multi scale characterisation of coastal sand aquifer media for contaminant transport using x ray computed tomography to be able to predict contaminant transport in groundwater an accurate conceptual and physical understanding of aquifer properties at multiple scales is required in this study physical and hydraulic properties of a coastal sand aquifer were derived using micro and macro x ray computed tomography xct techniques qualitative and quantitative data improved conceptualisation of the aquifer structure at micro and macro scale at the macro scale 50 mm diameter by 1 500 mm long core xct images of undisturbed drill core identified coarse grained laminae not obvious to the naked eye of increased porosity and permeability variations in mineral assemblage and particulate organic matter distribution within the core micro xct analysis 16 mm diameter cores of the three main aquifer layers provided quantitative micro scale data on permeability porosity grain pore and throat size distribution statistics and grain sphericity ratios of mean pore to grain diameter were 0 65 0 75 and ratios of mean throat to mean grain diameter were 0 2 multiple permeability and porosity values were derived from micro domains 4 35 mm3 within each micro xct core permeability values varied between and within micro xct core samples reflecting the heterogeneity at the millimetre core scale in these sediments sphericity values were similar for all three layers average 0 4 which reflected sem observations of the semi spherical nature of the dominant quartz and feldspar grains the results of this study indicate that models based on the assumptions of homogeneity in depositional structure below centimetre scale may not suitably address factors affecting flow and transport of contaminants

geometry and kinematics of recent deformation in the mondy tunka area south westernmost baikal rift zone mongolia siberia we used satellite imagery and field data to investigate the south westernmost baikal rift zone we focus our study in the mondy and ikhe ukhgun valleys site of an mw 6 9 seismic event in 1950 surface deformations are observed along the e w trending mondy strike slip fault and along the ikhe ukhgun thrust the mondy fault system is 80 km long and is composed of four segments 10 15 km long these segments are characterized by subvertical planes with left lateral movements the ikhe ukhgun thrust is 20 km long dips 40 to the south and shows reverse movement with a left lateral component these observations are consistent with the present day regional nne ssw compression and with the focal mechanism of the 1950 mondy earthquake that was recently re evaluated these features like those observed in the tunka basin demonstrate a recent change of regional strain regime from transtension to transpression that we place before the late pleistocene

resolution analysis of tomographic slug test head data two dimensional radial case hydraulic tomography inverse problems which are solved to estimate aquifer hydraulic properties between wells are known to be ill conditioned and a priori information is often added to regularize numerical inversion of head data because both head data and a priori information have effects on the inversed solution assessing the meaningful information contained in head data alone is required to ensure comprehensive interpretation of inverse solutions whether they are regularized or not this study thus aims to assess the amount of information contained in tomographic slug tests head data to resolve heterogeneity in kh kv kh and ss therefore a resolution analysis based on truncated singular value decomposition of the sensitivity matrix with a noise level representative of field measurements is applied using synthetic data reflecting a known littoral aquifer as an approximation of the hydraulic behavior of a real aquifer system synthetic tomographic experiments and associated sensitivity matrices are generated using a radial flow model accounting for wellbore storage to simulate slug tests in a plane encompassing a stressed well and an observation well although fine scale resolution of heterogeneities is limited by the diffusive nature of the groundwater flow equations inversion of tomographic slug tests head data holds the potential to uniquely resolve coarse scale heterogeneity in kh kv kh and ss as inscribed in the resolution matrix this implies that tomographic head data can provide key information on aquifer heterogeneity and anisotropy but that fine scale information must be supplied by a priori information to obtain finer details

three dimensional hydrostratigraphic models from ground penetrating radar and direct push data abstract three dimensional models of hydraulic conductivity and porosity are essential to understand and simulate groundwater flow in heterogeneous geological environments however considering the inherent limitations of traditional hydrogeological field methods in terms of resolution alternative field approaches are needed to establish such 3 d models with sufficient accuracy in this study we developed a workflow combining 3 d structural information extracted from ground penetrating radar gpr images with 1 d in situ physical property estimates from direct push dp logging to construct a 3 d hydrostratigraphic model to illustrate this workflow we collected an 70 m 90 m 100 mhz 3 d gpr data set over a shallow sedimentary aquifer system resolving six different gpr facies down to 15 m depth dp logs of the relative dielectric permittivity the relative hydraulic conductivity the cone resistance the sleeve friction and the pore pressure provided crucial data 1 to establish a gpr velocity model for 3 d depth migration and to check the time to depth conversion of the gpr data and 2 to construct a 3 d hydrostratigraphic model this model was built by assigning porosity values which were computed from the dp relative dielectric permittivity logs and dp relative hydraulic conductivity estimates to the identified gpr facies we conclude that the integration of 3 d gpr structural images and 1 d dp logs of target physical parameters provides an efficient way for detailed 3 d subsurface characterization as needed for example for groundwater flow simulations

soft sediment deformation structures induced by strong earthquakes in southern siberia and their paleoseismic significance abstract liquefaction induced soft sediment deformation structures ssds formed by earthquakes in southern siberia that were historically mentioned or monitored by instruments are described and analyzed clastic dikes are the most common among all ssds in the epicentral areas of the investigated seismic events they are also the most reliable paleoseismic indicators in regions where cryogenic processes are intense we suggest seven criteria that may be useful to distinguish the seismogenic clastic dikes from non seismogenic ssds in a single outcrop 1 pushed up sedimentary blocks within the dike body 2 regular distorted contacts of a dike with host sediments reflecting cyclic loading during propagation of seismic waves 3 turned up layers of host deposits on contacts with a dike 4 displacement along dike contacts usually in the form of a normal fault caused by subsidence that compensates for the removed sediment 5 a dike structure similar to a diapir 6 filling of a clasic dike with coarser materials than the host sediments and 7 a sediment layer extruded on the surface or between strata similar in composition to the dike in the extruded sandy gravel pebble layer rock fragments show normal grading from large to small clasts in addition to these indicators fractures may indirectly indicate the seismogenic genesis of liquefaction induced ssds due to the close spatial relationship of dikes with the fault structures of the investigated areas they can be used to identify seismogenic fault and the characteristics of dikes lateral gradual changes in the frequency size and type of the deformations can help to determine the epicenter magnitude and the local intensity of the associated earthquakes

cryoturbation versus tectonic deformation along the southern edge of the tunka basin baikal rift system siberia new insights from an integrated morphotectonic and stratigraphic study the tunka basin is a broad emerging basin situated between the baikal lake to the east and the the hovsgol lake to the west the basin is bounded to the north and to the south by the tunka and the khamar daban mountain ranges respectively the tunka normal fault located at the southern foothills of the tunka mountain range is the main structure that controlled the development of the tunka basin during the neogene paleoearthquake surface ruptures attest of its present activity and show that its western and eastern terminations are undergoing a tectonic inversion characterized by left lateral reverse deformations the southern edge of the tunka basin is classically interpreted as being tectonically controlled in this paper we present the results of a geomorphological and stratigraphic analysis within its southwestern and southeastern parts suggesting that there is no active fault affecting the foothills of the khamar daban mountain range the different features observed in the quaternary deposits are interpreted to be the result of periglacial processes induced by alternating episodes of permafrost aggradation and degradation during the holocene our study concludes that the khamar daban range and the tunka basin are uplifting together and that the tunka and mondy faults are the two main triggers of regional earthquakes

spatial characterization of the hydraulic conductivity using direct push injection logging 1 detailed information on the spatial structure of hydraulic conductivity k is important for understanding and predicting groundwater flow and transport direct push injection logging dpil is a promising technology for rapid measurement of k in unconsolidated formations this technology was used to gain information on the highly heterogeneous aquifer at the lauswiesen test site in germany using a large body of dpil and direct push slug testing measurements we characterize the structure of k on scales not previously possible two new applications of dpil are put forward 1 use of raw dpil measurements of relative conductivity kr to characterize the spatial distribution of k and 2 transformation of kr measurements to k values based on their statistical moments the dpil results are compatible to those obtained using more conventional methodologies the main achievement of the methodology is the possibility to delineate deterministic aquifer subunits as well as the identification of the statistical parameters of the log conductivity for each subunit in particular the horizontal integral scale i a parameter affecting solute transport is difficult and costly to identify using other approaches nevertheless further studies are needed to clarify questions on low kr measurements and the nature of the relationship between kr and k

measurement of field saturated hydraulic conductivity on fractured rock outcrops near altamura southern italy with an adjustable large ring infiltrometer up to now field studies set up to measure field saturated hydraulic conductivity to evaluate contamination risks have employed small cylinders that may not be representative of the scale of measurements in heterogeneous media in this study a large adjustable ring infiltrometer was designed to be installed on site directly on rock to measure its field saturated hydraulic conductivity the proposed device is inexpensive and simple to implement yet also very versatile due to its large adjustable diameter that can be fixed on site it thus allows an improved representation of the natural system s heterogeneity while also taking into consideration irregularities in the soil rock surface the new apparatus was tested on an outcrop of karstic fractured limestone overlying the deep murge aquifer in the south of italy which has recently been affected by untreated sludge disposal derived from municipal and industrial wastewater treatment plants the quasi steady vertical flow into the unsaturated fractures was investigated by measuring water levels during infiltrometer tests simultaneously subsurface electrical resistivity measurements were used to visualize the infiltration of water in the subsoil due to unsaturated water flow in the fractures the proposed experimental apparatus works well on rock outcrops and allows the repetition of infiltration tests at many locations in order to reduce model uncertainties in heterogeneous media

hydrogeologic facies models to delineate large scale spatial trends in glacial and glaciofluvial sediments recent interest in contaminant transport in ground water has led hydrogeologists to the conclusion that predicting the movement of solutes requires information on the distribution of spatial trends and heterogeneities in porous media description of spatial trends has long been of interest to sedimentologists who have produced a large body of geologic information on the subject in this paper facies models are used to construct conceptual models of hydrogeologic facies for glacialmeltwater stream sediment and till these hydrogeologic facies models which delineate large scale trends in heterogeneity are appropriate for use in designing hydrogeologic field tests and for estimating input to regional ground water flow and transport models this paper treats each facies as a homogeneous anisotropic hydrogeologic unit the models presented herein conceptualize the hydrogeologic relationships among facies and illustrate one method of converting the apparent chaos in nature into an orderly system that can be tested scientifically and modeled mathematically the principles used to create conceptual models of hydrogeologic facies for the types of sediment considered in this paper can be extended to other sedimentary environments it should be recognized however that such models do not address the small scale heterogeneity present within individual facies additional basic research is required to measure hydraulic conductivity variation within representative hydrogeologic facies and to develop statistical descriptions to represent the variations such detailed descriptions of hydraulic conductivity may be necessary to describe ground water flow at a local scale for analysis of contaminant transport

review and comments on late neogene climatic fluctuations and the intermittence of the bering land bridge abstract late miocene to pliocene cooling warming events and the intermittence of the bering land bridge are reviewed based on previous publications the first connection between the pacific and arctic oceans in the miocene and the timing of the establishment of the sub boreal oyashio current in about 1 ma in the northern pacific are also discussed

evaluation of environmental seismic intensities of all known historical and recent earthquakes felt in zakynthos island greece using the environmental seismic intensity esi 2007 scale abstract the complete and detailed knowledge of the historical earthquakes the past earthquake environmental effects eee and the respective seismic intensities has become significant in recent years due to the fact that among others it serves as a valuable tool for revealing and highlighting sites of significant earthquake related hazards many efforts have been made to record the eee of individual recent earthquakes and evaluate their seismic intensity based on the environmental seismic intensity 2007 scale esi 2007 in greece and around the world but fewer studies have focused on the complete seismic history including historical and recent earthquakes of an area and the respective intensities based on the induced eee the central ionian islands western greece and especially zakynthos island are considered appropriate for the development of this approach the complete history of earthquakes with destructive impact on zakynthos from 1513 to present is presented emphasis is given on eee while the respective esi 2007 intensities are assigned based on the eee s distribution on the affected fault blocks it is concluded that eastern zakynthos has been affected more often and severely by earthquakes this selective distribution is attributed to the neotectonic setting of zakynthos the recording of the eee over the past five centuries and the study of possible correlation with the seismotectonic structure of the affected area could be used as a basic guide for the reduction of the future seismic risk and the risk from eee through effective land use planning and preparedness in earthquake prone areas

colloid deposition on non ideal porous media the influences of collector shape and roughness on the single collector efficiency 1 the transport of groundwater colloids e g bacteria viruses clay particles is governed in part by the rate at which the colloids strike and adhere to aquifer mineral grains we report results of coupled flow and transport simulations that reveal how changes in mineral grain shape and surface roughness influence the single collector contact efficiency t a parameter of colloid filtration theory that quantifies the frequency of colloid collisions with the surface of a mineral grain collector our analyses indicate that the sensitivity of t to variations in collector shape and roughness depends on colloid size and suggests that quantitative descriptions of colloid transport through real aquifers will in some cases require nontraditional approaches that are not limited by the simplifying assumptions of smooth spherical collectors

heterogeneity patterns of quaternary glaciofluvial gravel bodies sw germany application to hydrogeology abstract the architecture of sedimentary bodies determines the heterogeneity of many aquifers thus for environmental risk assessment and quantification of clean up efficiencies determination of the spatial distribution of hydraulic properties is required in this study outcrop analogues of glaciofluvial gravel bed deposits are used for a process based analysis of sedimentary heterogeneities which in turn are transformed into hydraulic parameters three scales of heterogeneities are distinguished a the lithofacies scale is formed by unique transport and depositional processes that form the fundamental building blocks hydrofacies types b the depositional element scale shows distinct geometrical characteristics internal structure and bounding surfaces and determines the local distribution of lithofacies and hence the correlation structure of permeabilities c the architectural scale of gravel bodies is formed by the stacking of depositional elements which is controlled by the dynamics of aggrading paleofluvial systems comparison of numerous gravel pits in sw germany revealed three major architectural patterns of glaciofluvial gravel bodies that can be distinguished statistically by the preservation of depositional elements as well as the frequency of lithofacies types the facies analysis results in three conceptual facies models of proglacial river systems which are regionally classified as main intermediate and minor discharge types based on calculated and laboratory measured hydraulic properties of the various lithofacies types detailed outcrop wall maps were digitized into polygons of defined hydrofacies types by using the gis system arc info the two dimensional fields of hydraulic properties were then transferred into a numerical model of groundwater flow modeling results clearly illustrate that the three heterogeneity patterns of gravel bodies also have distinguishable hydraulic response characteristics

3 d sedimentary architecture of a quaternary gravel delta sw germany implications for hydrostratigraphy abstract this paper investigates a quaternary gilbert type gravel delta that was formed in an ice marginal environment at the end of the last glacial period outcrop sediment core and ground penetrating radar gpr studies reveal the sedimentary facies and depositional architecture of the delta that comprises three major units 1 a 2 5 m thick gravelly topset with an erosional base formed by accretion of bedload sheets in a braided river 2 an up to 40 m thick steeply inclined 13 35 foreset dominated by gravelly lithofacies being the product of cohesionless debris flows and debris falls as well as gravity slides while sandy lithofacies was deposited by traction currents and 3 a 10 20 m thick sandy bottomset comprising low density turbidites syn to postdepositional deformation of parts of the bottomset deposits largely resulted from rapid deposition of overlying gravels and differential loading of the prograding foreset beds the development of the delta was most likely controlled by a high sediment supply and lake level fluctuations the overall coarsening upward succession reflects delta progradation and aggradation into a glaciolacustrine environment outcrop sedimentology served as a direct analogue in order to characterise the three dimensional sedimentary and hydraulic architecture of the nearby gravel delta aquifer applying a multidisciplinary approach sedimentological geophysical and hydrogeological data were integrated within the 3 d modelling package gocad earth decision sciences to develop high resolution 3 d aquifer models

the use of distinct disciplines to investigate past earthquakes abstract the investigation of past earthquakes can be approached in many different ways with a large variety of methods and techniques this is mainly due to the complexity of this natural phenomenon in both its genetic aspects and consequential ones in the present note we briefly analyse the peculiarities of instrumental seismology historical seismology archaeoseismology and earthquake geology but especially we emphasise the major differences among these four distinct approaches in order to better define and clearly separate these disciplines in terms of appropriate tools to be applied and possible outcomes to be expected an alternative point of view is proposed based on the source of information and not on a chronological distribution as commonly accepted in the literature although multidisciplinarity is a common approach for investigating past earthquakes each one of the discussed disciplines has its own peculiarities advantages and limitations and researchers should be aware of this

process dependent residual trapping of co2 in sandstone this paper demonstrates that the nature and extent of residual co2 trapping depend on the process by which the co2 phase is introduced into the rock we compare residual trapping of co2 in berea sandstone by imbibing water into a core containing either exsolved co2 or co2 introduced by drainage x ray computed tomography measurements are used to map the spatial distribution of co2 preimbibition and postimbibition unlike during drainage where the co2 distribution is strongly influenced by the heterogeneity of the rock the distribution of exsolved co2 is comparatively uniform postimbibition the co2 distribution retained the essential features for both the exsolved and drainage cases but twice as much residual trapping is observed for exsolved co2 even with similar preimbibition gas saturations residually trapped exsolved gas also disproportionately reduced water relative permeability development of process dependent parameterization will help better manage subsurface flow processes and unlock benefits from gas exsolution

ground effects of the 18 october 1992 murindo earthquake nw colombia using the environmental seismic intensity scale esi 2007 for the assessment of intensity

characterizing the present day activity of the tunka and sayan faults within their relay zone western baikal rift system russia the sayan and tunka faults are located at the boundary between the northernmost mountain belt of central asia the sayan baikal ranges and the siberian platform these prominent crustal structures were involved in the opening of the southern baikal rift system since the beginning of the cenozoic and define large scale sharp morphotectonic features despite low instrumental seismic activity late pleistocene holocene morphotectonic features along the two faults indicate that the faults are active and have the capacity to produce strong earthquakes a careful mapping of the most recent trace of activity within the southeastern parts of the two faults where they merge within a relay zone demonstrates that they correspond now to left lateral reverse faults suggesting a recent inversion of their vertical component we also show that the two faults are now structurally connected via a young surface rupture and that no obvious post last glacial maximum ruptures are observed along the central part of the sayan fault beyond its junction zone with the tunka fault this suggests that the left lateral strike slip deformation is transferred from the eastern sayan fault to the tunka fault a detailed morphotectonic study along the southeastern sayan fault allows estimating a left lateral slip rate between 1 3 min and 3 9 mm year max finally a critical review of russian paleoseismic data combined with our paleoseismological investigations allows us to propose that the mean recurrence time along the two faults is on the order of 4 kyr and that they may have either ruptured together or during seismic clusters

sedimentology and hydrogeology of two braided stream deposits abstract two approaches were used to quantify the spatial distribution of hydrofacies in braided stream deposits one approach involved mapping a 50 by 60 by 3 3 m section of a proximal braided stream deposit in a second study we generated a 400 by 400 by 2 6 m section of a medial braided stream deposit using a computer model in both cases we produced three dimensional images showing connected hydrofacies with high permeabilities that form preferential flow paths this information was input to a groundwater flow model and flow paths were analyzed by following the transport of imaginary particles in both systems particles that were uniformly distributed at the up gradient end of the model clustered along preferential flow paths during transport showing that connection among high permeability facies is a critical factor in hydrogeological investigations involving assessment of contaminant movement and remediation

rapid bacteriophage ms2 transport in an oxic sandy aquifer in cold climate field experiments and modeling virus removal during rapid transport in an unconfined low temperature 6 c sand and gravel aquifer was investigated at a riverbank field site 25 km south of trondheim in central norway the data from bacteriophage ms2 inactivation and transport experiments were applied in a two site kinetic transport model using hydrus 1d to evaluate the mechanisms of virus removal and whether these mechanisms were sufficient to protect the groundwater supplies the results demonstrated that inactivation was negligible to the overall removal and that irreversible ms2 attachment to aquifer grains coated with iron precipitates played a dominant role in the removal of ms2 4 1 log units of ms2 were removed by attachment during 38 m travel distance and less than 2 days residence time although the total removal was high pathways capable of allowing virus migration at rapid velocities were present in the aquifer the risk of rapid transport of viable viruses should be recognized particularly for water supplies without permanent disinfection

bentheimer sandstone revisited for experimental purposes abstract bentheimer sandstone outcrop samples are ideal for laboratory studies due to their lateral continuity and block scale homogeneous nature over the years they have been used to investigate reservoir topics ranging from passive and active properties of oil gas water rock interaction and processes to flow and transport this work shows an evaluation of bentheimer sandstone properties and their characteristics to advance understanding on the mineral accessory and the physical and electrical transport properties on the basis of the nature of depositional environments and diagenesis we measure and characterize spatial attributes of the matrix mainly by qualitative analysis laboratory and stereological measurements and statistical 2d 3d reconstructions the main contribution of this paper is the impact of mineral composition on the petrophysical quality and block scale homogeneity of the reservoir with 3d techniques reconstructions of the new rock grain framework pore structures have been created based on measurements a review of literature data and interpretation of variation between the outcrops and flow relevant parameters we conclude that bentheimer sandstone is a rock that shows constant mineralogy and is largely free of paramagnetic impurities in accordance with the results of 3d reconstructions techniques and in line with the depositional settings they show a well sorted grain framework and a pore network that can be used to calculate the permeability and resistivity without conducting any direct laboratory measurements of either parameter it presents a porosity with a range of 0 21 0 27 and permeabilities varying between 0 52 and 3 02 darcy based on our work and literature it is found that high permeability together with similar distribution of pore throats and bodies make the sandstone an attractive and easy obtainable candidate for comparative experimental studies moreover we state by comparing various techniques that the efficiency and resolution accuracy of the applied method must be taken into consideration when planning the measurements

advances and limitations of the environmental seismic intensity scale esi 2007 regarding near field and far field effects from recent earthquakes in greece implications for the seismic hazard assessment the new environmental seismic intensity scale esi 2007 introduced by inqua incorporates the advances and achievements of palaeoseismology and earthquake geology and evaluates earthquake size and epicentre solely from the earthquake environmental effects eee this scale is tested and compared with traditional existing scales for the 1981 alkyonides earthquake sequence in the corinth gulf ms 6 7 ms 6 4 ms 6 3 the 1993 pyrgos event ms 5 5 and the 2006 kythira event mw 6 7 these earthquakes were of different magni tudes focal mechanisms and focal depths and produced well documented environmental effects the esi 2007 intensity values and the isoseismal pattern for the 1993 pyrgos and the 2006 kythira events are similar to those resulting from the traditional scales demonstrating that for moderate intensity levels vii and viii the esi 2007 and the traditional scales comply well in contrast the 1981 alkyonides earthquake sequence shows that there is an inconsistency between the esi 2007 and the traditional scales both in the epicentral area where higher esi 2007 intensity values have been assigned and for the far field effects the esi 2007 scale offers higher objectivity in the process of assessing macroseismic intensities particularly in the epicentral area than traditional intensity scales that are influenced by human parameters the esi 2007 scale follows the same criteria environmental effects for all events and can compare not only events from different settings but also contemporary and future earthquakes with histori cal events a reappraisal of historical earthquakes so as to constrain the esi 2007 scale may prove beneficial for seismic hazard assessment by reducing the uncertainty implied in the attenuation laws which constitute one of the most important seismic hazard parameters

screening and ranking of sedimentary basins for sequestration of co2 in geological media in response to climate change sedimentary basins are suitable to different degrees for co2 geological sequestration as a result of various intrinsic and extrinsic characteristics of which the geothermal regime is one of the most important warm basins are less favorable for co2 sequestration than cold basins because of reduced capacity in terms of co2 mass and because of higher co2 buoyancy which drives the upward co2 migration a set of 15 criteria with several classes each has been developed for the assessment and ranking of sedimentary basins in terms of their suitability for co2 sequestration using a parametric normalization procedure a basin s individual scores are summed to a total score using weights that express the relative importance of different criteria the total score is ranked to determine the most suitable basin or region thereof for the geological sequestration of co2 the method is extremely flexible in that it allows changes in the functions that express the importance of various classes for any given criterion and in the weights that express the relative importance of various criteria examples of application are given for canada s case and for the alberta basin in canada

the 12 may 2008 mw 7 9 wenchuan china earthquake macroseismic intensity assessment using the ems 98 and esi 2007 scales and their correlation with the geological structure the wenchuan earthquake of 12 may 2008 in sichuan province china can be classified as a large scale event based on the tectonic structures that triggered the earthquake and the effects caused on the human structural and natural environment this paper presents the geotectonic and seismotectonic regime of the earthquake affected region on the basis of field data obtained along the seismic fault zone and provides 1 an estimation of the intensity values according to the ems 98 and the esi 2007 scales and the determination of their large scale geographical distribution along the causative tectonic structure 2 an interpretation of the intensity distribution according to the seismotectonic geodynamic and geotechnical framework and 3 a comparison between two different intensity scales the ems 98 which is essentially based on the effects on the built environment and the esi 2007 which is based on earthquake environmental effects the application of both ems 98 and esi 2007 and the comparative review and evaluation of the results indicate that the estimated values of the ems 98 and the esi 2007 were similar this suggests that both scales can be useful and reliable tools for seismic hazard estimation

effects of kinetic mass transfer and transient flow conditions on widening mixing zones in coastal aquifers 1 the width of a mixing zone between freshwater and seawater is important primarily because it directly reflects the extent of mixing and the growth and decay of the mixing zone indicates changes of the flow regime and water exchange between freshwater and coastal seawater wide mixing zones have been found in many coastal aquifers all over the world however the mechanisms responsible for wide mixing zones are not well understood this work examines the hypothesis that kinetic mass transfer coupled with transient conditions which create the movement of the mixing zone may widen mixing zones in coastal aquifers the hypothesis is tested by conducting two dimensional numerical simulations based on a variable density groundwater model for a scaled tank model and a field scale model periodic water levels representing periodic tidal motion and freshwater table fluctuations are imposed at the seaward and landward boundary respectively which cause the movement of the mixing zone both the scaled tank model and the field model show that the combination of the moving mixing zone and kinetic mass transfer may significantly enhance the extent of mixing and create a wider mixing zone than the models without kinetic mass transfer in addition sensitivity analyses indicate that a larger capacity ratio immobile porosity mobile porosity of mass transfer leads to a wider mixing zone and the maximum width of the mixing zone may be reached for a given capacity ratio when the mean retention time scale in the immobile domain the reciprocal of mass transfer rate and the period of water level fluctuations are comparable

depositional and tectonic setting of the miocene wood mountain formation southern saskatchewan coarse gravels of the miocene wood mountain formation that cap the wood mountain upland in southern saskatchewan are an erosional remant of a much more expansive sheet of gravel and sand the formation consists of gravel and sand deposited as a thin sheet on a regional planation surface that extends approximately along strike for at least 160 km this sheet with a maximum thickness of 31 m is the deposit of low sinuosity braided river channels that flowed to the north northeast the wood mountain formation represents an initial episode of erosion followed by low accommodation deposition where the net aggradation rate was likely low the sediments of the wood mountain formation are associated with change in tectonic style in western north america from one of compression to one of extension the gravels were deposited above a regional erosion surface associated with isostatic uplift of the central montana uplift

parameter estimation for a karst aquifer with unknown thickness using the genetic algorithm method the thickness of an aquifer b is a critical hydrogeologic parameter in understanding groundwater system especially in a karst aquifer where the high heterogeneity in this parameter brings more uncertainty to the evaluation of groundwater resources in this study the genetic algorithm ga method was used to estimate b as well as five other parameters including k r horizontal hydraulic conductivity k z vertical hydraulic conductivity s storativity s y specific yield and delayed coefficient of a karst aquifer based on a pumping test the search bounds of the six parameters for the ga method were obtained from numerous hypothetic numerical tests the feasibility of the ga method for parameter estimation was verified by the results obtained from the gradient method in terms of a pumping test conducted in the platte river valley in nebraska then this approach was used to estimate the hydraulic parameters in a karst aquifer with unknown aquifer thickness based on a pumping recovery test conducted in the houzhai karst basin southwestern china the results show that the k r k z and the anisotropy ratio of k r to k z are strongly affected by b the differences between the estimated parameter values at two observation wells indicate the existence of high heterogeneity in the karst aquifer the parameter b has the highest absolute normalized sensitivity among these variables implying that the estimated b may be more reliable as compared to other parameters this study demonstrates that the ga method is an alternative method of parameter estimation with the unknown aquifer thickness

holocene development of parabolic dunes in the central st lawrence lowland quebec abstract stabilized parabolic dunes in the central st lawrence lowland are oriented ne sw in the postulated direction of dune building winds coming from anticyclonic air circulation induced by the retreating laurentide ice sheet about 10 000 yr ago the eolian chronology reconstructed from several sections in mixed dune peatland environments indicates that postglacial plant colonization characterized by a fortuitous assemblage of arctic subarctic and boreal elements preceded dune formation during champlain sea regression around 10 000 yr b p confined peatlands and small forests were buried by eolian sands between 10 000 and 7500 yr b p under dry and temperate conditions this eolian episode lasted about 2500 14 c yr and ended when cyclonic air circulation similar to the present humid climatic regime was established following the breakup and disappearance of the laurentide ice sheet over hudson bay and peripheral areas dune stabilization through paludification of well drained eolian sands about 7500 yr b p suggests a major shift in climate toward wetter conditions that have been characteristic during most of the holocene in eastern north america minor eolian erosion induced by wildfire was recorded during late holocene time about 1250 yr b p anthropogenic perturbation logging and agriculture practice was also responsible for recent very local eolian activity

identifying hydraulically conductive fractures with a slow velocity borehole flowmeter the u s geological survey used a recently developed heat pulse flowmeter to measure very slow borehole axial water velocities in granitic rock at a site near lac du bonnet manitoba canada the flowmeter was used with other geophysical measurements to locate and identify hydraulically conducting fractures contributing to the very slow vertical water flow in the two boreholes selected for study the heat pulse flowmeter has no moving parts and operates on the tag trace principle it is an improved version of the flowmeter developed by the water research centre in england in 1975 the u s geological survey s heat pulse flowmeter has a flow measuring range in water of 0 06 6 m min and can resolve velocity differences as slow as 0 01 m min this is an order of magnitude slower than the stall speed of spinner flowmeters the flowmeter is 1 16 m long and 44 mm in diameter it was calibrated in columns of 76 and 152 mm diameter to correspond to the boreholes studied the heat pulse flowmeter system is evalu

delineating subsurface heterogeneity at a loop of river steinlach using geophysical and hydrogeological methods stratigraphic heterogeneity is a key controlling factor for flow and transport in groundwater systems in this case study we have combined two and three dimensional images of electric resistivity with hydrogeological data to delineate such stratigraphic heterogeneity at a loop of river steinlach close to tubingen germany where we estimated spatially varying aquifer parameters using established evaluation techniques we developed a three layer stratigraphic model consisting of heterogeneous sandy gravel overlain by a fine alluvium including top soil and underlain by sandstone weathered at its top the sandy gravel makes up the aquifer unit while we interpret the sandstone as aquitard we classified the area into two stratigraphic segments based on resistivity data the southern segment consists of a thicker alluvium where the aquifer material contains more clay than in the northern segment two different stratigraphic structures were also delineated at the southern and northern segments respectively these structures are visible in inversion results as low resistivity features trending in the se nw in the southern segment and ne nw in the northern segment both structures may be previous flow paths of river steinlach and the low permeability material overlying them may impair flow exchange in the area we performed slug and pumping tests to estimate the hydraulic conductivity k of the aquifer the k distributions show slight variation with higher values obtained at wells within the northern segment and close to the river bank a qualitative comparison of measured hydraulic conductivities with the resistivity distribution shows good agreement of the spatial patterns the stratigraphic and hydraulic heterogeneities delineated in this work are important for experimental and modeling studies of flow transport and hyporheic exchange at the site

characterization of deltaic sediment bodies based on in situ cpt cptu profiles a case study on the llobregat delta plain barcelona spain abstract this article describes a preliminary study on the llobregat delta spain which includes the construction of a 3d model from cone penetration tests cpt and piezocone tests cptu in order to establish the architectural stacking pattern of deltaic sediment bodies the sediment facies identified from boreholes have been characterized by using their mechanical behaviour and have been used to identify the depositional sequence of the llobregat delta within the general architectural frame flood plain silts and silty sands crevasse sands fluvial channel sands sand ridges delta front silts and clays and prodelta silts and clays have been characterized as a function of cone tip resistance q c and sleeve friction f s from the sediment facies characterization a depositional sequence constituted by three systems tracts is proposed the sequence is divided into a lowstand systems tract lst represented by fluvial gravels a transgressive systems tract tst constituted by a fining upward sequence with a thin sand sheet below silts and clays and the highstand systems tract hst represented by three prograding wedges displaying coarsening upward sequences we emphasize the simplicity speed high spatial resolution and low cost of cpt cptu grids as a new tool enabling us to reconstruct the three dimensional structure of deltaic environments for sedimentological and stratigraphical purposes

pore scale imaging and analysis of phase topologies and displacement mechanisms for co2 brine two phase flow in unconsolidated sand packs co2 storage in saline aquifers is considered a potential solution for co2 mitigation owing to its significant capacity and worldwide distribution capability it is therefore becoming more important to understand the underground co2 brine flow mechanisms co2 migration is primarily controlled by the pore scale subsurface flows in different saline aquifer sites with variable reservoir formation compositions and reservoir conditions variations occur in the state of co2 phase gas versus supercritical brine salinity and rock wettability under different reservoir conditions and may result in different subsurface co2 brine migration phenomena in this study we investigate the drainage and imbibition procedures of co2 and brine by injecting fluids into unconsolidated sand packs under different conditions of co2 phase states brine salinity and wettability of sand packs the pore scale fluid distribution is visualized using micro x ray computed tomography micro ct it is found that the phase states of co2 brine salinity and wettability have low impacts on co2 distribution during drainage however the increase in brine salinity significantly damages the connectedness of the water phase in pore structures and further decreases the co2 brine interfacial areas in addition a pore scale event called the droplet fragmentation of nonwetting phase is found to occur in the imbibition procedure which is considered to be beneficial to the dissolution trapping in co2 geological storages it is experimentally demonstrated that the pore structure of rock cores is a factor that significantly contributes to droplet fragmentation

a reappraisal of the 1950 mw 6 9 mondy earthquake siberia and its relationship to the strain pattern at the south western end of the baikal rift zone the precise nature of the transition between the present day compressional tectonics in central mongolia and extensional deformation in the central baikal rift has still to be determined for that purpose we have built a comprehensive earthquake focal mechanism data base for the mongolia southern siberia area from which we map the variations of the stress field we focus our detailed investigations on the largest seismic event in the transition zone the 1950 mw 6 9 mondy earthquake for which several discordant focal mechanisms have been proposed using a new approach in source inversion we resolve the focal mechanism left lateral strike slip type on a steep south dipping fault and depth 14 3 km of the mondy earthquake with a satisfactory accuracy this seismological information combined with the geological observations allows us to decipher the connections between the 1950 mainshock the local stress tensor and the active faults which strongly suggest a partitioning of the deformation between two faults namely the mondy and ikhe ukghun faults

patterns and dynamics of river aquifer exchange with variably saturated flow using a fully coupled model summary the parallel physically based surface subsurface model parflow was used to investigate the spatial patterns and temporal dynamics of river aquifer exchange in a heterogeneous alluvial river aquifer system with deep water table aquifer heterogeneity at two scales was incorporated into the model the architecture of the alluvial hydrofacies was represented based on conditioned geostatistical indicator simulations subscale variability of hydraulic conductivities k within hydrofacies bodies was created with a parallel gaussian simulation the effects of subscale heterogeneity were investigated in a monte carlo framework dynamics and patterns of river aquifer exchange were simulated for a 30 day flow event simulation results show the rapid formation of saturated connections between the river channel and the deep water table at preferential flow zones that are characterized by high conductivity hydrofacies where the river intersects low conductivity hydrofacies shallow perched saturated zones immediately below the river form but seepage to the deep water table remains unsaturated and seepage rates are low preferential flow zones although only taking up around 50 of the river channel account for more than 98 of total seepage groundwater recharge is most efficiently realized through these zones subscale variability of k sat slightly increased seepage volumes but did not change the general seepage patterns preferential flow zones versus perched zones overall it is concluded that typical alluvial heterogeneity hydrofacies architecture is an important control of river aquifer exchange in rivers overlying deep water tables simulated patterns and dynamics are in line with field observations and results from previous modeling studies using simpler models alluvial heterogeneity results in distinct patterns and dynamics of river aquifer exchange with implications for groundwater recharge and the management of riparian zones e g river channel floodplain connectivity via saturated zones

field characterization and data integration to define the hydraulic heterogeneity of a shallow granular aquifer at a sub watershed scale providing a sound basis for aquifer management or remediation requires that hydrogeological investigations carried out to understand groundwater flow and contaminant transport be based on representative data that capture the heterogeneous spatial distribution of aquifer hydraulic properties this paper describes a general workflow allowing the characterization of the heterogeneity of the hydraulic properties of granular aquifers at an intermediate scale of a few km2 the workflow involves characterization and data integration steps that were applied on a 12 km2 study area encompassing a decommissioned landfill emitting a leachate plume and its main surface water receptors the sediments composing the aquifer were deposited in a littoral sublittoral environment and show evidence of small scale transitional heterogeneities cone penetrometer tests cpt combined with soil moisture and electrical resistivity smr measurements were thus used to identify and characterize spatial heterogeneities in hydraulic properties over the study area site specific statistical relationships were needed to infer hydrofacies units and to estimate hydraulic properties from high resolution cpt smr soundings distributed all over the study area a learning machine approach was used due to the complex statistical relationships between colocated hydraulic and cpt smr data covering the full range of aquifer materials application of this workflow allowed the identification of hydrofacies units and the estimation of horizontal hydraulic conductivity vertical hydraulic conductivity and porosity over the study area the paper describes and discusses data acquisition and integration methodologies that can be adapted to different field situations while making the aquifer characterization process more time efficient and less labor intensive

earthquake intensity assessment based on environmental effects principles and case studies the comparison of intensity assessments based on macroseismic data and earthquake environmental effects eee is presented specific problems faced when assessing intensities using different types of scales are discussed two case studies of recent earthquakes with magni tudes ms 7 4 altai 2003 and neftegorsk 1995 are used to illustrate the applicability of the inqua eee scale the altai earthquake was accompanied by surface faulting of c 70 km length and up to 2 m of horizontal and 70 cm of vertical offset secondary eee were observed over 3000 km 2 the dominant type of surface faulting during the neftegorsk earthquake was strike slip the length of surface faulting was up to 46 km maximum horizontal offset was 8 1 m and average offset coherent with seismic momentwas 3 9 m secondary eee were observed occasionally at considerable distance from the epicentre on wet seashore sands application of the inqua scale shows the epicentral intensity of the altai earthquake to be x degrees most consist ent with all types of data rupture length maximum and average offsets intensity assessment for the neftegorsk earthquake which is within the x xi degree range taking into account environ mental effects in intensity scales is an essential requirement it follows from the complex nature of an earthquake impact which spans a very broad frequency range including static deformations the case studies illustrate that the intensity assessment of an earthquake based only on damage to buildings will be essentially incomplete

numerical analysis of the groundwater regime in the western dead sea escarpment israel west bank water is scarce in the semi arid to arid regions around the dead sea where water supply mostly relies on restricted groundwater resources due to increasing population in this region the regional aquifer system is exposed to additional stress this results in the continuous decrease in water level of the adjacent dead sea the interaction of an increasing demand for water due to population growth and the decrease of groundwater resources will intensify in the near future thus the water supply situation could worsen significantly unless sustainable water resource management is conducted in this study we develop a regional groundwater flow model of the eastern and southern judea group aquifer to investigate the groundwater regime in the western dead sea drainage basin of israel and the west bank an extensive geological database was developed and consequently a high resolution structural model was derived this structural model was the basis for various groundwater flow scenarios the objective was to capture the spatial heterogeneity of the aquifer system and to apply these results to the southern part of the study area which has not been studied in detail until now as a result we analyzed quantitatively the flow regime the groundwater mass balance and the hydraulic characteristics hydraulic conductivity and hydraulic head of the cretaceous aquifer system and calibrated them with pest the calibrated groundwater flow model can be used for integrated groundwater water management purposes in the dead sea area especially within the framework of the sumar project

co2 wettability of seal and reservoir rocks and the implications for carbon geo sequestration we review the literature data published on the topic of co2 wettability of storage and seal rocks we first introduce the concept of wettability and explain why it is important in the context of carbon geo sequestration cgs projects and review how it is measured this is done to raise awareness of this parameter in the cgs community which as we show later on in this text may have a dramatic impact on structural and residual trapping of co2 these two trapping mechanisms would be severely and negatively affected in case of co2 wet storage and or seal rock overall at the current state of the art a substantial amount of work has been completed and we find that sandstone and limestone plus pure minerals such as quartz calcite feldspar and mica are strongly water wet in a co2 water system oil wet limestone oil wet quartz or coal is intermediate wet or co2 wet in a co2 water system the contact angle alone is insufficient for predicting capillary pressures in reservoir or seal rocks the current contact angle data have a large uncertainty solid theoretical understanding on a molecular level of rock co2 brine interactions is currently limited in an ideal scenario all seal and storage rocks in cgs formations are tested for their co2 wettability achieving representative subsurface conditions especially in terms of the rock surface in the laboratory is of key importance but also very challenging

first evidence of percids teleostei perciformes in the miocene of north america miocene sediments of southern saskatchewan have long been known for the mammalian fauna they have produced but little or nothing has been reported of the associated fish material recent examination of this material collected over half a century ago has revealed the presence of a walleye fish walleyes and other members of the family percidae had previously been thought to have arrived in north america as late as the pleistocene and only in the last few years has evidence been found demonstrating their existence in north america in the pliocene the pliocene material from arctic canada indicated that percids may have invaded north america from europe during the late tertiary via the bering isthmus the material presented here shows that in fact percids were already in more southern areas of canada about 10 million years prior to the arctic walleye

ground penetrating radar for high resolution mapping of soil and rock stratigraphy ground penetrating radar is a technique which offers a new way of viewing shallow soil and rock conditions the need to better understanding overburden conditions for activities such as geochemical sampling geotechnical investigations and placer exploration as well as the factors controlling groundwater flow has generated an increasing demand for techniques which can image the subsurface with higher resolution than previously possible the areas of application for ground penetrating radar are diverse the method has been used successfully to map ice thickness water depth in lakes bedrock depth soil stratigraphy and water table depth it is also used to delineate rock fabric detect voids and identify karst features the effective application of the radar for the high resolution definition of soil stratigraphy and fractures in bedrock is highlighted the basic principles and practices involved in acquiring high quality radar data in the field are illustrated by selected case histories one example demonstrates how radar has been used to map the bedrock and delineate soil horizons to a depth of more than 20 m two case histories show how radar has been used to map fractures and changes of rock type to 40 m range from inside a mine another case history demonstrates how radar has also been used to detect and map the extent of groundwater contamination the corroboration of the radar results by borehole investigations demonstrates the power and utility of the high resolution radar method as an aid for interpolation and extrapolation of the information obtained with conventional coring programmes with the advent of new instrumentation and field procedures the routine application of the radar method is becoming economically viable and the method will see expanded use in the future

the need to adapt the exploration model from the oil patch to contaminated site characterization a case from hill afb utah usa for decades the oil industry has employed a working model for hydrocarbon exploration in which large scale geophysical surveys are undertaken prior to a second phase of intensive targeted drilling this latter phase may be conducted in conjunction with further focused geophysical studies the geophysical surveys provide lateral coverage and continuity that are used to drive placement of drilling locations the reason for this approach is simple wells are expensive relative to geophysical surveys also practical limits on lateral coverage preclude optimization of exploration targets based on well information alone

palaeoseismology historical and prehistorical records of earthquake ground effects for seismic hazard assessment given the tremendous toll in human lives and attendant economic losses it is appropriate that scientists are working hard to understand better earthquakes with the aim of forecasting and ultimately predicting them in the last decades increasing attention has been paid to the coseismic effects on the natural environment creating a solid base of empirical data for the estimation of source parameters of strong earthquakes based on geological observations the recently introduced inqua scale environmental seismic intensity esi 2007 scale of macroseismic intensity clearly shows how the systematic study of earthquake surface faulting coseismic liquefaction tsunami deposits and other primary and secondary ground effects can be integrated with traditional seismological and tectonic information to provide a better understanding of the seismicity level of an area and the associated hazards at the moment this is the only scientific means of equating the seismic records to the seismic cycle time spans extending the seismic catalogues even to tens of thousands of years improving future seismic hazard analyses this special publication covers some of the latest multidisciplinary work undertaken to achieve that aim eighteen papers from research groups from all continents address a wide range of topics related both to palaeoseismological studies and assessment of macroseismic intensity based only on the natural phenomena associated with an earthquake

pore scale simulation of carbonate dissolution in micro ct images we present a particle based method to simulate carbonate dissolution at the pore scale directly on the voxels of three dimensional micro ct images the flow field is computed on the images by solving the incompressible navier stokes equations rock fluid interaction is modeled using a three step approach solute advection diffusion and reaction advection is simulated with a semianalytical pore scale streamline tracing algorithm diffusion by random walk is superimposed while the reaction rate is defined by the flux of particles through the pore solid interface we derive a relationship between the local particle flux and the independently measured batch calcite dissolution rate we validate our method against a dynamic imaging experiment where a ketton oolite is imaged during co2 saturated brine injection at reservoir conditions the image calculated increases in porosity and permeability are predicted accurately and the spatial distribution of the dissolution front is correctly replicated the experiments and simulations are performed at a high flow rate in the uniform dissolution regime pe 1 and peda 1 thus extending the reaction throughout the sample transport is advection dominated and dissolution is limited to regions with significant inflow of solute we show that the sample averaged reaction rate is 1 order of magnitude lower than that measured in batch reactors this decrease is the result of restrictions imposed on the flux of solute to the solid surface by the heterogeneous flow field at the millimeter scale

pore scale imaging of geological carbon dioxide storage under in situ conditions 1 while geological carbon dioxide co2 storage could contribute to reducing global emissions it must be designed such that the co2 cannot escape from the porous rock into which it is injected an important mechanism to immobilize the co2 preventing escape is capillary trapping where co2 is stranded as disconnected pore scale droplets ganglia in the rock surrounded by water we used x ray microtomography to image at a resolution of 6 4 m the pore scale arrangement and distribution of trapped co2 clusters in a limestone we applied high pressures and temperatures typical of a storage formation while maintaining chemical equilibrium between the co2 brine and rock substantial amounts of co2 were trapped with an average saturation of 0 18 the cluster sizes obeyed a power law distribution with an exponent of approximately 2 1 consistent with predictions from percolation theory this work confirms that residual trapping could aid storage security in carbonate aquifers

modeling cross hole slug tests in an unconfined aquifer abstract a modified version of a published slug test model for unconfined aquifers is applied to cross hole slug test data collected in field tests conducted at the widen site in switzerland the model accounts for water table effects using the linearized kinematic condition the model also accounts for inertial effects in source and observation wells the primary objective of this work is to demonstrate applicability of this semi analytical model to multi well and multi level pneumatic slug tests the pneumatic perturbation was applied at discrete intervals in a source well and monitored at discrete vertical intervals in observation wells the source and observation well pairs were separated by distances of up to 4 m the analysis yielded vertical profiles of hydraulic conductivity specific storage and specific yield at observation well locations the hydraulic parameter estimates are compared to results from prior pumping and single well slug tests conducted at the site as well as to estimates from particle size analyses of sediment collected from boreholes during well installation the results are in general agreement with results from prior tests and are indicative of a sand and gravel aquifer sensitivity analysis show that model identification of specific yield is strongest at late time however the usefulness of late time data is limited due to the low signal to noise ratios

hydraulic conductivity heterogeneity of a local deltaic aquifer system from the kriged 3d distribution of hydrofacies from borehole logs valcartier canada summary the deltaic aquifer system of the valcartier sector in quebec canada is part of a quaternary valley fill contaminated by dissolved trichloroethene tce the objective of our study is to define the aquifer system heterogeneity that should influence tce transport heterogeneity is defined by the distribution of both hydrofacies and hydraulic conductivity k hydrofacies are defined as lithologic facies with distinctive hydraulic conductivity ranges our approach was developed to take advantage of the abundant stratigraphic and lithologic data provided by borehole logs 7000 m logged from 430 locations four site specific deltaic hydrofacies were defined on the basis of lithologic descriptions supported by data from grain size analyses slug tests and cone penetration tests each hydrofacies includes a group of geologic facies found in borehole log descriptors to which an initial mean horizontal conductivity k h is associated based on slug tests borehole logs were converted to hydrofacies proportions over 5 m intervals to provide 1350 data points the spatial distribution of hydrofacies was interpolated by three successive interconnected 3d kriging steps using the new technique of imbricated kriging global dual kriging is directly carried out on the 3d grid of a numerical model finally the proportions of hydrofacies were used to estimate horizontal k h and vertical k v hydraulic conductivity fields using generalized means for layered media final k h values assigned to the hydrofacies are calibrated by comparison with 2d trends in k h shown by slug tests this approach also provides an estimated vertical k v field with a spatially varying proportion to k h rather than a fixed anisotropy ratio imbricated kriging does not preserve the statistical variability of fine scale hydrofacies distribution representative of geological variability however the approach provides k h and k v estimates over a 3d numerical grid that are coherent with hydrofacies distribution which in this case control k h and k v

historical earthquakes studies in eastern siberia state of the art and plans for future abstract many problems in investigating historical seismicity of east siberia remain unsolved a list of these problems may refer particularly to the quality and reliability of data sources completeness of parametric earthquake catalogues and precision and transparency of estimates for the main parameters of historical earthquakes the main purpose of this paper is to highlight the current status of the studies of historical seismicity in eastern siberia as well as analysis of existing macroseismic and parametric earthquake catalogues we also made an attempt to identify the main shortcomings of existing catalogues and to clarify the reasons for their appearance in the light of the history of seismic observations in eastern siberia contentious issues in the catalogues of earthquakes are considered by the example of three strong historical earthquakes important for assessing seismic hazard in the region in particular it was found that due to technical error the parameters of large m 7 7 earthquakes of 1742 were transferred from the regional catalogue to the worldwide database with incorrect epicenter coordinates the way some stereotypes concerning active tectonics influences on the localization of the epicenter is shown by the example of a strong 6 4 earthquake of 1814 effect of insufficient use of the primary data source on completeness of earthquake catalogues is illustrated by the example of a strong m 7 0 event of 1859 analysis of the state of the art of historical earthquakes studies in eastern siberia allows us to propose the following activities in the near future 1 database compilation including initial descriptions of macroseismic effects with reference to their place and time of occurrence 2 parameterization of the maximum possible magnitude unlimited number of historical earthquakes on the basis of all the data available 3 compilation of an improved version of the parametric historical earthquake catalogue for east siberia with detailed consideration of each event and distinct logic schemes for data interpretation thus we can make the conclusion regarding the necessity of a large scale revision in historical earthquakes catalogues for the area of study

a refined age for the earliest opening of bering strait abstract biostratigraphically and chronostratigraphically important diatoms from the milky river formation alaska peninsula southwestern alaska imply an age range of 5 4 5 5 ma for the oldest north pacific cenozoic occurrence of the marine bivalve mollusk astarte which migrated from the arctic ocean into the north pacific when bering strait first flooded the data presented here are a refinement of the age range of 4 8 5 5 ma reported earlier and imply that bering strait first opened very near the end of the miocene at 5 32 ma

early pliocene fish remains from arctic canada support a pre pleistocene dispersal of percids teleostei perciformes percid remains from pliocene deposits on ellesmere island arctic canada are identified as a species of sander similar to the walleye and sauger of north america and the pike perch of europe and western asia they are named as a new species sander teneri these remains are the most northerly percid elements found to date and suggest the palaeoen vironment was significantly warmer in the pliocene than it is currently the fossil remains show the presence in north america of the family percidae as well as the genus sander prior to the pleistocene indicating a previously proposed pleistocene immigration from europe or asia can be discounted these fossils contradict an earlier hypothesis that percids in particular sander crossed from eurasia to north america in the pleistocene instead the fossils show percids were al ready in the area by the pliocene resume des restes de percides provenant de depots pliocenes de l o le ellesmere dans l arctique canadien sont attribues aune espece de sander semblable au dorejaune et au dorenoir d amerique du nord et au sandre d europe et d asie oc cidentale le nouveau nom d espece sander teneri leur est attribue ces restes constituent les elements de percides les plus nordiques trouvesace jour et portent acroire que le paleomilieu etait sensiblement plus chaud au pliocene qu il ne l est actuellement les restes fossiles demontrent que la famille des percidesd e meme que le genre sander etaient presents en amerique du nord avant le pleistocene ce qui invalide la these anterieurement proposee d une immigration pleistocene provenant d europe ou d asie l existence de ces fossiles vient contredire une hypothese anterieure voulant que les per cides et plus particulierement sander soient arrives en amerique du nord en provenance de l eurasie au pleistocene les fossiles montrent plutot que les percidesetaient dejapresents en amerique du nord durant le pliocene traduit par la redaction

regional scale integration of multiresolution hydrological and geophysical data using a two step bayesian sequential simulation approach significant progress has been made with regard to the quantitative integration of geophysical and hydrological data at the local scale for the purpose of improving predictions of groundwater flow and solute transport however extending corresponding approaches to the regional scale still represents one of the major challenges in the domain of hydrogeophysics to address this problem we have developed a regional scale data integration methodology based on a two step bayesian sequential simulation approach our objective is to generate high resolution stochastic realizations of the regional scale hydraulic conductivity field in the common case where there exist spatially exhaustive but poorly resolved measurements of a related geophysical parameter as well as highly resolved but spatially sparse collocated measurements of this geophysical parameter and the hydraulic conductivity to integrate this multi scale multi parameter database we first link the low and high resolution geophysical data via a stochastic downscaling procedure this is followed by relating the downscaled geophysical data to the high resolution hydraulic conductivity distribution after outlining the general methodology of the approach we demonstrate its application to a realistic synthetic example where we consider as data high resolution measurements of the hydraulic and electrical conductivities at a small number of borehole locations as well as spatially exhaustive low resolution estimates of the electrical conductivity obtained from surface based electrical resistivity tomography the different stochastic realizations of the hydraulic conductivity field obtained using our procedure are validated by comparing their solute transport behaviour with that of the underlying true hydraulic conductivity field we find that even in the presence of strong subsurface heterogeneity our proposed procedure allows for the generation of faithful representations of the regional scale hydraulic conductivity structure and reliable predictions of solute transport over long regional scale distances

relating lithofacies to hydrofacies outcrop based hydrogeological characterisation of quaternary gravel deposits abstract a considerable part of today s drinking water supplies in europe and north america rely on clean groundwater from gravelly valley aquifers of quaternary age the sedimentary architecture the distribution of lithofacies and of architectural elements in such heterogeneous deposits are of fundamental importance for the analysis of groundwater flow and contaminant transport as the aquifers are not directly accessible for observation representative outcrop analogues were used to study the sedimentology on a local scale conventional sedimentological classification schemes were adapted for the purpose of hydrogeological evaluations measurements of hydraulic properties were then used to define a set of 5 hydrofacies from 23 possible sediment lithofacies a digital photographic mapping procedure was developed to allow fast data acquisition in the field the sedimentologically interpreted outcrops were stored in a gis style database and thus allow the output for further sedimentological or hydrogeological analysis