the impact of hydrothermal mineral replacement reactions on the formation and alteration of carbonate hosted polymetallic sulfide deposits a case study of the artemis prospect queensland australia abstract hydrothermal sulfidation of carbonate rocks and the reverse replacement of sulfides by carbonates are important processes responsible for the formation and subsequent alteration of ore deposits these processes have been recognized in the case study of the artemis zn cu au prospect which is located in the cloncurry district within the eastern succession of the mount isa inlier nw queensland australia the high grade polymetallic mineralization displays a complex association of massive sulfides and carbonates hosted in a vertical marble lens adjacent to garnet bearing schist staurolite muscovite schist and quartzo feldspathic psammite petrographic analyses of drill core specimen by optical and electron microscopy micro x ray florescence elemental maps electron probe microanalyses cathodoluminescence and bulk geochemistry suggested three major stages of mineralization i pre ore stage marble calcite 0 ii ore stage involving sulfidation of the marble and precipitation of calcite 1 and spherical sulfide inclusions in the first episode and the formation of calcite 2 and massive sulfide in the second episode and iii post ore stage involving replacement of sulfides by calcite 3 and garnet mineral replacement reactions are dominant processes in rocks of ore stage and post ore stage the ore stage involved the dissolution of coarse and pristine calcite 0 ca0 95mn0 3fe0 2co3 and the precipitation of sulfides and calcite 1 ca0 96mn0 3fe0 1co3 and calcite 2 ca0 96mn0 3fe0 1co3 the sulfide assemblage consists of pyrrhotite sphalerite chalcopyrite galena arsenopyrite cobaltite costibite bi cubanite ag sulfides and au in decreasing order of abundance in episode 1 calcite 1 contains spherical sulfide inclusions while in episode 2 calcite 2 envelopes calcite 1 the replacement of co rich arsenopyrite fe0 75co0 26as1 13s0 83 by relatively co poor arsenopyrite fe0 86co0 15as0 99s0 99 via a coupled dissolution precipitation reaction occurred in episode 2 based on arsenopyrite geothermometry the temperatures for the first and second episode are 650 50 and 450 70 c respectively micro xrf elemental maps of the garnet bearing schist adjacent to the sulfidized marble revealed the sulfidation front where pre ore garnet and amphibole were replaced by pyrrhotite chalcopyrite au biotite and muscovite in the post ore stage calcite 2 was partially replaced by siderite and calcite 3 ca0 94mn0 4fe0 2mg0 1co3 which shows sectoral and oscillatory zoning galena was replaced by calcite 3 as documented by embayed lobate grain boundaries between these minerals and pyrrhotite fe 1 x s x 0 091 0 119 was pervasively replaced by garnet mn1 2fe1 2ca0 6 al2si3o12 the microscale investigations of the mineralization processes in the artemis orebody document the impact of hydrothermal mineral replacement reactions on metal sequestration mineral replacement reactions facilitate the formation of ore deposits and subsequent alteration processes which may lead to the loss of economic value of the deposit

changes in sulfides and platinum group minerals with the degree of alteration in the roby twilight and high grade zones of the lac des iles complex ontario canada the lac des iles complex hosts pd deposits with unusually high pd pt and pd ir ratios these high ratios have been attributed to the introduction of pd by late magmatic hydrothermal fluids the presence of hydrous silicates and low temperature sulfide mineral assemblages has been advanced as evidence for fluid overprint this idea has been investigated by documenting the change in silicate sulfide and platinum group mineralogy and texture in samples from the deposit ranging from fresh gabbronorite to extensively altered chlorite actinolite schist in addition whole rock analysis combined with laser ablation analysis of the sulfides was used to determine which phase controlled each of the pge in fresh gabbronorite the sulfide assemblage is igneous pyrrhotite pentlandite chalcopyrite and pd is present mainly in pentlandite and kotulskite pdte inclusions associated with the sulfide minerals all other pge except pt are present in solid solution in pyrrhotite and pentlandite platinum is present as sperrylite ptas2 and montcheite ptte2 inclusions associated with the sulfide minerals these observations suggest that the pge in the fresh gabbronorite were all collected by magmatic sulfide liquid in the chlorite actinolite schist the sulfide assemblage is a low temperature assemblage consisting of chalcopyrite pyrite millerite a minor amount of palladium is present in millerite but most is present as bismuth rich kotulskite and pd arsenides both of which are associated with hydrous silicate all other pge except pt are hosted by pyrite a minor amount of pt is present in pyrite but most is found as sperrylite and montcheite associated with hydrous silicate minerals the pyrite could have formed by fe loss from pyrrhotite resulting in the pyrite inheriting os ir ru and rh and fe loss from pentlandite to form millerite resulting in the millerite inheriting some pd the pge concentrations of the whole rock show there is no direct correlation between the sulfide assemblage the degree of alteration of the silicate minerals and ore grade thus although fluids have clearly altered the sulfide silicate and platinum group mineralogy and their textures it is not clear that these fluids have changed the pge content of the rocks

3d textural evidence for the formation of ultra high tenor precious metal bearing sulphide microdroplets in offset reefs an extreme example from the platinova reef skaergaard intrusion greenland abstract the platinova reef in the skaergaard intrusion east greenland is an example of a type of layered intrusion hosted precious metal enriched stratiform disseminated sulphide deposit referred to as offset reefs these typically show platinum group element pge enrichment immediately below a major increase in the abundance of cu rich sulphides with a prominent peak in au enrichment exactly at that transition between the pge rich and the cu sulphide rich zones the reasons for the relative sequence of offsets in metal peaks and the occasionally very high metal tenors have been subject to great debate here we use an integrated approach of high resolution x ray computed tomography hrxct sem synchrotron and desktop microbeam xrf mapping and thin section petrography to comprehensively classify the textural relations of the precious metal bearing sulphides of the platinova reef as an extreme end member example of an exceedingly high tenor offset deposit our results show that in the zones of pge enrichment precious metal minerals pmms are intimately associated with cu sulphide globules mostly located at or close to silicate and oxide boundaries the textures are identical in zones enriched in pd and au and thus we do not see any evidence for different processes forming the different zones the pmm cu sulphide ratio in each globule varies significantly but overall the size of the globules increases from the pd rich through the au rich and into the cu zone with a significant corresponding decrease in pm tenor as such this records a progression of exceedingly high tenor microdroplets of sulphide which progressively get larger up through the section and decrease in tenor proportionally to their size cumulus droplets of cu sulphide became enriched in metals and were trapped in situ without significant transport from their point of nucleation the transition to larger sulphides represents a change from sulphides nucleated and trapped in situ to larger ones that liquated from magma devoid of crystals and that were able to grow and sink this feature is common in all offset reef deposits and is marked by the major enrichment in au although the metal ratios of pge to au in the pd and au rich offset zones differ the identical textures and comparable mineralogy show the physical mechanisms of concentration are the same indicating a similar physical method of concentration the relative position of the pd au and cu peaks in the platinova reef is essentially the same as that in numerous other offset reefs suggesting that common overarching processes are responsible for the enrichment in metals and relative offsets in peak metal concentrations in all such deposits the most important of these processes are their relative dsul sil values and the diffusivities of the metals which determine the order of offsets and the high tenors of the smallest sulphide droplets the platinova reef therefore records the extreme enrichment via equilibrium and diffusive partitioning into sulphide liquid microdroplets very close to their point of nucleation

the detection of low magnitude seismic events using array based waveform correlation summary it has long been accepted that occurrences of a known signal are most effectively detected by cross correlating the incoming data stream with a waveform template such matched signal detectors have received very little attention in the field of detection seismology because there are relatively few instances in which the form of an anticipated seismic signal is known a priori repeating events in highly confined geographical regions have been observed to produce very similar waveforms and good signals from events at a given site can be exploited to detect subsequent co located events at lower magnitudes than would be possible using traditional power detectors even greater improvement in signal detectability can be achieved using seismic arrays running correlation coefficients from single sensors can be stacked over an array or network to result in a network correlation coefficient displaying a significant array gain if two events are co located the time separating the corresponding patterns in the wave train as indicated by the cross correlation function is identical for all seismic stations and this property means that the correlation coefficient traces are coherent even when the waveforms are not we illustrate the power of array based waveform correlation using the 1997 august 16 kara sea event the weak event that occurred 4 hr after the main event was barely detected using an sta lta detector on the spits array but is readily detected by signal matching on a single channel the main event was also recorded by the far more distant norsar array but no conventional detection can be made for the second event a clear detection is however made when the correlation coefficient traces are beamformed over all sensors of the array we estimate the reduction in detection threshold of a test signal on a regional seismic array using waveform correlation by scaling down a master signal and immersing it into seismic noise we show that for this case waveform correlation using a single channel detects signals of approximately 0 7 orders of magnitude lower than is possible using an sta lta detector on the array beam waveform matching on the full array provides an additional improvement of approximately 0 4 magnitude units we describe a case study in which small seismic events at the barentsburg coal mine on spitsbergen were detected using the signals from a major rockburst as master waveforms many spurious triggers occurred in this study whereby short sections of signal exhibited coincidental similarity with unrelated incoming wave fronts we demonstrate how such false alarms can almost always be identified and screened out automatically by performing frequency wavenumber analysis upon the set of individual correlation coefficient traces

hydrological factors in the interpretation of stable isotopic proxy data present and past a european perspective in the context of this paper stable isotopic proxies are those preserving directly or via known or calculable fractionation factors a record of 18o 16o and or 2h 1h in the water which contributed to their growth suitable proxies include amongst others tree ring cellulose bone phosphate lake sediment minerals and speleothem fluid inclusions a principal aim of studying isotopic proxies is to gain more information about past climates through a knowledge of how rainfall isotope compositions have changed over time however converting back from proxy to rainfall is not necessarily straightforward because however well the isotopic fractionation due to proxy growth or formation is understood a variety of modifying processes may have intervened between this and the actual rainfall events three main reservoirs of environmental water may contribute to the isotopic compositions of terrestrial proxy indicators surface waters soil moisture and groundwater each of these can in principle be isotopically modified compared to rainfall in the locality this review examines these effects and how they may change under different european climate types at the present day it is concluded that while groundwater isotopic compositions typically represent closely the bulk composition of rainfall under a variety of climatic regimes soil and particularly lake waters require detailed study if their isotope systematics are to be adequately understood the review also finds that to a large extent the present is the key to the past in terms of recharge processes during the late pleistocene though glaciation may have had profound isotopic consequences in certain areas while a more general aridity led to the apparent absence of recharge in most areas for much of the late devensian

sulfuric acid as an agent of carbonate weathering constrained by δ13cdic examples from southwest china abstract rock weathering by carbonic acid is thought to play an important role in the global carbon cycle because it can geologically sequestrate atmospheric co 2 current model of carbon cycle evolution usually assumes that carbonic acid is the major weathering agent and that other acids are not important here we use carbon isotopic evidence and water chemistry of springs and rivers from the beipanjiang river basin guizhou province southwest china to demonstrate that sulfuric acid is also an important agent of rock weathering the 13 c of dissolved inorganic carbon dic in the water samples ranges from 13 1 to 2 4 and correlates negatively to hco 3 ca 2 mg 2 ratios and positively to so 4 2 ca 2 mg 2 ratios these relationships are interpreted as mixing diagrams between two reactions of carbonate weathering using carbonic acid and sulfuric acid as a proton donor respectively mixing proportions show that around 42 of the divalent cations in the spring water from guizhou are originated from the interaction between carbonate minerals and sulfuric acid it is shown that 40 of this sulfuric acid is derived from the atmosphere and has an anthropogenic origin the remaining 60 are derived from the oxidative weathering of sulfide minerals in sedimentary rocks our results show the positive action of sulfuric acid on the chemical weathering of carbonate particularly we show that sulfuric acid generated by coal combustion has increased by almost 20 the weathering rates of carbonate in southwest china this is a clear evidence that human activities are changing the weathering rates of rocks and demonstrates a negative feedback on the acidification of the ocean by greenhouse gases because of the involvement of sulfuric acid in weathering reactions 63 of the alkalinity exported by rivers is derived from carbonate instead of 50 when atmospheric co 2 is the only acid involved in chemical weathering of carbonate in the guizhou province the weathering of carbonate is thus at least transiently a net source of co 2 to the atmosphere when extrapolated at global scale sulfuric acid induced carbonate weathering could counterbalance a significant part of the co 2 consumed by silicate weathering this paper highlights the competition between silicate weathering by carbonic acid and carbonate weathering by sulfuric acid for the regulation of the atmospheric co 2 level

replacement of base metal sulfides by actinolite epidote calcite and magnetite in the ug2 and merensky reef of the bushveld complex south africa interaction of base metal sulfides pyrrhotite pentlandite and chalcopyrite with aqueous fluids in the ug2 chromitite layer and the merensky reef in the western bushveld complex has produced four common replacements 1 replacement of sulfides and orthopyroxene by actinolite or tremolite 2 replacement of sulfides and plagioclase by epidote 3 replacement of sulfides by calcite and 4 replacement of sulfides by magnetite the first three replacements are directly related to the presence of sulfides in the rocks and occur at the grain scale silicate minerals that are not in direct contact with sulfides are usually not affected the replacement of sulfides by magnetite accompanies regional serpentinization superimposed on the union section platinum group minerals including ru pt and pd sulfides pt and pd tellurides and pd arsenides occur in replacement aureoles around sulfide aggregates as well as within the aggregates suggesting that the platinum group minerals are more resistant to hydrothermal alteration than the associated base metal sulfides redistribution of chalcopyrite at least at the millimeter scale variable losses of s and ni and perhaps decoupling of pt and pd at the centimeter scale took place during secondary hydrothermal alteration these effects should be considered before models of primary mineralization processes can be meaningfully applied

event discrimination using regional moment tensors with teleseismic p constraints determining whether a seismic event is an earthquake explosion collapse or something more complex can be done using regional 10 s full waveform moment tensors down to low magnitudes m 3 5 the moment tensor results can be improved for sparse station configurations when teleseismic 30 array based short period t 1 s p constraints are added the inclusion of teleseismic p aids in event discrimination because it samples the lower region of the focal sphere a region where intermediate period waveforms recorded at the surface have low sensitivity for shallow event depths the teleseismic p constraint is particularly useful in reducing the trade off between a shallow explosion and a shallow volume compensated linear vector dipole with a vertical axis in compression this trade off can complicate discrimination the teleseismic p constraint is applied to the source type analysis of the announced nuclear test of the democratic people s republic of korea on 25 may 2009 resulting in greater confidence in a dominantly explosive solution

on the mechanisms for low sulfide high platinum group element and high sulfide low platinum group element mineralization in the eastern gabbro coldwell complex canada evidence from textural associations s se values and platinum group element concentrations of base metal sulfides

the rise collapse and compaction of mt mantap from the 3 september 2017 north korean nuclear test surveillance of clandestine nuclear tests relies on a global seismic network but the potential of spaceborne monitoring has been underexploited we used satellite radar imagery to determine the complete surface displacement field of up to 3 5 meters of divergent horizontal motion with 0 5 meters of subsidence associated with north korea s largest underground nuclear test combining insight from geodetic and seismological remote sensing we found that the aftermath of the initial explosive deformation involved subsidence associated with subsurface collapse and aseismic compaction of the damaged rocks of the test site the explosive yield from the nuclear detonation with best fitting source parameters for 450 meter depth was 191 kilotonnes of tnt equivalent our results demonstrate the capability of spaceborne remote sensing to help characterize large underground nuclear tests

geological and land use control on δ34s and δ18o of river dissolved sulfate the moselle river basin france abstract the upper part of the moselle river basin northeastern france shows contrasting lithology and topography granitic formations upstream in the vosges mountains and carbonate platform downstream on the lorraine plateau we measured concentration and isotopic composition of dissolved so 4 in the moselle river and its main tributaries in order to identify the sources of sulfate rainwater lichens s fertilizers and natural gypsum were also analyzed as potential sulfate sources along the moselle river dissolved so 4 concentrations and s o isotopes display relationships which suggest two major sources of sulfates 1 a low concentration and low delta values 34 s of 6 9 and 18 o of 6 9 component upstream and 2 a high concentration and high delta values 34 s of up to 17 and 18 o of up to 13 these are likely 1 atmospheric s input with some retention time in forest soils as carbon bonded sulfur and 2 sulfates from the dissolution of evaporites from the muschelkalk and keuper formations of the lorraine plateau the madon tributary drains a basin largely used for agriculture 35 of the land surface and formed by carbonate and evaporite rocks deviation from the general 34 s 18 o trend for dissolved so 4 was found to be seasonal and related to land use and agricultural practices and are interpreted as a significant input of sulfates from fertilizers used in the area isotope mixing models indicate that between 1 1 10 7 and 1 9 10 7 mol of anthropogenic so 4 are annually exported through the madon river these values compared well with the expected annual fertilizer spreading rates in the area and demonstrate the powerful source tracing done by using s isotopes in dissolved sulfates this implies that combining isotopic fingerprinting approach to knowledge of the catchment i e land use agricultural practices river flow would provide key information for decision makers in the context of river basin management

composition of the ultramafic mafic contact interval of the great dyke of zimbabwe at ngezi mine comparisons to the bushveld complex and implications for the origin of the pge reefs the great dyke contains the world s second largest platinum resource after the bushveld complex isotopic and trace element data from the interval straddling the contact between the ultramafic and mafic sequences of the great dyke indicate a less enriched composition than in the bushveld complex great dyke sri 0 7024 0 7028 end mostly 1 to 1 ce sm 2 6 bushveld sri 705 0 709 end 5 to 7 ce sm 5 15 these data are interpreted to reflect relatively moderate amounts of contamination of the great dyke parent magma all analyzed isotopes show little variation across the main sulfide zone and the ultramafic mafic contact this corroborates earlier work by other researchers that the great dyke crystallized from a single magma type mixing of compositionally distinct magmas proposed to have caused sulfide melt saturation in the bushveld complex seemingly played little or no role in the formation of the pge mineralization in the main sulfide zone and neither did enhanced crustal contamination of specific magma batches instead sulfide melt saturation of the magma was likely triggered by silicate fractionation the mechanism of concentration of the sulfide melt remains uncertain but theoretical considerations suggest that phase sorting in response to slumping of crystal mushes possibly caused by chamber subsidence played an important role this model is consistent with the highly irregular undulating nature of the contact between the mafic and ultramafic zones of the intrusion in the hanging wall of the main sulfide zone

textural mineralogical and stable isotope studies of hydrothermal alteration in the main sulfide zone of the great dyke zimbabwe and the precious metals zone of the sonju lake intrusion minnesota usa stratigraphic offsets in the peak concentrations of platinum group elements pge and base metal sulfides in the main sulfide zone of the great dyke and the precious metals zone of the sonju lake intrusion have in part been attributed to the interaction between magmatic pge bearing base metal sulfide assemblages and hydrothermal fluids in this paper we provide mineralogical and textural evidence that indicates alteration of base metal sulfides and mobilization of metals and s during hydrothermal alteration in both mineralized intrusions stable isotopic data suggest that the fluids involved in the alteration were of magmatic origin in the great dyke but that a meteoric water component was involved in the alteration of the sonju lake intrusion the strong spatial association of platinum group minerals principally pt and pd sulfides arsenides and tellurides with base metal sulfide assemblages in the main sulfide zone of the great dyke is consistent with residual enrichment of pt and pd during hydrothermal alteration however such an interpretation is more tenuous for the precious metals zone of the sonju lake intrusion where important pt and pd arsenides and antimonides occur as inclusions within individual plagioclase crystals and within alteration assemblages that are free of base metal sulfides our observations suggest that pt and pd tellurides antimonides and arsenides may form during both magmatic crystallization and subsolidus hydrothermal alteration experimental studies of magmatic crystallization and hydrothermal transport deposition in systems involving arsenides tellurides antimonides and base metal sulfides are needed to better understand the relative importance of magmatic and hydrothermal processes in controlling the distribution of pge in mineralized layered intrusions of this type

stable isotope geochemistry of acid mine drainage from the wiśniowka area south central poland abstract this paper presents the results of a current isotopic study of pyrite mineralization acid mine drainage amd and nearby rivers and farmer s wells located in the western part of the main range holy cross mountains south central poland the principal source of dissolved sulfates in acid lakes ponds and intermittent pools is the predominant microscopic grained and locally framboidal pyrite fes2 that tends to oxidize rapidly on exposed quarry walls and unvegetated historic and current tailings piles this process is expedited by the occurrence of arsenic in the pyrite crystal structure which greatly decreases its resistance to weathering the 34s signature of pyrite from the podwi niowka quarry mean of 24 0 3 1 was different from that of the wi niowka duza quarry mean of 17 4 7 2 these values fingerprinted two basic pyrite mineralization zones assigned to lowermost and middle upper cambrian rock series respectively the 34s fes2 differences also were reflected in dissolved sulfates that displayed distinctly different 34s values 15 3 1 0 podwi niowka and 10 0 1 7 wi niowka duza these negative 34s values stand in contrast to their positive equivalents of the cambrian main range as well as in the examined rivers and farmer s wells unaffected by amd processes the acid water bodies also displayed diverse seasonal variations of 34s so42 18o so42 and 18o h2o that were linked to surface area site topography exposition to radiation changing weather patterns especially temperature and a periodical influx of rainwater or meltwater the isotope data also suggest that evaporation occurred after pyrite oxidation without a direct contact with lake pond waters which is also evidenced by the occurrence of sulfate efflorescences on podwi niowka and wi niowka quarry faces the stable s o and h isotopes have been employed for fingerprinting different geochemical processes and for assessing a potential impact of amd waters on nearby rivers and local perched aquifers particularly in case of no visual indications the s isotope signatures of ponds and pools have also been used for determining the provenance of historic and recent mine waste material

compositional and lithological controls on the pge bearing sulphide zones in the selukwe subchamber great dyke a combined equilibrium rayleigh fractionation model the platinum group element pge bearing main and lower introduction sulphide zones of the selukwe subchamber of the great dyke are an increasing number of mafic layered intrusions are made up of a series of subzones within which the ratios pd pt are reported to have distributions of platinum group elements effectively constant whereas these ratios vary significantly between pge au and base metals characterized by vertically the subzones fractionation of pd with respect to pt varies by a offset profiles offset profiles involve the vertical sepfactor of 10 and cannot be modelled using a sulphide collector aration of metal peaks and were first reported in the phase and constant partition coefficients the link with sulphide is great dyke prendergast keays 1989 wilson et al indisputable and the control is likely to have been the degree of 1989 naldrett wilson 1990 wilson tredoux oversaturation of pge micro nuggets in the magma the apparent 1990 the phenomenon has since been recognized in partition coefficients for pt and pd between silicate and sulphide the munni munni intrusion of western australia barnes liquid are dependent on the degree of oversaturation and thereby et al 1990 the skaergaard intrusion bird et al 1991 exhibit spurious correlation with the pge content of the sulphide and the rincon del tigre complex of eastern bolivia modelling replicates the pt and pd distribution and ratios only by prendergast 2000 pge are also postulated to be transdramatically changing the effective partition coefficients pyroxene ported in fluids emanating from expulsion of intercumulus compositions including tio2 are shown to be strongly dependent liquid from the crystal pile and there is strong evidence on the incompatible element content of the whole rock and specific to support such processes in several gabbroic sections linear arrays relating these variables can be related to the pge of layered intrusions such as the skaergaard intrusion subzones the overall control is rayleigh fractionation but constancy andersen et al 1998 and in the stillwater complex of the ratio pd pt and the initial pyroxene composition before re boudreau mccullum 1986 1992 in contrast the equilibration with trapped liquid within the subzones is indicative mineralized zones in the great dyke and munni munni of equilibrium crystallization this layered structure may have been intrusion are located in pyroxenite and primary magderived from liquid layers in the magma chamber matic processes have been invoked to explain the min

building an isotopic hydrogeochemical indicator of anthropogenic pressure on urban rivers this study provides evidence on the sources and pathways of trace metal contamination using isotopic tracers 34s of dissolved sulfate and 206pb 207pb of suspended particulate matter spm in an urban french river the trace metal contamination of the orge river watershed was correlated with a highly contrasted land use pattern with mainly forests and agricultural lands upstream and a highly dense urban area up to 8000 inhabitants km2 downstream in the suburbs of the parisian megacity the increase in the sulfate concentrations 0 25 1 mmol l of the dissolved compartment 0 45 m monitored during a hydrological year 2010 2011 correlated with the dissolved sulfate 34s and 18o ratios 2 to 12 and 6 to 13 respectively this result indicated that the runoff and sewage waters are important sources of water in the river particularly for the highly urbanized sites the lead enrichment factor in the spm was observed to increase according to the urbanization gradient 1 to 6 and the associated 206pb 207pb ratio indicated that the signature of the lead bearing particles transformed from a three endmember system 2001 samples to a two endmember one 2010 2011 samples over the last decade these results suggest that gasoline originated lead has disappeared from particulate fluxes since the lead additive prohibition in 2000 the lead bearing species in the orge river were also observed to originate mainly from urban activities and the reactivity of selected urban lead bearing species is discussed based on microscopic observations finally coupling the 34s and 206pb 207pb ratios provided a powerful indicator of urban influence as a function of both river hydrodynamics and physico chemical conditions

high precision location and yield of north korea s 2013 nuclear test 1 using north korea s 2009 nuclear test as reference and satellite imagery we show that the location and yield of north korea s 2013 nuclear test can be quickly and accurately determined based on seismic data north korea s 2013 nuclear test site is pinpointed by deriving relative location of north korea s 2009 and 2013 nuclear tests and using the previously determined location of the 2009 nuclear test while its yield is estimated based on the relative amplitude ratios of the lg waves recorded for both events the previously determined lg magnitude of 2009 nuclear test and burial depth inferred from satellite imagery north korea s 2013 test site is determined to be located at 41 17 26 88 n 129 4 34 68 e about 345 m south and 453 m west of its 2009 nuclear test site with a geographic precision of 94 m its yield is estimated to be 12 2 3 8 kt

analysis of sulfides in whole rock matrices by elemental analyzer continuous flow isotope ratio mass spectrometry abstract potential matrix effects in the sulfur isotopic analysis of whole rocks by elemental analyzer continuous flow isotope ratio mass spectrometry ea cfirms have been investigated by measuring mixtures of a well calibrated laboratory sulfide reference mineral and common rock forming minerals mixtures of sulfide and quartz orthoclase plagioclase kaolinite olivine magnetite ilmenite garnet halite fluorite calcite and graphite show consistent s yields and 34s values generally within 0 2 of the measured pure sulfide value however erratic results are obtained for mixtures of reference sulfide and pyroxene amphibole or biotite these minerals may suppress sample peaks cause extreme peak tailing and prohibit isotope ratio measurements pure sulfide minerals introduced after the mixtures also showed suppressed sample peaks suggesting so2 adsorption on mineral and residual ash surfaces removal of the residual ash resulted in normal measurements for reference sulfide minerals whole rocks with s concentrations in excess of 100 ppm can be successfully analyzed using ea cfirms provided that measurements are carefully monitored for evidence of so2 retention during and after combustion

concentration of platinum group elements by magmatic fluids in layered intrusions evidence leading to a model which supports the formation of pt pd reefs in a layered intrusion by the action of magmatic fluids is presented as well as some of the constraints imposed on such a model the stillwater complex is used as an example of this model within the stillwater complex no laterally continuous sulfide enriched cumulates occur above the lowermost parts of the ultramafic series until one reaches the platiniferous j m reef this sulfide poor stratigraphic interval beneath the j m reef is characterized by unusually cl rich apatite although reported sulfide modes and whole rock sulfur contents in the cumulates below the j m reef are approximately an order of magnitude lower than that expected for a sulfide saturated magma sulfide saturation prior to the formation of the j m reef is suggested by relatively high pd and pt concentrations reported in the cumulates below the j m reef as well as by the presence of sulfide as inclusions in silicate and oxide cumulus minerals hence it is suggested that the footwall cumulates to the j m reef were originally sulfide saturated but later lost sulfur to a fluid phase exsolving from inter cumulus liquid sporadic sulfide bearing pegmatoids in some of these rocks are additional evidence for late loss of sulfur these observations as well as the association of the j m reef at the first significant stratigraphic break in the cl cl f ratio of apatite and the relatively high solubility of pt and pd as aqueous cl complexes are consistent with the formation of the j m reef by exsolution of cl and volatile rich fluids from footwall intercumulus liquids which leached and transported ore components both the pge and s upward to the level of the reef using published whole rock platinum group element pge concentrations for the ultramafic and lower banded series the cumulates below the j m reef must have been enriched by a factor of at most 1 24 for pt and 1 75 for pd if these rocks were to be the source for the metals in the j m reef model raleigh fractionation calculations suggest that the cumulates beneath the j m reef could have had the required metal concentrations if during the crystallization of a parent magma containing no more than 15 ppb of either metal the average bulk solid liquid distribution coefficients for pt and pd were no more than 5 these values are consistent with assumption of sulfide saturation prior to the formation of the j m reef during solidification of intercumulus liquid the separation and loss of a cl rich fluid will deplete the residual assemblage of s and pge if 0 1 to 0 5 wt percent fluid containing 5 percent s evolved during solidification of the footwall cumulates the amount of fluid expected to be exsolved by the crystallization of approximately 2 to 10 percent fluid saturated intercumulus liquid the fluid liquid distribution coefficients for pt and pd would need to be almost as large as the sulfide liquid silicate liquid distribution coefficients to remove significant amounts of pt and pd much smaller distribution coefficients are needed if sulfide is completely lost to fluid during degassing the latter possibility is consistent with the low s contents of the footwall cumulates beneath the j m reef numerical models of the degassing of intercumulus liquids suggest that thick cumulus sequences can act as chromatographic columns to separate the pge and s during the degassing of intercumulus silicate liquids the pge being enriched at a sulfide dissolution front as upward migrating sulfide undersaturated fluids resorb cumulus sulfides zones of pge and s enrichment can occur where degassing fronts encounter stratigraphic physical chemical discontinuities such as changes in the fluid saturation temperature of the intercumulus silicate liquids

geochemistry and mineralogy of platinum group elements at hartley platinum mine zimbabwe the main sulfide zone msz is the most prominent layer of the great dyke layered intrusion carrying economic platinum group element pge mineralization at the hartley platinum mine the msz is up to some meters thick and is composed of a basal pge rich subzone which overlaps slightly with a base metal sulfide rich subzone on top based on the degree of sulfide mineralization and pge ratios the subzones can be further divided into geochemically distinct layers stratigraphically upwards the msz displays metal profiles characterized by increasing cu ni pt pd and ppge ipge ratios accompanied by a general element decoupling in the order pd pt base metals more specifically ipge pd pt ni cu co s sulfides au te bi the fine structure of the msz is regarded to reflect primary magmatic features of consecutive batches of sulfide accumulation concomitant scavenging of pge and fractionation sulfide deposition was followed by a second limited subsolidus stage of pge redistribution mineralogically most of the pd and rh is hosted in pentlandite whereas pt is dominantly present in the form of discrete platinum group minerals pgm within the msz sequence sperrylite is present throughout the pge subzone of the msz cooperite braggite occur mainly in its basal part and the pt pd bismuthotellurides concentrate at the top these findings indicate that a large proportion of the pge primarily concentrated in sulfide under magmatic conditions was redistributed in the subsolidus stage and formed discrete pgm with available reactant partners chemical gradients and magmatic hydrothermal fluids probably led to small scale redistribution of pge within the msz

horizontal and vertical variations in noble metal distribution in the great dyke of zimbabwe a model for the origin of the pge mineralization by fractional segregation of sulfide abstract a study based largely on diamond drilling undertaken specifically for research purposes has shown that in the darwendale subchamber of the great dyke of zimbabwe there are three principal sulfide zones that are located in subunits 1a and 1b of cyclic unit 1 sulfide zone 1 the main sulfide zone msz is subdivided into three subzones the base of the msz occurs at the top of the main bronzitite layer of cyclic unit 1 extending into the overlying websterite the noble metals are concentrated at the bases of each sulfide zone and subzone and decrease in concentration rapidly upwards whereas variations in the concentrations of base metals such as cu correlate well with variations in the amounts of sulfide across each zone when calculated in terms of their concentration in 100 sulfides it is found that pd decreases upwards most rapidly followed by pt and then au with the cu concentration remaining essentially constant the decrease of the noble metals is interpreted in terms of simple rayleigh fractionation as the consequence of the removal of sulfide the observed correlation between the tops and bottoms of sulfide zones with small variations in the mg number of bronzite is taken to indicate that in zones 2 and 3 sulfide segregation started as a result of crystallization increasing the s content of the resident magma in the chamber until it reached that of sulfide saturation coupled with fresh inputs of sulfide unsaturated more primitive magma causing the resident magma to become unsaturated again this recharge by primitive magma also raised the pge content of the sulfides segregating from the trapped intercumulus liquid indicating that the resident magma was becoming recharged in pge in this way subunits i and ii of sulfide zone 1 are thought to contain too much sulfide to be explicable in this way and it is suggested that mixing with a plagioclase saturated magma possibly generated around the flanks of the intrusion was responsible for these subunits the sulfides of each of the sulfide zones are more concentrated at the margin than at the axis of the great dyke but have a lower tenor of noble metals it is proposed that the axially located sulfides were the consequence of magma sulfide equilibration at a higher r factor magma sulfide ratio than those at the margin the magma sulfide partition coefficients required to explain the percentage difference in the tenors of the different noble metals between axis and margin in this way are the same as those required to explain the vertical variations in noble metal tenor in terms of the fractional segregation model

platinum group element distribution in the oxidized main sulfide zone great dyke zimbabwe in the great dyke mafic ultramafic layered intrusion of zimbabwe economic concentrations of platinum group elements pge are restricted to sulfide disseminations in pyroxenites of the main sulfide zone msz oxidized ores near the surface constitute a resource of ca 400 mt mining of this ore type has so far been hampered due to insufficient recovery rates during the oxidation weathering of the pristine ores most notably s and pd are depleted whereas cu and au are enriched the concentrations of most other elements including the other pge remain quite constant in the oxidized msz pge occur in different modes 1 as relict primary pgm mainly sperrylite cooperite and braggite 2 in solid solution in relict sulfides dominantly pd in pentlandite up to 6 500 ppm pd and 450 ppm pt 3 as secondary pgm neoformations i e pt fe alloy and zvyagintsevite 4 as pge oxides hydroxides that replace primary pgm as the result of oxidation 5 hosted in weathering products i e iron oxides hydroxides up to 3 600 ppm pt and 3 100 ppm pd manganese oxides hydroxides up to 1 6 wt pt and 1 150 ppm pd and in secondary phyllosilicates up to a few hundred ppm pt and pd in the oxidized msz most of the pt and pd are hosted by relict primary and secondary pgm subordinate amounts are found in iron and manganese oxides hydroxides the amount of pge hosted in solid solution in sulfides is negligible considerable local variations in the distribution of pge in the oxidized ores complicate a mineralogical balance experiments to evaluate the pge recovery from oxidized msz ore show that using physical concentration techniques i e electric pulse disaggregation hydroseparation and magnetic separation the pge are preferentially concentrated into smaller grain size fractions by a factor of 2 highest pge concentrations occur in the volumetrically insignificant magnetic fraction this indicates that a physical preconcentration of pge is not feasible and that chemical bulk leaching methods need to be developed in order to successfully recover pge from oxidized msz ore

reaction mechanism for the replacement of calcite by dolomite and siderite implications for geochemistry microstructure and porosity evolution during hydrothermal mineralisation carbonate reactions are common in mineral deposits due to co2 rich mineralising fluids this study presents the first in depth integrated analysis of microstructure and microchemistry of fluid mediated carbonate reaction textures at hydrothermal conditions in doing so we describe the mechanisms by which carbonate phases replace one another and the implications for the evolution of geochemistry rock microstructures and porosity the sample from the 1 95 moz junction gold deposit western australia contains calcite derived from carbonation of a metamorphic amphibole plagioclase assemblage that has further altered to siderite and dolomite the calcite is porous and contains iron rich calcite blebs interpreted to have resulted from fluid mediated replacement of compositionally heterogeneous amphiboles the siderite is polycrystalline but nucleates topotactically on the calcite as a result the boundaries between adjacent grains are low angle boundaries 10 which are geometrically similar to those formed by crystal plastic deformation and recovery growth zoning within individual siderite grains shows that the low angle boundaries are growth features and not due to deformation low angle boundaries develop due to the propagation of defects at grain faces and zone boundaries and by impingement of grains that nucleated with small misorientations relative to each other during grain growth the cores of siderite grains are aligned with the twin planes in the parent calcite crystal showing that the reactant fe entered the crystal along the twin boundaries dolomite grains many of which appear to in fill space generated by the siderite replacement also show alignment of cores along the calcite twin planes suggesting that they did not grow into space but replaced the calcite where dolomite is seen directly replacing calcite it nucleates on the fe rich calcite due to the increased compatibility of the fe bearing calcite lattice relative to the pure calcite both reactions are interpreted as fluid mediated replacement reactions which use the crystallography and elemental chemistry of the calcite experiments of fluid mediated replacement reactions show that they proceed much faster than diffusion based reactions this is important when considering the rates of reactions relative to fluid flow in mineralising systems

sulphur cycling in the drinking water catchment area of torgau mockritz germany insights from hydrochemical and stable isotope investigations the hydrochemical composition of groundwater and the isotopic composition of sulphur compounds in sediments 3 4 s of sulphide inorganic sulphate and groundwater 3 4 s 1 8 o of dissolved sulphate have been investigated to reveal the reasons for elevated concentrations of dissolved groundwater sulphate in the drinking water catchment area of torgau mockritz germany the three most important anthropogenic sources of sulphate identified in this study are historic atmospheric sulphate deposition predominantly of anthropogenic origin inorganic fertilization and dissolution of gypsum from waste dumps owing to their overlapping isotopic range no clear differentiation between the individual anthropogenic sources is possible sulphate from the oxidation of sedimentary sulphides however was recognized by its negative sulphur isotope signature 3 4 s 5 the mobilization of sulphate from different soil sulphur species is closely connected with variable isotopic fractionations resulting in a wide isotopic variation range for the sulphate entering the saturated zone generally sulphur and oxygen isotope ratios of the dissolved groundwater sulphate range from 19 to 37 vienna canon diablo troilite and from 2 to 19 vienna standard mean ocean water respectively sulphate from the majority of groundwater samples can be assigned to anthropogenic sources sulphate from sulphide oxidation is especially present in samples from the upper sampling level and the groundwater surface sulphate concentrations above 700 mg l 1 are mostly caused by the oxidation of sulphide sulphate that occurs in low and moderate concentrations dominantly originates from anthropogenic sources 3 4 s distribution patterns were used to locate the sources for the elevated sulphate concentrations in the raw water it was shown that the sulphate is not mobilized in the immediate vicinity of the production wells rather it originates in an area 1 5 km west of the intake the main mobilization mechanism there is the oxidation of reduced sedimentary sulphur species beyond its local significance this study presents a general example how changes in the sulphur cycle indicate major anthropogenically induced alterations of the hydrochemical situation in catchment areas

hydrogeochemical characteristics of streams with and without acid mine drainage impacts a paired catchment study in karst geology sw china summary a paired catchment study was used to assess hydrochemical characteristics of streams in amd acid mine drainage impacted and non amd impacted catchments in a karstic region sw china the catchments shared similar geology slope aspect area and climate but different land use since one encompassed mining activities as a result hydrogeochemical characteristics of the amd impacted water were dominantly controlled by oxidation of pyrite while that of non amd impacted were influenced by water rock reactions it is also coincident with the source of 34 s so4 in both waters upstream unit ion fluxes of the amd impacted catchment for ca mg h fe and so 4 were 17 g m 2 yr 2 g m 2 yr 0 0002 g m 2 yr 17 g m 2 yr and 136 g m 2 yr respectively while unit ion fluxes of the non amd impacted catchment were much lower than that of the amd impacted catchment along the flow fluxes of h ca mg fe and so 4 decreased in the amd impacted water but increased in the non amd impacted water the observation was coincident with variations of ion concentrations in both waters along the flow supported by phreeqc modeling of minerals such as goethite jarosite ss melanterite scorodite calcite and dolomite it suggests that the transport of constituents of interest except for ca and mg is dramatically different in these catchments results provide important information on karst system response to amd together with the baseline data to understand the degree and type of impairment

origin of brines in the upper silesian coal basin poland inferred from stable isotope and chemical data brines in the miocene formations of the upper silesian coal basin have isotopic composition close to smow which identifies them as the connate marine water however controversies exist on the origin of brines in the carboniferous formations isotopic and hydrochemical data exclude any relationship to marine water and enrichment by evaporation the most common brine which occurs at great depths can be identified as the oldest infiltration in a very hot climate 18o 2 d 20 cl content 34 to 140 g l this brine is free of so42 and u and rich in ba2 and226ra its salinity is probably related to the leaching of evaporites and intensive weathering of rocks during the rotliegendes other brines are difficult to identify because their isotopic contents are within the range of mixing between the oldest brine and the quaternary waters 18o 10 d 70 isotopic and hydrochemical data allow identification of several occurrences of brine formed by meteoric water of a warm tertiary climate after the last marine transgression in the tortonian that brine is rich in so42 and contains moderate contents of226ra and u its salinity is thought to result from leaching of miocene evaporites two other identified types of brines can be related to some infiltration periods before the last marine transgression the sources in salinity of these 2 types remain unknown mining activity results in a common occurrence of mixed brines when the quaternary component dominates its identification is easy from the isotopic composition whereas the end brine component can ususally be identified by chosen ion ratios and the presence or lack of sulphates

advanced seismic analyses of the source characteristics of the 2006 and 2009 north korean nuclear tests in 2006 and 2009 north korea conducted underground nuclear tests at a remote mountainous site in the northeastern part of the country both events were small leading to uncertainties for location yield estimation and discrimination based on seismic observations the objectives of the studies described in this paper have been to more fully exploit data from the international monitoring system ims network and other unclassified sources e g incorporated research institutions for seismology iris japanese national research institute for earth science and disaster prevention nied to analyze these nuclear tests we have used differential waveform interferometry dwif to refine relative locations for the tests and extended the methodology using observations from regional stations to estimate relative emplacement depths which are consistent with explosion source model predictions for broadband regional p wave spectral ratios topographic data from the test site were analyzed to constrain relative locations and depths needed for containment of the two tests based on normal testing practice network averaged teleseismic p wave spectra were inverted using a model based approach and provide explosion yield estimates in the range 0 6 1 0 kt for the 2006 test and 2 0 4 8 kt for the 2009 test depending on assumed emplacement depth detailed spectral analysis of broadband regional p observations are most consistent with theoretical explosion models with yields of 0 9 and 4 6 kt for the 2006 and 2009 tests respectively with associated source depths of 200 and 550 m consistent with previous studies the surface wave m s magnitudes for the 2006 and 2009 tests provide anomalously large m s yield estimates and problematic m s m b identification characteristics finite difference simulations of long period surface wave signals incorporating tensile prestress consistent with the regional tectonics lead to predicted m s values that agree much better with the observed values

environmental conditions of boreal springs explained by capture zone characteristics summary springs are unique ecosystems but in many cases they are severely threatened and there is an urgent need for better spring management and conservation to this end we studied water quality and quantity in springs in oulanka national park north east finland multivariate statistical methods were employed to relate spring water quality and quantity to hydrogeology and land use of the spring capture zone this revealed that most springs studied were affected by locally atypical dolostone limestone bedrock resulting in high calcium ph and alkalinity values using ward s hierarchical clustering the springs were grouped into four clusters based on their water chemistry one cluster consisted of springs affected by past small scale agriculture whereas other clusters were affected by the variable bedrock e g springs only 1 km from the dolostone limestone bedrock area were beyond its calcium rich impact zone according to a random forest model the best predictors of spring water chemistry were spring altitude and the stable hydrogen isotope ratio of the water 2h thus stable water isotopes could be widely applicable for boreal spring management they may also provide a rough estimate of groundwater flow route i e whether it is mainly local or regional which largely determines the chemical characteristics of spring water our approach could be applied in other boreal regions and at larger spatial scales for improved classification of springs and for better targeted spring management

assessing the impact of serwis mine tailings site on farmers wells using element and isotope signatures holy cross mountains south central poland this paper presents the results of a geochemical and isotopic study of technogenic soils and acid pool waters in the abandoned mine tailings pile and its potential impact on the adjacent farmers wells at the village of serwis south central poland the acid tailings pools showed strong trace element and ree signals these acid pools were featured by the predominance of medium rare earth elements mree with a strong positive gd anomaly the technogenic soils also revealed a mree roof shaped pattern but with distinct positive excursions in gd sm eu and ce the 34s so42 signatures of acid pool waters mean of 1 3 were close to those of soils and pyrite means of 2 3 and 3 2 respectively the waters of four farmers wells exhibited nearly the same 34s so42 values 0 7 4 0 as the nearby acid pool waters 0 3 3 1 the similar 34s isotope signatures combined with the highest contents of dissolved so42 181 577 mg l in these wells suggest that the tailings pile is a potential source of so42 derived from pyrite weathering this relationship may also be evidenced by a spatial site variable dendrogram that groups these four wells into one cluster at the linkage distance dlink dmax 100 53

the origin of pyrite mineralization implications for late cambrian geology of the holy cross mountains south central poland abstract this paper presents results of a petrographic mineralogical and geochemical study of ore gangue and rock forming minerals that occur within the upper cambrian furongian age siliciclastic rocks of the wi niowka massif western part of the main range holy cross mountains south central poland this area is characterized by the presence of ubiquitous pyrite that makes up two stratiform mineralization zones assigned to the early and middle late cambrian giving rise to acid mine drainage the oldest zone comprises additionally sedimentary breccias with intraclast supported pyrite cement the predominant microscopic colloform and partly framboidal pyrite typically shows high concentrations of as up to 8 23 wt and a distinct enrichment in the light sulfur isotope 34s from 41 4 to 23 6 the occurrences of large amounts of as rich pyrite showing strongly negative 34s values are rather uncommon in paleozoic sedimentary formations worldwide that exhibit distinctly smaller amounts of as and mostly enrichments in heavier sulfur isotope 34s up to 63 another specific feature of the wi niowka rock series is the presence of ree bearing aluminophosphate and phosphate minerals that occur primarily in clayey silty shales and bentonites based on the results obtained a sequence of hydrothermal index minerals was discriminated including pyrite whose grains are usually made of alternating arsenic rich and arsenic poor bands as well as paragenetic assemblages of dickite nacrite xenotime and the crandallite series of aluminum phosphate sulfate minerals both mineral composition and specific microtextures are indicative of multistage hydrothermal activity that took place in the wi niowka depositional basin during the late cambrian time this is in distinct contrast to the remaining part of the main range which is devoid of the hydrothermal pyrite imprint moreover the results of this study give insight into the complex sedimentary and early diagenetic history of the southwestern passive margin of the baltica craton this currently makes up a part of the ysogory block terrane that borders on the trans european suture zone separating the precambrian east european craton from the paleozoic platform of central europe this study is important because we still lack the full knowledge about the hydrothermal processes that took place in early paleozoic depositional basins

relative locations of the october 2006 and may 2009 dprk announced nuclear tests using international monitoring system seismometer arrays abstract waveform data recorded at seven of the international monitoring system ims seismometer arrays are used to measure the relative times of teleseismic p signals with three methods analyst picks and two methods that make full use of the capabilities of seismometer arrays the cross correlation of array beams and the average of channel by channel cross correlations these times are used to estimate the relative locations of the 9 october 2006 and 25 may 2009 democratic people s republic of korea announced underground nuclear tests the 2009 test is found to have occurred about 1 8 0 8 km to the west and 0 4 0 6 km to the north of the 2006 test the use of cross correlation reduces the standard deviation of the travel time residuals from 0 05 to 0 01 sec enabling the two epicenters to be statistically distinguished with high confidence this result demonstrates the power of a small number of ims seismometer arrays at teleseismic distances to detect and relatively locate small explosions with high precision

distribution and controls of platinum group element and base metal mineralization in the darwendale subchamber of the great dyke zimbabwe three major sulfide zones containing platinum group elements pge have been identified in the upper part of the ultramafic sequence of the great dyke the pge are at the bases of the sulfide zones the lower two have sparse sulfide mineralization over a thick interval the upper zone contains higher grade in a thinner stratigraphic layer none of the current models for the formation of stratabound sulfide deposits in layered intrusions adequately accounts for the mineralization the two lower sulfide zones are interpreted as resulting from progressive fractional segregation of sulfide from the silicate magma whereas the upper zone may have resulted from mixing of a relatively primitive magma at the base of the chamber with an evolved liquid derived from near the roof

does more mean less in epicentre estimation abstract the epicentres of explosions at two test sites balapan shagan river former soviet union and lop nor china are estimated using the onset times of p from only three or four array stations at teleseismic distances the epicentres of the explosions are known to within about 1 km from studies that make use of information from satellite imagery these estimates are taken to be the true epicentres with the true epicentres differences between the true travel times and the times from travel time tables are estimated the differences include a component path effects that results in epicentre bias comparing our estimates using three or four stations with the true epicentres shows that with correction for path effects most of the epicentres are within 5 km of true and even without correction most estimated epicentres are within 10 km of true the results confirm the conclusion of evernden that if reading error in p times has a standard deviation of a few tenths of a second reliable epicentres can be obtained given readings from only a few stations this implies what has been noted by others that for epicentre estimation better results can be obtained with a few well read p times from a constant network of the most reliable and sensitive stations than by using uncritically all the available times even without correction for path effects none of the explosions with times free from possible clock errors falls outside a circular 1000 km 2 region 1000 km 2 being the search area allowed for an on site inspection under the comprehensive test ban treaty the results suggest that rather than try and calibrate the whole of the international monitoring system being set up to verify the test ban it would be better initially to concentrate on calibrating the few stations with the longest recording history and lowest detection thresholds

calculation of oxygen isotope fractionation in hydroxyl bearing silicates abstract the modified increment method has been applied to the calculation of oxygen isotope fractionation factors for hydroxyl bearing silicate minerals the order of 18o enrichment obtained in common rock forming minerals is pyrophyllite kaolinite tourmaline talc prehnite topaz illite phengite lepidolite muscovite staurolite epidote glaucophane serpentine chlorite tremolite hornblende phlogopite biotite humite norbergite ilvaite hydroxyl bearing silicates are enriched in 18o relative to hydroxyl groups but depleted in 18o relative to anhydrous counterparts three sets of self consistent fractionation factors between quartz and the hydroxyl bearing silicate minerals between calcite and the silicate minerals and between the silicate minerals and water have been calculated for a temperature range of 0 1200 c the fractionation factors calculated for mineral pairs are applicable to isotopic geothermometry in igneous metamorphic and sedimentary petrology they can be used as a test of isotopic equilibrium or disequilibrium in natural mineral assemblages over all temperature ranges of geological interest the difference in oxygen isotope composition between the hydroxyl bearing mineral and the oh group is quantitatively demonstrated to be temperature dependent and therefore can be used as a single mineral geothermometer

stable sulfur and oxygen isotope ratios of the świetokrzyski national park spring waters generated by natural and anthropogenic factors south central poland abstract this paper presents the results of an isotopic study of spring waters in wietokrzyski holy cross mountain national park np south central poland the 34 s v cdt and 18 o v smow of soluble sulfates n 40 varied from 0 5 to 18 1 and from 3 5 to 12 2 respectively the average 34 s values are closely similar to those of rainwater soils and rocks comprising scattered pyrite this suggests that soluble sulfates in the springs originated from mixing of recent and historic deposition sulfates derived from pyrite oxidation and cs mineralization in soils and debris an additional anthropogenic sulfur input inorganic fertilizer occurs in the water of spring s 61 located in the wietokrzyski national park buffer zone the 18 o v smow of spring waters n 4 were in the range of 10 6 to 10 2 indicating that they are derived from vadose groundwater in np this was the first isotope study of spring waters in the national parks of poland it enabled the determination of sulfur pathways and discrimination between natural and anthropogenic sources of this element in a relatively pristine area

lop nor revisited underground nuclear explosion locations 1976 1996 from double difference analysis of regional and teleseismic data we have used seismic signals recorded at regional and teleseismic distances to determine precise locations of 19 underground nuclear explosions 13 in vertical shafts and 6 in horizontal tunnels carried out between october 1976 and july 1996 at the lop nor test site in the southern xinjiang province of china in addition to first and later arriving phase pick data from the international seismological centre and chinese bulletins we use waveform cross correlation methods to measure relative arrival times between the explosions with an accuracy of about 10 msec we adapted the double difference algorithm to work with regional and global network data and applied it to the combined lop nor data set to remove the effects of uncertainty in the earth model specifically we determined locations of more recent tests to the accuracy of the cross correlation data while simultaneously determining the relative locations of the older tests for which digital waveforms are not available to the accuracy of the phase pick data in general our locations are consistent at the 90 confidence level with previously published locations when compared in a common reference frame with anthropogenic features from satellite imagery and with high resolution elevation data for four explosions however our results indicate that a particular explosion may have been carried out in a different shaft than previously noted or previously associated features must be ruled out because of their location outside a particular error ellipse mislocations of explosions from associated satellite features are less than 1 km for all 13 shaft events the pattern of tunnel explosion locations falls within a region of suitable overburden required for containment eighteen lop nor locations have solution qualities at the gt2 level or better and are well suited to calibrate ims stations for the purpose of monitoring compliance with the comprehensive nuclear test ban treaty manuscript received 4 september 2003

anthropogenic sulfate loads in the rio grande new mexico usa abstract the sources of so 4 along a 550 km stretch of the rio grande in new mexico and western texas were investigated using stable s isotopes during 2007 and 2008 the 34 s of dissolved so 4 in the rio grande surface water varied over a narrow range from 1 6 to 0 9 which was consistent with the 34 s of local fertilizers 2 1 to 1 6 and was not consistent with paleozoic evaporite sources of so 4 in regional bedrock 7 6 to 12 9 this is likely due the fact that so 4 is the major component of n p k fertilizers used in the rio grande valley constituting about half of the total fertilizers by mass the so 4 cl ratios of the groundwater system are relatively low 0 06 to 3 compared to the fertilizer source suggesting that more cl is added to the rio grande from geological sources as compared to so 4 in the mesilla basin in southern new mexico we identified zones of mixing between recharging irrigation water with groundwater within the depth range of 50 200 m below the ground surface for this aquifer principal component analysis pca indicated that na k cl concentrations were largely attributable to geological sources and so 4 mg ca concentrations to anthropogenic sources here an additional anthropogenic source of so 4 with a 34 s of 2 7 was linked to anaerobic decomposition of manure on a horse farm in this case so 4 concentrations 800 mg l increased by about three times compared to background so 4 concentrations in groundwater 2 so 4 in fertilizer manufacturing anthropogenic so 4 fluxes to rivers and shallow aquifers from irrigation waters can be significant worldwide

drought induced pulses of so42 from a canadian shield wetland use of δ34s and δ18o in so42 to determine sources of sulfur abstract following summer drought periods pulses of elevated so 4 2 concentrations are frequently observed in streams draining forested catchments that contain wetlands delays in the recovery of freshwater streams and lakes in eastern canada from historically high levels of acidic precipitation have been partially ascribed to these periodic pulses of so 4 2 climate in eastern canada has also changed within the last 25 a with a documented increase in summer dryness and duration of droughts in small forested catchments in the turkey lakes watershed tlw so 4 2 concentrations in streams draining wetlands can be elevated by up to a factor of 7 during post drought discharge events compared to the annual average two neighbouring catchments one with a series of cascading wetlands and one without any wetlands were selected for comparison stable s and o isotope ratios were analyzed in samples of bulk precipitation streams and groundwaters to examine sources of so 4 2 in post drought pulses 34 s so 4 2 in the streams and groundwaters show that so 4 2 is retained in the wetland via so 4 2 reduction and stored in the upper peat profile nitrate is elevated in soil and groundwaters at tlw due to high rates of nitrification in forest soils and the presence of no 3 can be used to identify piezometers unaffected by so 4 2 reduction 18 o so 4 2 shows that higher concentrations of so 4 2 in deeper groundwater are likely due to oxidation of organic s and not a geologic source of reduced s following drought the low 34 s so 4 2 in streams is consistent with wetland retention by so 4 2 reduction and much lower than so 4 2 released by weathering in deep glacial till and bedrock high so 4 2 groundwaters and geologic sources do not contribute to the so 4 2 pulses in streams isotopic patterns over 6 a were similar pulses of so 4 2 in the wetland catchments following drought are a result of the oxidation of s previously reduced and stored in the wetland

the bushveld complex south africa formation of platinum palladium chrome and vanadium rich layers via hydrodynamic sorting of a mobilized cumulate slurry in a large relatively slowly cooling subsiding magma chamber platinum group element pge deposits in the bushveld complex and other layered intrusions form when large incompletely solidified magma chambers undergo central subsidence in response to crustal loading resulting in slumping of semi consolidated cumulate slurries to the centres of the intrusions and hydrodynamic unmixing of the slurries to form dense layers enriched in sulfides oxides olivine and pyroxene and less dense layers enriched in plagioclase the most economic pge cr and v reefs form in large multiple replenished intrusions because these cool relatively slowly and their central portions subside prior to termination of magmatism and complete cumulate solidification the depth of emplacement has to be relatively shallow as otherwise ductile crust would not be able to flex and collapse in smaller intrusions cooling rates are faster subsidence is less pronounced and where it occurs the cumulate may be largely solidified resulting in insignificant mush mobility and mineral sorting layering is thus less pronounced and less regular and continuous and the grades of the reefs are lower but the reefs can be relatively thicker an additional factor controlling the pge cr and v prospectivity of intrusions is their location within cratons intra cratonic environments offer more stable emplacement conditions that are more amenable to the formation of large layered igneous bodies furthermore intrusions sited within cratons are more readily preserved because cratons are underlain by thick buoyant keels of harzburgite that prevent plate tectonic recycling and destruction of crust

accurate locations of nuclear explosions at the lop nor test site using alignment of seismograms and ikonos satellite imagery locations are estimated of 11 underground nuclear explosions conducted between 26 may 1990 and 29 july 1996 at the lop nor test site in western china to perform the analysis seismic recordings were obtained from the center for monitoring research cmr u s national data center and incorporated research institutions for seismology iris data management center using recordings with adequate signal to noise ratios p wave arrivals are picked manually by aligning waveforms of the events at common stations this provides very precise relative phase timings i e with relative errors typically much less than 0 1 sec based on analysis of commercial ikonos satellite imagery the locations of three explosions are fixed and used as master events the other events are located relative to the nearest master event after correcting their travel times by the travel time residuals relative to iasp91 of the master events location estimates of the 25 september 1992 and 29 july 1996 nuclear tests are within about 100 m of each other the 90 confidence error ellipse for the 29 july 1996 event has a semimajor axis of less than 0 3 km the results indicate that these two tests were likely conducted in the same tunnel location estimates of nine explosions conducted at the eastern zone of the lop nor test site are within 140 to 490 meters of vertical boreholes and infrastructure to support nuclear testing observed in ikonos imagery the location estimates of the eleven chinese explosions are all considered to be well within one km of the true detonation points and hence are categorized as gt1 events as defined by yang et al 2000a these solutions allow seismic travel times to be calibrated accurately for the lop nor region at seismographic stations of the international monitoring system ims manuscript received 23 october 2001

stable isotopic constraints on fluid rock interaction and cu pge s redistribution in the sonju lake intrusion minnesota the sonju lake intrusion part of the 1 1 ga midcontinent rift related beaver bay complex is a 1 200 m thick strongly differentiated layered sequence of mafic cumulates located in northeastern minnesota basal melatroctolite and dunite layers are overlain by troctolite gabbro fe ti oxide rich gabbro apatite diorite and monzodiorite stratigraphic intervals rich in pt pd cu and s occur over 500 m in the fe ti oxide rich gabbro and apatite diorite units peak concentrations show offsets that are similar to those found in other tholeiitic layered intrusions concentrations of pd in excess of 100 ppb are confined to the lowermost 25 m of the interval copper shows a sharp increase to 630 ppm above the pd rich interval sulfur contents are low 375 ppm in the cu rich interval but they increase to values as high as 3 150 ppm above in the apatite diorite disseminated sulfides in the intrusion have 34s values that range from 2 2 to 3 per mil vienna canyon diablo troilite v cdt and suggest that contamination by country rock sulfur was not an important process in the formation of the metal rich interval 18o values of plagioclase from the intrusion range from 5 6 to 12 0 per mil v smow and indicate that a relatively low 18o fluid 18o 3 5 interacted with the rocks of the intrusion at temperatures less than 275 c clinopyroxene and fe ti oxides ilmenite with minor amounts of titanomagnetite show much more restricted ranges in 18o values 4 6 5 7 and 5 5 6 7 per mil respectively and attest to the kinetic control of the oxygen isotope exchange process the externally derived fluid that interacted with rocks now enriched in platinum group elements pge cu and fe sulfide minerals locally liberated sulfur and replaced chalcopyrite and pyrite with goethite in the cu rich zone goethite that replaces chalcopyrite may contain up to 8 5 weight percent cu it is evident that hydrothermal alteration resulted in a decoupling of copper and sulfur with sulfur being transferred out of the cu rich interval interaction between rocks in the pge cu s interval of the sonju lake intrusion and an externally derived fluid at low temperatures modified what appears to have been a primary stratigraphic metal sulfur zonation the effects of hydrothermal alteration on pge and base metal sulfide mobility and redistribution must be understood before models of primary zonation processes can be meaningfully applied

sulfur cycling in an acid mining lake and its vicinity in lusatia germany the sulfur cycle plays a key role in the hydrochemical development of lignite and coal mining districts which are often characterized by acid mine drainage identification of sulfur sources and transformations is essential if we are to understand the current status of acid lakes and propose successful remediation strategies we utilized stable isotope 34ssulfate 18osulfate 34sdissolved sulfide 18owater and hydrochemical data of lake and groundwater samples as well as the concentrations and isotope ratios of various sedimentary sulfur compounds acid soluble sulfate ass acid volatile sulfur avs chromium reducible sulfur crs in aquifer and lake sediments for assessing the biogeochemical sulfur cycle in a lusatian acidic mining lake ml111 and the surrounding area pyrite oxidation is the dominant source of sulfate and iron in the two aquifers west and east of mining lake ml111 concentration and isotope data for dissolved sulfate suggest that bacterial dissimilatory sulfate reduction became an increasingly important process in the flow direction of the western aquifer thereby improving water quality in contrast bacterial sulfate reduction was only of local importance in the dump aquifer on the eastern side of the lake oxygen isotope ratios of the lake water sulfate and mass and isotope balances demonstrate that 80 of the sulfate in mining lake ml111 is derived via groundwater influx from the dump aquifer with the remainder contributed by the western aquifer in lake pyrite oxidation or bacterial sulfate reduction in the water column are insignificant the latter process is restricted to the monimolimnion which represents less than 1 of the lake volume hence the potential for natural generation of alkalinity by bacterial dissimilatory sulfate reduction is presently low for successful remediation of ml111 it is essential to reduce significantly the continuous input of sulfate and acidity from inflowing dump groundwater

geochemistry and stable sulfur and oxygen isotope ratios of the podwiśniowka pit pond water generated by acid mine drainage holy cross mountains south central poland abstract the paper presents the results of a geochemical and isotopic study of acidic pond water in the abandoned podwi niowka quarry poland the scope of investigations also encompassed mineralogical and isotopic studies of pyrite and related supergene minerals compared to similar sites throughout the world the pit pond water examined is characterized by a very low ph averaging 2 64 0 33 and simultaneously very low concentrations of so 4 2 geometric mean of 237 57 mg l 1 fe ii 4 8 3 4 mg l 1 fe iii 10 0 6 2 mg l 1 and other trace elements this acidity has been generated by complex processes of as rich pyrite oxidation combined primarily with hydrolysis precipitation and transformation of fe oxyhydroxysulfates and oxyhydroxides into goethite the specific mineralogy of ore and gangue minerals but especially the lack of acid buffering constituents has additionally contributed to the very low ph and element concentrations of the toxic elements the high content of as 1111 1879 mg kg 1 in the western part of pit pond sediment may be of great concern especially when using lime as a neutralizing agent of the acidic water the 34s of soluble so4 varied from 19 8 to 11 1 and was different from that of efflorescent sulfates 25 7 to 25 4 and host pyrite 25 4 2 5 the comparison of the 18o so 4 2 2 0 1 2 and 18o h2o 6 2 3 5 values indicated that the pyrite underwent bacterially catalyzed oxidation by two natural oxidants primarily by fe3 and to a lesser extent o2

isotope geochemistry of drainage from an acid mine impaired watershed oakland california abstract oxidation of sulfides at the leona heights sulfur mine has resulted in the liberation of acid so4 and metals to leona creek previous research at the site has indicated fe ii oxidation at rates faster than would be predicted by abiotic oxidation alone particularly in the segment of stream between the adit and leona street sample stations in order to assess the mechanisms responsible for sulfide oxidation samples were collected for isotopic analysis of water and so4 the results of which were used to develop a stoichiometric isotope balance model this exercise indicated that the percentage of water derived oxygen in so4 increased spatially from between 56 and 64 at the adit to between 71 and 72 at leona street illustrating that increased sulfide oxidation via fe iii was occurring within or as water flows over the waste rock relative to water emanating directly from the former mine the incorporation of water derived oxygen in so4 during pyrite oxidation is a process controlled by fe oxidizing bacteria such as a ferrooxidans at low ph the role of bacteria was further supported by estimates of the rate constant for fe oxidation between sampling stations yielding values that were approximately 106 faster than abiotic fe oxidation alone stable isotopic analysis of water further indicates a close correlation of adit spring water to the local meteoric water line while 3h data indicate a groundwater apparent age or time of travel from its primary zone of recharge of