high precision isotopic characterization of usgs reference materials by tims and mc icp ms the pacific centre for isotopic and geochemical research pcigr at the university of british columbia has undertaken a systematic analysis of the isotopic sr nd and pb compositions and concentrations of a broad compositional range of u s geological survey usgs reference materials including basalt bcr 1 2 bhvo 1 2 andesite agv 1 2 rhyolite rgm 1 2 syenite stm 1 2 granodiorite gsp 2 and granite g 2 3 usgs rock reference materials are geochemically well characterized but there is neither a systematic methodology nor a database for radiogenic isotopic compositions even for the widely used bcr 1 this investigation represents the first comprehensive systematic analysis of the isotopic composition and concentration of usgs reference materials and provides an important database for the isotopic community in addition the range of equipment at the pcigr including a nu instruments plasma mc icp ms a thermo finnigan triton tims and a thermo finnigan element2 hr icp ms permits an assessment and comparison of the precision and accuracy of isotopic analyses determined by both the tims and mc icp ms methods e g nd isotopic compositions for each of the reference materials 5 to 10 complete replicate analyses provide coherent isotopic results all with external precision below 30 ppm 2 sd for sr and nd isotopic compositions 27 and 24 ppm for tims and mc icp ms respectively our results also show that the first and second generation usgs reference materials have homogeneous sr and nd isotopic compositions nd isotopic compositions by mc icp ms and tims agree to within 15 ppm for all reference materials interlaboratory mc icp ms comparisons show excellent agreement for pb isotopic compositions however the reproducibility is not as good as for sr and nd a careful sequential leaching experiment of three first and second generation reference materials bcr bhvo agv indicates that the heterogeneity in pb isotopic compositions and concentrations could be directly related to contamination by the steel mortar pestle used to process the materials contamination also accounts for the high concentrations of certain other trace elements e g li mo cd sn sb w in various usgs reference materials

interpretation of slingram conductivity mapping in near surface geophysics using a single parameter fitting with 1d model1 electrical conductivity mapping is a prerequisite tool for hydrogeological or environmental studies its interpretation still remains qualitative but advantages can be expected from a quantitative approach however a full 3d interpretation is too laborious a task in comparison with the limited cost and time which are involved in the majority of such field studies it is then of value to define the situations where lateral variations are sufficiently smooth for a 1d model to describe correctly the underlying features for slingram conductivity measurements criteria allowing an approximate 1d inversion are defined these mainly consist of a limited rate of variation over three times the intercoil spacing in geological contexts where the weathering has generated a conductive intermediate layer between the underlying sound rock and the soil this processing can be applied to determine the thickness of the conductive layer from the apparent resistivity map when the other geoelectrical parameters are known the examples presented illustrate this application

spatial and temporal relationships between mid tertiary magmatism and extension in southwestern arizona cenozoic magmatism in southwestern arizona which is within the basin and range tectonic province occurred almost entirely between 15 and 25 ma volcanic rocks typically consist in ascending order of 1 a thin sequence of mafic to intermediate lava flows 2 voluminous felsic lava flows and pyroclastic rocks with minor to moderate amounts of intermediate to mafic lava flows and 3 basalt and andesite volcanic rock sequences rest disconformably on pre tertiary bedrock in most areas but locally overlie substantial coarse clastic debris that was deposited immediately before and during earliest magmatism prevolcanic clastic debris is interpreted as a consequence of local early normal faulting in most regions tilting related to extension began later and occurred during or after eruption of felsic volcanic rocks and before the end of younger mafic volcanism extension generally ended before about 17 ma except in a northwest trending belt adjacent to the relatively unfaulted and topographically elevated transition zone tectonic province which is adjacent to the colorado plateau rapid cooling of metamorphic core complexes and tilting of young basalts and coarse clastic rocks continued in this belt until as recently as 11 ma extension was extreme in this belt whereas it was generally moderate to slight in other parts of southwestern arizona large magnitude extension was not associated with areas of greatest igneous activity and rapid cooling and exhumation of core complexes postdated local magmatism these relationships are inconsistent with theories that relate genesis of metamorphic core complexes to magma intrusion in the upper crust except for young extension in this northwest trending belt there are no apparent regional migration trends for either magmatism or extension within southwestern arizona lack of substantial extension before magmatism and general lack of magmatism during youngest extension are inconsistent with the hypothesis that magmatism was the product of decompression melting during lithospheric extension the long duration and large magnitude of extension adjacent to the transition zone tectonic province and within an area of earlier crustal thickening are consistent with the hypothesis that extension was driven by the gravitational potential energy of elevated land mass and crustal roots regional magmatic heating apparently weakened the lithosphere and triggered extension but did not control extension locally

on the effectiveness of 2d electrical inversion results an agricultural case study electrical resistivity tomography was used in beauce france to assess the water extraction by corn plants evapotranspiration the acquired pseudosections show conductive anomalies under the plants a 2d inversion of measurements led us to identify clear resistive features associated with the water losses under the corn plant rows new models have been calculated with two different 3d algorithms finite difference and moment method to take into account 3d structure of the ground and to confirm that periodic resistive features may generate shifted apparent resistivity anomalies

layered and laterally constrained 2d inversion of resistivity data in a sedimentary environment quasi layered models often can represent the actual geology more accurately than smooth minimum structure models we present a 2d inversion scheme with lateral constraints and sharp boundaries lci for continuous resistivity data all data and models are inverted as one system producing layered solutions with laterally smooth transitions the models are regularized through lateral constraints that tie interface depths or thicknesses and resistivities of adjacent layers a priori information used to resolve ambiguities and to add for example geological information can be added at any point of the profile and migrates through the lateral constraints to parameters at adjacent sites similarly information from areas with well resolved parameters migrates through the constraints to help resolve areas with poorly constrained parameters the estimated model is complemented by a full sensitivity analysis of the model parameters supporting quantitative evaluation of the inversion result a simple synthetic model proves the need for a quasilayered 2d inversion when compared with a traditional 2d minimum structure inversion a 2d minimum structure inversion produces models with spatially smooth resistivity transitions making identification of layer boundaries difficult a continuous vertical electrical sounding field example from sweden with a depression in the depth to bedrock supports the conclusions drawn from the synthetic example a till layer on top of the bedrock hidden in the traditional inversion result is identified using the 2d lci scheme furthermore the depth to the bedrock surface is easily identified for most of the profile with the 2d lci model which is not the case with the model from the traditional minimumstructure inversion

calibration of the calcite water oxygen isotope geothermometer at devils hole nevada a natural laboratory abstract the 18 o of ground water 13 54 0 05 and inorganically precipitated holocene vein calcite 14 56 0 03 from devils hole cave 2 in southcentral nevada yield an oxygen isotopic fractionation factor between calcite and water at 33 7 c of 1 02849 0 00013 1000 ln calcite water 28 09 0 13 using the commonly accepted value of calcite water t of 0 00020 k 1 this corresponds to a 1000 ln calcite water value at 25 c of 29 80 which differs substantially from the current accepted value of 28 3 use of previously published oxygen isotopic fractionation factors would yield a calcite precipitation temperature in devils hole that is 8 c lower than the measured ground water temperature alternatively previously published fractionation factors would yield a 18 o of water from which the calcite precipitated that is too negative by 1 5 using a temperature of 33 7 c several lines of evidence indicate that the geochemical environment of devils hole has been remarkably constant for at least 10 ka accordingly a re evaluation of calcite water oxygen isotopic fractionation factor may be in order assuming the devils hole oxygen isotopic value of calcite water represents thermodynamic equilibrium many marine carbonates are precipitated with a 18 o value that is too low apparently due to a kinetic isotopic fractionation that preferentially enriches 16 o in the solid carbonate over 18 o feigning oxygen isotopic equilibrium

comment on first records of syn diagenetic non tectonic folding in quaternary thermogene travertines caused by hydrothermal incremental veining by billi et al tectonophysics 700 701 2017 60 79 abstract billi et al 2017 proposed a new interpretation for the origin and internal structure of thermogene travertine deposits on the basis of evidence from two quarries located in southern tuscany italy they interpreted some travertine beds as calcite veins and argued that undulating travertine beds formed by syn diagenetic i e non tectonic folding that was caused by laterally confined volume expansion caused by incremental veining they assumed that such a process causes changes to the rock properties including porosity reduction rock strengthening and age rejuvenation the interpretations by billi et al 2017 challenge and question the current understanding and interpretation of thermogene travertine deposits this understanding based on numerous studies since the 1980s is that these deposits form from thermal water flowing downslope and precipitating calcium carbonate here we explain how the comparison with active depositional systems is essential for the understanding the origin of structures in older inactive travertine deposits such as those studied by billi et al 2017 we further argue that the three dimensional setting of travertine deposits should be taken into account in order to discuss the possible development of secondary structures indeed travertine deposition on slopes typically leads to the formation of terraced morphologies with pools bordered by rounded rims and separated from each other by steep walls the resulting three dimensional structures can be misinterpreted as asymmetric folds in two dimensional views i e in saw cut walls of quarry in this paper we debate the interpretations offered by billi et al 2017 and their criteria to recognise syn diagenetic non tectonic folds in travertine deposits and explain why many of their ideas are questionable

variations in soil carbonate formation and seasonal bias over 4 km of relief in the western andes 30 s revealed by clumped isotope thermometry abstract carbonate clumped isotope thermometry provides a new method for investigating long standing questions regarding seasonal biases in soil carbonate formation and the relationship between soil carbonate formation temperatures recorded by clumped isotopes t 47 and surface temperatures we address these questions by comparing c o and clumped isotope data from holocene soil carbonates to meteorological and in situ soil monitoring data along a 170 km transect with 4 km of relief in chile 30 s this arid transect experiences a winter wet season and a 20 c range in mean annual air temperature we test the hypothesis that regardless of soil moisture conditions soil carbonates from arid regions record warm season biases and form in isotopic equilibrium with soil water and soil co2 below 3200 m precipitation falls as rain and soil carbonate t 47 values at depths 40 cm resemble summer soil temperatures above 3200 m precipitation falls as snow and t 47 values resemble mean annual soil temperatures soil carbonates from the highest site yield anomalous 18 o 13 c and t 47 values indicative of kinetic isotope effects consistent with cryogenic carbonate formation our findings 1 demonstrate that soil carbonate t 47 values from shallow 40 cm 3 highlight the role of the soil moisture regime in modulating the timing of soil carbonate formation which affects the resulting carbonate t 47 values and 4 show that soil carbonates from high elevation or high latitude sites may form under non equilibrium conditions these findings underscore the importance of understanding past soil moisture conditions when attempting to reconstruct paleotemperatures using carbonate clumped isotope thermometry

prospection of two circular bronze age ditches with multi receiver electrical conductivity sensors north belgium two types of electrical conductivity sensors were evaluated to prospect circular ditches surrounding former bronze age burial mounds complementing aerial photography the first sensor was based on the electrical resistivity er method while the second sensor was based on frequency domain electromagnetic induction fdem both sensors were designed with multiple receivers which measure several depth sensitivities simultaneously first the sensors were tested on an experimental site where a rectangular structure with limited dimensions was dug in a sandy soil the structure appeared as a higher conductivity anomaly in the low conductivity sand then both methods were applied on two bronze age sites with different soil properties which were discovered by aerial photography the first site in a sandy soil gave only very weak anomalies soil augering revealed that the ditch filling consisted of the same sandy material as the surrounding therefore this filling was not able to cause a high conductivity contrast due to its lower sensitivity to noise in the low conductive range the er sensor produced a more pronounced anomaly than the fdem sensor the second site was located on top of a ridge with a shallow substrate of tertiary coastal sediments the ditch was very clearly visible on the sensor maps as a conductive low at this location the soil augering revealed that the ditch was dug through an alternating clay sand layer and subsequently filled up with silty material from the topsoil overall the shallow receiver separation produced anomalies that were both stronger and that corresponded better to the geometry of the ditches the other receiver separations provided more information on the natural soil layering and in the case of the er array they could be used to obtain a cross section of the actual electrical conductivity with 2 d inversion modelling the results of this study proofed that conductivity sensors can detect bronze age ditches with varying contrast depending on the soil geomorphology moreover the sensor maps combined with soil observations by coring provided insight in the environmental conditions that influence the contrast of the anomalies seen on the aerial photographs and the sensor maps

substrate geology controlling different morphology sedimentology diagenesis and geochemistry of adjacent travertine bodies a case study from the sanandaj sirjan zone western iran abstract a travertine fissure ridge and travertine mound are situated 800 m from each other at the western margin of the active tectono volcanic sanandaj sirjan zone western iran despite their close proximity the two geobodies show a difference in morphology lithofacies lithotypes diagenesis and geochemistry petrographic analysis of the fissure ridge carbonates revealed homogeneous sparitic fabrics with dendritic structures reflecting precipitation under fast flowing conditions from calcite supersaturated spring water the mound carbonates are much more heterogeneous and display dominantly micritic fabrics with mainly volcanic clasts reflecting a lower energy flow regime and lower calcite saturation in contrast to the limited diagenetic overprint of the fissure ridge carbonates the more porous mound carbonates are affected by dissolution cementation and formation of mn fe oxide hydroxides attesting of a strong control on porosity by early diagenetic processes the widespread bright luminescent calcite phases especially in sparitic fabrics within both geobodies display high mn concentrations in calcite indicating suboxic precipitation conditions the overlapping 87sr 86sr signatures and 13c signatures point to a mixture of co2 that dominantly originated from dissolution of the marine carbonate qom formation oligo miocene the different 18o signatures indicate different upwelling systems caused by different substrate settings the fissure ridge formed on a hard and brittle limestone substrate with precipitation from dominantly subsurface sourced fluids the mound travertine formed on top of fairly unconsolidated and fractured volcanic strata the depleted 18o signatures and impure micrite dominated fabrics of the mound travertine reflect precipitation from thermal water that mixed with surrounding groundwater this difference is also reflected in a different calculated precipitation temperature that varies between 4 and 21 c for the mound versus 25 50 c for the fissure ridge our findings show that subsurface geology exerts a major control on precipitation processes resulting in differences in travertine morphology sedimentology diagenesis and geochemistry despite that the travertine bodies occur adjacent to each other

stable isotope geochemical study of pamukkale travertines new evidences of low temperature non equilibrium calcite water fractionation abstract in this paper we present the first detailed geochemical study of the world famous actively forming pamukkale and karahayit travertines denizli basin sw turkey and associated thermal waters sampling was performed along downstream sections through different depositional environments vent artificial channel and lake terrace pools and cascades of proximal slope marshy environment of distal slope 13 c travertine values show significant increase from 6 1 to 11 7 pdb with increasing distance from the spring orifice whereas the 18 o travertine values show only slight increase downstream from 10 7 to 9 1 pdb mainly the co 2 outgassing caused the positive downstream shift 6 in the 13 c travertine values the high 13 c values of pamukkale travertines located closest to the spring orifice not affected by secondary processes suggest the contribution of co 2 liberated by thermometamorphic decarbonation besides magmatic sources based on the gradual downstream increase of the concentration of the conservative na k cl evaporation was estimated to be 2 5 which coincides with the moderate effect of evaporation on the water isotope composition stable isotopic compositions of the pamukkale thermal water springs show of meteoric origin and indicate a local meteoric water line of denizli basin to be between the global meteoric water line craig 1961 and western anatolian meteoric water line imsek 2003 detailed evaluation of several major and trace element contents measured in the water and in the precipitated travertine along the pamukkale mm section revealed which elements are precipitated in the carbonate or concentrated in the detrital minerals former studies on the hungarian egerszalok travertine kele et al 2008a b 2009 had shown that the isotopic equilibrium is rarely maintained under natural conditions during calcite precipitation in the temperature range between 41 and 67 c in this paper besides the detailed geochemical analyses along downstream sections we present new evidences of non equilibrium calcite water fractionation in lower temperature range 13 3 to 51 3 c our measurements and calculations on natural hot water travertine precipitations at pamukkale and egerszalok revealed that the 18 o travertine is equal with the 18 o hco3 at the orifice of the thermal springs which means that practically there is no oxygen isotope fractionation between these two phases high rate of co 2 degassing with rapid precipitation of carbonate could be responsible for this as it was theoretically supposed by o neil et al 1969 thus for the determination of the deposition temperature of a fossil travertine deposit we propose to use the water bicarbonate oxygen isotope equilibrium fractionation instead of the water travertine fractionation which can result 8 9 c difference in the calculated values our study is the first detailed empirical proof of o neil s hypothesis on a natural carbonate depositing system the presented observations can be used to identify more precisely the deposition temperature of fossil travertines during paleoclimate studies

electromagnetic conductivity imaging emci of soil using a dualem 421 and inversion modelling software em4soil abstract one of the most popular geophysical methods currently being used to provide information about the spatial variation of soil properties is electromagnetic em induction this is because em instruments are easy to set up use and mobilise in addition the measured apparent electrical conductivity a ms m 1 has been shown to be useful in mapping soil e g clay and hydrological e g water holding capacity properties however in most of these studies the potential to model the stratigraphic nature of soil variation i e horizons and at discrete depth intervals has not been fully realised in this research we describe how a single frequency and multiple coil em instrument i e dualem 421 and an inversion algorithm em4soil can be used to generate a two dimensional model of the electrical conductivity ms m 1 the algorithm was evaluated using a acquired across an irrigated agricultural field in an extensive quaternary alluvial clay plain northwest of moree new south wales nsw australia in addition we conduct inversions of various combinations of a data we do this to compare and contrast the results that can be achieved using the various combinations of commercially available instruments we compare the inverted models of with measured soil properties such as clay content cation exchange capacity and the electrical conductivity of a one part soil to five part water ec1 5 dsm 1 and saturated soil paste ecp dsm 1 in general is shown to compare favourably with ecp in terms of identifying an optimal set of a data we found that whilst the akaike information criteria aic indicated that a dualem 1 and a dualem 421 configuration using only hcon provided the best balance between goodness and fit between and ecp the best reconstruction of and in terms of a 1 1 relationship with ecp is achieved using all six possible a measurements that can be obtained by a dualem 421

u pb geochronology and geochemistry of the mccoy mountains formation southeastern california a cretaceous retroarc foreland basin the timing of deposition of fluvial sediments now forming the 7 km thick mccoy mountains formation is one of the key uncertainties in reconstructing the mesozoic paleogeography of southern california and western arizona ion microprobe u pb geochronologic data for individual zircons from nine sandstones from the mccoy mountains type section and six associated igneous rocks provide significant new constraints on the tectonic setting and the timing of deposition within the northwest trending mccoy basin u pb zircon data from a metavolcanic rock of the underlying dome rock sequence in the palen mountains confirm that the mccoy mountains formation was deposited after regional middle to late jurassic arc magmatism u pb zircon data from a late cretaceous granodiorite intruding the formation in the coxcomb mountains confirm that the formation was deformed and metamorphosed prior to 73 5 1 3 ma populations of detrital zircons vary systematically with both rock type and stratigraphic height lithic arkoses predominantly derived from the west have consistently more abundant younger zircons than do litharenite sandstones predominantly derived from the north and the youngest zircons yield maximum depositional ages that decrease from 116 ma near the base to 84 ma near the top of the section the detrital zircon data permit a late jurassic age for the basal comparatively quartz rich sandstone however the data further suggest that 90 of the formation was deposited between middle early and middle late cretaceous time these results are consistent with the hypothesis that most of the mccoy mountains formation represents a retroarc foreland basin deposited behind the active evolving cretaceous cordilleran continental margin magmatic arc that lay to the west and in the foreland of the actively deforming cretaceous maria fold and thrust belt

mid to late cretaceous ductile deformation and thermal evolution of the crust in the northern dome rock mountains arizona abstract mid to late cretaceous basement involved deformation in the maria tectonic belt of southeastern california and west central arizona varies in style from low angle overthrusts to km scale fold nappes to establish the relationship between tectonite fabrics and thermal evolution of the rocks structural and petrographic analysis was conducted in the northern dome rock mountains where the two different styles converge a penetrative northeast dipping foliation forms the most conspicuous fabric in an 5 km wide zone of distributed ductile deformation within the broader zone of ductile deformation northeast dipping shear zones contain evidence for both southwest and northeast directed deformation textural analysis of mylonitic rocks reveals that southwest directed deformation occurred under prograde conditions whereas northeast directed deformation occurred under retrograde conditions southwest directed deformation resulted in tubular extreme sheath fold development on a kilometer scale in the footwall of a reverse sense shear zone northeast directed deformation cuts the map scale tubular fold and is inferred to have developed as a manifestation of gravitational collapse of rocks mechanically weakened by fluid infiltration and upper greenschist to lower amphibolite facies metamorphism we propose that the mode and degree of fluid infiltration rather than temperature or structural level alone controlled the style of deformation in the maria belt

pleistocene vertebrate faunas of the suttő travertine complex hungary numerous fossil remains vertebrates molluscs and plants were found in more than twenty sites of the sutt travertine complex during the last 150 years the majority of these remains were recovered from fissures of the travertine but also from the travertine and an overlying loess paleosol sequence the aims of this study were to review the fossil content to determine the stratigraphical positions of the various vertebrate faunas of sutt and provide paleoecological interpretation of the periods on the basis of their faunas and floras in addition this paper describes new faunas and floras from the sites sutt 16 20 and provides 14c dates for sutt 16 on the basis of the new uranium series isotope and optical dating osl the age of the travertine complex is middle pleistocene 235 21 314 45 ka mis 7 9 while the age of the loessepaleosol sequence in superposition of the travertine is middleelate pleistocene mis 2 mis 6 in contrast the fossils of the travertine indicated an older pliocene early pleistocene age a fissure sutt 17 and a red clay layer sutt 19 contained mammal faunas of early middle pleistocene age these results indicated the existence of older travertine in certain quarries hegyhati quarry cukor quarry sedimentological and osl data of well dated layers of the loess paleosol sequence sutt lps at sutt o allowed a correlation with the layers of sutt 6 the paleosol layer in the upper part of the sequence of sutt o 6 was correlated with a pedocomplex of the overlying loess paleosol sequence which was dated to mis 5c upper dark soil and mis 5e lower reddish brown soil the paleoecological analysis of the mammal and mollusc faunas supported the former interpretation of novothny et al 2011 inferring warm dry climate during the sedimentation of the upper layers and more humid climate for the lower layers however the fauna of the lower soil layer indicated cold climate so an age of mis 5d is suggested dating of the fissure faunas is based on similarity studies for some faunas this method cannot be used because of the low number of species on the basis of the species compositions and former interpretations these faunas originated mainly from sediments that were deposited under cold climatic conditions other fissure faunas were dated by ams 14c sutt 16 or by correlation with soil layers of sutt 6 according to these results most of the fissure faunas can be correlated with different phases of mis 5 however there are a younger mis 2 and an older early middle pleistocene fissure fauna also

are mid latitude slopes sensitive to climatic oscillations implications from an early holocene sequence of slope deposits and buried soils from eastern germany abstract on a straight slope within the lake catchment of kleiner tornowsee brandenburg germany a sequence of slope sediments has been deposited during the late glacial the early holocene and around cal 4 2 ka before today 800 500 and 300 years ago the chronology is based on 21 radiocarbon dates and 11 osl dates and a deposition model including the numerical data as well as stratigraphic information has been calculated with oxcal 4 1 a comparison of the woody taxa of charcoal particles n 566 embedded within the sediments with the known regional vegetation history confirmed the reliability of the dates according to the age volume and distribution the deposition of the early holocene sediments at ca 10 3 kyrs ca 9 5 kyrs and ca 8 2 to 7 7 kyrs before today strongly suggests an influence of known climatic deteriorations phases on geomorphologic processes cold and dry climatic conditions probably promoted wildfires in pinus dominated forests and therefore triggered the observed repeated slope instability in consequence mid latitude slope deposits provide a potential to reconstruct the geomorphological response to climatic events at a high spatial resolution in contrast the recorded mid to late holocene soil erosion phases on the slope have been triggered by land use activities apart from traditional environmental archives slope deposits provide valuable information about the vegetation and climate history

geochemical transect through a travertine mount a detailed record of co 2 enriched fluid leakage from late pleistocene to present day little grand wash fault utah usa abstract active and fossil endogenic travertine mounts scattered along the little grand wash fault are studied as records of quaternary co 2 enriched fluid leakage this study focusses on a particular area where a fossil mount formed in a near surface setting by successive circulation sealing episodes from late pleistocene to mid holocene and where a modern surface travertine is still being formed by a co 2 enriched fluid source the fossil mount is composed of horizontal and vertical veins whereby the vertical veins recorded numerous cycles of circulation sealing dissolution events and were used as conduits for the co 2 enriched fluid circulation from the depth to the surface or along sub horizontal fractures where successive precipitation events are recorded the modern travertine is being built at the surface by successive eruption of crystal geyser an anthropic geyser active since the 1930 s 13 c and 18 o signatures and u th datings ranging from 11 5 ky till present day allows calibrating in detail the co 2 enriched fluid leakage along a single fault segment and in a post glacial context as last glaciations in the study area took place 15 ky ago the dataset shows a high decrease of the oxygen stable isotope values till about 6 ky then the variations reflect a constant range until present day this tends to restrain the period of local increase of the meteoric water input in the aquifer that is sourcing the co 2 enriched water the fossil travertine represents a 7 ky long record of co 2 leakage above a natural reservoir from late pleistocene to mid holocene the flux of co 2 leakage through time and the total escaping volume have been computed and appears to be low in comparison with an anthropogenic leak provoked for instance by a non sealed well

towards a mechanical model for the formation of the pannonian basin abstract new maps showing crustal and lithospheric thickness variations in the pannonian basin and the surrounding east alpine carpathian and dinaric mountains have been prepared on the basis of recent seismic seismologic and electromagnetic data a map presenting miocene faults of regional significance has been also constructed for the same region by using a wealth of recently available national and or more local studies it is suggested that observed crustal and lithospheric structural contrasts have been controlled primarily by neogene kinematic history of the region kinematic history is characterized by the following main patterns 1 1 indentation by adria and large scale backthrusting in the southern alps 2 2 eastward escape and extension of the eastern alps 3 3 extensional collapse in the pannonian basin area 4 4 formation of broad wrench fault systems along strike in the dinarides and southern carpathians and the western carpathians with dextral and sinistral shear respectively 5 5 compression and accretion of the external thrust and fold belt in the eastern carpathians these kinematic patterns are thought to be interrelated and all are manifestations of the late stage evolution of an overthickened orogenic wedge in order to arrive at a better understanding of the mechanism of extension which formed the pannonian basin deep crustal seismic profiles hydrocarbon exploration reflection lines and borehole data have been analyzed in the little hungarian plain this plain represents the transition zone between the alps and the pannonian lowlands and the results are illustrated by eight interpreted cross sections one result of regional importance is the clear recognition that the transdanubian central range at the southeastern flank of the little hungarian plain is composed of alpine pre senonian thrust sheets this finding marks the end of a century of debate the allochthony of the substrata of the pannonian basin can be now considered proven another result of more general interest is that these cross sections document the mode of lithospheric extension preexisting compressional detachment planes reactivate as low angle normal faults and lead to tectonic unroofing of deeply buried metamorphic terranes characterized by ductile flow along subhorizontal lineation

hydrothermal fluids circulation and travertine deposition in an active tectonic setting insights from the kamara geothermal area western anatolia turkey abstract coexistence of thermal springs travertine deposits and tectonic activity is a recurring feature for most geothermal areas although such a certainty their relationships are debated mainly addressing on the role of the tectonic activity in triggering and controlling fluids flow and travertine deposition in this paper we present the results of an integrated study carried out in a geothermal area located in western anatolia turkey nearby the well known pamukkale area denizli basin our study focused on the relationships among hydrothermal fluids circulation travertine deposition and tectonic activity with particular emphasis on the role of faults in controlling fluids upwelling thermal springs location and deposition of travertine masses new field mapping and structural kinematics analyses allowed us to recognize two main faults systems nw and ne trending framed in the neogene quaternary extensional tectonic evolution of western anatolia a geo radar gpr prospection was also provided in a key area permitting us to reconstruct a buried fault zone and its relationships with the development of a fissure ridge travertine deposit kamara fissure ridge the integration among structural and geophysical studies fluids inclusion geochemical isotopic data and 230 th 238 u radiometric age determination on travertine deposits depict the characteristics of the geothermal fluids and their pathway up to the surface hydrological and seismological data have been also taken in account to investigate the relation between local seismicity and fluid upwelling as a main conclusion we found strict relationships among tectonic activity earthquakes occurrence and variation of the physical chemical features of the hydrothermal fluids presently exploited at depth or flowing out in thermal springs in the same way we underline the tectonic role in controlling the travertine deposition making travertine mainly banded travertine a useful proxy to reconstruct the seismological history of an area as well as the characteristics of the parent geothermal fluids adding an effective tool for geothermal exploration tasks

palaeoclimate interpretation of stable isotope data from lake sediment archives the isotope composition of authigenic and biogenic carbonates and diatom silica are commonly used as palaeoclimate proxies from lake sediments this article reviews the controls on the isotope composition of lacustrine skeletal and non skeletal deposits and illustrates how stable isotope studies contribute to an understanding of changes in temperature precipitation patterns evaporation and the carbon cycle it highlights the differences in the palaeoclimate potential of a wide range of lakes ranging from open to closed lake basins a large number of the case histories but not all are drawn from studies of temperate lakes from europe large closed lake systems in the tropics and elsewhere lose water predominantly through evaporation and contain sediments with variable and generally high 18o values fluctuations in the isotope composition of authigenic or biogenic minerals are mainly a function of long term changes in the precipitation evaporation ratio in contrast small open lakes which have a degree of through flow typically contain sediments with 18o values that vary by no more than a few these variations are generally ascribed to variations in temperature or the isotope composition of precipitation p from which either an annual or seasonally specific signal can be gained these types of lakes are common in northern europe and at high altitudes the interpretation of isotope data from a lacustrine succession requires a knowledge of the local processes that might control and modify the signal their effects need to be quantified and a robust calibration using the modern lake system is necessary to establish the relationship between the measured signal the isotopic composition of the host waters and climate

equilibrium vs kinetic fractionation of oxygen isotopes in two low temperature travertine depositing systems with differing hydrodynamic conditions at baishuitai yunnan sw china abstract in order to understand the behavior of oxygen isotopic fractionation and obtain more reliable paleoclimatic data from surficial travertine deposits the hydrochemistry carbonate precipitation rates and the temporal and spatial variations in 18 o values of the modern travertine in two low temperature travertine depositing systems canal and pool with differing hydrodynamic conditions at baishuitai yunnan sw china were investigated during the warm rainy season may 24 to november 2 in 2010 it was found that the oxygen isotopic composition of travertine in the two systems showed distinct controlling mechanisms mainly due to different carbonate precipitation rates and water residence times for the canal system with fast flow large deviations between the calculated and measured temperatures indicated that travertine precipitated out of isotopic equilibrium this was due to rapid carbonate precipitation with intense co 2 degassing 18 o travertine values and water temperature increased downstream 1 and 4 c respectively while 18 o water values remained relatively stable it was shown that the 18 o values of travertine in the canal system recorded the 18 o values of dissolved carbonates hco 3 which also increased along the canal controlled by rayleigh distillation effects in contrast in the pools system with slow flow oxygen isotopic equilibrium between dissolved carbonates hco 3 and h 2 o was achieved and the 18 o travertine values did not display spatial variations calculated water temperatures using the equilibrium fractionation factors of coplen 2007 were identical to the measured ones which indicates that travertine in such pools system is suitable for the reconstruction of paleo precipitating temperatures finally by comparing these two systems we have obtained a simple criterion to determine the suitability of travertine to estimate temperatures the 18 o value of baco 3 precipitated from water samples is compared with the theoretical 18 o value of dissolved carbonate calculated using water temperature and 18 o water to check if the oxygen isotopes of the dissolved carbonate are in equilibrium with the water

a multidisciplinary approach to understanding carbonate deposition under tectonically controlled hydrothermal circulation a case study from a recent travertine mound in the euganean hydrothermal system northern italy a multidisciplinary study was carried out on an upper pleistocene travertine mound montirone hill abano terme south of padova veneto italy with the aim of developing a comprehensive understanding of the processes interacting in structurally controlled thermal springs and the consequent deposition of thermal limestones the sedimentology geochemistry structural characteristics and hydrogeology of the mound which is associated with the euganean geothermal field and the related complex structural framework of the schio vicenza fault system were investigated a palaeo environmental model of the deposit has been reconstructed clarifying the connection between the travertine deposition and the regional structural setting calcium rich thermal waters rose from spring orifices estimated temperature from 54 c to 61 c based on geochemical calculations and produced a mound made of coalescent shield like bodies the dominant lime mudstone facies resulted from the accumulation of lime mud at the bottom of shallow crater like basins located on top of stacked cones soft sediment deformations affecting the lime mud sediment were most probably produced by the recurrent uprising of gas bubbles the overlying crystalline crusts were deposited on the flanks of the mound by waters overflowing from the vents with laminar flux a deep hydrothermal circuit with a long period of water rock interaction is supported by geochemical analyses furthermore a local extensional regime enhancing the migration of thermal fluids to the surface is inferred based on the results of the structural analysis carried out on the fault fracture mesh that affects the mound these results corroborate the well established relation among travertine deposits hydrothermal systems and fault systems and substantiate the structurally controlled conceptual model of the euganean hydrothermal system suggesting that both the thermal and the fault systems were active at least since 34 ka

hydrothermal co2 degassing in seismically active zones during the late quaternary natural co2 discharges are abundant in turkey as evident from ongoing deposition of recent terrace mound travertines and emplacement of significant travertine vein and breccia deposits in fractured damage zones of active fault systems we report high precision u series age data for the vein carbonates combined with important field observations and geochemical data to evaluate the travertine veining and co2 degassing history in seismically active areas field evidence suggests that travertine filled veins and associated breccias represent hydrothermal eruption products which probably formed by hydraulic fracturing in response to overpressure of co2 rich fluids stable isotope and ree data support the field observations and indicate that travertine veins formed as thermogene deposits from rapidly ascending co2 rich fluids travertine veins from the kirsehir geothermal field give u series ages in a range from 10 6 0 3 ka to 86 16 1 24 ka with a majority of ages failing between 10 6 0 3 and 11 3 0 2 ka vein samples from the pamukkale geothermal field yield u series ages between 21 1 0 1 ka and 73 6 0 6 ka two major age groups are evident in pamukkale that cluster coherently around 21 ka and 25 ka a large number of travertine veins we dated by high precision u series technique coincide with times of cold dry climate events this is different from surface sinter deposits in geothermal fields which more frequently form during warm and wet periods we propose that a significant reduction in surface discharge of co2 by spring or geothermal waters during dry climate periods may promote oversaturation of co2 in deep reservoirs host rock fracturing in response to seismic shaking and fluid overpressure results in rapid exsolution and expansion of the dissolved gas and may lead to hydrothermal eruptions crown copyright c 2009 published by elsevier b v all rights reserved

the differential parameter method for multifrequency airborne resistivity mapping helicopter em resistivity mapping began to be accepted as a means of geologic mapping in the late 1970s the data were first displayed as plan maps and images some 10 years later sectional resistivity displays became available using the same pseudolayer half space resistivity algorithm developed by fraser and the new centroid depth algorithm developed by sengpiel known as sengpiel resistivity sections these resistivity depth images proved to be popular for the display of helicopter electromagnetic em data in conductive environments a limitation of the above resistivity and depth algorithms is that the resulting sengpiel section may imply that the depth of exploration of the em system is substantially less than is actually the case for example a target at depth may be expressed in the raw data but its appearance on the sengpiel section may be too shallow which is a problem with the depth algorithm or it may not even appear at all which is a problem with the resistivity algorithm an algorith

high precision and high resolution carbonate 230th dating by mc icp ms with sem protocols abstract to facilitate the measurement of u th isotopic compositions suitable for high precision and high resolution 230th dating of coral and speleothem carbonates secondary electron multiplier sem protocol techniques for multicollector inductively coupled plasma mass spectrometry mc icp ms have been developed the instrumental sensitivities are 1 2 with a precision of 1 2 2 for abundance determination of 50 200 fg 234u 1 4 ng 238u or 230th this method features chemistry refinements improvements to procedural and instrumental blanks spectral inference reductions and careful consideration of non linear sem behavior measurement consistency of this mc icp ms combined with previous mass spectrometric results on u th standards and a variety of carbonates demonstrates the validity of the sem protocol method for fossil corals a routine u th isotopic determination at permil level precision requires only 10 50 mg of carbonate as little as 200 mg of young coral with an age of less than 20 yr can be dated with a precision of 0 3 0 8 yr about 20 200 mg speleothem samples with sub ppm to ppm u are required to earn a 5 precision on ages from 5 to 100 kyr requirement of small sample size 10 100s mg carbonate can permit high temporal resolution to date speleothems with slow growth rates i e 1 10 mm kyr this high precision 230th chronology is critical to accurately establish age models date events and splice geochemical proxy time series records from multiple samples in the fields of paleoclimatology and paleoceanography the u th isotopic determination techniques described here can also be applied to different environmental samples such as waters rocks and sediments

tertiary brittle faulting and stress field evolution in the gerecse mountains northern hungary abstract the gerecse mountains of the transdanubian range in northern hungary have suffered polyphase deformation during the tertiary the evolution of the stress fields was determined by the detailed structural survey of the area the statistical analysis of microtectonic observations the mapping and reinterpretation of fault pattern and the study of basin stratigraphy and geometry the stress fields show an apparent clockwise rotation from eocene until quaternary times three main phases were reconstructed during the eocene early oligocene e w to ene wsw oriented compression and perpendicular tension affected the area the formation and evolution of several sedimentary basins were controlled by fault systems activated by this phase after a period of intensive erosion in the early oligocene the stress field rotated approx 30 40 nw se directed compression and ne sw trending tension existed during the late oligocene and early miocene after correction with palaeomagnetic data an original palaeogene 1 orientation is deduced nne ssw reflecting the collisional processes of europe and the apulian microplate the middle miocene to pliocene period was characterised mainly by extensional deformation the direction of the minimal stress axis 3 varied between e w and nw se the characteristic clockwise rotation pattern of the tertiary palaeostress fields in the gerecse mts is explained by the combined effect of the regional stress field changes in the carpatho pannonian region and the rotation of the north pannonian unit

origins of elements building travertine and tufa new perspectives provided by isotopic and geochemical tracers fluid rock interaction represents a major process in the formation of calcitic or aragonitic travertine and tufa catt in most cases catt is associated to limestone dissolution somewhere along the hydrogeological pathway however a wide array of other substratum basalts rhyolites carbonatites ultramafics granites dolomites evaporites can act as potential source of elements involved in the formation of catt this study reports on the evaluation of potential geochemical tracers linking catt to their substratum and unravelling the origin of elements a large database was established from available literature data as well as new data acquired in the frame of this study for a set of modern to recent catt ligurian ophiolites italy the chaine des puys limagne graben and paris basin france reunion island indian ocean jebel oust tunisia four most reliable tracing methods are identified 1 13c and 18o cross plot allows distinguishing epigean min 13c 27 2 max 13c 0 9 mean 13c 12 3 for n 314 from hypogean systems min 13c 4 max 13c 11 7 mean 13c 2 87 for n 198 very low 13c values 4 associated to negative 13c values are specifically indicative of an ultramafic source rock 2 barium and strontium cross plot helps to discriminate different groups of source rocks amongst the hypogean catt i source rocks composed of mixed limestones evaporites and dolomites are characterised by low barium 400 ppm contents ii mafic and granitic source rocks are undifferentiated and display similar barium from 15 to 930 ppm and high strontium 200 ppm contents iii the carbonatite group is characterised by its exceptional high barium and strontium values in epigean catt a pure limestone source rock usually relates to very low barium and strontium contents 50 ppm 3 relatively high beryllium content 30 ppm in catt seems to indicate a pure granitoid source 4 high chromium concentrations 20 ppm are systematically documented in modern catt located on an ultramafic substratum the definition of diagnostic compositional fields for actively forming or recently formed catt is influenced by many factors including water composition water temperature dissolved gas composition and concentration biological activity position in the sedimentary body and early diagenesis in addition to substratum lithology however the results of this study illustrate that despite these many factors the combined use of ba sr be cr 13c and 18o may be valuable to discriminate the rock lithology prevailing in the hydrogeological or palaeo hydrogeological reservoir of catt

aragonite laminae in hot water travertine crusts rapolano terme italy small 5 30 m aggregates of aragonite needles occur in calcite crystal crusts of present day hot water slope travertines at rapolano terme in tuscany italy the aggregates are mainly concentrated in irregular wispy and dark laminae which cross cut calcite crystal feathers to create a pervasive millimetre scale banded appearance in the deposit they also occur less commonly scattered irregularly through the calcite layers the aragonite needle aggregates are in the form of crosses fascicles sheaf shaped bundles or dumbbell shaped rosettes and spherulites locally irregular masses of needles also occur the fascicles rosettes and spherulites have hollow centres which resemble microbial components fungal spores bacterial colonies and pollen suggesting that the aragonite crystals are biotically nucleated the lamination is interpreted to reflect diurnal control stimulation of microbial activity during daylight concentrates cells in laminae and promotes aragonite calcification calcite feather crystals although traversed by the aragonite aggregate laminae have a clear appearance under the light microscope they form more or less continuously through the diurnal cycle by abiotic precipitation the constant association of aragonite with organic nuclei irrespective of whether the latter are in laminae or scattered through the calcite layers supports a biotic control on aragonite formation lamination in pleistocene travertines is superficially similar to that in the present day deposits but is diagenetically altered in the pleistocene deposits the calcite feathers appear dark under the light microscope and the aragonite aggregates where they are not altered to dark calcite are dissolved together with parts of the adjacent spar calcite and therefore appear light coloured

continental carbonates as a hydrocarbon reservoir an analog case study from the travertine of saturnia italy the pleistocene saturnia travertine central italy represents a possible analog of the pre salt continental carbonate reservoirs discovered in the santos and other basins in the south atlantic margin of brazil two subhorizontal travertine tabular bodies several tens of meters thick and extending over an area of have been studied in two quarries facies variations and associated petrophysical properties were reconstructed applying a multidisciplinary approach the saturnia travertine formed from a warm water spring is composed of various stacked carbonate banks separated by subaerial erosive phases and paleosols the lacustrine tabular bodies terraces and sills are made of crystalline crust shrub pisoid paper thin raft coated bubble reed and lithoclast breccia facies the from 4 to 8 supports an interpreted volcanic mantle source whereas the from 9 to 5 is in agreement with warm meteoric waters the ratio isotopic signature indicates a carbonate from dissolution of deep seated carbonates the facies reservoir properties were studied via porosity and permeability analysis of plugs three dimensional x ray computer tomography as well as image analysis on microscale under thin section and macroscale on large rock slabs to define various porosity indices a strong heterogeneity of the petrophysical properties and variable connectivity were observed porosity from 4 to 30 and permeability up to hundreds of md but no compartmentalization of the carbonate bodies is present

origin and diagenesis of quaternary travertine shrub fabrics rapolano terme central italy millimetre to centimetre sized arborescent shrub like calcite precipitates are common constituents of hot water travertine shallow pool deposits of quaternary age at rapolano terme tuscany italy in the presently forming travertines the shrubs consist of apparently random associations of i micrite aggregates and ii subhedral to euhedral rhombic spar crystal aggregates in thin section the micrite aggregates appear dark and the spar rhomb aggregates light giving the shrubs a mottled appearance travertines are basically produced by caco3 precipitation due to degassing and evaporation of the spring waters although biological influence may also stimulate precipitation the formation of masses of erect shrubs rather than dense crystal crusts that form on slopes is probably due to limited water flow in the pool environments microbes including bacteria and diatoms are important influences on shrub microfabric and external shape the micrite aggregates are associated with bacteriform bodies seen as tiny rods and spheres the micrite precipitates around these bodies and in adjacent biofilm spar rhomb precipitation appears to be external to the biofilm and may be related to the presence of diatoms which are locally closely associated with the spar rhombs although an essentially inorganic origin particularly for the more euhedral rhombs cannot be ruled out in the older quaternary travertines the original microfabric of the shrubs has been diagenetically altered the original mottled appearance of the shrubs has become uniformly dark and micritic and the evidence for the dual micritic and spar rhomb origin of the shrubs is obscured or destroyed spar micritization of the shrubs is probably due to abiotic and locally biotic dissolution previous studies did not recognize the diagenetic micritization and attributed shrub formation entirely to bacterial activity

acoustic properties in travertines and their relation to porosity and pore types abstract sonic velocities of pleistocene travertines were measured under variable confining pressures combined with petrographical characteristics and petrophysical data i e porosity permeability and density it was determined that travertine porosity pore types and cementation control compressional wave vp and shear wave velocity vs at 40 mpa confining pressures vp ranges between 3695 and 6097 m s and vs between 2037 and 3140 m s velocity variations in travertines are as with all carbonates primarily linked to sample heterogeneity i e differences in fabric texture and porosity they thus not necessarily emanate from changes in mineralogy or composition body wave velocities have a positive correlation with sample density and an inverse correlation with porosity the travertines sampled in extensional settings with normal faulting activity define a specific compressional wave velocity y axis versus porosity x axis equation i e log y 0 0048x 3 7844 that differs from the vp porosity paths defined by marine carbonates acoustic wave velocities are higher for travertines than for marine carbonates travertine precipitates form rigid rock frames often called framestone with large primary pores marine carbonates on the other hand often consist of cemented transported sediments resulting in a rock frame that permits slower wave propagation when compared to the continental limestones acoustic velocity variations are linked to variations in pore types mouldic pores macropores show faster wave propagation than expected from their total porosities microporosity interlaminar and interpeloidal porosity result in slower acoustic velocities framework pores and micro moulds are associated with lowered acoustic velocities while vug porosity is found above on and below the general velocity porosity trend not only the pore type but also pore shapes exert control on body wave velocities cuboid and rod like pore shapes increase the velocity while plate and blade like pore shapes have a negative effect on the velocity the study demonstrates how seismic sections in travertine systems can contain seismic reflections that are not caused by non carbonate intercalations but relate to geobody boundaries in which the seismic expression is function of porosity pore types and shapes this study provides and relates petrophysical data i e porosity permeability and acoustic velocities of travertines and is of importance for the interpretation of seismic reflection data in subsurface continental carbonate reservoirs

spatial heterogeneity of high resolution chalk groundwater geochemistry underground quarry at saint martin le noeud france chalk groundwater is an important aquifer resource in france because it accounts for a production of 12 million m3 y 1 with a large proportion reserved for drinking water processes occurring in the unsaturated zone uz and the overlying superficial formations have a high impact on chalk groundwater geochemistry and require better understanding the study site is a former underground chalk quarry located near beauvais france that extends over 1200 m in length at a depth ranging from 20 to 30 m the water table intersects the cavity creating 15 underground lake that give access to the chalk groundwater lakes geochemistry has been studied water samples were collected in july 2013 and major ion concentrations were analyzed uz and clay with flints thickness above each lake were estimated qualitatively using an electromagnetic sensor em31 and underground gps the results unexpectedly showed that groundwater quality varied widely in spatial terms for both allochthonous and autochthonous ions e g hco3 ranged from 2 03 to 4 43 meq l 1 no3 ranged from 0 21 to 1 33 meq l 1 principal component analysis indicated the impact of agricultural land use on water quality with the intake of no3 as well as so42 cl and ca2 chalk groundwater geochemistry is compared with the nature and structure of the uz we highlight correlations 1 between thick clay with flints layers and the ions mg2 and k and 2 between uz thickness and na in conclusion this paper identifies various ion sources agriculture clay with flints and chalk and demonstrates different processes in the uz dissolution ionic exchange and solute storage

sedimentology three dimensional geobody reconstruction and carbon dioxide origin of pleistocene travertine deposits in the ballik area south west turkey the denizli basin in the west anatolian extensional province in western turkey is well known for its numerous travertine occurrences a combined sedimentological diagenetic and geochemical investigation is executed on the ece and faber travertines of the ballk area the largest travertine site in the denizli basin the first aim of this study is the reconstruction of a three dimensional geo model in combination with a detailed sedimentological description from fabric to lithotype lithofacies and geobody scale with a focus on integrating pore typing the second aim involves the delineation of the co2 origin of ancient travertine precipitating waters peloidal phyto and dendritic lithotypes dominate the studied travertines and honeycomb and bacteriform shapes and encrusted bacterial or fungal filaments related to their fabrics suggest a microbial influence the environment of travertine precipitation evolved from dominantly sub aqueous as represented by the sub horizontal and biostromal reed travertine facies to dominantly sub aerial in a thin water film resulting in the cascade waterfall and biohermal reed travertine facies a general progradation of the travertine mound is indicated by the occurrence of stacked waterfall travertines this results in sigmoidal clinoforms inside a general mound boundary configuration strontium and oxygen carbon isotope signatures of the travertines point to a mixing mechanism of palaeofluids with deeply originated heavy carbon co2 with lighter carbon co2 of shallow origin these deposits can thus be considered as endogenic travertines carbonates of the lycian nappes acted as main parent carbon source rocks the relative contribution of the lighter carbon isotopes is most likely to have originated from organic matter or soil co2 this study provides a unique three dimensional insight into the ballk travertine architecture that potentially can be used as an analogue for subsurface travertine reservoirs worldwide and illustrates the importance of the combined use of c 13 and sr 87 sr 86 signatures in the delineation of the co2 origin of travertine precipitating waters

origin of carbon in fumarolic gas from island arcs abstract we have measured 3 he 4 he ratios 13c values and co 2 3 he ratios of fumaroles and hot spring gases in three volcanic areas in japan the 3 he 4 he ratios 13c values and co 2 3 he ratios vary from 02 05 ratm 9 7 to 2 7 and from 7 74 109 to 1 18 1011 respectively based on these data and those in the literature we present the first quantitative estimates of the upper mantle sediment and limestone including slab components in co2 of volcanic and hydrothermal fluids from subduction zones taking compiled c isotopic data of limestone and organic sediment assuming that the co 2 3 he ratio and 13c value of mid ocean ridge basalt morb are representative of the upper mantle component and that later isotopic and elemental fractionations are minimal it is possible to deconvole each fraction of c on the basis of simple mixing equations up to 20 of the carbon in high temperature volcanic gases in subduction zones is derived from a morb type source while the major fraction of the gases is attributable to co2 produced by decarbonation of subducted marine limestone and slab carbonate

time domain magnetization of soils vrm experimental relationship to quadrature susceptibility a comparison is made between measurements with a multichannel bipolar pulsed induction meter pim and measurements made with a phase sensitive susceptibility bridge on more than 211 soil samples from a variety of archaeological sites in europe eddy currents originating from the decay of viscous remanent magnetization vrm were measured with the pim the in phase and out of phase q magnetic mass susceptibilies were measured with the susceptibility bridge viscous remanent magnetization was measured through eight time sampling intervals on the pulsed induction meter and the linearity of vrm for selected samples was tested at various field strengths 200 to 2300 t it is believed that this extension of the reversible range indicates a high coercive strength of the magnetic grains in the soil samples involved whatever the origin of the soil sample a constant decay of vrm with time was observed between 56 and 417 s after switching off the inducing field this relation is shown to be a power law wi

theoretical analysis of long offset time lapse frequency domain controlled source electromagnetic signals using the method of moments application to the monitoring of a land oil reservoir 1 we present a sensitivity study applied to water front monitoring of an onshore oil reservoir using a remote controlled source electromagnetic method csem with electric dipoles and a borehole to surface configuration we have developed an optimized and parallelized code based on the method of moments in order to study the influence of several static or time varying background uncertainties on the time lapse csem signal also called 4 d csem analysis of the relative and absolute variations in phase or quadrature of the time lapse signal induced by the fluid substitution process inside the reservoir has shown that the vertical electric dipole allows the shape of the water front to be monitored while remaining less sensitive compared to a horizontal electric source dipole to the total volume of substituted fluid we have examined the influence of missed anomalies 1 d 3 d with more or less conductive properties near to the ground surface or the reservoir and with or without time varying properties in most cases the 4 d signal behaves like a reliable filter canceling almost all response anomalies however it can also lead to strong local perturbations of the time lapse signal we have also shown that in the presence of steel cased boreholes at the source location or with outlying steel cased boreholes the recording of exploitable data does not present insurmountable difficulties at low frequencies 1 hz and for a dense array of surface receivers these positive results with csem monitoring suggest that minimal coarse time 3 d explorations should be used to ensure reliable interpretation of the monitored data

dissected hydrologic system at the grand canyon interaction between deeply derived fluids and plateau aquifer waters in modern springs and travertine geochemical study of water and gas discharging from the deeply incised aquifer system at the grand canyon arizona provides a paradigm for understanding complex groundwater mixing phenomena and quaternary travertines deposited from cool springs provide a paleohydrologic record of this mixing geochemical data show that springs have marked compositional variability those associated with active travertine accumulations deeply derived endogenic waters are more saline richer in co2 and elevated in 87sr 86sr relative to springs derived dominantly from surface recharge of plateau aquifers epigenic waters endogenic waters and associated travertine are preferentially located along basement penetrating faults we propose a model whereby deeply derived fluids are conveyed upward via both magmatism and seismicity our model is supported by 1 gas analyses from spring waters with high he ar and he n2 and 3he 4he ratios indicating the presence of mantle derived he 2 large volumes of travertine and co2 rich gases in springs recording high co2 fluxes and 3 87sr 86sr in these springs that indicate circulation of waters through precambrian basement geochemical trends are explained by mixing of epigenic waters of the colorado plateau aquifers with different endogenic end member waters in different tectonic subprovinces endogenic waters are volumetrically minor but have significant effects on water chemistry they are an important and largely unrecognized component of the hydrogeochemistry and neotectonics of the southwestern united states

fracture networks and strike slip deformation along reactivated normal faults in quaternary travertine deposits denizli basin western turkey abstract the denizli basin in the west anatolian extensional province in western turkey is known for its numerous quaternary travertine occurrences travertine morphology is often dependant on the relative position of the deposition with respect to basin bounding faults the travertine occurrences examined in this study are situated at the intersection of the locally e w oriented denizli basin and the adjacent ne sw oriented baklan graben in the ne based on an extensive field campaign including lidar scanning several high resolution fault fracture maps of five large quarries 300 m in length and 60 m in height are constructed in which this world class travertine deposit is currently excavated a structural analysis is performed in order to determine the tectonic overprinting of the travertine body and to derive the stress states of the basin after travertine deposition the mostly open non stratabound joints are several tens of metres long and often bifurcate creating a dense fracture network minor infill of the joints resulted in the presence of a few colour banded calcite veins based on the e w ne sw and nw se orientation of three dominant joint sets it is concluded that the joint network is caused by local n s extension alternated by nw se and ne sw extension exemplifying the presence of stress permutations in the quaternary high angle e w to wnw ese faults cross cut the quarries faults are filled with travertine debris and clastic infill of above lying sedimentary units indicative of the open nature of the faults the specific e w fault orientation in the locally e w trending denizli basin indicates that they initiated as normal faults a paleostress inversion analysis performed on kinematic indicators such as striations on the clayey fault infill and the sinistral displacement of paleosols shows that some of the normal faults were reactivated causing left lateral deformation in a transient strike slip stress field with a ne sw oriented 1

stable isotopic compositions of recent freshwater cyanobacterial carbonates from the british isles local and regional environmental controls recent 50 years old freshwater cyanobacterial carbonates from diverse environments streams lakes waterfalls throughout britain and ireland were analysed for their stable carbon and oxygen isotope compositions the mean 18o value of 5 9 pdb for river and stream data represents calcite precipitation in equilibrium with the mean oxygen isotopic composition of precipitation in central britain 7 5 smow assuming a mean water temperature of 9 c the mean 18o of lake data 4 5 pdb is statistically different reflecting the effects of residence time and or variations in the oxygen isotopic composition of rainfall carbon isotopes have wide variations in both fluviatile and lake data sets 3 to 12 pdb these variations are principally controlled in the fluviatile samples by contribution of isotopically light soil zone carbon relative to isotopically heavier carbon from limestone aquifer rock dissolution lake samples have the heaviest carbon isotope values reflecting a trend toward isotopic equilibrium between atmospheric co2 and aqueous hco 3 we infer that isotopic compositions of ancient cyanobacterial carbonates should also record environmental information although the effects of stabilization and diagenesis on primary 18o values will need careful consideration primary carbon isotope compositions should be well preserved although in marine samples values will be buffered by the isotopic composition of aqueous marine bicarbonate

classification and environmental models of cool freshwater tufas abstract tufa deposits are common in the quaternary record facies developments are dependent upon localised carbonate precipitation generally these take the form of phytoherm build ups together with associated detrital deposits derived from disagragation of the former phytoherm cements differ from speleothems and floe calcite accumulations in being biologically mediated or modified this paper recognises the following five types perched spring line cascade fluviatile paludal and lacustrine facies each type is composed of distinctive constructional and detrital sediment associations these unique sediment combinations are the product of an interplay between angle of slope water discharge rate standing water bodies phytal and microbial colonization and ambient temperature the proposed models will be of value in the interpretation of ancient and partially exposed tufas

stratigraphic relations and u pb geochronology of the upper cretaceous upper mccoy mountains formation southwestern arizona a previously unrecognized angular unconformity divides the jurassic and cretaceous mccoy mountains formation into a lower and an upper unit in the dome rock mountains and livingston hills of western arizona the lower unit of the mccoy mountains formation consists of generally fine grained quartzose and volcaniclastic strata that were deposited after cessation of middle jurassic explosive volcanism the basal contact of the lower unit is disconformable in most places but locally it has been interpreted to be gradational with the underlying silicic volcanic rocks the upper unit is a fining upward sequence of quartzo feldspathic and arkosic conglomerate and sandstone that records uplift of a northern source terrane a tuff in the lower part of the upper unit has a u pb crystallization age of 79 2 ma late cretaceous rocks of the lower unit are deformed by pre 80 ma thrust faults of the generally southward vergent maria fold and thrust belt which bounds the outcrop belt of the mccoy mountains formation on the north the upper unit is exposed only south of the fold and thrust belt we interpret the intraformation unconformity in the mccoy mountains formation to have developed where rocks of the lower unit were deformed adjacent to the southern margin of the maria fold and thrust belt the upper unit of the formation is interpreted as a foreland basin deposit that was shed southward from the actively rising and deforming fold and thrust belt the apparent absence of an equivalent unconformity in the mccoy mountains formation in adjacent california is presumably a consequence of the observed westward divergence of the outcrop belt from the fold and thrust belt continued southward shortening deformed the entire formation under greenschist and locally amphibolite facies conditions soon after the upper unit was deposited tectonic burial beneath the north vergent mule mountains thrust system in the latest late cretaceous 70 ma marked the end of mesozoic contractile deformation in the area

uranium series dating of travertine from suttő implications for reconstruction of environmental change in hungary abstract terrestrial carbonate formations such as travertines speleothems and lake sediments are important archives of terrestrial climate forcing at the sutt section in hungary a complex succession of travertine is covered by a loess palaeosol sequence both are high resolution terrestrial archives of climate and environment change uranium series 230th u dating was carried out to set up a more reliable chronological frame for the travertine as the growth of travertine is very complex pore cements may cause serious problems for precise dating the state of alteration of primary spar and micrite was characterised by microscopic cathodoluminescence and microprobe analyses the travertine from sutt showed homogeneous phases of primary calcite minor micropores and rare pore cements the carbon isotopic composition indicates that the source of carbon was a mixture of atmospheric and soil derived co2 calculated water temperatures based on oxygen isotope data range from 22 c to 31 c an attempt to provide an independent relative dating approach by palaeomagnetic techniques failed 230th u ages were determined applying an isochron approach using the leachate leachate method as the travertine deposits have a dense structure the bulk sampling method was successfully applied in determining uranium series ages with much higher precision than former studies with alpha spectrometry travertines from sutt yielded mid pleistocene ages ranging from the antepenultimate glacial to the penultimate interglacial 310 240 ka these results are in agreement with those from optically stimulated luminescence osl dating and amino acid racemisation aar dating of the overlying sediment indicating at least an mis 7 age for the travertine

chemical and stable isotope composition of recent hot water travertines and associated thermal waters from egerszalok hungary depositional facies and non equilibrium fractionation abstract combined petrographical mineralogical geochemical and stable isotope analyses were conducted on an actively forming egerszalok travertine mound to determine the factors that govern carbonate precipitation and thus influence the use of travertines in paleoclimate reconstruction stable isotope analyses of oxygen carbon and hydrogen demonstrate both biological and abiological factors to control travertine deposition processes of morphology related outgassing had major effects upon isotopic composition continuous co 2 degassing and temperature change of the thermal water between the spring orifice and distal parts of the system caused stable carbon and oxygen isotope compositions of the precipitating travertines to increase from 2 7 to 4 3 relative to v pdb and from 10 5 to 14 7 relative to v smow respectively the travertines at the spring orifice t 67 c are composed of almost pure calcite with a 13 c value of 2 7 relative to v pdb enabling classification as intermediate between thermometeogene and thermogene in lower temperature water away from the spring orifice various amounts of aragonite 5 35 with higher sr concentrations precipitate from solution this phenomenon is exceptional in hot spring carbonate deposits and could be explained by fast carbonate precipitation due to the morphology related outgassing oxygen and hydrogen isotope measurements of the thermal water confirmed evaporation to be causing limited kinetic isotope fractionation however 18 o values of the travertine do show isotope shifts away from the equilibrium fractionation curve which is most probably related to the rapid calcite precipitation and transportation along the flow path our data closely follow the temperature 18 o calcite water relationship observed for other travertine localities this is slightly displaced from the experimental curve and determines an empirical travertine curve our study shows that this shift may result in an approximately 8 c difference in paleotemperature calculations depending upon which fractionation curve is used

calcite veining and feeding conduits in a hydrothermal system insights from a natural section across the pleistocene golemezli travertine depositional system western anatolia turkey abstract linking the architecture of structural conduits with the hydrothermal fluids migrating from the reservoir up to the surface is a key factor in geothermal research a contribution to this achievement derives from the study of spring related travertine deposits but although travertine depositional systems occur widely their feeding conduits are only rarely exposed the integrated study carried out in the geothermal golemezli area nearby the well known pamukkale area denizli basin western anatolia turkey focused on onyx like calcite veins banded travertine and bedded travertine well exposed in a natural cross section allowing the reconstruction of the shallower part of a geothermal system the onyx like veins represent the thickest vein network 150 m so far known new field mapping and structural kinematic analyses allowed to document a partially dismantled travertine complex bedded travertine formed by proximal fissure ridges and distal terraced pools depositional systems the banded calcite veins wnw trending and up to 12 m thick developed within a 200 m thick damaged rock volume produced by parallel fault zones th u dating indicates a long lasting middle late pleistocene fluids circulation in a palaeo geothermal system that due to its location and chemical characteristics can be considered the analogue of the nearby still active pamukkale system the isotopic characteristics of the calcite veins together with data from fluid inclusions analyses allow the reconstruction of some properties i e temperature salinity and isotopic composition and processes i e temperature variation and intensity of degassing that characterized the parent fluids and the relation between degassing intensity and specific microfabric of calcite crystals elongated microsparite micrite bands controlled by changes fluctuations of the physico chemical fluid characteristics

modelling of the construction of the rhone alluvial plain since 15 000 years bp a numerical model presented here develops a three dimensional image of alluvial media on an elementary scale significant for groundwater flow modelling the model was tested on the alluvial plain of the rhone river france on a scale of several kilometres and from geomorphological observations and dating reproduced the construction of this alluvial plain from 15 000 years bp to the present the history of the alluvial plain during the late glacial and holocene periods is summarized through most of this time the river rhone has maintained a braided pattern with the exception of two incising phases with a meander pattern the model does not use any physically based equations or water representation the main processes governing the construction of the plain are modelled by simple rules chosen according to geometrical or empirical laws taken from the literature or as modelling assumptions using multi agent concepts of distribution and interaction of elementary entities these sedimentary rules are applied to sediment entities or to conceptual erosion entities that simulate local deposition and erosion of sediments the sedimentation model reproduces the various climatic periods during which the sediments were deposited by simulating genetic periods and associated modelled processes for each period the model was constrained by quantitative field data such as altitude of ancient channels and deposits or thickness of sediments the general geometry of the alluvial deposits was satisfactorily reproduced during the simulation characteristic large scale features emerge despite the use of local rules the model results are discussed with reference to other approaches such as geostatistical or boolean models and the applicability of the model to other less documented alluvial plains is outlined

joint inversion of em and magnetic data for near surface studies magnetic and electromagnetic measurements are influenced by magnetic susceptibility and thus are widely used in geophysical surveys for archeology or pedology to date the data inversion is performed separately a filtering process incorporating both types of data is presented here after testing the algorithm with synthetic data the algorithm is used in several case studies in archeological prospecting this approach presents two advantages establishing the presence of remanent magnetizations viscous or thermoremanent and achieving more refined depth analysis of the anomaly

interpretation of shallow electromagnetic instruments resistivity and magnetic susceptibility measurements using rapid 1d 3d inversion we have developed an inversion process of electromagnetic induction emi data based on a two step approach with 1d inversion of the entire studied surface and a fast 3d inversion applied over limited areas this process is similar to that formerly used in resistivity prospection for the study of soil environmental engineering or archaeological explorations low frequency electromagnetic instruments referred to as slingram emi have highly useful specificities they are light are easy to move in the field and can simultaneously measure the ground s electric conductivity and magnetic susceptibility they have thus been used to map these properties over large surface areas within relatively short periods of time and at reasonable expense the possibility of combining several coil geometries has opened up the potential for multidepth techniques and systematic 1d inversion which are found to be sufficiently revealing to allow larger portions of surveyed areas to be analyzed in the targeted areas selected for 3d inversion the geometries of the 3d features and the resistivity and or susceptibility contrasts are determined this step is based on the method of moments where only 3d heterogeneities are meshed and only a small number of major characteristics such as contrast thickness width etc are sought we first applied this process to synthetic data then to data acquired at an experimental test site and finally to field cases the rapid 3d inversion complements the 1d inversion by solving a series of issues correction for the apparent anisotropy generated by the instrument configuration multiarched anomalies precise location of lateral changes and determination of the properties contrasts our inversion results highlighted the importance of the instrument geometry we also have determined that apparent magnetic susceptibility data can be more appropriate for the determination of the volume of man made features and can be highly complementary to conductivity data

riparian wetlands of the middle reach of the seine river france historical development investigation and present hydrologic functioning a case study along the middle reach of the seine river upstream from paris riparian wetlands that have been functioning for centuries first as a result of a succession of sedimentological hydrological processes and later of continuous management practices where the value of the wetlands has been acknowledged as well as their importance for the ecology here we present the results of a multidisciplinary research programme focused on this system with emphasis on its present hydrological functioning and on the tools used to understand and quantify it the major hydrological and geochemical processes that are active at present are reviewed but past processes are also described as well as the potential long term evolution of the system this study uses several innovative tools to investigate the wetlands and analyse them in space thermographic aerial survey and electromagnetic prospecting resulting in a map of clay layer thickness concerning the wetland hydrology water budgets established at different time scales several years one year a season illustrate the exchanges between the watershed the river and the wetland and water storage in the wetlands during flood events the results show how the upstream reservoirs built during the last 20 years presently control the preservation and functioning of downstream riparian wetlands monitoring and modelling of the hydrological functioning of one wetland site have made it possible to identify and quantify exchanges between the wetland especially in the unsaturated upper layer and its environment in situ measurements of denitrification rates in the wetland were used to make initial estimates of its nitrate elimination capacity

quantification of quaternary vertical movements in the central pannonian basin a review of chronologic data along the danube river hungary abstract this study aims at a new quantification of neotectonic deformation of the central part of the pannonian basin we use terrace levels and associated travertine as well as speleothem data along the danube river to quantify its incision rate and thus estimate the amount and rate of uplift at the axis of the hungarian mountain range hmr several terrace levels and other geomorphic features along the danube river are indicative for quaternary uplift of the axial part of the emerging hungarian mountain range while the correlative terraces are at considerable height at the axis of the hmr the terraces are gradually dipping below the basin fill of the adjacent lowlands the correlation of the terrace segments is difficult because of their poor preservation small size and variable height the geomorphologic horizons indicate gradual incision of the river throughout the quaternary during simultaneous deformation however no reliable chronological data have been available so far to quantify landscape forming processes such as uplift incision or erosion rates a reconsideration of existing published data for three consecutive segments of the danube valley yields incision rates between 0 14 and 0 41 mm year for the last 360 ky with the highest value for the area of the danube bend accordingly the middle to late quaternary uplift rate of the axial zone of the hmr exceeded significantly that of the marginal areas these rates represent an approximation as some quantitative data are still controversial our results suggest that formation of the danube terraces is result of river incision triggered by the uplift of the hmr and modified by periodic climate changes

a multi methodological approach to reconstruct the configuration of a travertine fissure ridge system the case of the cukor quarry suttő gerecse hills hungary abstract travertines are continental carbonates that precipitate from spring waters mainly due to co2 degassing they are widely quarried as building stone which has led to numerous often abandoned travertine quarry outcrops these and other outcrops however merely represent the surface expressions of the complex architecture of travertine bodies and their deep rooted feeding systems integration of field observations and geochemical analyses with crucial subsurface geophysical data is required in order to fully understand travertine systems and their relationship to the local geological framework such a multi methodological approach is illustrated here for the case of the abandoned cukor quarry radio magnetotelluric rmt and electrical resistivity tomography ert surveys provide unique insights into local tectonics geobody architecture and the topography preceding travertine deposition altogether the lens shaped isolated domal geobody with spring proximal lithofacies and subvertical bedding in addition to the contrasting geochemistry and age with surrounding travertine enabled the unequivocal reconstruction of the dismantled cukor fissure ridge this study illustrates the high potential of this multi methodological approach on poorly exposed strongly weathered quarried and tectonically deformed travertine bodies and provides information on the complex feeding system beneath travertine deposits their reconstruction can be interpreted in light of the neo tectonic expression of regional uplift helps to complete the regional tectonic history and provides insights into older landscapes that lack preservation or would no longer be immediately recognized at the surface

growth of a pleistocene giant carbonate vein and nearby thermogene travertine deposits at semproniano southern tuscany italy estimate of co2 leakage abstract a giant carbonate vein 50 m thick fissure ridge travertines and nearby travertine plateaus in the semproniano area mt amiata geothermal field southern tuscany italy are investigated through a multidisciplinary approach including field and laboratory geochemical analyses u th geochronology c nd o and sr isotope systematics ree abundances and fluid inclusion microthermometry the main aim of this work is to understand 1 modes and rates for the growth of the giant vein and nearby travertine deposits within a quaternary volcano tectonic domain 2 implications in terms of the co 2 leakage and 3 possible relationships with quaternary paleoclimate and hydrological oscillations results show that the giant vein was the inner portion of a large fissure ridge travertine and grew asymmetrically and ataxially through repeated shallow fluid injections between 650 and 85 ka with growth rates in the 10 2 10 3 mm a order the giant vein developed mainly during warm humid interglacial periods partially overlapping with the growth of nearby travertine plateaus estimated values of co 2 leakage connected with the vein precipitation are between about 5 10 6 and 3 10 7 mol a 1 km 2 approximately representing one millionth of the present global co 2 leakage from volcanic areas temperature estimates obtained from o isotopes and fluid inclusion microthermometry indicate epithermal conditions 90 50 c for the circulating fluid during the giant vein growth with only slight evidence of cooling with time geochemical and isotope data document that the travertine deposits formed mainly during pleistocene warm humid periods within a tectonically controlled convective fluid circuit fed by meteoric infiltration and maintained by the regional geothermal anomaly hosted by the carbonate reservoir of the mt amiata field

stress induced late stage subsidence anomalies in the pannonian basin abstract subsidence sedimentation and tectonic quiescence of the pannonian basin was interrupted a few million years ago by tectonic reactivation this recent activity has manifested itself in uplift of the western and eastern flanks and continuing subsidence of the central part of the pannonian basin low to medium magnitude earthquakes of the carpathian pannonian region are generated mostly in the upper crust by reverse and wrench fault mechanisms there is no evidence for earthquakes of extensional origin 2 d model calculation of the subsidence history shows that a recent increase in magnitude of horizontal compressional intraplate stress can explain fairly well the observed quaternary uplift and subsidence pattern we propose that this stress increase is caused by the overall europe africa convergence in late pliocene consumption of subductible lithosphere at the eastern margin of the pannonian basin was completed and the lithosphere underlying the pannonian basin became locked in a stable continental frame consequently extensional basin formation has come to an end and compressional inversion of the pannonian basin is in progress

source properties of the 29 january 2011 ml 4 5 oroszlany hungary mainshock and its aftershocks abstract in the most seismically active region of hungary an earthquake of m l 4 5 occurred near the town of oroszlany on 29 january 2011 the mainshock was followed by more than 200 aftershocks this event is the first earthquake in the country above m l 4 that was recorded on a significant number of three component digital seismic stations according to the inversion of arrival times the hypocenter of the mainshock was at a depth of about 5 km near oroszlany with horizontal errors of about 1 5 km the aftershocks were confined to a small region next to the mainshock for the main event we obtained an average moment magnitude of m w 4 2 p and s wave source radii of r p 970 and r s 972 m and static stress drops of p 6 67 10 5 and s 17 60 10 5 pa from the analysis of p and s wave displacement spectra respectively the retrieved spectral source parameters for the investigated events agree well with the results of earlier research we have also shown that our local waveform inversion method applied in this study is suitable to estimate the earthquake source mechanism for low magnitude events using local waveforms exclusively the moment tensor computed for the mainshock from local waveform data shows a strike slip mechanism with a north south striking and an east west striking nodal plane agreeing well with regional moment tensor solutions of other agencies the source mechanisms of four aftershocks with m l 2 were also successfully estimated three of them had strike slip mechanism very similar to that of the mainshock whereas the fourth one was a thrust faulting event with some strike slip component the subhorizontal p axis struck about northeast southwest for both the mainshock and all the analyzed aftershocks coinciding with the general trend of the compressional stress field in the epicentral region

geobody architecture of continental carbonates gazda travertine quarry suttő gerecse hills hungary abstract the gazda quarry is one of the largest outcrops of the present day sutt travertine complex that is situated close to the town of sutt hungary in the pannonian basin sedimentological and petrographical analyses show that the gazda travertine body is built out of phytohermal wavy laminated massive and flat laminated travertine lithofacies representing reed mound slope lacustrine and palustrine depositional environments respectively based on petrographic analyses the following three main textural features were recognized that allow to describe the most common microscopic features 1 micrite textures 2 micritic coatings and crusts and 3 different types of clasts each major lithofacies is characterized by a particular association of these textural types the geometry of the travertine beds follows the antecedent land surface a ne sw striking pre pleistocene valley it is proposed that in this valley travertine precipitation took place along a gently sloping terrain the gazda travertine system was fed by at least two groundwater springs one of them was located ne of the quarry from which waters were flowing along the axis of the valley the other source was located to the east of the gazda quarry and waters joined the main water course along the valley closest to the confluence a phytohermal mound developed with lateral slope and eventual pond depositional systems onlapping and interfingering with the flat laminated lithofacies indicate alternating activity of the two springs fractures observed in the quarry are mainly related to postdepositional gravitational sliding however neotectonic forces resulting in nw se tension also played a role in the formation of the fractures stable oxygen and carbon isotope analyses show that water temperature was approximately 25 c petrographic studies indicate that only syn diagenetic processes affected the precipitates therefore the original stable oxygen isotope signatures characteristic of the depositional environment were preserved detailed sedimentological and geochemical study of the gazda travertine complex allowed small scale facies characterization providing information about the ancient depositional environment and the heterogeneous nature of these carbonates

investigating the penultimate and last glacial cycles of the suttő loess section hungary using luminescence dating high resolution grain size and magnetic susceptibility data the loess paleosol record at sutt provides an excellent high resolution archive of climate and environmental changes loess deposits with a thickness of 20 m cover the travertine at sutt in the northern part of hungary next to the right bank of the danube river the loess sequence is intercalated with two greyish stratified horizons three brownish steppe like soils and a pedocomplex including a reddish brown paleosol covered by a chernozem like paleosol detailed infrared stimulated luminescence irsl dating was carried out revealing more or less continuous sedimentation from marine isotope stage mis 6 mis 2 sedimentological and paleomagnetic investigations have been performed to provide a high resolution study of the sutt loess paleosol sequence in order to reconstruct the paleoclimate and environmental changes during the penultimate and last glacial cycles grain size and magnetic susceptibility ms records of the sutt profile basically show similar patterns to those of other european loess sections however small differences are traced at sutt including more intensive deposition of coarser grained materials during mis 6 4 the loess record at sutt has a transitional position within the european loess belt as its sediment was deposited under an intermediate climate between the loess successions from the southern carpathian basin which accumulated under drier climate and the loess sequences from western europe which developed under wetter climate during the middle and late pleniglacial

what do we really know about early diagenesis of non marine carbonates abstract non marine carbonate rocks including cave spring stream calcrete and lacustrine palustrine sediments are susceptible to early diagenetic processes these can profoundly alter the carbonate fabric and affect paleoclimatic proxies this review integrates recent insights into diagenesis of non marine carbonates and in particular the variety of early diagenetic processes and presents a conceptual framework to address them with ability to study at smaller and smaller scales down to nanometers one can now observe diagenesis taking place the moment initial precipitates have formed and continuing thereafter diagenesis may affect whole rocks but it typically starts in nano and micro environments the potential for diagenetic alteration depends on the reactivity of the initial precipitate commonly being metastable phases like vaterite ca oxalates hydrous mg carbonates and aragonite with regard to the ambient fluid furthermore organic compounds commonly play a crucial role in hosting these early transformations processes like neomorphism inversion and recrystallization cementation and replacement generally result in an overall coarsening of the fabric and homogenization of the wide range of complex primary microtextures if early diagenetic modifications are completed in a short time span compared to the annual to millennial time scale of interest then recorded paleoenvironmental signals and trends could still acceptably reflect original depositional conditions however even compact non marine carbonate deposits may behave locally and temporarily as open systems to crystal fluid exchange and overprinting of one or more geochemical proxies is not unexpected looking to the future relatively few studies have examined the behaviour of promising geochemical records such as clumped isotope thermometry and non conventional stable isotopes in well constrained diagenetic settings ongoing and future in vitro and in situ experimental approaches will help to investigate and detangle sequences of intermediate diagenetic products processes and controls and to quantify rates of early diagenesis bridging a gap between nanoscale molecular lab studies and the fossil field rock record of non marine carbonates

travitonics using travertines in active fault studies abstract late quaternary travertines deposited from hot springs can reveal much about the neotectonic attributes and histories of structures on the basis of field studies in the aegean region turkey and greece the northern apennines italy and the basin and range province usa we conclude that the following relationships are of predictive value i travertine deposits are preferentially located along fracture traces either immediately above extensional fissures or in the hanging walls of normal faults ii the locations of many travertine fissure ridge deposits coincide with step over zones relay ramps between fault segments networks of intersecting tensional fissures reflecting the complex strains experienced in such settings are probably responsible for enhancing hydrothermal flow iii the morphology of travertine deposits overlying extensional fissures is controlled by the rheology of the underlying materials tufa cones towers pinnacles form on former and present lake floors where fissures underlie unconsolidated sediments whereas fissure ridges develop where fissures cut bedrocks at the surface iv fissure ridges comprise outwardly dipping bedded travertine flanking a central tensional fissure filled by vertically banded travertines fissures can be used to infer local stretching directions v where there are travertines datable by the u series method it is possible to calculate time averaged dilation and lateral propagation rates for individual fissures vi most fissures cutting fissure ridges comprise self similar angular segments with fractal dimensions in the range 1 00 1 12 the properties of bedded travertine combined with stress perturbations at fissure tips probably being responsible for such similar fractal dimensions being inferred from such a wide range of locations fissures gradually increasing in width with depth are products of continuous fracture dilation in contrast to those that form during episodic dilation which display stepped increases of width with depth vii travertine deposited from springs along fault zones accumulate in terraced mounds sited down slope of the spring line viii many post depositional fractures cutting travertine deposits are locally oriented at right angles to deposit margins and ix systematic joints in travertines are restricted to those parts of eroded sheet deposits that have been exhumed

quantifying multiple electromagnetic properties in emi surveys a case study of hydromorphic soils in a volcanic context the lac du puy france we used two different loop loop electromagnetic induction emi devices to determine the 3d geometry and morphology of the pedo sedimentary filling and underlying basaltic bedrock of a former wetland in a volcanic soil area the lac du puy depression auvergne france electrical conductivity or resistivity is usually sufficient for environmental and soil science applications but the local volcanic context of the survey area results in high values of magnetic susceptibility and possible electrical polarization effects therefore we investigated the roles of the four properties electrical conductivity magnetic susceptibility magnetic viscosity and dielectric permittivity we created models using these four properties for the two coil configurations of each device in order to assess the degree to which each of the properties contributed to the recorded electromagnetic signal the results show that electrical conductivity controls the quadrature component of the secondary field response but that it can be affected by high values of magnetic viscosity while magnetic susceptibility controls the in phase component moreover the low frequencies imply a limited contribution of dielectric permittivity to the in phase component except in the cases of higher permittivity or frequency values or greater inter coil separation based on these observations we propose a way to map the apparent properties from field measurements we then carried out a 1d inversion first by considering the electrical conductivity alone and secondly by taking all the electromagnetic properties into account the results show that there is a marked contrast in the complex magnetic susceptibility between the sedimentary in fill and the border of the lac de puy depression stronger than for the electrical conductivity and that permittivity is unlikely to have a significant influence the shape and nature of the sedimentary in fill was thus considerably refined by the second inversion results based on the three other properties these data combined with litho stratigraphic observations from a previous study allowed the lateral continuity and geometry of the in fill to be assessed across the whole basin results are also consistent with previous interpretations of the depression as a pseudo sinkhole a relatively common morphology in volcanic plateaus analysis of the magnetic properties also made it possible to characterize the spatial variation of some key features related to hydromorphic processes such as clayey granularity and the development of iron oxides hydroxides this opens up the possibility for using new methods for rapid spatial and pedological characterization of hydromorphic soils and palaeosoils

temperature dependence of oxygen and clumped isotope fractionation in carbonates a study of travertines and tufas in the 6 95 c temperature range conventional carbonate water oxygen isotope thermometry and the more recently developed clumped isotope thermometer have been widely used for the reconstruction of paleotemperatures from a variety of carbonate materials in spite of a large number of studies however there are still large uncertainties in both 18o and 47 based temperature calibrations for this reason there is a need to better understand the controls on isotope fractionation especially on natural carbonates in this study we analyzed oxygen carbon and clumped isotopes of a unique set of modern calcitic and aragonitic travertines tufa and cave deposits from natural springs and wells together these samples cover a temperature range from 6 to 95 c travertine samples were collected close to the vents of the springs and from pools and tufa samples were collected from karstic creeks and a cave the majority of our vent and pool travertines and tufa samples show a carbonate water oxygen isotope fractionation comparable to the one of tremaine et al 2011 with some samples showing higher fractionations no significant difference between the calcite water and aragonite water oxygen isotope fractionation could be observed the 47 data from the travertines show a strong relationship with temperature and define the regression 47 0 044 0 005 106 t2 0 205 0 047 the ph of the parent solution mineralogy and precipitation rate do not appear to significantly affect the 47 signature of carbonates compared to the temperature effect and the analytical error the tufa samples and three biogenic calcites show an excellent fit with the travertine calibration indicating that this regression can be used for other carbonates as well this work extends the calibration range of the clumped isotope thermometer to travertine and tufa deposits in the temperature range from 6 c to 95 c

tectonic and climatic control on terrace formation coupling in situ produced 10be depth profiles and luminescence approach danube river hungary central europe abstract the terrace sequence of the hungarian part of the danube valley preserves a record of varying tectonic uplift rates along the river course and throughout several climate stages to establish the chronology of formation of these terraces two different dating methods were used on alluvial terraces exposure age dating using in situ produced cosmogenic 10 be and luminescence dating using monte carlo approach to model the denudation rate corrected exposure ages in situ produced cosmogenic 10 be samples originated from vertical depth profiles enabled the determination of both the exposure time and the denudation rate post ir irsl measurements were carried out on k feldspar samples to obtain the ages of sedimentation the highest terrace horizon remnants of the study area provided a best estimate erosion corrected minimum 10 be exposure age of 700 ka we propose that the abandonment of the highest terrace of the hungarian danube valley was triggered by the combined effect of the beginning tectonic uplift and the onset of major continental glaciations of quaternary age around mis 22 for the lower terraces it was possible to reveal close correlation with mis stages using irsl ages the new chronology enabled the distinction of tiib 90 ka mis 5b c and tiiia 140 ka mis 6 in the study area surface denudation rates were well constrained by the cosmogenic 10 be depth profiles between 5 8 m ma and 10 0 m ma for all terraces the calculated maximum incision rates of the danube relevant for the above determined 700 ka time span were increasing from west

geochemistry of quaternary travertines in the region north of rome italy structural hydrologic and paleoclimatic implications in the tyrrhenian region of central italy late quaternary fossil travertines are widespread along two major regional structures the tiber valley and the ancona anzio line the origin and transport of spring waters from which travertines precipitate are elucidated by chemical and isotopic studies of the travertines and associated thermal springs and gas vents there are consistent differences in the geochemical and isotopic signatures of thermal spring waters gas vents and present and fossil travertines between east and west of the tiber valley west of the tiber valley 13c of co2 discharged from gas vents and 13c of fossil travertines are higher than those to the east to the west the travertines have higher strontium contents and gases emitted from vents have higher 3he 4he ratios and lower n2 contents than to the east fossil travertines to the west have characteristics typical of thermogene thermal spring origin whereas those to the east have meteogene low temperature characteristics including abundant plant casts and organic impurities the regional geochemical differences in travertines and fluid compositions across the tiber valley are interpreted with a model of regional fluid flow the regional mesozoic limestone aquifer is recharged in the main axis of the apennine chain and the groundwater flows westward and is discharged at springs the travertine precipitating waters east of the tiber valley have shallower flow paths than those to the west because of the comparatively short fluid flow paths and low normal heat flow the groundwaters to the east of the tiber valley are cold and have co2 isotopic signatures indicating a significant biogenic contribution acquired from soils in the recharge area and limited deeply derived co2 in contrast spring waters west of the tiber valley have been conductively heated during transit in these high heat flow areas and have incorporated a comparatively large quantity of co2 derived from decarbonation of limestone the elevated strontium content of the thermal spring water west of the tiber valley is attributed to deep circulation and dissolution of a triassic evaporite unit that is stratigraphically beneath the mesozoic limestone u series age dates of fossil travertines indicate three main periods of travertine formation ka 220 240 120 140 and 60 70 based on the regional flow model correlating travertine deposition at thermal springs and precipitation in the recharge area we suggest that pluvial activity was enhanced during these periods our study suggests that travertines preserve a valuable record of paleofluid composition and paleoprecipitation and are thus useful for reconstructing paleohydrology and paleoclimate

applications and advantages of the slingram electromagnetic method for archaeological prospecting the electromagnetic slingram method can provide three types of information simultaneously 1 the apparent resistivity of the ground 2 its apparent susceptibility and 3 the characteristic signatures of buried metallic objects to build an apparatus with these three measurement capabilities requires an appropriate choice of parameters including frequency coil separation and coil orientation as well as calculations which take into account the electrical resistivity and the magnetic susceptibility of the ground the value of the slingram method for archaeological applications is shown by two examples 1 a gallo roman pottery workshop investigated with measurements of the apparent susceptibility using a reduced sampling wide mesh grid technique and 2 the study of a bronze hoard site located in a marsh capabilities of the slingram method may be improved by further study of an apparatus using several receivers which would increase the depth of investigation use of several frequencies would over

field and or resistivity mapping in mt vlf and implications for data processing the ratio of the horizontal electric and magnetic components of the electromagnetic field generated by a radio transmitter in the very low frequency vlf range is used in mt vlf resistivity mapping to determine the apparent resistivity of the ground a theoretical calculation of the responses of simple 2 d and 3 d prismatic bodies shows that the measurable lateral variations in both fields are independent uncoupled and correspond to frequency independent static variations it is advantageous therefore to process and map the fields separately processing methods used in gravimetry and magnetics are especially appropriate in correcting the apparent anisotropy related to the horizontal polarization of the primary field and in integrating upward continuation the high frequency spatial variations the different processes tested on a synthetic case and on data obtained at the centre de recherches geophysiques crg test site showed how to eliminate shallow features and a current channeling conductor to fa

travertines depositional morphology and the bacterially constructed constituents abstract investigation of travertine accumulations throughout central italy and the west central u s has shown that the carbonate is precipitated in response to both inorganic and organic processes individual deposits range up to 85 m thick and hundreds of square kilometers in areal extent all of the carbonate is low magnesian calcite water chemistry temperature and morphology of the accumulation greatly influence the constituents comprising these deposits harsh environmental situations favor inorganic deposits while increasingly more moderate conditions result in the formation of a greater abundance of organically precipitated material morphological variations of travertine deposits recognized include 1 waterfall or cascade 2 lake fill 3 sloping mound fan or cone 4 terraced ound and 5 fissure ridge gross morphology internal stratification and constituents comprising these deposits vary systematically depending upon the type of accumulation and chemistry of the waters bacterially precipitated calcite forms a large percentage of the carbonate in many travertine accumulations exceeding 90 of the framework grains comprising some of the lake fill deposits bacteria are among the first taxa to inhabit and reproduce in harsh spring environments and produce a variety of fascinating constituents the bacteria are primarily rods generally 0 2 m in diameter and less than 1 0 m in length the rods readily decay resulting in calcite crystals loaded with micropores the basic building block of bacterially constructed travertine is a clump of bacteria averaging 20 m in diameter enclosed in a single crystal of calcite aggregates of these crystals produce a variety of deposits including 1 crudely laminated carbonate mud 2 finely laminat d layers of mud 3 intraclasts 4 foam rock and 5 shrubs the shrubs are most striking commonly forming layers 1 3 cm thick but also producing bacterial pisoids at some locales bacterial stromatolites composed of layers of shrubs alternating with finely laminated layers of bacterial mud comprise essentially the entire deposit the shrub layers are the result of flourishing summer growth of bacteria and furthermore show remarkable daily laminae 0 1 0 5 mm thick the importance of bacteria in the formation of travertine and their universally recognized abundance in modern sediments provides an impetus for a reexamination of the role of bacteria in the origin of other types of ancient deposits

the history of soil erosion and fluvial deposits in small catchments of central europe deciphering the long term interaction between humans and the environment a review abstract during the last few decades many case studies focused on the dynamics of fluvial systems in response to hillslope erosion land use impact and climate changes this paper will review the current state of knowledge of the dynamics of past soil erosion and gullying in small catchments

paleoclimatic implications of u series dates for lake sediments and travertines in the arava rift valley israel abstract the sayif travertines and lacustrine limestones cropping out in the northern arava valley a region of extreme aridity have been dated by the 230 th 234 u disequilibrium method the consistency between the stratigraphic position and the apparent ages at each of the sampling sites strongly supports the reliability of the ages most of the ages fall within two clusters that are coincident with ages representative of oceanic oxygen isotope stages 5 and 7 the colder intervening stage 6 was not a period of substantial travertine formation during the warmer global episodes of isotopic stages 5 and 7 the arid south of israel apparently was considerably wetter than at present

uranium series chronology and environmental applications of speleothems an increasing number of scientists recognize the value of speleothems1 as often extremely well preserved archives of information about past climate vegetation hydrology sea level nuclide migration water rock interaction landscape evolution tectonics and human action well constrained data are required to document past changes reconstruct past patterns and predict future responses of the earth system at a wide range of spatial and temporal scales speleothems are particularly useful in this regard because they can be found in many locations of the globe sampled at high resolution and reliably dated using high precision uranium series techniques speleothems are bodies of mineral material formed in caves as the result of chemical precipitation from groundwater flowing or dripping in a cave most speleothems are composed of calcite formed by slow degassing of co2 from supersaturated groundwater but aragonite and gypsum forms are also common particularly near cave entrances where evaporative effects are important a host of different speleothem types decorate the walls ceilings and floors of caves and their mineralogy and morphology is a function of fluid flow and chemistry of waters feeding a particular location as well as the ambient conditions temperature chemistry light in the air or water filled void subaerial forms include the familiar stalagmites stalactites draperies flowstones subaqueous forms include rimstone pools rafts mammillary calcite wall coatings and dog tooth spar for an extensive review of the types of speleothem that have been observed see hill and forti 1997 speleothems are used in a multitude of ways to explore past environmental conditions perhaps the most fundamental of which is their very presence or absence deposition of speleothems relies on sufficient water supply and soil co2 to enable dissolution and transport of reactants in the vadose zone to underlying caves in arid or glacial times conditions may not have been favorable for speleothem formation

high sampling rate measurement and data treatment for mobile investigations kinematic electrical resistivity tomography kert abstract this paper presents an innovative system which adapts electrical resistivity tomography ert for fast investigation on long transects the device consists in a set of on the go sensors allowing high sampling rate measurement for mobile prospections the weak contact between the mobile sensors and the soil to allow fast investigations induces very noisy raw datasets kinematic electrical resistivity tomography named kert is then associated with a data treatment process a two step process reveals the information contained in the datasets the first focuses on the procedure to remove noise through the use of a low pass filter the assessment of cutoff frequency for smoothing is deduced from a fast fourier transform fft analysis thus the value is adapted to the site and the prospection the second phase consists in calibration of the kert on a conventional static ert at this point a classical static ert was used as a reference and directed on a reduced part of the kert transect the estimation of a factor of calibration xc to correct bias revealed the resistivity variations along the entire transect and in depth in the last part of the paper the validation of the investigation method and data treatment methodology is performed on a real case study a 450 m transect is investigated in 5 min mean speed about 6 km h integrating 10 depths of investigation the steps of data processing are detailed to show the final results consisting in a zonation along the transect

travertine deposition and faulting the fault related travertine fissure ridge at terme s giovanni rapolano terme italy in this paper we describe an example of travertine fissure ridge development along the trace of a normal fault with metre displacement located in the eastern margin of the neogene quaternary siena basin in the terme s giovanni area rapolano terme italy this morphotectonic feature 250 m long 30 m wide and 10 m high formed from supersaturated hot waters 39 9 c flowing from thermal springs aligned along the trace of the normal fault dissecting travertines not older than late pleistocene 24 3 ka a straight continuous fissure with a maximum width of 20 cm occurs at the top of the ridge along its crest hot fluids flow from cones mainly located at the extremities of the ridge where travertine is depositing the travertine fissure ridge shows an asymmetrical profile since it buries the fault scarp the difference in height of slopes corresponds to the vertical displacement of the normal fault fissuring of the recent travertine deposits along the strike of the crestal fissure as well as recent hydrothermal circulation lead us to believe that the terme s giovanni normal fault may be currently active on the whole the terme s giovanni fissure ridge can be defined as a travertine fault trace fissure ridge adding a helpful example for studying the relationship between faulting and travertine deposition

magnetic and geochemical characterization of andosols developed on basalts in the massif central france identification of andosols is primarily based upon the content of their colloidal constituents clay and metal humus complexes and on the determining of andic properties this needs time and cost consuming geochemical analyses our primary aim of this study is to describe the magnetic and geochemical properties of soils rich in iron oxides derived from strongly magnetic volcanic basement in this case andosols secondary aim is to explore links between magnetic and chemical parameters of andic soils with respect to genesis factors parent material age precipitation and thickness of the soil profile six pedons of andic properties developed on basaltic lavas were analyzed down to parent rock by a set of magnetic and geochemical methods magnetic data of soil and rock samples reflect the type concentration and particle size distribution of ferrimagnetic minerals geochemical data include soil reaction ph in h2o cation exchange capacity organic carbon and different forms of extractable iron and aluminum content our results suggest the following 1 magnetic measurements of low field mass specific magnetic susceptibility can be a reliable indicator for estimating andic properties and in combination with thermomagnetic curves may be suitable for discriminating between alu andic and sil andic subtypes 2 in the studied andosols strong relationships were found between a magnetic grain size parameters precipitation and exchangeable bases b concentration of ferrimagnetic particles and degree of crystallization of free iron and c parameters reflecting changes in magneto mineralogy and soil genesis parent material age soil depth

the response of a three dimensional magnetic and conductive body in shallow depth electromagnetic prospecting summary the study of the abilities of an e m apparatus for shallow depth prospecting necessitates that we analyse the experimental data through theoretical modelling a 3 d model for a magnetic and a conductivity contrast is presented here applied to the slingram type sh3 case intercoil spacing equal to 1 5 m and frequency to 8 khz it shows that this apparatus is roughly equivalent to the classical wenner 1 m array and is more sensitive than magnetic prospection to susceptibility changes occurring in the soil above 60 cm depth the 3 d model will also be very valuable for the conception of improvements in the apparatus

rapid 1d 3d inversion of shallow resistivity multipole data examples in archaeological prospection fifteen years ago the introduction of mobile multipole arrays led to substantial improvements in shallow electric prospection because it allowed information related to thevertical distribution of ground resistivity in complement to the horizontal pattern of the detected features to be extracted however to make full use of this wealth of information further progress is needed to extendthequalitativeinterpretationofdatatoamorequantitative evaluation of the explored terrain to that intent we developed a two step process in the first step a 1d electric model is fitted to the data over the full explored area and in the second step using the moment method localized 3d interpretation is applied to limited areas for which the characteristics of a given feature require closer scrutiny after a first test with synthetic data generated using the surface integral 3d modeling method this process was applied to three different archaeological sites and one test site for both handheld pole pole array systems and a multipole continuous electric profiling mechanically pulled system at the test site the characteristics of a known wall were accurately recovered at the duntzenheim site the thickness and width of the archaeological remains determined by 3d interpretation corresponded to the features observedthrough excavation at the other two sites 3d interpretation made it possible to establish that the conductive features extend across the full extent of the superficial resistive second layers

travertine distinctive depositional fabrics of carbonates from thermal spring systems the terrestrial limestones forming at the emergence of thermal springs show a variety of unusual depositional facies the specific lithological and petrological features of these deposits have few counterparts in the marine and continental karst related carbonates but they are typical of the epigean limestone that has been quarried since antiquity in the surroundings of tivoli rome under the name of travertine where it is still forming in hydro geothermal fields linked to extensional tectonics the physicochemical hydrodynamic and geological conditions specific to the tivoli thermal spring system imply hypersaturated alkaline sulphate warm to hot waters upwelling from springs fed through open fractures faults in extensional and or volcanic regimes these features together with the hydrodynamic behaviour of the water flows running from the vents control the petrogenetic features of the travertine a well bedded mostly finely laminated porous but quite compact limestone the results of a detailed comparative petrological analysis carried out on the lithofacies of travertine limestones and of those observed during formation within numerous active thermal spring fields provide the elements required for an exhaustive textural classification of the travertine lithofacies which has not yet been described systematically according to the genetic processes and fabrics the thermal deposits that originate from such hypersaturated alkaline sulphate warm to hot waters can be subdivided into abiotic crystalline crusts microbially mediated crusts microbialites and granular deposits mostly represented by small accumulations of lime mudstone some of the granular deposits and the microbialites are only partially comparable with analogous sediments forming on tidal flats sabkhas or other continental sites however the facies association of crystalline crusts and laminar curled microbialites has no counterpart in the marine realm the widespread presence of thermophile bacteria and sulphobacteria and the general absence of autochthonous eukaryote organisms unable to live in poisonous sulphate waters are also undeniable evidence of their thermal origin

earthquake impact on fissure ridge type travertine deposition the role of travertine fissure ridges in reconstructing tectonics and related earthquakes is a challenging issue of recent debate directed at delineating historical prehistorical seismic records indeed direct measurements on a travertine fissure ridge immediately after a seismic event have never been previously performed we describe the co and post seismic effects of a m 3 6 earthquake on fluid flow and travertine deposition in a geothermal area of tuscany italy direct observation allows us to demonstrate that thermal spring re activation is directly influenced by transient seismic waves therefore providing a basis for reconstructing seismic events in the past

dating of a last glacial loess sequence by relative geomagnetic palaeointensity a case study from the middle danube basin suttő hungary abstract a thorough rock and palaeomagnetic investigation of an almost 13 m thick upper pleistocene loess palaeosol sequence lpss outcropping near the village of sutt in northern hungary was conducted to obtain rock magnetic and palaeomagnetic based chronostratigraphies the results of our rock magnetic investigations indicate that the classical chinese model of magnetic enhancement showing increasing concentration dependent rock magnetic parameters in the course of pedogenesis is also valid for the northern carpathian basin we constructed a relative geomagnetic palaeointensity rpi record for the central part of the section by using the natural remanent magnetisation nrm after demagnetisation in alternating fields of 15 mt and by employing anhysteretic remanent magnetisation arm low field susceptibility k lf and saturation remanent magnetisation s irm as normalisers the three obtained rpi data sets show almost identical trends and are therefore regarded as reliable recorders of the palaeointensity of the earth s magnetic field the obtained rpi record allows for indirect dating of the lpss at sutt by correlation with the glopis and the piso stack the derived age model is in agreement with the osl based chronostratigraphy but contradicts the chronology based on the correlation between the susceptibility record and marine isotope stratigraphy mis which gives rise to the hypothesis of a possible decoupling of the palaeoclimate in the carpathian basin and the marine realm during early mis 3