 5mm along continental margins and in the naturally suboxic areas in tropical subtropical regions on timescales of 10 100 ka for a case in which maximum p regeneration from sediments is enabled a large scale pattern of bottom water suboxia 30 of the total ocean area develops over the southeastern tropical and northern pacific ocean sectors

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

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

mineralogy and geochemistry of boehmite rich coals new insights from the haerwusu surface mine jungar coalfield inner mongolia china abstract boehmite rich coal of pennsylvanian age was discovered earlier at the heidaigou surface mine jungar coalfield inner mongolia china this paper reports new results on 29 bench samples of the no 6 coal from a drill core from the adjacent haerwusu surface mine and provides new insights into the origin of the minerals and elements present the results show that the proportion of inertinite in the no 6 coal is higher than in other late paleozoic coals in northern china based on mineral proportions boehmite to kaolinite ratio and major element concentrations in the coal benches of the drill core the no 6 coal may be divided into five sections i to v major minerals in sections i and v are kaolinite sections ii and iv are mainly kaolinite with a trace of boehmite and section iii is high in boehmite the boehmite is derived from bauxite in the weathered surface benxi formation in the sediment source region the no 6 coal is rich in al2o3 8 89 tio2 0 47 li 116 g g f 286 g g ga 18 g g se 6 1 g g sr 350 g g zr 268 g g rees 172 g g pb 30 g g and th 17 g g the elements are classified into five associations by cluster analysis i e groups a b c d and e group a ash sio2 al2o3 na2o li and group b ree sc in y k2o rb zr hf cs u p2o5 sr ba ge are strongly correlated with ash yield and mainly have an inorganic affinity the elements that are negatively or less strongly correlated with ash yield with exceptions of fe2o3 be v and ni are grouped in the remaining three associations group c se pb hg th tio2 bi nb ta cd sn group d co mo tl be ni sb mgo re ga w zn v cr f cu and group e s as cao mno fe2o3 aluminum is mainly distributed in boehmite followed by kaolinite the high correlation coefficients of the li ash li al2o3 and li sio2 pairs indicate that li is related to the aluminosilicates in the coal the boehmite rich coal is high in gallium and f which occur in boehmite and the organic matter selenium and pb are mainly in epigenetic clausthalite fillings in fractures the abundant rare earth elements in the coal benches were supplied from two sources the bauxite on the weathered surface of the benxi formation and from adjacent partings by groundwater leaching during diagenesis the light rare earth elements lrees are more easily leached from the partings and incorporated into the organic matter than the heavy rees leading to a higher ratio of lrees to hrees in the coal benches than in the overlying partings