ice moraine and landslide dams in mountainous terrain we review recent work on ice moraine and landslide dams in mountainous terrain thus complementing several comprehensive summaries on glacier dams in intracontinental and arctic areas of low relief we discuss the roles of tectonic and climatic forcing on ice moraine and landslide dam formation and sudden drainage and focus on similarities and differences between their geomorphic impacts on confined valleys drained by steep bedrock and gravel bed rivers despite numerous reported failures of natural dams in mountain belts throughout the world their relevance to long term dynamics of mountain rivers remains poorly quantified all types of dams exert local base level controls thus trapping incoming sediment and inhibiting fluvial bedrock incision pervasive geomorphic and sedimentary evidence of outburst events is preserved even in areas of high erosion rates suggesting that sudden dam failures are characterized by processes of catastrophic valley floor aggradation active channel widening and downstream dispersion of sediment during which little bedrock erosion seems to be achieved we find that in the absence of direct evidence of former dams a number of similarities among the geomorphic and sedimentologic characteristics of catastrophic outburst flows may give rise to ambiguous inferences on the dam forming process this is especially the case for tectonically active mountain belts where there is ample and comparable potential for the formation and failure of ice moraine landslide and polygenetic dams concomitant with climatic oscillations or earthquake disturbance hence the palaeoclimatic implications of erroneously inferring the cause of dam formation may be significant we recommend that future research on natural dams in mountainous terrain addresses a climate and earthquake controlled systematics in the pattern of formation and failure b quantification of response of mountain rivers to catastrophic outburst events and their concomitant process sequences c elaboration of a comprehensive classification of natural dams in mountainous terrain with special attention to polygenetic dams d physical based modelling of dam formation failure and routing of water and sediment outbursts and e quantitative controls on the contribution of natural dams to sediment budgets in mountainous terrain

a jokulhlaup near sondre stromfjord west greenland and some effects on the ice sheet margin description de la vidange d un lac marginal par un tunnel sous glaciaire les 19 et 20 aout 1984

geochemistry and isotope systematics of sulphur in the mixing zone of bahamian blue holes abstraet a profile of aqueous s species concentrations and stable isotope compositions is presented for the mixing zone of cousteau s blue hole north andros bahamas together with similar but less detailed results from two other blue holes these data show that s o and s 2 are produced by bacterially mediated sulphate reduction near the base of the mixing zone and that these species are reoxidized at shallower levels acidity generated by oxidation can contribute to corrosion of limestone walbrock estimated rates of such corrosion range up to 1200 mm wall rock recession per 10 ka at cousteau s blue hole equivalent to 16 porosity generation per l0 ka and are comparable with rates of dissolution caused by inorganic mixing corrosion

a history of jokulhlaups from strandline lake alaska u s a les vidanges brutales du strandline lake se produisent tous les 1 a 5 ans la vidange est precedee par le developpement d un golfe de velage dans le lobe du triumvirate glacier qui barre le lac et par le remplissage de petits lacs sur le glacier on analyse le mecanisme a partir de cartes photogrammetriques dressees avant et apres la vidange

triggering and drainage mechanisms of the 2004 glacier dammed lake outburst in gornergletscher switzerland 1 to investigate the triggering and the drainage mechanisms of a glacier dammed lake outburst we conducted high frequency measurements of the ice surface motion in the vicinity of gornersee an ice marginal lake on gornergletscher switzerland during the outburst event in july 2004 the ice surface within a distance of 400 m from the lakeshore moved vertically upward by up to 0 1 m this vertical surface motion cannot be explained by vertical straining of ice which was measured in one of the boreholes therefore we suggest the separation of the glacier sole from the bed was caused by subglacially drained lake water our observation indicates that the lake water drained as a sheet like flow through the space created by the basal separation the upward surface motion was greater in the region where the ice flotation level was exceeded by the lake level implying that the ice barrier was breached when the lake water hydraulically connected to the bed and lifted up the glacier in addition to the centimeter scale vertical ice motion three survey stakes located within 100 m from the lake showed extraordinarily large vertical displacement of 0 5 3 0 m associated with abrupt changes in horizontal flow direction a plausible interpretation is that the marginal ice wedge bent upward because of the buoyancy force generated by the drained water such bending is possible if subglacial and englacial fractures formed at about 200 m from the glacier margin and acted as a hinge the newly formed and preexisting englacial fractures probably took the role of inducing englacial water drainage which preceded the outburst

geochemistry of coal mine drainage groundwater and brines from the ibbenburen mine germany a coupled elemental isotopic approach abstract a coupled elemental isotopic approach is applied to reconstruct the origin and chemical evolution of mine drainage groundwater and brines from the carboniferous anthracite coal mine in ibbenburen germany all solutions are characterized by an increase in salinity with depth as well as by an increase in 34s 32s isotopic ratios of dissolved so42 br cl and na cl ratios in deep na cl type water indicate halite dissolution as the common source of salinity 34sso4 values increase up to 21 1 vcdt linking the salinity to the migration of groundwater from the surrounding mesozoic sediments 87sr 86sr ratios between 0 7108 and 0 7135 and elevated alkali concentrations indicate ongoing water rock interaction of the evaporite derived brines with the carboniferous siliciclastic rocks of the mine a positive correlation of 87sr 86sr ratios with 2hh2o and 18oh2o values suggests mixing of the brines with isotopically heavy formation water within the carboniferous bedrock the oxidation of pyrite is the dominant sulfate source in shallow mine drainage and groundwater with a relatively low ionic strength i

jokulhlaup initiation by ice dam flotation the significance of glacier debris content ice dam flotation is a commonly described mechanism for the initiation of jokulhlaups catastrophic floods from ice dammed lakes but predictions of the critical lake depth required for flotation often differ from the actual lake depth at which flotation occurs glacier debris content is identified as an insufficiently recognized variable in ice dam flotation it is demonstrated that high debris contents could suppress flotation and thereby affect the timing mechanism and magnitude of catastrophic lake drainage events the density of the part of the glacier forming the ice dam rather than pure ice density is the key to predicting ice dam flotation

a m gurnell and m j clark eds 1987 glacio fluvial sediment transfer an alpine perspective chichester etc john wiley and sons ltd

models for the archean thermal regime a variety of different regionalized thermal evolution models are presented all models include an oceanic style of heat loss in which mantle convection penetrates to the surface in the form of spreading and subducting plates in continental regions the lithosphere is assumed to act as a conductive lid on mantle convection that can be either layered or mantle wide the continental lithosphere is defined in different ways it can be of fixed thickness insensitive to temperature or extend to some fixed cutoff temperature a thermally controlled rheological lithosphere when a fixed temperature is used widespread melting occurs in the archean and one has the further option of allowing these melts to erupt onto the surface thus providing a new heat transfer mechanism and also a general subsidence of the continental lithosphere due to the continuous volcanic loading the models are first used to determine the concentration of heat producing elements required to have a present day mantle potential temperature of 1350 c starting from a high temperature 2000 c 4 5 billion years ago the results depend primarily on whether the mantle is layered if layered 15 30 ppb uranium normalized to the silicate portion of the earth and withk u 104 th u 3 8 are needed while mantle wide cases need uranium concentrations in excess of 35 ppb the models are also used to calculate the thermal structure of continental lithosphere through time only lithospheres of fixed thickness 175 km can explain the recent discovery of diamonds with model ages of 3 2 3 4 billion years for a thick lithosphere to have existed in the archean it would seem most likely that its thickness be the result of some chemical distinction rather than simply its rheological properties such chemically distinct lithosphere would have greater likelihood of surviving to the present which raises the issue of biased preservation

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

majorite partition behavior and petrogenesis of the earth s upper mantle the partitioning of la sm yb sc and major elements between majorite garnet and ultrabasic liquid has been studied experimentally at 16 gpa and 2000 c liquidus majorite possesses a si mg ratio of 1 05 as compared to the cl chondritic ratio of 0 95 so that extraction of more than 50 of majorite from a chondritic mantle composition would be required to obtain the pyrolite si mg ratio of 0 78 in the upper mantle liquidus majorite is enriched in al sc and yb compared to the melt by almost a factor of two and is similarly depleted in ca sm and ti thus extensive majorite fractionation would necessarily imprint non chondritic sm yb sm sc al ca and al ti ratios on the coexisting liquid these partition relationships demonstrate that the present upper mantle which possesses these elements approximately in chondritic relative abundances cannot have experienced prior separation of more than about 10 of a majorite garnet phase

isotope geochemistry of waters affected by mining activities in sierra minera and portman bay se spain the objective of this work was to evaluate processes affecting waters from portman bay by way of stable isotopic analysis particularly h and o stable isotopes from water and s and o from dissolved sulfates in addition surface waters from sierra minera were examined for the purpose of determining if these waters are affected by similar processes the results obtained indicate that portman bay waters are meteoric and marine infiltration only takes place in the deepest layers near the shore or if water remains stagnated in sediments with low permeability the main source of sulfate was the oxidation of sulfides resulting in the liberation of acid sulfate and metals in order to assess the mechanism responsible for sulfide oxidation the stoichiometric isotope balance model and the general isotope balance model were tested suggesting that the oxidation via fe3 was predominant in the surface and controlled by acidithiobacillus ferrooxidans while at depth sulfate reduction occurred

origin of komatiite at high pressures abstract experimental melting relations to 20 gpa demonstrate that the commonly accepted model of komatiite formation by non invariant melting olivine liquid is too restrictive komatiites could also have formed by pseudoinvariant melting olivine pyroxene garnet liquid modified spinel majorite liquid along the anhydrous solidus at high pressures the mgo content of komatiites cannot be used to infer the degree of partial melting in the mantle there would have been little change in mgo at a high pressure pseudoinvariant point even for degrees of partial melting that ranged from very small to over 80 instead the mgo content of komatiites may be a better indication of the depth of partial melting than it is the degree of partial melting late archean komatiites containing 20 28 mgo could have been generated at depths ranging from about 130 to 260 km early archean komatiites from the barberton mountain land could have formed at depths corresponding to the present day transition zone or at shallower levels from an unusually primitive mantle source komatiites which originated by partial melting in a lower mantle formed by majorite fractionation should have geochemical characteristics that have not yet been reported this indicates that either melting did not extend into the lower mantle or if it did the upper and lower mantles were isolated by a chemical and thermal boundary layer in archean times

controls on bacterial sulphate reduction in a dual porosity aquifer system the lincolnshire limestone aquifer england abstract chemical and sulphur isotopic analyses are presented of fissure waters and pore waters in the deep confined zone of a dual porosity carbonate aquifer some of the fissure waters show good evidence for bacterial sulphate reduction with low concentrations of sulphide present which is strongly to moderately depleted in 34 s relative to sulphate the sulphur geochemistry is best interpreted as mixing between i a reduced water with sulphide 60 depleted in 34 s relative to sulphate and ii a sulphate rich water from up dip in the aquifer in addition sulphide oxidation occurs where sufficiently oxidizing water is drawn in by abstractions the large isotope fractionation factor associated with the sulphidic waters is probably the result of redox cycling of sulphur with little net reduction rather than a true kinetic fractionation factor by contrast pore waters in the sulphate reducing zone show little or no evidence for the effects of sulphate reduction despite the fact that the pore waters represent a significant reservoir of sulphate for reduction some pore waters have been modified recognizably by diffusional exchange with the fissure waters but the aquifer matrix has not been colonized by sulphate reducing bacteria probably because porethroats in the limestone are too small for bacteria to pass physical exclusion of bacteria from the aquifer matrix and limited diffusional exchange are likely to exert fundamental controls on bacterial redox processes in dual porosity aquifer systems and other systems with low permeability due to small pore interconnections

application of isotopic and geochemical studies to explain the origin and formation of mineral waters of staraya russa spa nw russia there are two main types of mineral waters used in the staraya russa spa 1 the saline waters of the middle and upper devonian arukjula shventoy aquifer with isotopic composition of o from 10 7 to 11 3 and h from 81 3 to 85 and 2 the brackish waters of the upper devonian sargayev daugava aquifer with isotopic composition of o from 12 5 to 12 9 and h from 93 0 to 94 1 hydrogeological conditions within the spa and its vicinity are complex due to hydraulic contacts between artesian aquifers and the saline waters ascension into shallower fresh water aquifers the studies revealed that saline waters of the arukjula shventoy aquifer are mixtures of approximately equal fractions 0 5 of snow melt water of o around 21 7 and seawater like end member of isotopic composition similar to modern ocean water i e vsmow the brackish waters of the sargayev daugava aquifer are result of mixing between infiltration waters and saline waters ascending from deeper arukjula shventoy aquifer the fraction of saline water may reach from around 0 2 to 0 4 the sulfur s and oxygen o isotopic composition of sulfates dissolved in mineral waters indicate that their source is connected with marine sulfates the ionic ratios of major chemical compounds corroborate the presence of the connate seawater like component in the hydrogeological system which is responsible for the observed chemical composition of mineral waters extracted in staraya russa spa

melting equilibria in multicomponent systems and liquidus solidus convergence in mantle peridotite the melting of undepleted mantle peridotite proceeds through a temperature interval which decreases with increasing pressure if liquidus and solidus actually meet in the range 100 150 kb as suggested by herzberg 1983 peridotite must transform there directly to a melt of its own composition thermodynamic analysis shows that such a liquidus solidus meeting would be very unlikely in a system as chemically complex as mantle peridotite and would require that unanticipated phase equilibrium relations suppress all incongruent melting behavior but takahashi and scarfe s 1985 preliminary experiments suggest that the upper mantle itself may indeed have a special composition with respect to phase equilibrium relations between liquids and solids at very high pressure if so mantle peridotite composition cannot be generated as a crystal accumulate or melting residue because these two popular theories of origin are difficult to reconcile with a supposed eutecticlike composition if upper mantle peridotite were itself a solidified liquid composition produced either as a partial melt or more likely as a crystallization residue of some more primitive melt composition representative of the whole mantle an approach of liquidus to solidus might be expected at high pressure although the phase relations of herzberg 1983 and herzberg and o hara 1985 remain implausible

carbon chemistry and groundwater dynamics at natural analogue site ruprechtov czech republic insights from environmental isotopes abstract hydrological geochemical and environmental isotope data from groundwater wells at ruprechtov natural analogue site were evaluated to characterize the flow pattern and c chemistry in the system the results show that water flow in the tertiary sediments is restricted to 1 2 m thick zones in the so called clay lignite horizon with two different infiltration areas in the outcropping granites in the western and south western part of the investigated area generally the flow system is separated from the underlying granite by a kaolin layer up to several tens of metres thick differences in stable isotope signatures in the northern part of the site indicate very local connections of both flow systems via fault zones the observed increase of 13c values and decrease of 14c activities in dissolved inorganic c during evolution of the groundwater from the infiltration area to the clay lignite horizon was modelled using simple open and closed system models as well as an inverse geochemical model netpath which included changes in other geochemical parameters the results from both types of models provided some insights into timescales of groundwater flow but mainly revealed that additional sources of c are active in the system these are very likely biodegradation of dissolved and sedimentary organic c doc and soc as well as the influx of endogenous co2 the occurrence of microbial degradation of soc in the clay lignite layers is indicated by the increase of biogenic dic doc and phosphate concentrations the impact of microbial so4 reduction on this process is confirmed by an increase of 34s values in dissolved so 4 2 from the infiltration area to the clay lignite horizon with an enrichment factor of 11 the very low doc concentrations of 1 5 mg c l in the clay lignite horizon with an organic matter content up to 50 c is probably caused by very low availability of organic matter to the processes of degradation and doc release demonstrated by extraction experiments with soc

sulfur isotope studies to quantify sulfate components in water of flooded lignite open pits lake goitsche germany abstract a system of connected lignite mining pits part of the former goitsche mining complex germany was flooded with river water between 1999 and 2002 a considerable accumulation of acid associated with oxidized sulfides in sediments was seen as a critical point for the development of the lake water to characterize the components contributing to the supply of dissolved lake water so4 hydro chemical and isotope investigations with respect to groundwater pore water in the sulfide bearing sediments river water and lake water were performed 34s of pore water so4 that was dominated by oxidized pyrites ranges around 25 vcdt and differs strongly from river water so4 with about 4 4 thus interactions between lake water and sediments were particularly pronounced during the first phase of flooding for this period a more quantitative estimation of the so4 components in the lake water was difficult because of the heterogeneous so4 distributions between the different sub basins of the lake and according to the flooding process itself later a component separation was attempted following mixing of the whole lake which first occurred in spring 2002 a very heterogeneous groundwater environment with respect to highly variable so4 concentrations and 34s values and changing interaction with the forming lakes proved to be one of the most important limitations in the calculations of the mixing

sulphur and oxygen isotopes of dissolved sulphur species in formation waters from the dogger geothermal aquifer paris basin france isotopic analyses of the s in sulphides and sulphates from formation waters were made at 35 geothermal wells exploiting the dogger geothermal aquifer of the paris basin isotopic analyses of the o of the dissolved sulphates were also made on 12 of these the results show a distribution of the 34s of the sulphates according to geographic zones that also correspond to variations in the geochemistry of the fluids in particular the sulphide content samples taken in the seine st denis area and in the areas north and west of paris show high 34s values ranging from 26 3 to 48 9 values of 34s for sulphides range from 8 5 to 5 and are interpreted as reflecting the effect of bacterial reduction in a confined part of the basin modelling this reduction by a rayleigh distillation mechanism made it possible to calculate a value of 1 038 0 003 for the coefficient of fractionation between the sulphates and sulphides we show that an important part of the sulphides formed by bacterial reduction has been subtracted from the fluid by deposition south of paris and in the val de marne the 34s values for the sulphates are more uniform ranging between 22 4 and 26 6 despite the existence of bacterial activity this is most probably due to a higher rate of flow of the waters entailing renewal of the sulphate stock the isotopic composition of the o of the sulphates for the seine st denis area and the areas west and north of paris is very uniform between 16 1 and 17 1 despite the wide range in 34s 26 3 to 48 9 for the same samples the calculated isotopic temperatures are close to those measured in situ these results suggest either that sulphate water isotopic equilibrium was established after the reduction or that the coefficient of o fractionation is very low 1 003 during bacterial reduction

geochemistry of highly acidic mine water following disposal into a natural lake with carbonate bedrock abstract acid mine drainage amd from the zn pb ag bi cu deposit of cerro de pasco central peru and waste water from a cu extraction plant has been discharged since 1981 into lake yanamate a natural lake with carbonate bedrock the lake has developed a highly acidic ph of 1 mean lake water chemistry was characterized by 16 775 mg l acidity as caco3 4330 mg l fe and 29 250 mg l so4 mean trace element concentrations were 86 8 mg l cu 493 mg l zn 2 9 mg l pb and 48 mg l as which did not differ greatly from the discharged amd most elements showed increasing concentrations from the surface to the lake bottom at a maximal depth of 41 m e g from 3581 to 5433 mg l fe and 25 609 to 35 959 mg l so4 the variations in the h and o isotope compositions and the element concentrations within the upper 10 m of the water column suggest mixing with recently discharged amd shallow groundwater and precipitation waters below 15 m a stagnant zone had developed gypsum saturation index si 0 25 and anglesite si 0 1 were in equilibrium with lake water jarosite was oversaturated si 1 7 in the upper part of the water column resulting in downward settling and re dissolution in the lower part of the water column si 0 7 accordingly jarosite was only found in sediments from less than 7 m water depth at the lake bottom a layer of gel like material 90 wt water of ph 1 with a total organic c content of up to 4 40 wet wt originated from the kerosene discharge of the cu extraction plant and had contaminant element concentrations similar to the lake water below the organic layer followed a layer of gypsum with ph 1 5 which overlaid the dissolving carbonate sediments of ph 5 3 7 in these two layers the contaminant elements were enriched compared to lake water in the sequence as

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

stable sulfur and oxygen isotopes as geochemical tracers of sulfate in karst waters abstract karst water resources which are extremely sensitive to mining activities are critical for the support of human societies and ecological systems in many regions worldwide in order to determine the sources and fate of dissolved sulfate in low ph karst waters hydrochemical variations of karst waters with and without acid mine drainage amd impacts were investigated along with stable isotope dynamics as expected hydrochemical characteristics and isotopic compositions of the amd and amd downstream water adw were dramatically different from that of the non amd impacted water naw the sources of sulfur isotopes in sulfate were predominantly pyrite oxidation for the amd and adw and atmospheric deposition for the naw based on the general isotope balance model the relative proportions of sulfate oxygen derived from water and air were calculated the mean proportion of sulfate oxygen derived from water in adw was roughly double that of amd this suggests that the sulfate associated with amd is predominantly influenced by aerobic pyrite oxidation while that of adw is likely affected by the dissolution of pyrite under anaerobic conditions in reservoir sediment this observation was coincident with the noted variations of hydrochemical characteristics and was supported by principal component analysis these results provide a better understanding of how stable isotopes of sulfate and water can be used to track mining contamination in karst aquifers which could benefit remediation planning for these distinctive systems

melting experiment on a model chondritic mantle composition at 25 gpa we have conducted melting experiments on a chondritic mantle composition in the five component system cao feo mgo al2o3 sio2 at 25 gpa the liquidus phase at this pressure is majorite garnet and the second crystallizing phase is mg silicate perovskite or magnesiowustite these phases seem to be consumed into the melt at almost the same temperature the present experiments indicate that majorite garnet fractionation might have occurred in the chondritic primitive mantle if the partial molten zone extended to a depth equivalent to the upper part of the lower mantle in the early stages of terrestrial evolution

chemical and isotopic variations in the wiśniowka mala mine pit water holy cross mountains south central poland in 2005 and 2006 hydrogeochemical study was carried out in the bipartite wi niowka mala pit lake of the holy cross mountains south central poland this is the largest acidic water body in poland this report presents the element concentrations in the water and sediment stable sulfur and oxygen isotope ratios in the soluble sulfates and stable oxygen isotope ratio in the water the scope of the investigation also encompassed mineralogical examinations scanning electron microscope x ray diffraction of the sediment the results of this study show that there is a spatial and temporal variability in concentrations of most elements and sulfur isotope ratios in the examined pit lake the water of the western pond displayed a lower ph with a mean of 3 73 and higher conductivity 390 s cm 1 as well as higher concentrations of sulfates 156 mg l 1 and most of the cations and anions the concentrations of fe2 and fe3 averaged 0 8 and 0 4 mg l 1 in contrast the eastern pond water revealed a higher ph mean of 4 36 lower conductivity 293 s cm 1 and lower sulfate 90 mg l 1 and trace metal levels similar variations were recorded in the stable sulfur isotope ratios the 34sv cdt so42 values in the water of the western pit pond were in the range of 6 7 to 4 6 mean of 5 6 whereas that in the eastern pit pond ranged from 2 2 to 0 9 1 6 the alkalinity of the entire lake water was below 0 1 mg l 1 caco3 no distinct difference in the 18ov smow so42 was noted between the western and eastern pit ponds compared to the purple pond in the sudetes poland and similar sites throughout the world the examined pit lake is highlighted by distinctly low concentrations of sulfates iron and other trace metals based on this and other studies performed in the holy cross mountains a conclusion can be drawn that the so42 in the wi niowka mala pit lake water is a mixture of so42 derived from the following sources 1 pyrite oxidation especially in the western pond water 2 leaching of soluble sulfates from soils and waste material as well as 3 subordinate deposition of airborne sulfate precipitation

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

long term mineralogical and geochemical evolution of sulfide mine tailings under a shallow water cover abstract the long term influence of a shallow water cover limiting sulfide mineral oxidation was examined in tailings deposited near the end of operation in 1951 of the former sherritt gordon zn cu mine sherridon manitoba canada surface water pore water and core samples were collected in 2001 and 2009 from above and within tailings deposited into a natural lake mineralogical and geochemical characterization focused on two contrasting areas of this deposit i sub aerial tailings with the water table positioned at a depth of approximately 50 cm and ii sub aqueous tailings stored under a 100 cm water cover mineralogical analyses of the sub aerial tailings showed a zone of extensive sulfide mineral alteration extending 40 cm below the tailings surface moderate alteration was observed at depths ranging from 40 to 60 cm and was limited to depths 60 cm in contrast sulfide mineral alteration within the submerged tailings was confined to a

recent climatic change and catastrophic geomorphic processes in mountain environments climatic warming during the last 100 150 years has resulted in a significant glacier ice loss from mountainous areas of the world certain natural processes which pose hazards to people and development in these areas have accelerated as a result of this recent deglaciation these include glacier avalanches landslides and slope instability caused by glacier debuttressing and outburst floods from moraine and glacier dammed lakes in addition changes in sediment and water supply induced by climatic warming and glacier retreat have altered channel and floodplain patterns of rivers draining high mountain ranges the perturbation of natural processes operating in mountain environments caused by recent climatic warming ranges from tens of decades for moraine dam failures to hundreds of years or more for landslides the recognition that climatic change as modest as that of the last century can perturb natural alpine processes has important implications for hazard assessment and future development in mountains even so these effects are probably at least an order of magnitude smaller than those associated with late pleistocene deglaciation ca 15 000 to 10 000 years ago

hydrologic and geomorphic effects of temporary ice dammed lake formation during jokulhlaups glacial outburst oods jokulhlaups occur frequently in glaciated environments and the resultant ooding causes geomorphic change and in some instances damage to local infrastructure during some jokulhlaups oodwater is stored temporarily in ice marginal locations in july 1999 a linearly rising jokulhlaup burst from solheimajokull iceland during this remarkable event subglacial oodwater pooled transiently in two relict ice dammed lake basins before draining suddenly back into solheimajokull the signi cance of such rapid formation and attendant drainage of temporary ice dammed lakes during jokulhlaups has not been addressed consequently this paper i assesses the hydrologic and geomorphic effects of temporary ice dammed lake formation caused by lake basin retro lling and ii discusses the impact and signi cance of transient retro lling under jokulhlaup conditions pre and post ood eldwork at solheimajokull enabled the impact and signi cance of lake basin retro lling to be assessed field evidence demonstrates that the july 1999 jokulhlaup had an unusually rapid rise to peak discharge resulting in subglacial oodwater being purged to ice marginal locations the propensity for temporary retro lling was controlled by rapid expulsion of oodwater from solheimajokull coincident with locations suitable for oodwater storage floodwater inundated both ice marginal lake basins permitting signi cant volumes of sediment deposition coarse grained deltas prograding from the ice margin and boulders perched on scoured bedrock provide geomorphic records of sudden retro lling the depositional characteristics of lake basin deposits at solheimajokull are similar to jokulhlaup sediments documented in proglacial settings elsewhere however their depositional setting and association with ice marginal landforms is distinctive findings suggest that temporary ice dammed lake formation and drainage has the capacity to alter the shape of the ood hydrograph especially if drainage of a temporary lake is superimposed on the original jokulhlaup deposits associated with lake basin retro lling have a long term preservation potential that could help to identify temporary ice dammed lake formation in modern and ancient glacial environments copyright 2003 john wiley sons ltd

isotopic evidence for processes of sulfur retention release in 13 forested catchments spanning a strong pollution gradient czech republic central europe sulfur isotope systematics were studied in 13 small catchments in the czech republic similar in topography v shaped valley and vegetation norway spruce the sites differed in elevation rainfall bedrock soil type and s pollution across the sites 34 5 values decreased in the order bulk deposition runoff spruce throughfall c horizon soil a b horizon soil 0 horizon soil bedrock means of 5 5 4 8 4 7 4 6 4 2 3 1 and 1 5 o respectively some of the sites had a net export of s while others accumulated s sites exporting s were located in the polluted north where atmospheric s input started to decrease in 1987 sites retaining s were located in the relatively unpolluted south sulfur isotope composition of runoff depended on whether the catchment accumulated or released s sites releasing s had runoff 34 s values lower than deposition in contrast sites retaining s had runoff 34 s values higher than deposition across the sites the 34 5 values of runoff were not correlated with 34 s values of bedrock indicating that the contribution of bedrock to s in runoff was negligible the 34 s values of runoff were strongly positively correlated with the 34 s values of soil sulfur present in the c horizon of soils was mainly derived from atmospheric deposition not bedrock sulfur isotope mass balances were constructed for each catchment making it possible to quantify the difference between 34 s values of the within catchment source sink of s and runoff s sulfur isotope mass balances indicated that the sink for the retained s at unpolluted sites and the source of the released s at polluted sites were isotopically fractionated by the same amount relative to runoff s inorganic and organic processes were considered as possible causes for this observation biological s cycling involves a variety of reactions some of which fractionate s isotopes in contrast adsorption desorption of inorganic sulfate in soil and weathering of s containing minerals do not fractionate s isotopes therefore the within catchment source sink of s must be largely a result of biological s cycling organic s cycling played an important role over a wide range of atmospheric s inputs from 13 to 130 kg s ha 1 yr 1

frequency and characteristics of glacier floods in the swiss alps damage due to glacier floods in the swiss alps occurs about once every two years at present despite the pronounced retreat of glaciers during the twentieth century and the installation of many water reservoirs which act as flood retention basins over half 60 to 70 of the observed floods are caused by outbursts of marginal glacier lakes or sudden breaks of ice dams and 30 to 40 by ruptures of water pockets in a glacierized mountain region as densely populated as the swiss alps even debris flows triggered by outbursts of very small water masses may be dangerous historical information about glacier floods in the swiss alps although incomplete and heterogeneous is used as an empirical basis for an attempt to recognize potential hazards at an early stage by considering outburst processes volumes of water involved potential peak discharge values lithology and inclination within the reach of glacier streams

geochemical processes in a highly acidic pit lake of the iberian pyrite belt sw spain abstract compared with pit lakes originated by coal mining little is known about in lake neutralization processes in pit lakes from sulfide ore mining in hard rock substrates which are typically very deep and acidic and receive low carbon c inputs and groundwater flows physicochemical processes in water and sediments from a pit lake san telmo 130 m deep in the iberian pyrite belt were investigated san telmo is a meromictic and highly acidic ph 2 8 pit lake due to ph buffering by precipitation of fe iii minerals schwertmannite and jarosite the sediments have a low abundance of c below 0 60 and iron minerals below 0 12 compared to most coal mining pit lakes in san telmo sediments iron reduction and sulfide oxidation may be thermodynamically favored due to low ph values in pore waters below 3 8 and the presence of reactive iron although schwertmannite is the main ferric mineral precipitating in the water column mineralogical analyses reveal a low abundance of schwertmannite in the sediment this may be due to the preferential use of this mineral in reduction reactions mediated by bacteria together with a low replenishment rate of the schwertmannite pool in the sediment the transformation of reactive iron schwertmannite and jarosite into goethite may limit sulfate reduction promoting acidic conditions in the sediment as long as the acid mine drainage continues to discharge into the lake the ph buffering exerted by ferric minerals in the sediments will limit the neutralization of the ph by sulfate reduction

geomorphic implications of glacier outburst flooding noeick river valley british columbia an outburst flood from ape lake in october 1984 severely affected channel and floodplain morphology of noeick river this event estimated to have exceeded 103 m3 s 1 was as much as 2 4 times greater than the probable maximum meteorological flood storage of water in ponds lakes and floodplain margins resulted in attenuation of the flood peak as it progressed downstream as a result flood effects were most evident in the alluvial reaches of upper noeick river below ape lake between km 10 and km 23 here the channel zone widened from a preflood average of 75 m to almost 200 m the area of eroded valley bottom increased by about 2 5 times and a cumulative length of 2 5 km of valley side colluvial fans was eroded transported sediment stored in the floodplain and along valley margins resulted in aggradation of up to 0 75 m except in restricted reaches where limited sediment supply and increased stream power caused degradation of up to 3 m a second and fractionally larger outburst flood in august 1

melting of garnet peridotite to 13 gpa and the early history of the upper mantle by analogy with the evolution of the moon it has been suggested that the earth may have had a magma ocean or liquid outer layer before 3 800 myr ago 1 its presence would have had profound implications for the primary stratification of the mantle into upper mantle transition zone and lower mantle2 3 an essential constraint on this hypothesis is a knowledge of the high pressure melting characteristics of mantle material generally assumed to be peridotite in the upper mantle we recently described4 the first melting experiments on mantle peridotite to 14 gpa using spinel iherzolite klb 1 from kilbourne hole new mexico we showed that partial melts close to the solidus at 5 7 gpa are komatiitic in composition and that the solidus and liquidus converge at high pressures here we report further melting experiments on garnet iherzolite phn1611 from thaba putsoa lesotho we confirm the convergence of the solidus and liquidus and we show a negative dt dp slope for the liquidus above 7 gpa these observations are briefly discussed in terms of their importance to the petrological evolution of the upper mantle and the presence of a magma ocean in the early archaean

use of isotope fractionation of sulfate sulfur and sulfate oxygen to assess bacterial desulfurication in a sandy aquifer abstract the unconfined aquifer of the fuhrberger feld consists of 20 30m sands and gravelly sands with unevenly distributed reduced sulfur compounds and small lignitic pebbles in vertical direction two hydrochemically different zones with specific solute transformations are present an upper portion with bacterial denitrification with reduced sulfur compounds as electron donors and a deeper portion with hydrochemical indications of reduction of the aqueous sulfate in the study area ten multilevel groundwater sampling wells were installed sampling and interpretation was based on a two dimensional vertical plane groundwater flownet and on the knowledge of the landuse upgradient of the multilevel wells the concentration and isotopic composition of the sulfate at the entrance into the zone of sulfate reduction is controlled by sulfate of groundwater recharge as well as sulfate formed during denitrification the recharge sulfate shows clear landuse specific differences in concentration and isotopic composition under arable land an average concentration of 60 mg so 4 l 1 with values of 34 s close to 3 cdt diablo meteorite standard canon and of 18 o about 8 standard mean ocean water smow was measured whereas under coniferous forest an average of 100 mg so 4 l 1 with 34 s 2 and 18 o 4 5 was found in the denitrification zone no significant sulfur isotope fractionation occurs during oxidation of reduced sulfur the oxygenisotopic composition of the newly formed sulfate denitrification sulfate depends on the 18 o content of nitrate acting as oxygen donor and on the 18 o content of groundwater in which the oxidation occurs under certain assumptions a 18 o 0 54 was calculated for the oxygen of the newly formed sulfate consequently with increasing sulfate concentrations i e with the admixture of denitrification sulfate a decrease of the 18 o values from about 8 to 2 was observed in the zone of sulfate reduction both the 34 s and 18 o values of the residual sulfate increase with decreasing sulfate concentrations thus proving the existence of bacterial reduction of the aqueous sulfate this sulfate reduction follows a rayleigh process with calculated enrichment factors of 34 9 7 for 34 s and 18 6 for 18 o respectively a plot of 34 s vs 18 o gives a good linear correlation with a slope close to 1 1 4 data on concentration and isotopic composition of sulfate and on the hydraulically derived groundwater age are used for kinetic considerations the results of a multilevel well for depths between 10 and 17m are given as an example the bacterial reduction can be considered as first order reaction with a half life between 75 and 100 years

sources and impact of sulphate on groundwaters of triassic carbonate aquifers upper silesia poland summary groundwater within the unconfined or semi confined parts of triassic carbonate aquifers in upper silesia poland contains high concentrations of sulphate up to 290 mg l sometimes in excess of drinking water limits 250 mg l to assess the influence of different possible sulphate sources isotopic analyses of s and o were performed on groundwater sulphate and potential sulphate sources and combined with literature data three dominant sources of sulphate were delineated based on the geological and literature study and supported by the mixing relations between inverse concentration of sulphate and its isotopic compositions these sources are i sulphate from rainfall ii weathering of sulphide minerals in ore deposits in the aquifer forming carbonate rocks iii dissolution of sulphate evaporites in the triassic sequence fortunately these three sources have distinctive s and o isotope compositions and thus their contributions to the total dissolved sulphate could be estimated the application of linear mixing models for three sources in the dual isotope system allowed the impact of the three different sulphate sources on particular parts of the aquifers to be calculated the average isotopic composition of sulphate in abstracted groundwater indicates that the most important source of sulphate is sulphide weathering contributing about 50 of total sulphate the second most significant source of sulphate input is rainfall and it is characterised by a mean contribution of 30 application of monte carlo analysis that incorporates the full variability in distributions of isotopic compositions for the three sources and all mixing fractions between them gave the most probable ranges of the dissolved in groundwater sulphate this analysis indicated that the proportion of sulphate derived by sulphide oxidation is comparable with the estimations based on linear models this study has shown that the water quality of these important groundwater resources is under threat from both natural sources i e metal sulphide oxidation and gypsum dissolution analysis of the mathematical models analysis shows that the first process is the predominant source of sulphate in groundwater however the highest concentrations of dissolved sulphate are positively correlated with the increasing proportion of sulphate derived from gypsum dissolution moreover one should keep in mind that natural processes might be anthropogenically accelerated due to variable water demands and groundwater abstraction eventually the statistically second order source of sulphate rainfall might contain surface derived contaminants and its contribution to the total load of sulphate might indirectly indicate the vulnerability of aquifers for the pollution

evaluation of petroleum hydrocarbon biodegradation in shallow groundwater by hydrogeochemical indicators and c s isotopes biodegradation is one of the main natural attenuation processes in groundwater contaminated with petroleum hydrocarbons in this work preliminary studies have been carried out by analyzing the concentrations of total petroleum hydrocarbons tph dissolved inorganic carbon dic dominant terminal electron accepters or donors as well as 13cdic and 34sso4 to reveal the biodegradation mechanism of petroleum hydrocarbons in a contaminated site the results show that along groundwater flow in the central line of the plume the concentrations of electron acceptors ph and e h increased but tph and dic decreased the 13cdic values of the contaminated groundwater were in the range of 14 02 to 22 28 pdb and 7 71 to 8 36 pdb which reflected a significant depletion and enrichment of 13c respectively the increase of dic is believed to result from the non methanogenic and methanogenic biodegradation of petroleum hydrocarbon in groundwater meanwhile from the contaminated source to the downgradient of the plume the 34s in the contaminated groundwater became more depleted the rayleigh model calculation confirmed the occurrence of bacterial sulfate reduction as a biodegradation pathway of the petroleum hydrocarbon in the contaminated aquifers it was concluded that stable isotope measurements combined with other biogeochemical measurements can be a useful tool to prove the occurrence of the biodegradation process and to identify the dominant terminal electron accepting process in contaminated aquifers

a comparison of two recent jokulhlaups from an ice dammed lake sondre stromfjord west greenland the hydro graphs of two jokulhl aups resulting from the sudden drainage of an ice d ammed lake in west greenland in 1984 and 1987 are compared the first flood had a similar peak discharge to the second but drained only two thi rds of the total volume of the 1987 event which amounted to 32 36 x 106 m3 in 36 h calcula tions based on the lake refill time suggest that it drains every 2 3 years but that peak flows may be variable from flood to flood the timing of the joku lhlaups in relation to the melt season may reflect variations of water pressure within the subglacial drainage networks and changes in the

using stable and radioactive isotopes for the investigation of contaminant metal mobilization in a metal mining district abstract naturally occurring stable and radioactive isotopes were used as environmental tracers to investigate contaminant metal mobilization processes in a metal smelter dump mainly consisting of slag water emerging from the dump at a spring is heavily contaminated by metals the smelter dump contains minor amounts of flue dust a material which shows a high potential for metal mobilization nearby dumps mainly consist of low grade ore concentration patterns of 238 u 226 ra and 210 pb determined in sediment deposited close to the contaminated spring reveal the flue dust to be the major local metal source rather than the slag or the low grade ore contamination pathways inside the dump were investigated using hydrological chemical and isotopic data strong negative correlation between water discharge and metal concentration in the spring water suggests besides short term dilution of the metal concentration by direct rainwater runoff distinct long term dilution of the spring water by groundwater being discharged at a significantly increased rate as a result of heavy rains 18 o and d signatures of rain local groundwater and spring water confirm the importance of groundwater derived from the local aquifer another hydrological component with importance for metal mobilization was found to be water that is recharged in the dump itself tritium analysis allowed an assessment of the probable residence time of that water component in the smelter dump since that water component seems to represent a major local contamination pathway the findings of the study are of substantial importance for site remediation planning as a primary result it could be stated that covering the dump would not result in any noteworthy short term improvement of the spring water quality first significant effects would only be visible after 2 3 decades at the earliest

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

the kolka karmadon rock ice slide of 20 september 2002 an extraordinary event of historical dimensions in north ossetia russian caucasus on 20 september 2002 an enormous rock ice slide and subsequent mud flow occurred on the northern slope of the kazbek massif northern ossetia russian caucasus it started on the north northeast wall of dzhimarai khokh 4780 ma s l and seriously affected the valley of genaldon karmadon immediate governmental actions available scientific information first reconstructions hazard assessments and monitoring activities as well as initial expert judgments recommendations are documented in order to enable more detailed analyses and modelling of the event by the wider scientific community among the most remarkable aspects related to this event are 1 the relation between the recent event and somewhat smaller but quite similar events that occurred earlier in historical times 1835 1902 2 the interactions between unstable local geological structures and complex geothermal and hydraulic conditions in the starting zone with permafrost cold to polythermal hanging glaciers and volcanic effects hot springs in close contact with each other 3 the erosion and incorporation of a debris covered valley glacier largely enhancing the sliding volume of rocks ice firn snow water and probably air to a total of about 100 106m3 and 4 the astonishingly high flow velocities up to 300 km h 1 and enormous length of travel path 18 km plus 15 km of debris mud flow this extraordinary case illustrates that large catastrophic events in high mountain regions typically involve a multitude of factors and require integrated consideration of complex chains of processes a task which must be undertaken by qualified groups of experts

mining lakes as groundwater dominated hydrological systems assessment of the water balance of mining lake plessa 117 lusatia germany using stable isotopes in the present study the stable isotopes 18o and 2h were used for assessment of the water balance in a heterogeneously structured catchment area in the lusatian lignite mining district in particular for estimation of the annual groundwater inflow and outflow igw and ogw of mining lake plessa 117 the application of stable isotopes was possible since the water exchange in the catchment area had reached steady state conditions after the abandonment of mining activities in 1968 and the filling of the voids and aquifers by re rising groundwater in the years thereafter diverging slopes of the evaporation line and the global meteoric water line manifested as evaporation from the lake catchment area the calculated isotope water balance was compared with the commonly used surface water balance which is unable to differentiate between igw and ogw and with a local groundwater model the groundwater model calculated an igw of about 811 000 m3 yr 1 and an ogw close to zero whereas the isotope water balance showed fluxes of about 914 000 and 140 000 m3 yr 1 respectively considering the contribution of the groundwater inflow to the total annual input into the lake it and the mean residence time where the groundwater model and the isotope water balance calculated 42 and 47 for it and 4 3 and 3 9 years for respectively it was shown that both water balance calculation methods led to comparable results despite the differences in igw and ogw copyright 2008 john wiley sons ltd

late glacial lakes in the thompson basin british columbia paleogeography and evolution during the decay of the cordilleran ice sheet 10 000 13 000 bp glacial lakes developed within valleys that dissect the interior plateau of british columbia in this paper we 1 illustrate a procedure for assessing paleo water planes that has general application 2 document lake paleogeography and evolution in the thompson valley 3 provide new data on the glacio isostatic response of the central cordillera and 4 present new evidence of its late glacial environment we employ geomorphology and sedimentology digital elevation models and new technologies differential global positioning systems ground penetrating radar and geographic information systems to refine paleogeographic reconstructions of glacial lakes glacial lake thompson and glacial lake deadman were ribbon shaped width to length ratio 3 100 deep 140 to 50 m lakes that contained significant water volumes 84 24 km3 they lengthened to the west and their water level lowered as ice decayed final ice dam failure resulte

flow dynamics of groundwater and soil water in the former heap gessenhalde at the uranium mining area of ronneburg a stable isotope approach stable isotopes 2hwater 18owater as well as 18osulphate and 34ssulphate were used to study the flow system of shallow groundwater and soil water at the base area of a former leaching heap at the uranium mining area of ronneburg germany the flow paths and water retention times were estimated by comparison of 2h and 18o values in groundwater and soil water to the 2h and 18o signature of precipitation giving distinctive inputs of summer or winter precipitation the points of measuring the groundwater were divided into three categories with different flow conditions rapid flow stagnant conditions and a transition zone by hierarchical cluster analysis of 2h and 18o values of groundwater the transit time of groundwater in the rapid flow area is less than 6 months whereas water in the stagnant zone is stored for at least 1 year in soil water a clear response to different input signals is detectable only in the 30 cm horizon retention time is about 6 months whereas at deeper levels a mixing with older water is taking place the isotopic composition of the dissolved sulphate was used to identify oxidation of sulphides as the source of sulphate copyright 2010 john wiley sons ltd

an unusual jokulhlaup resulting from subglacial volcanism solheimajokull iceland jokulhlaups glacial outburst floods are frequent in glaciated terrain jokulhlaups exhibiting a sudden rise to peak discharge have not been subject to detailed investigation a volcanically generated flood burst from solheimajokull iceland in july 1999 this paper accounts for the causes characteristics and impacts of this flood pre and post flood fieldwork was carried out at solheimajokull allowing the reconstruction of mean flow velocities and peak discharge flood onset was rapid rising to a peak discharge of 4 4 x 103 m3s 1 1 2 x 103 m3s 1 within one hour high basal water pressures resulted in floodwater bursting through the glacier surface ice rip up clasts containing glacial diamict provided evidence of floodwater contact with the glacier bed within the glacier jokulhlaup sedimentation occurred within hydrofractures and conduits generating complex hydrofracture fills and esker ridges in the proglacial zone regions of flow expansion associated with rapid reductions in sediment transport capacity controlled the locations of major jokulhlaup sedimentation a large fan composed of material of up to boulder size was deposited at the glacier snout two ice marginal basins filled and drained during the jokulhlaup one of the basins jokulsargil emptied rapidly during the flood via ice dam flotation accentuating peak jokulhlaup discharge high rates of downstream peak discharge attenuation during the july 1999 jokulhlaup provides an analogy with flash flood hydrographs in semi arid regions and the catastrophic failure of man made dams the july 1999 jokulhlaup was initially triggered by the subglacial volcanic eruption but the characteristics of the flood were accentuated by within event meltwater storage and release this unusual jokulhlaup provides an important addition to our understanding of the spectrum of distinctive jokulhlaup characteristics

sulfur isotope evidence for changing input of continental and marine aerosols in a 60 000 year sediment core from lake tulane central florida usa variations in sulfur isotope ratios in lacustrine sediments are used here to reveal regional aspects of past environmental change at lake tulane florida usa earlier studies of this late pleistocene holocene lake sediment core provided the framework for assessing some of the underlying mechanisms of change in the paleolimnology of lake tulane prior research on the lake s history identified seven phases of pinus dominated vegetation interpreted as periods with warm and wet climate intervening times were relatively cool and dry we hypothesized that variations in vegetation and climate along with deepening of the lake might lead to temporal changes in s cycling and in 34s of sulfur delivered to the sediment the stratigraphy is characterized by a wide range of 34s values 7 to 15 v cdt and a sequence of four major extended trends in 34s within the 60 000 year period changes in the 34s profile were statistically unrelated to five tested parameters concentrations of s organic matter al and fe and local vegetation total sulfur concentration was positively correlated with organic matter pyrite was not detected the 34s trends were more likely related to changes in the distance to sources of marine aerosols during the late pleistocene and holocene flux of marine aerosols with more positive 34s would have been lowest at the last glacial maximum about 20 25 000 cal yr bp when sea level was at least 120 m lower than present and the shorelines east and west of florida were as much as 200 km seaward of the modern position the 34s lake sediment profile thus provides insights into past paleogeographic changes that are not evident in other geochemical or palynological data

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

spatial variations in water composition at a northern canadian lake impacted by mine drainage abstract release of acid drainage from mine waste disposal areas is a problem of international scale contaminated surface water derived from mine wastes orginates both as direct surface runoff and indirectly as subsurface groundwater flow at camp lake a small canadian shield lake that is in northern manitoba and is ice covered 6 months of the year direct and indirect release of drainage from an adjacent sulfide rich tailings impoundment has severely affected the quality of the lake water concentrations of the products from sulfide oxidation are extremely high in the pore waters of the tailings impoundment groundwater and surface water derived from the impoundment discharge into a semi isolated shallow bay in camp lake the incorporation of this aqueous effluent has altered the composition of the lake water which in turn has modified the physical limnology of the lake geochemical profiles of the water column indicate that despite its shallow depth 6 m the bay is stratified throughout the year the greatest accumulation of dissolved metals and so 4 is in the lower portion of the water column with concentrations up to 8500 mg l 1 fe 20 000 mg l 1 so 4 30 mg l 1 zn 100 mg l 1 al and elevated concentrations of cu cd pb and ni meromictic conditions and very high solute concentrations are limited to the bay outside the bay solute concentrations are lower and some stratification of the water column exists identification of locations and composition of groundwater discharge relative to lake bathymetry is a fundamental aspect of understanding chemical evolution and physical stability of mine impacted lakes