occurrence distribution and probable source of the trace elements in ghugus coals wardha valley districts chandrapur and yeotmal maharashtra india abstract trace element determinations of 15 coal samples have been made in order to know their distribution behaviour and associations with the organic and inorganic fractions in the coal the coal samples have been systematically collected in stratigraphic sequences so that the vertical variation of the trace elements can be studied the elements determined by spectographic analysis are w v cr sc y cu co pb be ni and ba the results indicate that the concentration of trace elements in these coals varies greatly from bottom to top sections the elements v and co are extremely poor in the top and middle sections whereas in the bottom section they are fairly distributed be is extremely poor in the bottom section and fairly distributed in the middle and top sections w sc y have poor concentration in the bottom section as compared to the middle and top sections ni is fairly distributed in the bottom section whereas its concentration is poor in the middle and top sections cr and cu are fairly distributed in the bottom middle and top sections ba has unusually high concentration in all the sections it appears from the present study that w cr sc y and be are concentrated more in silicate minerals clay quartz etc associated with coal and the elements like co and ni have intimate relation with organic matters in coal and are present as organometallic compounds as well as absorbed cations cu and pb which are present in the coals are derived from the inorganic matter mainly from the pyrites whereas w has affinity with carbonate minerals in the coals the ba is mainly associated with the inoraanic matter of coal its unusually high concentration indicates association with carbonates clays and other silicate minerals

numerical simulation of m2 internal tides in the south brazil bight and their interaction with the brazil current 1 a fully three dimensional nonlinear primitive equation ocean model is applied to study the semidiurnal internal tide in the south brazil bight under summer conditions along the shelf break and upper slope of this region the upper layer 0 600 m is occupied by the southward flowing brazil current several numerical experiments were conducted to investigate the generation and propagation of the m2 internal tide using horizontally homogeneous and vertically stratified density fields internal tides were generated over the whole bight with a clear signal on the continental shelf when a more realistic summer stratification was considered a baroclinic jet representative of the brazil current developed and comparisons between current observations and modeled results were improved this jet acts as a barrier to the coastward propagation of the internal tide generated over the slope reflecting it back towards the open ocean on the negative relative vorticity side of the brazil current located over the shelf internal tides are trapped enhancing vertical current variability and hence tidally induced mixing the results highlight the importance of considering background flows when investigating internal tides in regions of strong along slope baroclinic flows such as western boundary currents

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

first report of cisuralian early permian charcoal layers within a coal bed from baode north china with reference to global wildfire distribution abstract fossil charcoal is reported for the first time from a cisuralian coal bed of the shanxi formation in the qiaotou section baode shanxi north china based on anatomical characteristics these charcoal fragments consist of coniferous or cordaitalean xylem unidentified primary xylem and cordaitalean and possible fern leaves these charcoal fragments represent the evidence of palaeowildfire taking place in tropical peat swamps during the cisuralian in cathaysia the palaeowildfire is most likely to be a surface fire and burning litter and shrubby vegetation fire frequency for this early permian peat swamp might have been on the order of 176 294 588 1429 years close to modern values compared with modern analogues the north china block during the cisuralian was probably wet in general but could be occasionally seasonally dry for short time intervals previous charcoal and inertinite records moreover indicate that palaeowildfires were globally common during the cisuralian overall more wildfire evidence was found in the artinskian kungurian than the asselian sakmarian except in the euramerican realm probably due to more suitable regional climate vegetation to fuel fires and taphonomic circumstances

trace elements and their variation along seam profiles of certain coal seams of middle and upper barakar formations lower permian in east bokaro coalfield district hazaribagh bihar india abstract trace element data are presented for the first time for any coal seam in india across a full working section based on systematically collected channel samples of coal together with their maceral composition the trace element variation curves along the seam profile are presented together with group maceral compositions of kargali bottom kargali top kargali kathara uchitdih jarangdih bottom jarangdih and jarangdih top seams east bokaro coalfield the kathara and uchitdih seams have also been sampled at two other localities and lateral variation in data in their trace element and maceral compositions is also evaluated the east bokaro coals have ba and sr 1000 ppm mn the trend of the variation patterns and average compositions of the different seams are shown to be distinct and different the variation along the same profile is inferred to be different for different seams of the coalfield trace element data for certain coals of seams from different coalfields in the gondwana basins of india are presented there is a wide difference for each of these basins with respect to certain elements this is suggestive of the proportions of cu ni v y ba sr cr b zr and ag characterizing the different gondwana basins

influence of a cold water bottom dome on internal wave trapping 1 a numerical model of a cross section through a cold water bottom dome is used to examine the influence of wind forcing frequency dome length and density field upon the variability of internal waves in the region forcing at super inertial frequencies produces internal waves in the frontal regions that propagate into the centre of the dome producing a standing wave the wavelength of the internal wave depends upon water depth forcing frequency and stratification at the edges of the dome internal waves are trapped by the bottom fronts at sub inertial forcing waves are trapped close to the dome s boundary giving different mixing to that found with super inertial forcing these calculations suggest significant differences in internal wave spectra in domes compared with open sea observations these spectral differences would be a critical test of the model s dynamics

petrography and rank of the bhangtar coals southeastern bhutan in bhutan a potential coal deposit is exposed at bhangtar in the landslide zone nineteen coal seams are encountered in this area and occur in the lower gondwana supergroup preserved in between the main boundary fault and the thrust the coal is low in moisture 1 76 but the coal cores show moisture values of 3 16 the ash content is up to 48 87 and increases substantially in the younger seams the volatile content on a pure coal basis ranges from 23 38 to 41 02 the sulphur content is less than 0 61 the coals are non coking the amount of trace elements in the coal is quite low the average petrographic composition of the bhangtar coal is vitrinite 31 exinite 2 inertinite 31 and mineral and shaly matter 36 the vitrinite proportion decreases from the older to the younger seams which are shaly vitrinite telinite is derived mainly from cordaitalean wood and is fractured or unfractured showing an oil reflectance rm range of 0 71 0 72 and 0 54 0 60 respectively the oil reflectance variation is governed by a similar variation in the volatiles of the coal exinite is mainly sporinite and cutinite and is constituted of organic matter from upper permian mioflora so that a late permian age can be assigned to the bhangtar coal based on oil reflectance the rank of the coal is metalignitous to hypobituminous the average microlithotype composition of the coal is vitrite 30 clarite 1 vitrinertite v 14 vitrinertite i 11 durite 3 fusite 14 and carbominerite 27 vitrite decreases in proportion towards the younger seams intermediates show a concomitant increase while durite and fusite remain constant carbonaceous shale contains fragmentary inertinite and vitrinite macerals and is interlayered with micro bands of shaly coal which is characterised by abundant fragments of fusinite and vitrinite the coal is very fragile and thus amenable to economic beneficiation the removal of carbonaceous shale in this process increases the vitrinite content thereby reducing the inertinite the coal is used as fuel in electric power plants the petrographic composition of the bhangtar coal has been compared with those of the upper and lower permian coals of the gondwana coalfields of peninsular india the bhangtar coal is characteristically distinct from the gondwana coals of india in petrography and rank but correlates petrographically with the kameng coals of arunachal pradesh india

geochemistry of trace elements of tertiary coals of india abstract forty one coal samples from seven tertiary basins of the himalayas representing coalfields of the states of assam sub bituminous meghalaya lignitous to sub bituminous and jammu and kashmir low volatile bituminous to semi anthracite have been spectrographically analyzed the trace elements analyzed were ge ni co cu pb mo zr mn cr ba ga v sr b nb sn la and y there are differences in trace element concentrations between the eocene coals of northeastern and northwestern india a significant difference also exists between the eocene and oligocene coals of northeastern india the results show that some of the elements are significant for the identification and correlation of the coal seams the element cr can be used as a marker or index element for the oligocene coals of the makum and dilli jeypore coalfields of northeastern india and mn for the ecocene coals of meghalaya of northeastern india the interpretation of organic inorganic association of the trace elements indicates that elements such as ni co ba v sr cr y ge and nb are associated with the organic fractions pb and cu show affinity with both the organic matter and sulphides mn shows affinity with the organic matter and mineral matter while ga is exclusively related to the mineral matter further it has been revealed that the eocene and oligocene coals of northeastern india originated under marine conditions in contrast the eocene coals of northwestern india give significant evidence of a high influx of fresh water during coal development and show parity with the fluviolacustrine coals of lower gondwana so far as the concentrations of the trace elements are concerned

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

petrology and chemistry of permian coals from the parana basin 1 santa terezinha leao butia and candiota coalfields rio grande do sul brazil the current paper presents results on petrological and geochemical coal seam characterization in permian coal bearing strata from the parana basin southern brazil sequence stratigraphic analysis shows that peat accumulation in permian time was closely linked to transgressive regressive cycles with peat accumulation occurring in a predominantly back barrier lagoonal setting coal petrographic analysis indicates subbituminous coals at candiota and leao butia and high volatile bituminous coals at santa terezinha where locally the coal seams are thermally altered by volcanic intrusions petrographic composition is highly variable with seams at candiota and santa terezinha frequently enriched in inertinite chemical analyses indicate that all coals are mineral matter rich mean 49 09 wt with sio2 and al2o3 dominating as determined by icp aes quartz is also the predominant mineral detected by x ray diffraction where it is associated with feldspar kaolinite and hematite and iron rich carbonates the results from scanning electron microscopy are broadly consistent with the bulk chemical and mineralogical analysis quartz and clays are common in all samples analyzed other minerals observed were amongst others carbonates calcite siderite ankerite pyrite monazite kaolinite barite sphalerite rutile and quartz of volcanic origin the distribution of trace elements is well within the range typical for coal basins of other areas despite the fact that the parana basin coals are very high in ash yields the average concentrations for elements of environmental concern as b be cd co cr cu hg li mn mo ni pb sb se tl u v zn are similar to or less than the mean values for u s coal however considered on an equal energy basis parana basin coals will produce in combustion 5 to 10 times the amount of most elements compared to an equal weight us coal concentrations of major and trace elements such as fe b and s appear to be controlled by depositional setting with increasing values in coal seams overlain by brackish marine strata hierarchical cluster analysis identified three groups of major minerals and seven groups of trace elements based on similarity levels on a regional scale the coalfields can be separated by the differences in rank candiota and leao butia versus santa terezinha and by applying discriminant analysis based on 4 trace elements li as sr sb highest rb and sr values occur at candiota and are linked to syngenetic volcanism of the area whereas high y and sr values at santa terezinha can be related to the frequent diabase intrusions in that area

the stratigraphic distribution of inertinite abstract the paper presents the results of an investigation into the stratigraphic distribution of inertinite in humic coals ranging from the silurian to the neogene periods this range equals the time span during which both land plants and atmospheric oxygen evolved the survey is based on a literature study of inertinite in coals covering a variety of depositional environments and climates in all continents the inertinite percentages listed in this paper have been arranged in stratigraphic order they are the mean values based on mineral free whole coal compilations maceral compositions listed in the literature for individual subsections have been averaged to represent complete coal seams beds although this might not have been always possible due to some ambiguity in the published record moreover not all of the published and unpublished information could be used because of poor sample description obscure geographic origin or insufficient stratigraphic information the results show that there have been times in the geological past e g during the late permian in which coals were particularly rich in inertinite compared with other times e g during much of the late tertiary in which many coals contained very little inertinite occasionally such primary global trends were modulated by a diffuse distribution of inertinite percentages that correspond to differences in climate depositional settings e g active orogenic margins versus tectonically inactive shelf margins and other local or regional variations although various mechanisms for the generation of inertinite have been proposed in the past the overall pattern in its stratigraphic distribution supports the notion of incomplete combustion as the main source of inertinite in coal this points to secular variations in the atmospheric oxygen content as an explanation for the global changes in the inertinite distribution while differential subsidence and climatically influenced reaction rates governed regional and local variations in inertinite percentages

the vertical distribution of minerals in coal zones a b c d hat creek british columbia abstract the four superimposed coal zones a b c d lie in the hat creek graben in folded and faulted eocene strata 76 consecutive samples from ddh 75 106 were analysed by xrd and examined in polished section kaolinite and quartz are the major minerals with kaolinite increasing with depth some upper samples grade into halloysite montmorillonite bentonite is virtually absent illite mostly in zone a varies irregularly with depth appears to be antipathetic to dolomite and between 160 and 306 m to be associated with tonstein pyrite occurs throughout the core only above 358 m is it detected by xrd pyrite and siderite occur in polished section but in xrd appear to be unrelated zone c shows a marked deficiency in mineral varieties cristobalite is found throughout zone a and in the lower half of d major gypsum in the upper part of a and in the lower part of d no correlation exists between minerals and palynomorphs

seasonal evolution of the upwelling process south of cape blanco abstract bursts of upwelling favorable winds lasting 4 20 days occur year round south of cape blanco a major headland on the oregon coast the ocean s response to these events was studied using moored current temperature and salinity data satellite sst data and a few across shelf sections near the mooring site the mooring was located at 42 26 49 n 124 34 47 w 6 n mi off gold beach oregon from may 2000 to october 2003 after the spring transition but before upwelling jet separation equatorward wind stress produced a steady upwelling response much the same as a long straight coast currents and winds had similar spectral characteristics with a peak near 15 days after jet separation upwelling favorable winds forced a much more variable current consisting of a series of thin equatorward jets that evolved and moved offshore across the mooring with shorter time scales than the wind stress forcing during autumn the equatorward wind stress weakened slightly and a transition period occurred with

petrographic chemical and trace elemental composition of the coal of sohagpur coalfield madhya pradesh india abstract the sohagpur coalfield is a remnant of the son valley basin of gondwana deposition and can be subdivided into three major subbasins from west to east rungta amlai kotma and bijuri thick coal seams occur in the barakar formation lower permian and are being worked extensively petrographic reflectance chemical and trace elemental studies on samples of coal representative of the coal seams of the different subbasins have been carried out and the results are presented here petrographically the coals of one subbasin are different from those of another subbasin and are mainly composed of vitrinertite i and vitrinertite v that alternates with fusite vitrite increases in proportion in the coal seams towards the eastern part of the coalfield and sclerotinite occurs in increased proportion in coal seams towards the western part the reflectance in oil ro max varies from 0 50 to 0 58 in the coals of rungta amlai 0 46 0 56 in kotma and 0 53 1 05 in bijuri subbasins chemically the coals belong to type high volatile symbol b 4 of class bituminous the significant trace elements are v 20 400 ppm cu ni co up to 300 ppm mn ba sr zr up to 800 ppm and la up to 1200 ppm the trace elements show a tendency to increase in proportion towards the eastern part of the coalfield to the immediate east of the coalfield lies the chirimiri coalfield of which the compositional characteristics are also presented these data clearly suggest that the coals of the son valley are different from those of the other gondwana basins i e mahanadi godavari and damodar valley basins

combined effects of wind driven upwelling and internal tide on the continental shelf abstract internal tides on the continental shelf can be intermittent as a result of changing hydrographic conditions associated with wind driven upwelling in turn the internal tide can affect transports associated with upwelling to study these processes simulations in an idealized alongshore uniform setup are performed utilizing the hydrostatic regional ocean modeling system roms with conditions corresponding as closely as possible to the central oregon shelf wind only wo tide only to and tide and wind tw solutions are compared utilizing cases with constant upwelling favorable wind stress as well as with time variable observed stress the tide is forced by applying cross shore barotropic flow at the offshore boundary with intensity sufficient to generate an internal tide with horizontal velocity amplitudes near 0 15 m s 1 corresponding to observed levels the internal tide affects the subinertial circulation mostly through the changes in the bottom boundary layer variability re

near surface dynamics of a separated jet in the coastal transition zone off oregon 1 three dimensional circulation in the coastal transition zone ctz off oregon is studied using a 3 km resolution model based on the regional ocean modeling system the study period is spring and summer 2002 when extensive observations were available from the northeastern pacific component of the global ocean ecosystems dynamics project our main focus is on near surface transports particularly in an area off cape blanco where an energetic coastal current is separated in the ctz comparisons with available observations velocities from midshelf moorings surface velocities from high frequency radars satellite sea surface temperature maps along track sea surface height altimetry and seasoar hydrography show that the model reproduces qualitatively correctly the flow structure and variability in the study area the near surface flow behavior during 26 july to 21 august a late summer time period of strong time variable southward winds is examined during that period the coastal jet separates from the continental shelf around cape blanco 43 n the energetic separated jet continues to flow southward in a near coastal region between 42 2 n and 43 n it subsequently turns around 42 n to flow westward offshore past 127 w relatively vigorous up and downwelling is found concentrated in the region of the separated jet frontogenesis secondary circulation nonlinear effects of the relative vorticity on the ageostrophic ekman transport and submesoscale instabilities contribute to the vertical circulation within the jet vertical velocities are found to reach 50 m d 1 in the offshore part of the jet and 100 m d 1 in the near coastal part where the jet is aligned with the wind direction

the burning of gondwana permian fires on the southern continent a palaeobotanical approach abstract fossil charcoal has widely been accepted as a direct indicator for the occurrence of palaeo wildfires in upper palaeozoic sediments of euramerica and cathaysia records of these remains are relatively common and regionally and stratigraphically more or less homogeneously distributed in terrestrial sequences on the other hand just a few records have been published for the permian of gondwana and only recently has it been demonstrated that macroscopic charcoals are also common here most permian macroscopic charcoal from gondwana is gymnospermous and has been reported from coal bearing strata macroscopic charcoal occurrences are spread out in different sequences and also in distinct stratigraphic intervals in the permian e g parana basin sakmarian artinskian of brazil karoo basin artinskian of south africa damodar basin lopingian of india and dead sea area changhsingian of jordan they range from peri glacial post glacial to warm temperate climatic systems throughout the permian macro and micro charcoal occurrences are compared to inertinite incidences to support the pyrogenic origin for these coal macerals and to provide an up to date overview on the known evidences of permian wildfires on gondwana in space and time

a statistical approach to the study of the distribution of trace elements and their organic inorganic affinity in lower gondwana coals of india abstract trace element analyses of seventy six coal samples representing all the major lower gondwana coal basins of india were carried out eighteen trace elements viz b ba co cr cu ga ge la mn mo nb ni pb sn sr v y and zr were determined quantitatively in coal ash an attempt was made to correlate the coals of different coalfields on the basis of multivariate analysis in addition the organic inorganic affinities between the trace elements were established by the coefficients of correlation between the trace elements and ash present a synthesis of the data reveals that there is similarity in the concentration ranges of trace elements among the coal seams of different coalfields but the possibility of environmental differences exists due to the statistically different multivariate means of the trace element concentrations it is inferred that ge cr y and la occur in these coals as organo metallic complexes and chelates the elements ni co ga v and cu show both organic and inorganic association whereas mn and ba are exclusively incorporated in the inorganic fractions

the petrography mineralogy and geochemistry of a paleocene lignite from southern saskatchewan canada abstract the coal petrology mineralogy and elemental composition was determined on the 5 m thick lignite of the estevan seam bienfait mine southwest saskatchewan organic petrology reveals a dominance of huminite macerals 73 with minor liptinite 7 and inertinite 11 macerals the maceral assemblage and the banded nature of the coal suggests a forest moor depositional environment for the lignite optical and scanning electron microscopy and x ray diffraction reveals that the dominant mineralogy of the coal is quartz and carbonates with minor sulfates the roof parting and floor rock are dominated by quartz and clays with minor feldspars elemental concentration is rather uniform with depth most elements are associated with the mineral matter and increase with increasing ash content the elements b na sr and br are associated with the organic portion of the coal some elements show both a mineral and organic association as ba co fe mo ce dy lu w u the high concentrations of certain elements na b ca is attributed to groundwater circulation which can both introduce and remove elements from the porous lignite

trace elements in the goze delchev coal deposit bulgaria abstract the geochemistry of trace elements in the underground and open pit mine of the goze delchev subbituminous coal deposit have been studied the coals in both mines are highly enriched in w ge and be and at less extent in as mn and y as compared with the world wide clarkes for subbituminous coals ni and ti are also enhanced in the underground coals and zr cr and mo in the open pit mine coals characteristic for the trace element contents in the deposit is a regular variation with depth the following patterns were distinguished for profile i a the element content decreases from the bottom to the top of the bed paralleling ash distribution fe co as sb v y mo cs ree hf ta th p and au b ge and w are enriched in the near bottom and near top coals c in the middle part of the bed the content of k and rb is maximal while that of u is slightly enriched d ba content decreases from the top to the bottom of the bed in profile ii w and be contents decrease from the bottom to the top the near bottom and especially the near roof samples of profile iv are highly enriched in ge while for w the highest is the content of the near bottom sample ge be as mn cl and br are mainly organically associated the organic affiliation is still strong for co b sr ba sb u th mo la ce sm tb and yb in the underground coals and fe co na w sr y and ag in the coals from the open pit mine k rb ti zr hf and ta are of dominant inorganic affinity the chalcophile and siderophile elements correlate positively with fe and each other and may be bound partly with pyrite or other sulphides and iron containing minerals compared statistically by the t criteria the elements na li cu zn pb cr ni co mo fe and be are of higher content in the open pit mine tungsten is the only element of higher concentration in the underground mine the contents of ge as sr v mn y zr and p are not statistically different in both mines it was supposed that there were multiple sources of the trace elements in the deposit the source of the highly enriched elements w ge be and as most probably were the thermal waters in the source area the contemporary mineral springs are of high content of these elements another source were the hosting mesta volcanic rocks which are enriched in sb mo hf u th as li and rb some of the volcanics were hydrothermally altered and enriched or depleted of many elements thus the hydrothermal solutions were also suppliers of elements for the coals it is obvious that the contents distribution and paragenesis of the trace elements in both goze delchev coals reflect the geochemical specialization of the source area including rocks paleo and contemporary thermal waters

internal tide generation and destruction by shoaling internal tides 1 internal tide generation is usually predicted from local topography surface tides and stratification however internal tides are often observed to be unrelated to local spring neap forcing appearing intermittently in 3 5 day bursts here we suggest a source of this intermittency by illustrating how remotely generated shoaling internal tides induce first order changes in local internal tide generation theory numerical simulations and observations show that pressure perturbations associated with shoaling internal tides can correlate with surface tide velocities to generate or destroy internal tides where shoaling internal tides have random phase such as on the new jersey slope time averaged internal tide generation is unaffected but instantaneous internal tide generation varies rapidly altering internal tide energy and possibly affecting nonlinear internal waves across shelf transport and mixing where shoaling internal tides are phase locked to the local surface tide such as in double ridge systems time averaged internal tide generation is affected and may result in resonance

crustal anatexis during the influx of mantle volatiles abstract many data show that large masses of silicic magma can be formed by crustal anatexis under the influence of volatiles possibly enriched in primary water derived from a mantle source in the present paper a model of crustal anatexis accompanied by a limited influx of volatiles is suggested the water influx is not excessive no independent fluid water phase appearing in the magma convective diffusion is assumed to be the dominant mechanism of volatile transport within the silicic melt this mechanism increases the volatile flux by several orders of magnitude compared with the diffusion flux in a non convecting system a high convective flux may be generated only at specific stages of magma chamber formation in this paper a mathematical formulation of the conditions favouring this type of anatexis is given the most plausible source of deep seated water bearing volatiles beneath large silicic crust derived magma masses are mantle derived magmas which maintain vigorous convection it is shown that convective diffusion influx of volatiles from a lower layer of mafic magma into an upper layer of silicic magma leads to a quasi equilibrium situation transient two liquid eguilibrium watson 1976 in this situation the distribution coefficient of water between adjacent silicic and mafic magmas is proportional to the ratio of water solubilities in these magmas and amounts to about 1 4 by mass the silicic magma overlying the mafic magma can contain up to 6 wt water which is particularly true of the latest stages of cryatallization of the mafic magma when its water content rises and diffusion of water across the mafic silicic melt boundary becomes more efficient on the basis of our results the different stages of formation of a silicic magma are discussed the geological consequences are analyzed and some new regularities in the interpretation of geological and petrological data relevant to granitoid petrogenesis are proposed

trace and major element content and distribution in neogene lignite from the sofia basin bulgaria abstract lignite samples from the balsha seam in the sofia neogene basin were collected and ashed the coal ash was analysed for major and trace element contents the concentration of most of the elements in the coal ash was higher than the clarke value ag be cd co cr cu in mn mo ni p pb sc sn ti v and zn forty nine trace elements were determined aluminium si k ree bi zn ta tl sn sr cs u th rb au and hf have positive correlation coefficients with the ash content i e respectively high inorganic affinity but ti mn ga tb cu and cd have intermediate organic and inorganic affinity calcium mg fe s ge as be ag mo w in sb na p sc v cr ba pb ni co y and zr have high organic affinity some elements with organic affinity was also related with carbonate ca mg fe na ba p or sulphide fe s be as sb ge na mo in w ni ag tb minerals five groups of elements may be separated according to the form of occurrence in coal the first two la eu tb ce ta rb cs th sm u yb sr mn hf zn and al bi k au sn tl si associations contain elements with positive correlation with the ash content i e they show mainly inorganic affinity the elements which show negative correlation were separated in three other groups p sb ba na s mg ca as ge in w mo fe be zr y cd sc and pb ag cu cr co ni v ti associations four types of distribution of the elements along the balsha seam profile were recognised 1 elements concentrated in the low part of the seam 2 elements which have maximum concentration in the middle part of the seam 3 elements which tend to concentrate in the upper part of the coal seam 4 irregular distribution of the element contents it is established that most of the elements show high concentrations near the bottom the top or at the clay layers of the balsha seam

numerical treatment of cross shelf open boundaries in a barotropic coastal ocean model abstract using a barotropic coastal ocean model with a straight coastline and uniform cross shelf bottom slope seven different cross shelf open boundary conditions four of which are applied in either implicit or explicit form are compared in three numerical experiments 1 a mound of water is allowed to collapse and radiate waves toward the open boundaries 2 a uniform alongshelf wind stress is applied at zero time over the entire shelf and held constant for the duration of the experiment 3 a uniform cross shelf wind stress is applied at zero time over the entire shelf and held constant for the duration of the experiment the boundary condition which is most transparent to waves consists of a sponge at the outer edge of the model domain with an orlanski radiation condition at the outer edge of the sponge several open boundary conditions perform adequately in the wind stress experiments but the orlanski radiation condition alone without a sponge appears to give the best total performance of thes

notes on the marginal enrichment of germanium in coal beds germanium distribution in coal has long been a topic of interest the enrichment of ge near margins of coals including the margins of partings within the coal has been noted in many coals from numerous coalfields throughout the world in this paper a summary of literature on ge geochemistry on the upper and lower margins of coal seams with special emphasis on the literature of russia and the former soviet union and japan is presented

internal tides in the southwestern japan east sea abstract this paper investigates the internal tidal energy distribution in the southwestern japan east sea using vertical round trip travel time data from 23 pressure sensor equipped inverted echo sounders pies the records are analyzed by bandpass filtering to separate time dependent variability of the semidiurnal and diurnal bands the semidiurnal internal tides exhibit a horizontal beam pattern of high energy propagating into the open basin they originate from a restricted portion of the shelf break where the korea strait enters the ulleung basin the generation appears to occur at 200 m water depth near 35 5 35 7 n and 130 131 e where the slope of bottom topography matches that of the wave characteristics coinciding with the location where the semidiurnal barotropic cross slope tidal currents are strongest maximum vertical displacement of the thermocline interpreted as a long wave first baroclinic mode from the measured is about 25 m near the generation region annual and monthly var

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

the surface expression of semidiurnal internal tides near a strong source at hawaii part ii interactions with mesoscale currents abstract observations of semidiurnal surface currents in the kauai channel hawaii are interpreted in the light of the interaction of internal tides with energetic surface intensified mesoscale currents the impacts on internal tide propagation of a cyclone of 55 km diameter and 100 m vertical decay scale as well as of vorticity waves of 100 km wavelength and 100 200 m vertical decay scales are investigated using 3d ray tracing the doppler shifted intrinsic frequency is assumed to satisfy the classic hydrostatic internal wave dispersion relation using the local buoyancy frequency associated with the background currents through thermal wind or gradient wind balance the m2 internal tide rays with initial horizontal wavelength of 50 km and vertical wavelength of o 1000 m are propagated from possible generation locations at critical topographic slopes through idealized mesoscale currents approximating the observed currents despite the lack of scale separation between the internal waves and backgroun

depositional setting petrology and chemistry of permian coals from the parana basin 2 south santa catarina coalfield brazil abstract in brazil economically important coal deposits occur in the southern part of the parana basin where coal seams occur in the permian rio bonito formation with major coal development in the states of rio grande de sul and santa catarina the current paper presents results on sequence stratigraphic interpretation of the coal bearing strata and petrological and geochemical coal seam characterization from the south santa catarina coalfield parana basin in terms of sequence stratigraphic interpretation the precursor mires of the santa catarina coal seams formed in an estuarine barrier shoreface depositional environment with major peat accumulation in a high stand systems tract pre bonito and bonito seams a lowstand systems tract ponta alta seam seam a seam b and a transgressive systems tract irapua barro branco and treviso seams seam thicknesses range from 1 70 to 2 39 m but high proportions of impure coal coaly shale and shaley coal carbonaceous shale and partings reduce the net coal thickness significantly coal lithoypes are variable with banded coal predominant in the barro branco seam and banded dull and dull coal predominantly in bonito and irapua seams respectively results from petrographic analyses indicate a vitrinite reflectance range from 0 76 to 1 63 rrandom hvb a to lvb coal maceral group distribution varies significantly with the barro branco seam having the highest vitrinite content mean 67 5 vol whereas the irapua seam has the highest inertinite content 33 8 vol liptinite mean values range from 7 8 vol barro branco seam to 22 5 vol irapua seam results from proximate analyses indicate for the three seams high ash yields 50 2 64 2 wt considering the international classification of in seam coals all samples are in fact classified as carbonaceous rocks 50 wt ash sulfur contents range from 3 4 to 7 7 wt of which the major part occurs as pyritic sulfur results of x ray diffraction indicate the predominance of quartz and kaolinite also pyrite gypsum gibbsite jarosite and calcite were also identified in some samples feldspar was noted but is rare the major element distribution in the three seams coal basis is dominated by sio 2 31 3 wt mean value al 2 o 3 14 5 wt mean value and fe 2 o 3 6 9 wt mean value considering the concentrations of trace elements that are of potential environmental hazards the barro branco bonito and irapua seams coal base are significantly enriched in co 15 7 ppm cr 54 5 ppm li 59 3 ppm mn 150 4 ppm pb 58 0 ppm and v 99 6 ppm when compared to average trace elements contents reported for u s coals hierarchical cluster analysis identified based on similarity levels three groups of major elements and seven groups of trace elements applying discriminant analyses using trace and major element distribution it could be demonstrated that the three seams from santa catarina show distinct populations in the discriminant analyses plots and also differ from the coals of rio grande do sul analyzed in a previous study

spatial and temporal variability of the m2 internal tide generation and propagation on the oregon shelf abstracta 1 km horizontal resolution model based on the regional ocean modeling system is implemented along the oregon coast to study average characteristics and intermittency of the m2 internal tide during summer upwelling wind driven and tidally driven flows are simulated in combination using realistic bathymetry atmospheric forcing and boundary conditions the study period is april through august 2002 when mooring velocities are available for comparison modeled subtidal and tidal variability on the shelf are in good quantitative agreement with moored velocity time series observations depth integrated baroclinic tidal energy flux ef its divergence and topographic energy conversion tec from the barotropic to baroclinic tide are computed from high pass filtered harmonically analyzed model results in a series of 16 day time windows model results reveal several hot spots of intensive tec on the slope at these locations tec is well balanced by ef divergence changes in background stratific

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