selection of earthquake scaling relationships for seismic hazard analysis a fundamentally important but typically abbreviated component of seismic hazard analysis is the selection of earthquake scaling relationships these are typically regressions of historical earthquake datasets in which magnitude is estimated from parameters such as fault rupture length and area the mix of historical data from different tectonic environments and the different forms of the regression equations can result in large differences in magnitude estimates for a given fault rupture length or area we compile a worldwide set of regressions and make a first order shortlisting of regressions according to their relevance to a range of tectonic regimes plate tectonic setting and fault slip type in existence around the world regression relevance is based largely on the geographical distribution age and quantity quality of earthquake data used to develop them our compilation is limited to regressions of magnitude or seismic moment on fault rupture area or length and our shortlisted regressions show a large magnitude range up to a full magnitude unit for a given rupture length or area across the various tectonic regimes these large differences in magnitude estimates underline the importance of choosing regressions carefully for seismic hazard application in different tectonic environments

rates of late quaternary normal faulting in central tibet from u series dating of pedogenic carbonate in displaced fluvial gravel deposits along the main boundary fault of the central tibetan shuang hu graben two well preserved fluvial terrace surfaces are vertically offset by 1 3 m terrace i and 14 8 m terrace ii using thermal ionization mass spectrometry tims we have determined 48 230th 234u 238u ages of small 10 40 mg samples from pedogenic carbonate rinds on clasts in the terrace deposits based on textural microstratigraphic and geochemical criteria we conclude that the u series ages of innermost rind samples provide reliable ages of 16 4 1 9 ka for terrace i and 233 1 9 3 ka for terrace ii this constrains the average rate of vertical displacement along the normal fault to be 0 079 0 011 mm yr during the past 16 kyr and 0 064 0 007 mm yr during the past 233 kyr combining these results with slip rate estimates for other normal faults along the graben margins indicates that the cumulative vertical displacement on all normal faults did not exceed 0 3 mm yr during the late quaternary this new rate from central tibet is distinctly lower than the rate of 1 9 0 6 mm yr inferred for normal faults bounding the yadong gulu graben system in southern tibet consistent with more pronounced and common graben development in southern tibet we therefore suggest that normal faulting in southern tibet is largely controlled by local processes and that the age of its initiation is not a valid proxy for uplift of the tibetan plateau as has been widely assumed our data also place chronologic constraints on the termination of periglacial conditions in central tibet during the last three interglaciations rind formation appears to have been relatively continuous on clasts in terrace i from 16 ka clast rinds from terrace ii in contrast are characterized by three main episodes of rind growth that are widely separated in time the earliest and least well preserved episode started at 233 1 9 3 ka a second episode occurred at 131 8 7 8 ka and a third episode was approximately coeval with rind formation in terrace i after 16 4 1 9 ka in each case the age of onset of carbonate rind accumulation coincides with independently estimated ages of global deglaciation accordingly we conclude that periglacial conditions in the central tibetan plateau terminated synchronously with early stages of global warming following the last three glacial maxima and that fluvial aggradation terrace formation and pedogenic carbonate accumulation in terrace soils ensued rapidly

late quaternary paleoseismology of the milin fault implications for active tectonics along the yarlung zangbo suture southeastern tibet plateau abstract how the eastward motion of crust in the central tibetan plateau is accommodated in the remote regions of the eastern himalayan syntaxis remains uncertain although the yarlung zangbo suture yzs forms a striking lineament in the topography of the region evidence for recent faulting along this zone has been equivocal to understand whether faults along the yzs are active we performed a geological investigation along the eastern segments of the yzs geomorphic observations suggest the presence of active faulting along several segments of the yzs which we collectively refer to as the milin fault paleoseismologic data from trenches reveal evidence for one faulting event which is constrained to occur between 5620 and 1945 a bp the latest faulting event displaced alluvial surface t2 by 7 m the offset on this earthquake place the minimum value on the vertical slip rate of 0 3 mm yr empirical relationships between surface rupture length displacement and magnitude suggest that magnitude of the latest event could have been mw 7 3 7 7 on the basis of this slip rate and the elapsed time since the last event it is estimated that a seismic moment equivalent to mw 7 0 has been accumulated on the milin fault it is pose a threat to the surrounding region our results suggest that shortening occurs in the vicinity of the eastern himalayan syntaxis and part of eastward motion of crust from the central tibetan plateau is absorbed by uplift of the eastern himalayan syntaxis

miocene jiali faulting and its implications for tibetan tectonic evolution the karakoram jiali fault zone kjfz comprises a series of right lateral shear zones that southerly bound the eastward extrusion of northern tibet relative to india and stable eurasia here we present new 40 ar 39 ar age data from the puqu and parlung faults two easternmost branches of the jiali fault zone which indicate a main phase of the kjfz shearing from v18 to 12 ma thus the tibetan eastward extrusion bounded by principal strike slip fault zones started and was probably most active around the middle miocene an interval marked also by active east west extension in southern tibet the coincidence of these two tectonic events strongly suggests a common causal mechanism which is best explained as oblique convergence between india and asia under the framework of this mechanism the extension in southern tibet is not a proxy for the plateau uplift the kjfz activity was furthermore coincident with right lateral displacements along the gaoligong and sagaing faults in southeast asia this defines a miocene deformation record for the regional dextral accommodation zone that in response to the continuing india asia collision may have accounted for the initiation and prolonged history of clockwise rotation of the tibetan extrusion around the eastern himalayan syntaxis 2002 elsevier science b v all rights reserved

significant late neogene east west extension in northern tibet field mapping in northern tibet reveals that the normal slip along late cenozoic northsouth trending faults is comparable to that estimated for equivalent structures in southern tibet the orientation of fault striations in two north south trending rifts suggests an eastnortheast west northwest direction of extension in northern tibet which in turn implies that northeast striking active faults in northern tibet have significant left slip components initiation of rifting in northern tibet postdates the early oligocene and possibly occurred after 4 ma the broad similarities in the magnitude of slip and the direction of extension for normal faults in both northern and southern tibet imply that the entire plateau has been extending this precludes significant eastward extrusion of north tibet relative to south tibet and requires a regional boundary condition as the cause of east west extension for the entire tibet plateau

tectonic control of yarlung tsangpo gorge revealed by a buried canyon in southern tibet the himalayan mountains are dissected by some of the deepest and most impressive gorges on earth constraining the interplay between river incision and rock uplift is important for understanding tectonic deformation in this region we report here the discovery of a deeply incised canyon of the yarlung tsangpo river at the eastern end of the himalaya which is now buried under more than 500 meters of sediments by reconstructing the former valley bottom and dating sediments at the base of the valley fill we show that steepening of the tsangpo gorge started at about 2 million to 2 5 million years ago as a consequence of an increase in rock uplift rates the high erosion rates within the gorge are therefore a direct consequence of rapid rock uplift

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

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

pyrite framboids interpreted as microbial colonies within the permian zoophycos spreiten from southeastern australia two types of pyrite framboids pf probably sulphate reducing bacteria have been found within the zoophycos spreiten hosted in the guadalupian middle permian glaciomarine greywacke of the westley park sandstone member within the broughton formation from the southern sydney basin of southeastern australia they are composed of non sheathed pf1 and sheathed pf2 sub micron balls respectively chemically the sub micron balls consist of iron sulphur carbon and oxygen both pf1 and pf2 occur in rhythmic alternation within the thick light grey and thin dark grey minor lamellae of zoophycos spreiten the framboids from the minor lamellae are highly abundant and occur in an orderly arrangement of equal density and in a good state of preservation within zoophycos spreiten no homogeneous filling fecal pellets or any sign of re exploitation of the minor lamellae have been recognized no similar framboids have been observed outside zoophycos spreiten therefore the framboids are interpreted as the pyritized remains of microbial colonies within zoophycos spreiten the trace zoophycos would be a multifunctional garden that may have been carefully constructed by the zoophycos maker where different microbial colonies were orderly and carefully planted and cultured within different minor lamellae further it is proposed that the zoophycos maker had a symbiotic relationship with microbial colonies on the mutual basis of food supply and redox conditions the fact that the overlying spreiten cut the underlying ones indicates that the zoophycos from the study area is of an upward construction the rhythmic alternation of both the thick light grey and thin dark grey minor lamellae within zoophycos spreiten may be suggestive of a gardening manner of the zoophycos maker responding to the warm and cold changes food supply in pulses and variations of sedimentation rate for planting and culturing microbial colonies under the conditions of a glaciomarine environment at the high latitudes

broadscale interseismic deformation and fault slip rates in the central tibetan plateau observed using insar 1 knowledge of the number location and interseismic slip rate of crustal faults is key to our understanding of the bulk mechanics of continental deformation however at present the sparsity of geodetic velocity observations is a major limiting factor to improving our knowledge of the fault network in this study we combine long swath interferometric synthetic aperture radar insar data to form an interseismic displacement rate map of over 1000 km length spanning the central tibetan plateau our dense geodetic observations indicate that strain varies smoothly in space without major concentration at previously mapped faults discrepancy between line of sight insar and gps observations between 33 n 35 n could indicate 4 mm yr of surface uplift in this region derived strain rates are less than 5 10 8 yr 1 across the plateau at the e w left lateral kunlun fault postseismic deformation following the 2001 kokoxili earthquake results in an observed strain rate of 18 4 10 8 yr 1 across a 100 km wide zone following removal of a viscoelastic model we estimate an interseismic slip rate of 12 2 mm yr for the kunlun fault in the central tibetan conjugate fault zone the ne sw striking amdo sewa and nw se striking beng co faults have right lateral slip rates of 6 1 mm yr and 1 4 1 mm yr respectively meanwhile the ne sw striking dongqiao fault has a left lateral slip rate of 1 2 1 mm yr the low slip rates we estimate for these faults indicate that tectonic strain is more broadly distributed across the plateau interior perhaps due to the lithosphere being weak and without the abrupt strength contrasts that exist at the plateau margins

mechanics of v shaped conjugate strike slip faults and the corresponding continuum mode of continental deformation v shaped conjugate strike slip faults occur widely on earth venus and mars in the solar system they commonly lie at 60 75 in map view from the maximum compressive stress 1 direction this fault pattern cannot be explained directly by the coulomb fracture criterion which predicts the formation of x shaped shear fractures at 30 from the 1 direction possible explanations of this odd fault geometry include rotation of early formed coulomb fractures or reactivation of preexisting weakness here we show that none of these mechanisms is feasible for the formation of a late cenozoic conjugate strike slip fault system in central tibet instead its initiation can be best explained by distributed deformation during the formation of two parallel and adjoining shear zones that have opposing senses of shear our suggestion is based on the current global positioning system gps velocity field in tibet which can be divided into two east trending shear zones a northern left slip zone consisting of active ene striking left slip faults and a southern right slip zone consisting of active wnw striking right slip faults the correlation between the gps strain field and the fault pattern suggests that the central tibet conjugate faults may have initiated as two sets of riedel shears in the two parallel but separate shear zones because the two east trending shear zones also experience north south contraction we refer to this mechanism of conjugate fault formation as paired general shear pgs deformation assuming a newtonian fluid the observed tibetan gps velocity field requires the paired shear zones to have formed either by gravitational spreading of the tibetan lithosphere or a horizontal shear at the base of the upper crust or mantle lithosphere we demonstrate the feasibility of the two inferred mechanisms for the formation of v shaped conjugate faults using simple sandbox experiments our paired general shear pgs model implies that the combined effect of the state of strain and the state of stress favors only one set i e riedel shear of coulomb conjugate shear fractures under general shear flow it also requires continuum deformation rather than discrete extrusion tectonics as the most dominant mode of deformation during the late cenozoic development of the central tibetan plateau

new empirical relationships among magnitude rupture length rupture width rupture area and surface displacement source parameters for historical earthquakes worldwide are compiled to develop a series of empirical relationships among moment magnitude m surface rupture length subsurface rupture length downdip rupture width rupture area and maximum and average displacement per event the resulting data base is a significant update of previous compilations and includes the additional source parameters of seismic moment moment magnitude subsurface rupture length downdip rupture width and average surface displacement each source parameter is classified as reliable or unreliable based on our evaluation of the accuracy of individual values only the reliable source parameters are used in the final analyses in comparing source parameters we note the following trends 1 generally the length of rupture at the surface is equal to 75 of the subsurface rupture length however the ratio of surface rupture length to subsurface rupture length increases with magnitude 2 the average surface displacement per event is about one half the maximum surface displacement per event and 3 the average subsurface displacement on the fault plane is less than the maximum surface displacement but more than the average surface displacement thus for most earthquakes in this data base slip on the fault plane at seismogenic depths is manifested by similar displacements at the surface log linear regressions between earthquake magnitude and surface rupture length subsurface rupture length and rupture area are especially well correlated showing standard deviations of 0 25 to 0 35 magnitude units most relationships are not statistically different at a 95 significance level as a function of the style of faulting thus we consider the regressions for all slip types to be appropriate for most applications regressions between magnitude and displacement magnitude and rupture width and between displacement and rupture length are less well correlated and have larger standard deviation than regressions between magnitude and length or area the large number of data points in most of these regressions and their statistical stability suggest that they are unlikely to change significantly in response to additional data separating the data according to extensional and compressional tectonic environments neither provides statistically different results nor improves the statistical significance of the regressions regressions for cases in which earthquake magnitude is either the independent or the dependent parameter can be used to estimate maximum earthquake magnitudes both for surface faults and for subsurface seismic sources such as blind faults and to estimate the expected surface displacement along a fault for a given size earthquake

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

three dimensional velocity field of present day crustal motion of the tibetan plateau derived from gps measurements 1 using the measurements of 750 gps stations around the tibetan plateau for over 10 years since 1999 we derived a high resolution 3 d velocity field for the present day crustal movement of the plateau the horizontal velocity field relative to stable eurasia displays in details the crustal movement and tectonic deformation features of the india eurasia continental collision zone with thrust compression lateral extrusion and clockwise rotation the vertical velocity field reveals that the tibetan plateau is continuing to rise as a whole relative to its stable north neighbor however in some subregions uplift is insignificant or even negative the main features of the vertical crustal deformation of the plateau are the following a the himalayan range is still rising at a rate of 2 mm yr the uplift rate is 6 mm yr with respect to the south foot of the himalayan range b the middle eastern plateau has a typical uplift rate between 1 and 2 mm yr and some high mountain ranges in this area like the longmen shan and gongga shan have surprising uplift rates as large as 2 3mm yr c in the middle southern plateau there is a basin and endorheic subregion with a series of ns striking normal faults showing obvious sinking with the rates between 0 and 3 mm yr d the present day rising and sinking subregions generally correspond well to the cenozoic orogenic belts and basins respectively e at the southeastern corner of the plateau there is an apparent trend that the uplift rate is gradually decreasing from between 0 8 and 2 3 mm yr in the inner plateau to between 0 5 and 1 6 mm yr outside the plateau with the decrease of terrain height

spatially variable extension in southern tibet based on gps measurements 1 we use global positioning system gps data and kinematic block models to study the present day deformation of southern tibet gps data from 33 sites in southern tibet and nepal surveyed between 1991 and 2000 reveal 13 2 mm yr of n110 e extension between lhasa and shiquanhe 80 e 91 e of which 9 7 3 0 mm yr represents permanent extension of the tibetan crust the remaining 3 mm yr results from elastic deformation from the locked curving main himalayan thrust fault this extension is spatially nonuniform one half to two thirds of the permanent extension is concentrated across the yadong gulu rift with an opening rate of 6 5 1 5 mm yr most of the remainder occurs on or near the thakkola graben with little extension across the rifts between them differential velocities of sites north and south of the yarlung zangbo suture in western tibet imply that the suture or an adjacent structure may be active as a strike slip fault a numerical model suggests that right lateral strike slip on the yarlung zangbo suture may extend from the karakorum fault zone in the west at least to the yadong gulu rift in the east with 3 mm yr slip rate accommodating part of the eastward extrusion of tibet the convergence directions inferred from gps are consistent with slip vectors of earthquakes however the rate of slip of india beneath tibet along the himalaya is lower than those previously estimated we estimate a slip rate of 12 4 0 4 mm yr between longitudes 83 e and 88 e and 17 1 and 19 1 mm yr in the western and eastern himalaya respectively the variable slip rate correlates with the variable extension rate in southern tibet and we suggest that it results from variation in the deformation rate of the overriding tibetan crust we infer that the slower convergence rate in the central himalaya is significant

present day crustal motion within the tibetan plateau inferred from gps measurements 1 using the measurements of 726 gps stations around the tibetan plateau we determine the rigid rotation of the entire plateau in a eurasia fixed reference frame which can be best described by an euler vector of 24 38 0 42 n 102 37 0 42 e 0 7096 0 0206 ma the rigid rotational component accommodates at least 50 of the northeastward thrust from india and dominates the eastward extrusion of the northern plateau after removing the rigid rotation to highlight the interior deformation within the plateau we find that the most remarkable interior deformation of the plateau is a glacier like flow zone which starts at somewhere between the middle and western plateau goes clockwise around the eastern himalayan syntaxis ehs and ends at the southeast corner of the plateau with a fan like front the deformation feature of the southern plateau especially the emergence of the flow zone could be attributed to an eastward escape of highly plastic upper crustal material driven by a lower crust viscous channel flow generated by lateral compression and gravitational buoyancy at the later developmental stage of the plateau the first order feature of crustal deformation of the northeastern plateau can be well explained by a three dimensional elastic half space dislocation model with rates of dislocation segments comparable to the ones from geological observations in the eastern plateau although gps data show no significant convergence between the eastern margin of the plateau and the sichuan basin a small but significant compressional strain rate component of 10 5 2 8 nstrain yr exists in a relatively narrow region around the eastern margin in addition a large part of the eastern plateau northeast of the ehs is not undergoing shortening along the northeastward convergence direction of the ehs but is stretching

growth of the namche barwa syntaxis and associated evolution of the tsangpo gorge constraints from structural and thermochronological data abstract the eastern syntaxis of the himalaya namche barwa is dominated by a north plunging antiform which began to decompress grow at approximately 4 ma new fission track analyses on both apatite and zircon combined with previous geochronological ages indicate that the namche barwa dome also extended laterally while growing vertically zircon fission track ages range from 17 6 to 0 2 ma and have a strong relationship to the main faults of the region including the tertiary tsangpo suture with the younger ages inside the fault bounds towards the syntaxis core on the indian plate and the older ages away from the fault apatite ages reveal that the dome has grown laterally and now impinges over the older faulted margin onto the asian plate the dome is traversed by the tsangpo which has followed the trace of the suture for over 1300 km from its source to the entrance of the dome near dania as the tsangpo crosses the dome it departs from the suture but rejoins it some 60 km northeastwards we construe that the suture has been displaced by the growing antiform and as a consequence the antecedent river has been dragged in a left lateral sense along the exhuming north plunging dome restoring the suture to its position prior to 4 ma reveals a path of the tsangpo eastwards across the present southwestern position of the namche barwa indentation this geometric reconstrunction implies that the tsangpo and the brahmaputra were always one and the same river in addition the tsangpo was tectonically forced into juxtaposition with a tributary of the jiali parlung which it probably then captured the capture was due to tectonic forcing in the last 4 ma rather than headward retreat of the paleo brahmaputra as has been previously suggested

intraseasonal variability of high resolution doppler imager winds in the equatorial mesosphere and lower thermosphere analyses of high resolution doppler imager hrdi daytime equatorial zonal winds indicate significant variability on time scales of 20 121 days these appear as transient oscillations in the equatorial zonal mean zonal wind between 70 and 100 km the oscillations are characterized by two maxima near 75 and 95 km that are out of phase separated by a minimum near 80 km these features move downward in time and exhibit equatorial symmetry with maximum values at the equator during 1994 maximum amplitudes of the intraseasonal oscillation are 20 m s 1 in january and 30 m s 1 in june the intraseasonal variability present in hrdi winds is qualitatively consistent with variations on similar timescales reported at christmas island it has been hypothesized that the wind patterns at christmas island result from modulated gravity wave driving eckermann et al 1997 the results of the present study strongly support this view

the properties of reservoir water in post mining excavations of cambrian and devonian quartzite sandstones holy cross mountains in the holy cross mountains southern poland there are numerous disused quarries some of these are filled with water and some despite their nearby location have extremely diverse physicochemical and chemical properties of their waters one such object is the wi niowka mala reservoir its waters contain large amounts of sulfates 700 mg l and iron 24 mg l which are weathering products of rocks containing metal sulfides mainly pyrite in the direct drainage zone as a consequence there is an increase in the electrolytic conductivity of the water supplying the reservoir resulting in very low ph values 4 this article presents the detailed limnological characteristics of this reservoir and explains the process that led to its water acidification a control reservoir barcza was also selected for the tests although it is also a post mining excavation it has a neutral ph and a low concentration of sulfates and iron the examined reservoirs differ in the hydrochemical type of waters the wi niowka mala reservoir represents a sulfate calcium double ion type so42 ca2 and the barcza reservoir a bicarbonate calcium type hco3 ca2 the concentrations of the main ions occurring here are shaped by the lithological features of the surrounding rocks respectively upper cambrian quartzite sandstones with pyrite mineralization zones lower devonian sandstones cut by mudstones and claystones with tuffite inserts

sources of environmental sulfur in the groundwater system southern new zealand abstract sulfide minerals commonly occur in sediments and basement rocks in southern new zealand as authigenic precipitates from groundwater below the oxygenated surface zone there are two principal potential sources for sulfur in the groundwater system weathering of sulfide minerals in the metamorphic basement and rainwater derived marine aerosols we present data for these two key sulfur sources metamorphic sulfide and associated hydrothermal au bearing veins within the otago schist average 34s 1 8 2 4 and an inland saline lake s derived entirely from rainwater 34s 21 4 0 8 we use these two end member 34s values to estimate the contributions of these sources of sulfur in authigenic groundwater sulfide minerals and in waters derived from oxidation of these sulfide minerals across a range of environments we show that authigenic groundwater pyrite along joints in the otago schist is derived primarily from metamorphic basement sulfur in contrast authigenic groundwater pyrite cementing miocene recent aquifers shows a substantial marine aerosol component and represents a distinct hydrogeological system we suggest that marine aerosols represent a significant flux to the terrestrial sulfur cycle that has been present through the groundwater system in otago over the past 20 million years

hydrogeochemical processes governing the origin transport and fate of major and trace elements from mine wastes and mineralized rock to surface waters abstract the formation of acid mine drainage from metals extraction or natural acid rock drainage and its mixing with surface waters is a complex process that depends on petrology and mineralogy structural geology geomorphology surface water hydrology hydrogeology climatology microbiology chemistry and mining and mineral processing history the concentrations of metals metalloids acidity alkalinity cl f and so 4 2 found in receiving streams rivers and lakes are affected by all of these factors and their interactions remediation of mine sites is an engineering concern but to design a remediation plan without understanding the hydrogeochemical processes of contaminant mobilization can lead to ineffective and excessively costly remediation furthermore remediation needs a goal commensurate with natural background conditions rather than water quality standards that might bear little relation to conditions of a highly mineralized terrain this paper reviews hydrogeochemical generalizations primarily from us geological survey research that enhance our understanding of the origin transport and fate of contaminants released from mined and mineralized areas mobility of potential or actual contaminants from mining and mineral processing activities depends on 1 occurrence is the mineral source of the contaminant actually present 2 abundance is the mineral present in sufficient quantity to make a difference 3 reactivity what are the energetics rates and mechanisms of sorption and mineral dissolution and precipitation relative to the flow rate of the water and 4 hydrology what are the main flow paths for contaminated water estimates of relative proportions of minerals dissolved and precipitated can be made with mass balance calculations if minerals and water compositions along a flow path are known combined with discharge these mass balance estimates quantify the actual weathering rate of pyrite mineralization in the environment and compare reasonably well with laboratory rates of pyrite oxidation except when large quantities of soluble salts and evaporated mine waters have accumulated underground quantitative mineralogy with trace element compositions can substantially improve the identification of source minerals for specific trace elements through mass balances post dissolution sorption and precipitation attenuation reactions depend on the chemical behavior of each element solution composition and ph aqueous speciation temperature and contact time with mineral surfaces for example little metal attenuation occurs in waters of low ph

quaternary extension in southern tibet field observations and tectonic implications we summarize evidence for quaternary and active faulting collected in the field during three sino french expeditions to southeastern tibet 1980 1982 detailed mapping of quaternary and active faults as well as microtectonic measurements indicate that normal faulting has been the dominant tectonic regime north of the himalayas in the last 2 0 5 m y the maximum horizontal principal stress in south tibet appears to be only the intermediate principal stress 2 1 being vertical south of the chord joining the eastern and western syntaxes of the himalayan arc extensional strains are principally localized within seven regularly spaced rift zones three of which have been studied in some detail the extension direction is determined to be n96 e 7 mainly from statistical averaging of strikes of newly formed normal faults throw rates on normal faults are evaluated for different time spans 2 0 5 m y 60 40 kyr and 10 2 kyr b p using structural and topographic reliefs as well as synglacial and postglacial vertical offsets the rate of quaternary extension is about 1 m y 1 along an 1100 km long ese traverse across south tibet this corresponds to a spreading rate of 1 0 6 cm yr this rate and the divergent horizontal projections of slip vectors of earthquakes along the himalayan front constrain the rate at which rigid india underthrusts southern tibet to be 2 1 cm yr although most of the normal faults appear to be independent of and nearly orthogonal to the e w mesozoic tertiary tectonic fabric the yadong gulu rift appears to be guided for over 130 km by the older oblique ne sw nyainqentanglha range and fault zones along it this reactivated zone is the most prominent left lateral strike slip fault system in se tibet excepting this zone and the vicinity of the se extremity of the karakorum fault quaternary strike slip faulting is rare in south tibet i e south of the chord between the syntaxes of the himalayan arc north of the chord the tectonic style is different there minor conjugate strike slip faulting is widespread and appears to control quaternary normal faulting which is more diffuse and subdued than in south tibet along the chord the presence of a major zone of active right lateral en echelon strike slip faults karakorum jiali fault zone probably reflects the greater facility of eastward extrusion in north central tibet in response to the northward push of india the eastern himalayan syntaxis may be an obstacle to such extrusion movements south of the chord

hydrochemical and stable isotope indicators of pyrite oxidation in carbonate rich environment the hamersley basin western australia abstract sulphur s is a commonly occurring element in most aquifers primarily in oxidised sulphates and reduced sulphides forms sulphides often constitute a risk to groundwater quality due to acid rock drainage especially in catchments that are subject to mining excavations or groundwater injection however in semi arid regions detection of the acid rock drainage risk can be challenging and traditional methods based on observations of increasing so 4 concentrations or so 4 cl ratios in surface and groundwater are not necessarily applicable in addition decreasing ph usually accompanying pyrite oxidation can be masked by the high ph neutralisation capacity of carbonate and silicate minerals analysis of 73 surface and groundwater samples from different water bodies and aquifers located in the hamersley basin western australia found that most of the samples are characterised by neutral ph but there was also a large spatial variability in the dissolved sulphate so 4 concentrations that ranged from 1 mg l to 15 000 mg l not surprisingly groundwater in aquifers that contained pyrite had high sulphate concentrations 1000 mg l this was associated with low 34 s so4 values 1 2 to 4 6 and was consistent with the values obtained from aquifer matrix pyritic rock samples 1 9 to 4 4 it was also found that the so 4 concentrations and acidity levels were not only dependent on 34 s so4 values and existence of pyrite but also on the presence of carbonate minerals in the aquifer matrix the groundwater in aquifers containing both pyrite and carbonate minerals had a neutral ph and was also saturated with respect to gypsum and had high magnesium concentrations of up to 2200 mg l suggesting de dolomitisation as the process buffering the acidity generated by pyrite oxidation based on the findings from this study a classification scheme has been developed for identification of the acid rock drainage contribution to groundwater that encompasses a myriad of geochemical processes that occur in aqueous systems the classification uses five proxies so 4 so 4 cl si of calcite 34 s so4 and 18 o so4 to improve assessment of the oxidation of sulphide potential contribution to overall sulphate ion concentrations regardless of acidity levels of the aqueous system

estimating surface rupture length and magnitude of paleoearthquakes from point measurements of rupture displacement we present a method to estimate paleomagnitude and rupture extent from measurements of displacement at a single point on a fault the variability of historic ruptures is summarized in a histogram of normalized slip then scaled to give the probability of finding a given displacement within a rupture for any magnitude considered the histogram can be inverted assuming any magnitude earthquake is as likely as another yielding probability density functions of magnitude and rupture length for any given displacement measurement to improve these distributions we include a term to account for the probability that the earthquake would cause ground rupture and two alternative distributions of earthquake magnitude the gutenberg richter magnitude distribution predicts shorter rupture lengths and smaller magnitudes than does a uniform distribution where any magnitude earthquake is considered equally likely longer ruptures and larger magnitudes than the uniform model are predicted by an alternative magnitude distribution designed to return site average displacement this model is a generalization of the characteristic earthquake model and reasonably describes paleoseismic findings on the southern san andreas fault where slip is accommodated by average displacements of a few meters and earthquake recurrence times of 100 250 years our results should increase the value of paleoseismic displacement measurements for hazard assessment in particular they quantify probability estimates of earthquake magnitude and rupture length where point observations of rupture displacement are available and so can contribute to probabilistic seismic hazard analyses online material rupture profiles used to sample rupture variability

using stable isotopes s o of sulfate to track local contamination of the madison karst aquifer montana from abandoned coal mine drainage abstract the stockett centerville area south of great falls montana was extensively mined for coal in the late 1800s through the early 1950s after closure the underground mine portals were sealed and the workings became partially flooded the coal seams are rich in pyrite and many of the mines have horizontal drains that are point sources of acid mine drainage amd which flow into dry streambeds and soak into the ground the mississippian madison limestone is located stratigraphically below the coal and is an important source of drinking water twenty six domestic water wells completed in the madison near the former coal mines were sampled for water chemistry and stable isotope analysis of water and dissolved so 4 2 madison aquifer groundwater plots close to the meteoric water line and reveals no clear evidence of mixing with water from the mine drains the latter being slightly enriched in 18o by evaporation in contrast dissolved so 4 2 in the wells has isotopic compositions that suggest mixing from three end member sources 1 regional madison aquifer groundwater with moderate so 4 2 concentrations 110 150 mg l that is isotopically enriched 34s 20 18o 14 2 amd water with very high so 4 2 concentrations 1 9 g l that is isotopically depleted 34s 15 18o 11 and 3 local recharge water with low so 4 2 concentrations so 4 2 derived from amd is estimated to range from 0 to nearly 80 wells with the highest proportion of amd so 4 2 have higher so 4 2 concentrations but otherwise show no mining associated water quality problems such as low ph or elevated concentrations of trace metals underscoring the ability of the madison aquifer to buffer water quality most of the wells with evidence of amd incursion are older wells that were not cased over their entire depth it is possible that the open hole method of completion has allowed some amd related water to infiltrate by gravity to the lower madison aquifer in this study stable isotopes of so 4 2 proved to be a more powerful and sensitive tool to track amd contamination compared to stable isotopes of water or conventional water quality sampling

finite strain calculations of continental deformation 2 comparison with the india asia collision zone numerical experiments on a thin viscous sheet model for deformation of continental lithosphere subjected to an indenting boundary condition yield distributions of crustal thickness of stress and strain rate and of latitudinal displacements that may be compared with observations in the india asia collision zone a simple indenting boundary condition applied to initially laterally homogeneous sheets obeying a power law rheology produces results that are in broad agreement with the observations provided that the power law exponent is three or greater and the sheet can support vertically integrated stress differences of 2 1013 5 1012 n m 1 in regions in front of the indenter under these conditions the calculated deformation shows accommodation of convergence primarily by crustal thickening to produce a plateau in front of the indenter palaeomagnetic data from india and tibet and the observed distribution of topography suggest that much of the post eocene convergence of india with asia has been taken up by deformation within asia that involved crustal thickening the principal difference between calculation and observation is the absence from the calculated strain rate fields of east west extension of the plateau in front of the indenting boundary the calculations show that once such a plateau is formed the buoyancy force associated with the crustal thickness contrast inhibits further thickening and the plateau strains at less than half the rate of its immediate surroundings seismically determined regional strain rates exhibit a similar distribution with the tibetan plateau straining at about one quarter the rate of the tien shan and ningxia gansu regions calculated principal compressive stress orientations and regional strain rates agree with the seismically determined quantities in the mongolia baikal tien shan tibet and ningxia gansu regions of asia to within the uncertainty of the latter the vertically integrated stresses that are calculated for the viscous sheet are comparable with those that can be supported by a theologically stratified continental lithosphere obeying laboratory determined flow laws we suggest that the thin viscous sheet model described in this paper and its companion gives a simple and physically plausible description of the observed deformation in central asia in this description the predominant mechanism of accommodation of continental convergence is diffuse crustal thickening with shear on vertical planes playing a subsidiary role once large crustal thickness contrasts have been established

differential late cenozoic uplift across the dongjiu milin fault zone in the eastern himalayan syntaxis revealed by low temperature thermochronology abstract the eastern himalayan syntaxis ehs as one of the most tectonically active regions on the earth is one of the best places to explore the relationship between tectonics and surface exhumation process the uplift and exhumation history are often by one of two leading models a stationary or localized tectonic aneurysm or a northeasterly migrating crustal antiform previous researchers have placed great emphasis on the core zone of namche barwa antiform however the dongjiu milin fault zone dmfz which forms the northwestern boundary of the antiform and plays an important role for deformation process in the ehs is still poorly understood in this study we focus on differential late cenozoic uplift across the dmfz we collected 10 bedrock samples in two vertical transects one on the northwest side of the dmfz on the lhasa block and one on the southeast side on the namche barwa antiform and conducted apatite fission track and zircon fission track analyses ten samples collected from the two vertical transects yield aft ages between 3 2 million years ago ma and 10 3 ma and zft ages between 9 9 ma and 12 9 ma a finite element analysis reveals that the two sides of the dmfz have undergone quite different uplift histories and processes in the late cenozoic the lhasa block is uniformly uplifted while the namche barwa antiform is nonuniformly uplifted similar to a buckle fold the phenomenon revealed in this study is best explained by a mechanism whereby the ehs is characterized by the northeasterly migration of an antiform

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

hydrochemistry mineralogy and sulfur isotope geochemistry of acid mine drainage at the mt morgan mine environment queensland australia mineralogical hydrochemical and s isotope data were used to constrain hydrogeochemical processes that produce acid mine drainage from sulfidic waste at the historic mount morgan au cu mine and the factors controlling the concentration of so4 and environmentally hazardous metals in the nearby dee river in queensland australia some highly contaminated acid waters with metal contents up to hundreds of orders of magnitude greater than the australia new zealand environmental standards by pass the water management system at the site and drain into the adjacent dee river mine drainage precipitates at mt morgan were classified into 4 major groups and were identified as hydrous sulfates and hydroxides of fe and al with various contents of other metals these minerals contain adsorbed or mineralogically bound metals that are released into the water system after rainfall events sulfate in open pit water and collection sumps generally has a narrow range of s isotope compositions 34s 1 8 3 7 that is comparable to the orebody sulfides and makes s isotopes useful for tracing so4 back to its source the higher 34s values for no 2 mill diesel sump may be attributed to a difference in the source dissolved so4 in the river above the mine influence and 20 km downstream show distinctive heavier isotope compositions 34s 5 4 6 8 the dee river downstream of the mine is enriched in 34s 34s 2 8 5 4 compared with mine drainage possibly as a result of bacterial so4 reduction in the weir pools and in the water bodies within the river channel the so4 and metals attenuate downstream by a combination of dilution with the receiving waters so4 reduction and the precipitation of fe and al sulfates and hydroxides it is suggested here that in subtropical queensland with distinct wet and dry seasons temporary reducing environments in the river play an important role in s isotope systematics

observation of an ultraslow large scale wave near the tropical tropopause an analysis is made of very high resolution radiosonde data taken at seven western pacific island stations during toga coare tropical ocean global atmosphere and coupled ocean atmosphere response experiment evidence is found for a wave near the tropopause with periods 30 40 days and with very slow 3 m s 1 eastward propagation this oscillation appears quite coherent across the region considered a 37 longitude spread the oscillation has a short vertical wavelength 3 km and is strongly attenuated above the tropopause and thus would be very hard to observe in either satellite data or conventional meteorological analyses

geochemistry and stable isotope composition of the berkeley pit lake and surrounding mine waters butte montana abstract samples of mine water from butte montana were collected for paired geochemical and stable isotopic analysis the samples included two sets of depth profiles from the acidic berkeley pit lake deep groundwater from several mine shafts in the adjacent flooded underground mine workings and the acidic horseshoe bend spring beginning in july 2000 the spring was a major surface water input into the berkeley pit lake vertical trends in major ions and heavy metals in the pit lake show major changes across a chemocline at 10 20 m depth the chemocline most likely represents the boundary between pre 2000 and post 2000 lake water with lower salinity modified horseshoe bend spring water on top of higher salinity lake water below based on stable isotope results the deep pit lake has lost approximately 12 of its initial water to evaporation while the shallow lake is up to 25 evaporated the stable isotopic composition of so 4 in the pit lake is similar to that of horseshoe bend spring but differs markedly from so 4 in the surrounding flooded mine shafts the latter is heavier in both 34 s and 18 o which may be due to dissolution of hypogene so 4 minerals anhydrite gypsum barite in the ore deposit the isotopic and geochemical evidence suggests that much of the so 4 and dissolved heavy metals in the deep berkeley pit lake were generated in situ either by leaching of soluble salts from the weathered pit walls as the lake waters rose or by subaqueous oxidation of pyrite on the submerged mine walls by dissolved fe iii laboratory experiments were performed to contrast the isotopic composition of so 4 formed by aerobic leaching of weathered wallrock vs so 4 from anaerobic pyrite oxidation the results suggest that both processes were likely important in the evolution of the berkeley pit lake

kinematics and dynamics of the namche barwa syntaxis eastern himalaya constraints from deformation fabrics and geochronology abstract field observations deformation and fabric analyses and precise age data acquired by zircon shrimp la icp ms u pb and 40 ar 39 ar dating methods have yielded new constraints on the kinematics and dynamics of the namche barwa syntaxis nbs which is the eastern corner of the himalaya a two stage model has been established to explain the formation and evolution of the nbs the northward indentation of the indian plate beneath the lhasa terrane began at 55 40 ma and crustal materials at this corner were subducted to depths 70 km where they experienced hp uhp metamorphism since 40 ma large scale right lateral strike slip along the sagaing fault has accommodated the rapid northward movement of the eastern indian plate corner with respect to the indochina block this caused significant and progressive bending of the indus yarlung suture zone iysz such that it became the dongjiu milin left lateral strike slip shear zone dmsz in the west and the aniqiao motuo right lateral strike slip shear zone amsz in the east both zones underwent strong mylonitization meanwhile the hp uhp metamorphic rocks were rapidly exhumed first into the deep crust at 22 18 ma and then to the shallow crust to form an antiformal dome at 6 2 ma our model provides new insight into the processes of post collisional crustal thickening related to the formation of the himalayan orogenic belt

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

holocene slip rate along the gyaring co fault central tibet although geodetic measurements of interseismic deformation in interior tibet suggest slow strain accumulation active slip along the right lateral gyaring co fault is suggested to be between 8 and 21 mm yr reliable geologic constraints on the slip rate along this fault are sparse here we document 12 2 m of right lateral displacement of lacustrine shorelines across the gyaring co fault optically stimulated luminescence ages of the shorelines are tightly clustered between 4 1 and 4 4 ka these data require an average slip rate of 2 2 3 2 mm yr along the central gyaring co fault during the latter half of the holocene consideration of seismic cycle effects allows the possibility of slightly higher average slip rates up to 2 2 4 5 mm yr overall our results suggest that the slip rate along the gyaring co fault is similar to other strike slip faults in interior tibet supporting the notion that active deformation in this region is distributed among numerous slowly moving faults

late neoproterozoic to early palaeozoic palaoegeography of the holy cross mountains central europe an integrated approach study of geochemistry examination of isotope ages of detrital minerals palaeomagnetic analysis and a study of the trilobites were performed to provide constraints on the palaeogeographical position of the holy cross mountains in late ediacaran early palaeozoic time the geochemical results indicate an active continental margin or continental island arc provenance of the ediacaran sediments sediments from a passive continental margin were deposited here during the cambrian and ordovician the palaeomagnetic pole isolated from cambrian rocks of the malopolska region of the holy cross mountains corresponds to the cambrian segment of the baltic apparent polar wander path isotope age estimations indicate that cambrian sediments of the malopolska region contain detritus not only from a latest neoproterozoic source but also from sources with ages of c 0 8 0 9 ga 1 5 ga and 1 8 ga the malopolska brunosilesia dobrugea and moesia terranes which originally developed near the present southern edge of baltica and were partly involved in the cadomian orogen were dextrally relocated along its trans european suture zone margin the first stage of this movement took place as early as latest ediacaran time while baltica rotated anticlockwise anticlockwise rotation of baltica at the cambrian ordovician boundary implies further dextral movement of the malopolska block

coupling of rock uplift and river incision in the namche barwa gyala peri massif tibet geodynamic modeling demonstrates the strong potential for erosion to influence the pattern and style of deformation in active mountain belts but field studies yield conflicting views on the importance of erosion in influencing orogenesis here we compare patterns in river power inferred excess fluvial transport capacity topographic relief precipitation and mineral cooling ages to assess the coupling between surface erosion and rock uplift within the vicinity of the namche barwa gyala peri massif an active antiformal structure within the eastern himalayan syntaxis our rich and dense data set reveals a tight spatial correspondence of fluvial incision potential high relief and young cooling ages the spatial coincidence is most easily explained by a sustained balance between rock uplift and denudation driven by river incision over at least the last 1 m y the yarlung tsangpo brahmaputra river is the largest and most powerful river in the himalaya and two lines of evidence point to its active role in the dynamic interaction of local erosion rock uplift thermal weakening of the lithosphere and deformation 1 whereas along the rest of the himalayan front high relief and high rock uplift rates are essentially continuous the high relief and rapid exhumation in the syntaxis is restricted to a bull s eye pattern exactly where the largest river in the himalaya the yarlung tsangpo brahmaputra has the most energy per unit area available to erode its channel and transport sediment 2 the location of rapid incision on the yarlung tsangpo brahmaputra has been pinned for at least 1 m y and without compensatory uplift of the namche barwa gyala peri massif during this time the river would have eroded headward rapidly incising deeply into tibet

late cenozoic right lateral strike slip faulting in southern tibet field observations collected during the sino french himalaya tibet cooperation project 1980 1982 show that right lateral faulting between southern and northern tibet roughly along the chord joining the eastern and western syntaxes of the himalayan arc is a major component of the active tectonics north of the himalayas just north of the well developed rifts of southern tibet we studied three right lateral 100 200 km long strike slip faults forming an en echelon array along that chord evidence for earthquake surface breaks was found on each of these faults for the m 8 beng co or damxung strike slip earthquake of november 18 1951 rupture parameters could be constrained to be 8 2 m and l 90 km offset glacial and postglacial morphological markers 105 years and 104 years b p imply displacement rates of the order of 1 2 cm yr on the three faults the en echelon fault zone appears to extend westward 2000 km across the plateau to the karakorum fault and is thus referred to as the karakorum jiali fault zone kjfz fast rates of slip on it and on faults along the northern rim of tibet appear to contrast with the slower rates of deformations in the interior of the plateau our estimates of slip rates on the strike slip and normal faults of southeastern tibet suggest that eastward extrusion of north tibet between the right lateral kjfz and the left lateral altyn tagh and kun lun faults absorbs at least 30 of the present convergence between india and asia we propose an instantaneous velocity model of the active tectonics of asia compatible with such faulting rates and geometries evidence for tertiary right lateral strike slip movements in southern tibet and around the eastern syntaxis of the himalayas is also found in the structural record offsets of various large scale geological features imply that these movements have been large

biogenic fabrics in seep carbonates from an active gas vent site in green canyon block 238 gulf of mexico abstract carbonate crusts collected from an active methane seep site in the offshore louisiana of gulf of mexico have c pdb 13 49 16 to 52 29 and a group of unsaturated 2 6 10 15 19 pentamethylicosane pmi compounds produced by methane oxidizing archaea moa with c pdb 13 of pmi compounds from 107 2 to 115 5 indicating that the crusts formed as the result of bacterially catalyzed methane oxidation and sulfate reduction the fabric of the two flat sides of the crust is distinctly different the top side is composed entirely of microcrystalline calcite while the bottom is composed entirely of wormy carbonate cement that could be a random low fidelity replacement of bacteria in the interior of the 1 cm thick crust microcrystalline calcite is coated by wormy carbonate cement and dispersed pyrite framboids appear to be collaborating colonies of moa and sulfate reducing bacteria srb we propose that the wormy carbonate texture particularly with microcrystalline calcite and pyrite framboids present may be a useful indicator of biologically controlled fabrics produced during methane oxidation and sulfate reduction by moa and srb

evidence for equatorial kelvin modes in nimbus 7 lims abstract eastward propagating disturbances over the equator are diagnosed in two independent nimbus 7 lims limb infrared monitor of the stratosphere data sets they are evident consistently at several pressure levels throughout the stratosphere and account for much of the temperature variance in the tropics the disturbances which can be seen in wavenumbers 1 3 are in phase and symmetric about the equator latitudinally evanescent and have short moderate vertical phase structure 10 40 km which progresses downward wavenumber 1 has spectral components which propagate eastward at periods of 6 7 8 6 days 54 69 m s 1 and 3 5 4 0 days 115 135 m s 1 wavenumber 2 exhibits eastward propagating variance at periods of 6 0 7 5 days 31 39 m s 1 and 3 8 4 3 days 55 62 m s 1 the faster waves appear principally in the upper stratosphere these features are in reasonable agreement with the structure and dispersion characteristics of simple quasi separable kelvin modes with the exception of the slower w

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

conjugate strike slip faulting along the bangong nujiang suture zone accommodates coeval east west extension and north south shortening in the interior of the tibetan plateau this is the published version copyright 2002 american geophysical union all rights reserved

extreme localized exhumation at syntaxes initiated by subduction geometry some of the highest and most localized rates of lithospheric deformation in the world are observed at the transition between adjacent plate boundary subduction segments the initiating perturbation of this deformation has long been attributed to vigorous erosional processes as observed at nanga parbat and namche barwa in the himalaya and at mount st elias in alaska however an erosion dominated mechanism ignores the 3 d geometry of curved subducting plates here we present an alternative explanation for rapid exhumation at these locations based on the 3 d thermomechanical evolution of collisions between plates with nonplanar geometries comparison of model predictions with existing data reproduces the defining characteristics of these mountains and offers an explanation for their spatial correlation with arc termini these results demonstrate a bottom up tectonic rather than top down erosional initiation of feedbacks between erosion and tectonic deformation hence the importance of 3 d subduction geometry

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

current slip rates on conjugate strike slip faults in central tibet using synthetic aperture radar interferometry this is the published version copyright 2006 american geophysical union all rights reserved

tibetan plateau river incision inhibited by glacial stabilization of the tsangpo gorge much attention has focused on how and when the tibetan plateau formed but far less research has been done on the controls on river incision into the plateau itself oliver korup and david montgomery address this issue which also relates to the question of why the tibetan plateau is still there at all despite hosting one of the deepest gorges on earth the plateau edge is extremely well defined and according to widely accepted stream power theory should be heavily dissected by one of asia s most powerful rivers the yarlung tsangp or yarlung zangbo korup and montgomery propose that the southeastern edge of the plateau was preserved in part by the presence of glaciers that were large enough during the holocene to stall aggressive river downcutting along the plateau margin a considerable amount of research has focused on how and when the tibetan plateau formed in the wake of tectonic convergence between india and asia1 although far less enquiry has addressed the controls on river incision into the plateau itself2 widely accepted theory3 predicts that steep fluvial knick points river reaches with very steep gradients in the eastern himalayan syntaxis at the southeastern plateau margin should erode rapidly4 driving a wave of incision back into the plateau preservation of the plateau edge thus presents something of a conundrum that may be resolved by invoking either differential rock uplift matching erosional decay5 6 7 or other mechanisms for retarding bedrock river incision8 9 in this region where high stream power excludes the potential for aridity as a simple limit to dissection of the plateau10 here we report morphologic evidence showing that quaternary depression of the regional equilibrium line altitude where long term glacier mass gain equals mass loss was sufficient to repeatedly form moraine dams on major rivers such damming substantially impeded river incision into the southeastern edge of the tibetan plateau through the coupled effects of upstream impoundment and interglacial aggradation such glacial stabilization of the resulting highly focused river incision centred on the tsangpo gorge could further contribute to initiating and accentuating a locus of rapid exhumation known as tectonic anaeurysm6

the october 6 2008 mw 6 3 magnitude damxung earthquake yadong gulu rift tibet and implications for present day crustal deformation within tibet abstract a mw 6 3 magnitude earthquake occurred on october 6 2008 in southern damxung county within the n s trending yangyi graben which forms the northern section of the yadong gulu rift of south central tibet the earthquake had a maximum intensity of ix at the village of yangyi also yangying 29 43 3 n 90 23 6 e and resulted in 10 deaths and 60 injured in this sparsely populated region field observations and focal mechanism solutions show normal fault movement occurred along the nne trending western boundary fault of the yangyi graben in agreement with the felt epicenter pattern of the isoseismal contours and distribution of aftershocks the earthquake and its tectonic relations were studied in detail to provide data on the seismic hazard to the nearby city of lhasa the damxung earthquake is one of the prominent events along normal and strike slip faults that occurred widely about tibet before and after the 2008 mw 7 9 magnitude wenchuan earthquake analysis of these recent m 5 0 earthquake sequences demonstrate a kinematic relation between the normal strike slip and reverse causative fault movements across the region these earthquakes are found to be linked and the result of eastward extrusion of two large structural blocks of central tibet the reverse and oblique slip surface faulting along the longmenshan thrust belt at the eastern margin of the tibetan plateau causing the wenchuan earthquake was the result of eastward directed compression and crustal shortening due to the extrusion prior to it east west extensional deformation indicated by normal and strike slip faulting events across central tibet had led to a build up of the compression to the east the subsequent renewal of extensional deformational events in central tibet appears related to some drag effect due to the crustal shortening of the wenchuan event unraveling the kinematical relation between these earthquake swarms is a very helpful approach for understanding the migration of strong earthquakes across tibet

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

a deforming block model for the present day tectonics of tibet 1 we use gps data from 45 sites across the tibetan plateau surveyed between 1991 and 2001 to study the distribution of strain in that part of the india eurasia collision zone the plateau is cut by a few major rapidly slipping strike slip fault zones with broadly distributed strain between those zones the gps velocities can be fit well by a simple deforming block model that combines uniform strain with the motion of blocks separated by the major known fault zones within the plateau the boundaries of the four blocks in this model correspond to the major rapidly slipping faults a rigid block model with a smaller number of blocks fits the data poorly and can be rejected we estimate that 5 9 0 7 mm yr of extension in the n69 w direction occurs on the yadong gulu rift south of the plateau localized extension may extend as far north as the nyainqentanglha range we find 7 4 0 7 mm yr of right lateral slip on the karakorum jiali fault zone significantly slower than that previously estimated from offset geologic features our deforming block model and a two dimensional single fault screw dislocation model give lower and upper bounds of 4 4 1 1 and 10 3 0 4 mm yr on the slip rate on the kunlun fault respectively comparable in its highest to the long term slip rate observed geologically the distributed deformation is surprisingly uniform over the tibetan plateau qaidam basin and qilian shan and approximates a combination of pure shear and uniaxial contraction with the same axes of maximum contraction n32 e this strain field is a combination of shortening and extension that produces little net dilatation 1 area loss per million years at present the broadly distributed strain most likely represents slip on many faults each with a relatively low slip rate distributed conjugate strike slip faulting is the most plausible mechanism to produce the observed strains as supported by the record of medium to large earthquakes within the plateau the distributed deformation is just as important in the accommodation of the total india eurasia convergence as is slip on the major faults the eastward motion of central tibet is as large as 50 of the convergence rate between india and eurasia however this eastward motion is not motion of a relatively undeforming block bounded by rapidly moving strike slip faults as suggested by past extrusion models instead much of this eastward extrusion is driven by the internal extension of the plateau our inference is in agreement with the model of f shen et al 2001 that suggested east west extension north south contraction and eastward plateau growth dominate the present tectonics of the tibetan plateau

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

radiosonde observations of equatorial atmosphere dynamics over indonesia 1 equatorial waves and diurnal tides this paper describes the characteristics of the mean winds equatorial waves with periods ranging from 4 to 20 days and diurnal tides determined by analyzing the profiles of wind velocity temperature and humidity obtained every 5 7 hours in the height range up to about 35 km with a height resolution of 150 m during an observation campaign conducted february 27 to march 22 1990 in east java indonesia the structures of the mean winds in the troposphere and lower stratosphere seemed to be affected by the australian monsoon and the quasi biennial oscillation respectively frequency spectra indicated that the equatorial waves as well as the diurnal tides were dominant below about 25 km while gravity waves with periods shorter than 4 days became more significant above 25 km a 7 day oscillation showing an antiphase relation between the eastward and northward components and exhibiting large amplitudes was observed in the lower troposphere the time height variations of the activity of this 7 day oscillation were clearly correlated with a region of high relative humidity perturbations in the zonal wind and temperature with wave periods varying from 15 to 17 days were also enhanced in the troposphere while kelvin waves with periods of about 7 and 20 days were detected in the lower stratosphere and activity near the tropopause was conspicuously enhanced we found that the 20 day kelvin wave greatly modified the structure of the tropopause such as the minimum temperature the tropopause height and the values of the brunt vaisala frequency squared n2 which further suggests the effects of kelvin waves on the transportation of tropospheric water vapor into the stratosphere and on the downward mixing of stratospheric minor constituents into the troposphere the observed profiles of the diurnal oscillation were compared with those of a numerical model assuming only migrating tides which reasonably agreed above about 25 km below 25 km however the observed amplitudes were 1 1 5 m s exceeding those of the model about 10 times moreover the phase profiles involved fluctuations with small vertical scales suggesting interference by many nonmigrating tides with short vertical wavelengths

displacement and geometrical characteristics of earthquake surface ruptures issues and implications for seismic hazard analysis and the process of earthquake rupture there now exist about three dozen historical earthquakes for which in vestigators have constructed maps of earthquake rupture traces accompanied by de scriptions of the coseismic slip observed along the fault strike the maps and slip distributions are compiled here to place observational bounds on aspects of seismic hazard analysis and fault mechanics analysis leads to an initial statistical basis to predict the end points of rupture and the amount of surface slip expected at sites along the strike during earthquakes on mapped faults the observations also give support to the ideas that there exists a process zone or volume of about 3 4 km in dimension at the fronts of large laterally propagating earthquake ruptures within which stress changes may be sufficient to trigger slip on adjacent faults and that the ultimate length of earthquake ruptures is controlled primarily by the geometrical complexity of fault traces and variations in accumulated stress levels along faults that arise due to the location of past earthquakes to this may be added the observation that the form of earthquake surface slip distributions is better described by asymmetric rather than symmetric curve forms and that earthquake epicenters do not appear to correlate in any systematic manner to regions of maximum surface slip observed along strike online material maps of surface ruptures digitized values and curve fits to surface slip distributions and notes and references for tables 1 and 2

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