modelling the lower crust by simulation of the in situ conditions an example from the saxonian erzgebirge abstract seismic data supply an image of the earth s interior with more detail than other geophysical methods however interpretation of the data is a complicated process laboratory investigations of rock properties under simulated in situ conditions can make a valuable contribution for the material interpretation of the seismic profile dekorp 3 mve 90 along the saxonian erzgebirge in germany rock samples from this area were investigated under high pressure high temperature conditions the aim of the investigations was to find relations between longitudinal and shear wave velocities v p and v s and the mineral composition of the rocks under extreme conditions of pressure and temperature the experiments with different pressure chambers were made using two types of pressure apparatus one allows numerous experiments at relatively low pressure for measurements at extreme conditions up to 2 gpa and 1000 c with partial melting a special arrangement inside a gas pressure chamber was used the experimental data are used for the construction of velocity vs depth curves together with seismic velocity models and the geological interpretation of reflections these data allow the construction of a crustal model of the erzgebirge it can be shown that there are indications of partial melting zones in the lower crust the results provide an example of the importance of this method for the material interpretation of seismic data in general

seismic velocity model of the crust and upper mantle along profile pancake across the carpathians between the pannonian basin and the east european craton abstract results are presented of a seismic wide angle reflection refraction survey along a profile between the pannonian basin pb and the east european craton eec called pancake the p and s wave velocity model derived can be divided into three sectors the pb the carpathians including the transcarpathian depression and the carpathian foredeep and the south western part of the eec including the trans european suture zone tesz seismic data support a robust model of the vp velocity structure of the crust in the pb the 22 23 km thick crust consists of a 2 5 km thick sedimentary layer vp 2 4 3 7 km s 17 20 km thick upper crystalline crust 5 9 6 3 km s and an up to 3 km thick lower crustal layer vp 6 4 km s in the central part of the carpathians a 10 24 km thick uppermost part of the crust with vp 6 0 km s may correspond to sedimentary rocks of different ages several high velocity bodies vp 5 35 5 95 and 6 05 km s within the sedimentary flysch sequences may represent volcanic sequences the moho depth changes from 25 km to 45 km over ca 100 km distance beneath the carpathians west of tesz the cratonic crust has a typical three layer structure with a pronounced thickening of the lower crust towards the ukrainian shield where a high velocity lower crust vp 7 2 km s is observed two low velocity lenses in the upper crust of the eec are interpreted beneath major sedimentary troughs lviv and volyn podolsk mantle reflectors are observed at depths of 45 km and 75 km below the pb and 10 20 km below the moho in the eec sub moho pn velocities increase from 8 0 km s beneath the pb to 8 1 km s beneath the carpathians and to 8 3 km s beneath the eec s waves of acceptable quality are recorded in the eec their signal to noise ratios increase towards the ukrainian shield

palaeozoic amalgamation of central europe new results from recent geological and geophysical investigations abstract multidisciplinary studies of geotransects across the north european plain and southern north sea and geological reexamination of the variscides of the north bohemian massif permit a new 3 d reassessment of the relationships between the principal crustal blocks abutting baltica along the trans european suture zone tesz accretion was in three stages cambrian accretion of the bruno silesian lysogory and malopolska terranes end ordovician early silurian accretion of avalonia and early carboniferous accretion of the armorican terrane assemblage ata palaeozoic plume influenced metabasite geochemistry in the bohemian massif explains the progressive rifting away of peri gondwanan crustal blocks before their accretion to baltica geophysical data faunal and provenance information from boreholes and dated small inliers and cores confirm that avalonian crust extends beyond the anglo brabant deformation belt eastwards to northwest poland the location and dip of reflectors along the tesz and beneath the north european plain suggest that avalonian crust overrode the baltica passive margin marked by a high velocity lower crustal layer on shallowly southwest dipping thrust planes forming the heligoland pomerania deformation belt the variscan orocline of southwest poland masks two junctions between the armorican terrane assemblage ata and previously accreted crustal blocks to the east is a dextrally transpressive contact with the bruno silesian and malopolska blocks accreted in the cambrian while to the north is a thrust contact with easternmost avalonia deeply buried beneath younger sedimentary cover in the northeast bohemian and rhenohercynian massifs devonian early variscide deformation dominated by wnw and nw directed thrusting records closure of ordovician devonian seaways between detached islands of the ata and avalonia

searching for regional crustal velocity density relations with the use of 2 d gravity modelling central europe case in this paper we search for a reference relation between seismic p wave velocity v and density ref for the continental crust based on the results of modern seismic experiments we compiled 2 d seismic models into a network of four each about 1100 1400 km long continental scale seismic transects cutting all main tectonic units in central europe the moho depth about 52 km beneath the tesz in se poland to about 25 km beneath the pannonian basin and the crustal structure of this area are characterised by a large variation this structural variation provides an interesting basis for gravity studies and especially for analysing the difference of the density structure between two major tectonic provinces of distinctive age difference precambrian and phanerozoic the 2 d gravity modelling applied for crustal cross sections representing the regional structure based on a unified gravity anomaly map of the area allows for a stable determination of some general features of the regional reference velocity density relation for the continental crust in general three major seismo petrological types of rocks can be distinguished sediments crystalline crust and mantle in compacted sediments the reference velocity density relation is well described by the gardner or nafe drake model calculated gravity anomalies using unified velocity density relation for the whole crystalline crust well describe observed anomalies with an average difference of 14 mgal however calculated gravity anomalies using separated velocity density relations for the crystalline crust of precambrian and phanerozoic europe describe observed anomalies better than for the entire crust with an average difference 12 mgal the most important feature of these relations is the large differentiation of the derivative d ref dv in the crystalline crust being about 0 3 g s m4 for precambrian and about 0 1 g s m4 for the phanerozoic crystalline crust the modelling suggests a very small density value in the uppermost mantle 3 11 g cm3 below the younger area while for the older area it is 3 3 g cm3

seismic basement in poland the area of contact between precambrian and phanerozoic europe in poland has complicated structure of sedimentary cover and basement the thinnest sedimentary cover in the mazury belarus anteclize is only 0 3 1 km thick increases to 7 8 km along the east european craton margin and 9 12 km in the trans european suture zone tesz the variscan domain is characterized by a 1 to 2 km thick sedimentary cover while the carpathians are characterized by very thick sediments up to c 20 km the map of the basement depth is created by combining data from geological boreholes with a set of regional seismic refraction profiles these maps do not provide data about the basement depth in the central part of the tesz and in the carpathians therefore the data set is supplemented by 32 models from deep seismic sounding profiles and a map of a high resistivity low conductivity layer from magnetotelluric soundings identified as a basement all of these data provide knowledge about the basement depth and of p wave seismic velocities of the crystalline and consolidated type of basement for the whole area of poland finally the differentiation of the basement depth and velocity is discussed with respect to geophysical fields and the tectonic division of the area

seismic anisotropy of the upper crust in southeastern poland effect of the compressional deformation at the eec margin results of celebration 2000 seismic data inversion 1 analysis of the data from celebration 2000 experiment in southeastern poland revealed azimuthal variation of the vp velocity unlikely to be caused by crustal inhomogeneity this is explained by upper crustal seismic anisotropy and was analysed by the anisotropic delay time inversion the result indicating 8 10 anisotropy fits to the geology of the area where tightly folded metapelitic rocks are abundant the fast velocity axis direction of 115 wnw ese coincides well with the azimuths of outcropping folds axes and other deformational structures in order to assess the credibility of the result synthetic tests have been performed the traveltimes calculated for isotropic models were inverted to check if an artificial anisotropy will be generated the tests indicate that realistic isotropic velocity inhomogeneities can only account for a fraction of observed traveltime variations and that the anisotropy cannot be an artifact resulting from the inhomogeneous crust

crustal and uppermost mantle s wave velocity below the east european craton in northern poland from the inversion of ambient noise records the p wave velocities vp within the east european craton in poland are well known through several seismic experiments which permitted to build a high resolution 3d model down to 60 km depth however these seismic data do not provide sufficient information about the s wave velocities vs for this reason this paper presents the values of lithospheric vs and p wave to s wave velocity ratios vp vs calculated from the ambient noise recorded during 2014 at 13 bb star seismic array 13 stations 78 midpoints located in northern poland the 3d vp model in the area of the array consists of six sedimentary layers having total thickness within 3 7 km and vp in the range 1 85 3 km s a three layer crystalline crust of total thickness 40 km and vp within 6 15 7 15 km s and the uppermost mantle where vp is about 8 25 km s the vs and vp vs values are calculated by the inversion of the surface wave dispersion curves extracted from the noise cross correlation between all the station pairs due to the strong velocity differences among the layers several modes are recognized in the 0 021 hz frequency band therefore multimodal monte carlo inversions are applied the calculated vs and vp vs values in the sedimentary cover range within 0 992 66 km s and 1 751 97 as expected in the upper crust the vs value 3 48 0 10 km s is very low compared to the starting value of 3 75 0 10 km s consequently the vp vs value is very large 1 81 0 03 to explain that the calculated values are compared with the ones for other old cratonic areas

lithospheric structure of the bohemian massif and adjacent variscan belt in central europe based on profile s01 from the sudetes 2003 experiment 1 the sudetes 2003 seismic experiment investigated the lithospheric structure of the eastern part of the variscan belt of central europe the key profile of this experiment s01 was 630 km long and extended southwestward from the margin of the east european craton across the trans european suture zone tesz and sudetes and across the bohemian massif that contains the active eger ohre rift which is an element of the european cenozoic rift system good quality first arrivals and later phases of refracted reflected p and s waves were interpreted using 2 d ray tracing techniques the derived seismic model shows large variations in the internal structure of the crust while the depth to the moho varies in the relatively narrow depth interval of 28 35 km except for the polish basin on the northeast end of the profile the sedimentary cover is thin the crystalline upper and middle crust with velocities of 5 9 6 4 km s 1 is about 20 km thick and the 7 10 km thick lower crust can be divided into three regions based on p wave velocities a low velocity region 6 5 6 6 km s 1 beneath eger rift and sudetes that is bounded on the southwest and northeast by regions of significantly higher velocity 6 8 7 1 km s 1 beneath the saxothuringian and moldanubian in the southwest and fore sudetic monocline and polish basin in the northeast high velocity bodies vp 6 5 km s 1 were delineated in the upper crust of the eger rift region the seismic structure along the s01 profile images a variscan orogenic wedge resting on the down warped margin of the plate margin containing the tesz this situation implies the northerly directed subduction of the rheic ocean that existed between the southern margin of the old red continent and the armorican terranes presently accreted into the variscan belt closure of this ocean produced the rheic suture between low velocity crust of the variscan orogenic wedge and higher velocity crust of the tesz

crustal structure below the polish basin is it composed of proximal terranes derived from baltica abstract the large scale seismic refraction and wide angle reflection experiment polonaise 97 together with lt 7 and ttz profiles carried out with the most modern techniques gave a high resolution of crustal structure of the trans european suture zone tesz in nw and central poland the results of seismic investigations show the presence of relatively low velocity rocks vp

mechanisms of decadal sea level variability in the eastern north atlantic and the mediterranean sea decadal sea level variations from tide gauge records along the western european coast and in the mediterranean sea commencing in the late 19th and early 20th centuries are examined relative to large scale atmospheric forcing recent studies have provided evidence for a link between sea level in the eastern north atlantic and atmospheric forcing however the nature of this relationship is still unclear here the outputs of a regional barotropic model and a nearly global baroclinic model are used in conjunction with wind stress and heat flux data to explore the physical mechanisms responsible for the observed sea level variability all tide gauge records show significant decadal variability up to 15 cm and are highly correlated with the nao and among themselves at decadal periods there is a coherent sea level signal that affects the eastern boundary of the north atlantic northward of 25 n and is limited to a narrow band of the order of a few hundred kilometers along the coast this band tends to become narrower towards higher latitudes we find that longshore wind and wave propagation along the boundary are the major contributors to coastal sea level variability but no significant contribution from mass redistribution linked to changes in the strength of the subtropical gyre is observed the mass component dominates sea level in the mediterranean and is mainly driven by mass exchanges with the atlantic which explains the correlation between both regions southward of 25 n sea level changes are mainly driven by heat advection through ekman fluxes

eucrust 07 a new reference model for the european crust 1 we present a new digital model eucrust 07 for the crust of western and central europe and surroundings 35n 71n 25w 35e available results of seismic reflection refraction and receiver functions studies are assembled in an integrated model at a uniform grid 15 0 15 0 the model consists of three layers sediments and two layers of the crystalline crust besides depth to the boundaries we provide average p wave velocities in the upper and lower parts of the crystalline crust the new model demonstrates large differences in the moho depth compared to previous compilations over 10 km in some specific areas e g the baltic shield furthermore the velocity structure of the crust is much more heterogeneous than in previous maps eucrust 07 offers a starting point for numerical modeling of deeper structures by allowing correction for crustal effects beforehand and to resolve trade off with mantle heterogeneities citation tesauro m m k kaban and s a p l cloetingh 2008 eucrust 07 a new reference model for the european crust geophys res lett 35 l05313 doi 10 1029 2007gl032244

3d lithosphere scale density model of the central european basin system and adjacent areas abstract to analyze the first order structural features characterizing the crust and the lithospheric mantle below the central european basin system and adjacent areas a new lithosphere scale 3d structural density model has been derived that integrates published knowledge with 3d gravity modeling with this study we aim to integrate previous results on sub domains of the study area and regional results of limited resolution in conjunction with 3d gravity analysis to derive the configuration of the lower crust and lithospheric mantle that is consistent with the known density distribution of the sediment fill and with observed deep seismic data as well as with observed gravity the derived 3d density model resolves the internal configuration of the crystalline crust below the central european basin system and adjacent areas at the regional scale and shows that the crystalline crust is characterized by a layered structure the upper to middle crystalline crust is characterized by relatively low seismic p wave velocities and densities it shows strong variations in thickness across the study area that partly correlate spatially with the inherited segmentation in response to crustal amalgamation this upper to middle crystalline crust is underlain by a continuous high density high velocity lower crustal layer locally more than 30 km thick beneath the east european craton and generally decreasing in thickness from the older to the younger tectonic domains though the thickness of this high density lower crust is generally small below the permo cenozoic central european basin system it can reach locally more than 18 km below the northeast german and the norwegian danish basins the derived depth to the lithosphere asthenosphere boundary confirms previously proposed geometries and is up to 230 km deep beneath the precambrian domain but less than 100 km deep beneath the phanerozoic domains implying that the average thermal gradient is higher in the phanerozoic lithosphere than in the precambrian part

palaeozoic terranes and their lithospheric boundaries within the trans european suture zone tesz a review the trans european suture zone tesz is a broad and complex zone of terrane accretion separating ancient lithosphere of the baltic shield and east european craton eec from the younger lithosphere of western and southern europe there is debate about the number of terranes involved and their origins the most significant terrane boundaries originally oceanic sutures are poorly exposed and are defined using faunal provinciality prominent geophysical lineaments may represent sub terrane boundaries within composite terranes the avalonia composite terrane was amalgamated to baltica in latest ician time the provenance of the malopolska and moravo silesian terranes whose neoproterozoic basement is suspect with respect to baltica but with which they nonetheless share faunal affinities is still debated the extent of the variscide rhenohercynian zone defines the southern limit of the early palaeozoic accreted terranes terranes within the bohemian massif exhibit hp metamorphism recording subduction driven collision prior to incorporation in the tesz collage itself associated with a hp event in romania the saxothuringian zone and rheic suture are directly juxtaposed with the eec and the crustal structure of the tesz has been much modified by post palaeozoic tectonism deep seismic reflection data where available show that the oceanic sutures are frequently associated with inclined reflectivity zones irz in the lithospheric mantle here inferred to mark relict subduction zones interpreting the age of subduction is complicated by offset of originally coplanar mantle and crustal segments of the irz resulting from early orogenic lithospheric delamination at the moho interface and or post orogenic reordering processes the mantle irz appear to indicate a n directed polarity for early palaeozoic subduction apparently incompatible with the geological evidence which indicates subduction of the tornquist sea beneath avalonia and a large amount of underthrusting of avalonia by baltica possible explanations for these apparently incompatible observations are evaluated

precambrian domains in lithuania evidence of terrane tectonics abstract the west lithuanian granulite wlg and east lithuanian domains eld form the proterozoic basement of lithuania and can be distinguished on the basis of differing structural patterns lithologies and evolutionary histories they are juxtaposed along the mid lithuanian suture zone mlsz in the wlg the main lithotectonic complexes comprise felsic and intermediate mostly metasedimentary granulites in the south west and mafic metaigneous granulites in the north east the former are interpreted as marine metapelites while most of the mafic ones have been derived from island arc tholeiites these rock complexes trend nw se and are marked by contrasting gravity and magnetic anomalies ne and e w striking faults and shear zones complicate the potential field patterns sets of nw trending anomalies also extend from lithuania across the baltic sea to south central sweden and indicate that the wlg complexes continue into the baltic fennoscandian shield voluminous anatectic granites alternate with the metapelites whereas the mafic granulites occur together with enderbites and charnockites in the eld the main structures produce strong nne ssw oriented gravity and magnetic anomalies which trend parallel to the belarus baltic granulite belt bbg and other terranes situated still farther east the eld is composed of metasedimentary rocks interpreted as one time graywackes shales and dolomites accumulated in continental margin arc and shallow water basinal environments amphibolites and gabbros with morb and iat characteristics and voluminous granitoids are also present the coexistence of juvenile mafic rocks with continental margin and shelf sediments suggests an oceanic back arc setting the two lithuanian basement domains display contrasting metamorphic histories that suggest separate developments before the eventual amalgamation in the wlg the metapelites indicate peak metamorphism at high temperatures up to 850 900 c and moderate pressures 8 10 kbar this was followed by cooling and reheating and then an uplift event repeated magmatic underplating accompanied the metamorphism in the eld in contrast the rocks have been subjected to comprehensive metamorphism under moderate amphibolite facies conditions that metamorphism however was not uniform throughout the metasediments in the east have recorded pressures similar to those in the neighbouring bbg 7 8 kbar but lower temperatures 650 680 c while in the central and western parts of the eld metamorphism occurred at ca 480 580 c with pressures increasing from 3 4 kbar in the centre to 6 kbar close to the western boundary reheating to 700 c due to a ca 1 5 ga magmatic event is characteristic the mlsz which separates the two lithuanian basement domains from each other is a n s oriented ca 30 50 km wide westward plunging crustal discontinuity marked by magnetic and gravity highs mafic and felsic intrusions and sheared rocks crustal thicknesses change from 42 44 km in the west to 50 km in the eastern side of the zone which also truncates a crustal low velocity layer characteristic of the wlg the amalgamation of the wlg and eld along the mlsz occurred at ca 1 71 1 66 ga after which time both domains were affected by the same post kinematic anorogenic magmatism ca 1 58 1 45 ga ago that event and related shearing were responsible for some ultimate refragmentation of the lithuanian basement terranes

crustal structure of the mid polish trough beneath the teisseyre tornquist zone seismic profile abstract a new seismic refraction and wide angle reflection experiment in the teisseyre tornquist zone ttz in poland was conducting during july 1993 as an international polish finnish german and swedish co operation the ttz profile running in an se nw direction was exactly located in the central part of the mid polish trough in the zone of maximum subsidence from upper permian to upper cretaceous 19 shot points were placed along the 450 km profile the interval between the shot points was about 25 km 31 explosions 90 to 1000 kg of dynamite were recorded in two deployments using 135 modern three component seismic stations with spacing of the recording sites of about 1 7 km in this area the depth of the consolidated basement with a velocity of about 5 7 5 8 km s is 5 to 12 km deep nevertheless the p wave velocity is very low vp

geodynamic evolution and palaeogeography of the polish carpathians and adjacent areas during neo cimmerian and preceding events latest triassic earliest cretaceous

mean sea level variability in the north sea processes and implications mean sea level msl variations across a range of time scales are examined for the north sea under the consideration of different forcing factors since the late 19th century we use multiple linear regression models which are validated for the second half of the 20th century against the output of a tide surge model to determine the barotropic response of the ocean to fluctuations in atmospheric forcing we find that local atmospheric forcing mainly initiates msl variability on time scales up to a few years with the inverted barometric effect dominating the variability along the uk and norwegian coastlines and wind controlling the msl variability in the south from belgium up to denmark on decadal time scales msl variability mainly reflects steric changes which are largely forced remotely a spatial correlation analysis of altimetry observations and gridded steric heights suggests evidence for a coherent signal extending from the norwegian shelf down to the canary islands this fits with the theory of longshore wind forcing along the eastern boundary of the north atlantic causing coastally trapped waves to propagate over thousands of kilometers along the continental slope implications of these findings are assessed with statistical monte carlo experiments it is demonstrated that the removal of known variability increases the signal to noise ratio with the result that i linear trends can be estimated more accurately ii possible accelerations as expected e g due to anthropogenic climate change can be detected much earlier such information is of crucial importance for anticipatory coastal management engineering and planning

geophysical and petrological modeling of the lower crust and uppermost mantle in the variscan and proterozoic surroundings of the trans european suture zone in central europe abstract high quality seismic data on the lower crust and uppermost lithospheric mantle in the central european part of the trans european suture zone together with thermal and gravimetric data enables the quantitative modeling of the rocks occurring in those parts of the lithosphere including their mineral compositions and the chemical composition of individual minerals the p3 seismic profile is located at the sw margin of the east european craton the lower crust is dominated by gabbronoritic intrusions plagioclase an 45 ab 55 clinopyroxene di 80 hed 20 orthopyroxene en 74 fs 26 and the uppermost mantle is harzburgitic olivine and orthopyroxene mg 0 91 the lower crust and upper mantle of the p1 seismic profile belong to the trans european suture zone albeit the upper crust is of variscan affinity the p1 lower crust has gabbronoritic composition which is layered from plagioclase rich compositions on the top to the orthopyroxene rich ones at the bottom plagioclase an 45 ab 55 clinopyroxene di 80 hed 20 orthopyroxene en 85 fs 15 and is lithologically different proterozoic and variscan surroundings the 100 200 km eclogite slice garnet alm 48 gr 25 py 27 clinopyroxene di 51 hed 10 jd 39 with a thickness of 5 10 km occurs in the uppermost mantle sampled by the p1 profile the nied wied massif is located at the ne margin of the bohemian massif which shows an exposed variscan basement the lower crust beneath the nied wied massif consists of gabbroic rock of variable proportions of plagioclase an 45 ab 55 and clinopyroxene di 80 hed 20 whereas the uppermost mantle is supposedly spinel harzburgite olivine ortho and clinopyroxene mg 0 90 our models show that the lowermost crust and uppermost mantle of the east european craton do not continue to the sw into the trans european suture zone in its central european section in poland

geophysical characteristics of the tornquist fan area northwest trans european suture zone indication of late carboniferous to early permian dextral transtension

coastal cliff top ground motions as proxies for environmental processes 1 a two year dataset of coastal cliff microseismic ground motions is used to explore energy transfer to a cliff the long term dataset enables us to characterise cliff motion responses to a wide range of environmental processes and examine whether short term characteristics are representative of the long term we examine whether cliff top motions are reliable proxies for environmental processes to inform future investigations into the drivers of erosion the study is based at an actively eroding macrotidal hard rock cliffed coast where considerable intra annual variability in wave tide and storm conditions permit the examination of a full range of environmental permutations three frequency bands of ground motion are identified that represent wind and wave processes that transfer energy to the cliff examining mean energy transfer by aggregating the frequency bands by sea water elevation reveals a notable departure from tidal inundation duration alone of relevance to understanding the timing duration and intensity of effective processes of erosion peak energy transfer to the cliff face occurs during the largest storms where water levels significantly exceed those of tidal inundation rather than at locations most frequently inundated by tides we anticipate it is therefore these conditions that are likely to be most effective in eroding hard rock coasts rather than periods which accrue energy transfer associated with still or calm waters and hence tidally modulated inundation may not relate well to coastal erosion promisingly despite signal overlap and noise cliff top motions can be used as proxies for the processes that transfer energy to the coast

lithospheric structure of the trans european suture zone along the ttz cel03 seismic transect from nw to se poland abstract the large scale celebration 2000 seismic experiment investigated the velocity structure of the crust and upper mantle between western portion of the east european craton eec and the eastern alps this area comprises the trans european suture zone the carpathian mountains the pannonian basin and the bohemian massif this experiment included 147 chemical shots recorded by 1230 seismic stations during two deployments good quality data along 16 main and a few additional profiles were recorded one of them profile cel03 was located in southeastern poland and was laid out as a prolongation of the ttz profile performed in 1993 this paper focuses on the joint interpretation of seismic data along the nw se trending ttz cel03 transect located in the central portion of the trans european suture zone first arrivals and later phases of waves reflected refracted in the crust and upper mantle were interpreted using two dimensional tomographic inversion and ray tracing techniques this modelling established a 2 d quasi 3 d p wave velocity lithospheric model four crustal units were identified along the transect from northwest to southeast thickness of the crust varies from 35 km in the pomeranian unit nw to 40 km in the kuiavian unit to 50 km in the radom ysogory unit and again to 43 km in the narol unit se the first two units are thought to be proximal terranes detached from the eec farther to the southeast and re accreted to the edge of the eec during the early palaeozoic the origin of the remaining two units is a matter of dispute they are either portions of the eec or other proximal terranes in the area of the polish basin first two units the p wave velocity is very low vp

contributions to sea level variability along the norwegian coast for 1960 2010 1 global sea level has been rising by about 20 cm during the last century and is expected to continue to rise in the 21st century the rise and variability is not spatially uniform to be able to project local changes in relative sea level rsl it is important to identify the processes that govern regional rsl variability in this study we assess the importance of different contributions to rsl variability along the coast of norway in the period 1960 2010 by using hydrographic station data at the coast sea level pressure and observed vertical land uplift we compute rsl changes due to thermal expansion haline contraction the inverted barometer effect and land uplift caused by glacial isostatic adjustment the combination of these contributions is compared to rsl variability observed with tide gauges for all but the two southernmost stations the reconstructed rsl explains 70 85 of the observed variability of the monthly sampled time series the inverted barometer effect is responsible for more than half of the explained variability while thermosteric height represents the largest contribution to the linear trend due to land uplift the local rsl rise is weaker and partly negative along the norwegian coast the residual observed minus reconstructed shows a positive trend ranging from 1 3 mm yr 1 to 2 3 mm yr 1 it is speculated that the reason for this is an increase of mass in the ocean due to melting of land based ice and to a lesser degree the combined thermohaline expansion in the deep nordic seas

evidence for a recent change in the link between the north atlantic oscillation and arctic sea ice export evidence for a recent change in the link between the north atlantic oscillation nao and arctic sea ice export through fram strait during wintertime djfm is presented from the analysis of simulated arctic sea ice and observations for the period 1958 1997 whereas no correlation between the two time series is found from 1958 to 1977 r 0 1 the correlation increased significantly thereafter r 0 7 1978 1997 the increased coherency between the nao and arctic sea ice export through fram strait during the last two decades resulted from anomalous meridional wind components near fram strait which were associated with the more easterly position of the nao s centers of interannual variability compared to 1958 1977

crustal structure along the central segment of the egt from seismic refraction studies abstract the seismic refraction line between the gulf of genova and the baltic sea was carried out in 1986 as part of the european geotraverse egt 86 the central segment of the egt also known as eugemi european geotraverse middle part has a total length of 825 km and runs from the northern margin of the alps to the baltic sea traversing mainly the variscan mountain area of western germany the p wave data of nine shotpoints were interpreted in detail and a two dimensional p velocity model of the crust was developed between the molasse basin and the southern end of the north german basin for the north german basin the data quality justifies only the construction of a simplified model the internal crustal structure is quite complex in the upper crust of the moldanubian and saxothuringian zones of the variscan orogen the velocities are lower than in the rhenohercynian area the velocity of 6 0 km s representing consolidated seismic basement is reached at depths of as much as 10 12 km northern margin of alps and north german basin and of only 3 km under the mid german crystalline rise mid crustal velocities range from 5 8 to 6 1 km s forming weak velocity reversals in some parts in the lower crust velocities as low as 6 2 km s are seen near the alps in contrast to velocities between 6 8 and 7 2 km s in the exposed variscan orogen north of shotpoint e between hannover and the river elbe the velocity of the lower crust is about 6 4 km s north of the elbe line it increases abruptly to 6 9 km s the crust mantle boundary rises from 34 km depth under the northern margin of the alps to 29 km under the swabian jura under the variscan orogen to the north the crustal thickness varies only slightly around an average depth of about 29 1 k but drops to about 30 km under the north german basin between the elbe line and the ringkobing fyn high the moho rises to a depth of about 26 km and the data indicate at least one fault like step of 1 km before the crust thickens toward the basement high the velocities in the uppermost mantle show considerable variation the highest velocity of 8 4 km s is observed beneath the saxothuringian zone and the lowest values of 7 8 7 9 km s are recorded under the hessen depression

crustal structure along the egt profile across the tornquist fan interpreted from seismic gravity and magnetic data abstract the tornquist fan is a northwestward widening splay of late carboniferous to early permian fault zones in the danish area which emanates from the teisseyre tornquist zone in the baltic sea it is located over an area of deep sedimentary basins around denmark in the southwestern corner of the former baltica plate this paper presents an integrated model of seismic velocity density and magnetic properties along the egt profile across the tornquist fan between southern sweden and northern germany the model shows distinct features that may be related to the main tectonic events in the area the caledonian crustal suture between baltica and eastern avalonia is interpreted from changes in physical parameters at all crustal levels most noticeable as an abrupt lateral change in seismic velocity in the lowest crust at moho level from 6 9 km s in baltica to only 6 4 km s in eastern avalonia thick sedimentary successions beneath the mesozoic sequence are interpreted as palaeozoic sedimentary rocks which may have been deposited on the southern margin of the baltica plate in a deep caledonian foreland basin and in late carboniferous early permian rifts and extensional basins rift related magmatism is indicated by the presence of zones of high velocity density and magnetic susceptibility as well as strong remanent magnetization thermal subsidence following the emplacement of these bodies may be the origin of regional subsidence of the danish and north german basins of late paleozoic and mesozoic age late cretaceous to early cenozoic inversion of basin structures is detected at the sorgenfrei tornquist zone stz in the transition between shield and basin areas the stz coincides with a pronounced change in crustal thickness and the southwestern edge of a major magmatic intra crustal body significant abrupt changes in moho depth exist along the profile 26 30 km beneath the deep basins ca 35 km beneath the ringkobing fyn basement high and 48 km beneath the baltic shield around the sorgenfrei tornquist inversion zone the basement in the tornquist fan area is of proterozoic age the moho topography indicates strong thinning of the crust during its phanerozoic evolution the model supports the hypothesis that existing tectonic structures and weakness zones are continuously being reactivated during subsequent tectonic activity

depth to basement for the east european craton and teisseyre tornquist zone in poland based on potential field data results of a depth to basement study are presented for the east european craton and the teisseyre tornquist zone ttz in poland the terrestrial gravity data are inverted for the top of the paleoproterozoic basement and independently for the top of the ediacaran using seismic horizons from the polandspan seismic survey and well tops as input depth measurements the depth to the ediacaran modelling was additionally extended to cover the ysogory block and northern malopolska block the results are visualised as isobath maps for the top of the paleoproterozoic basement and top of the ediacaran and an isopach map for the ediacaran supplemented with qualitative structural interpretation based on gravity and magnetic data the results of modelling show a smooth crystalline basement slope within the ttz with the top of the paleoproterozoic basement uniformly descending south westwards by 10 14 km the thickness of the ediacaran in se poland increases in the same direction to more than 10 km within the ttz such a crustal architecture in combination with the earlier documented moho elevation of 4 6 km reveals significant thinning of the paleoproterozoic crust within the ttz to form a crustal necking zone due to the ediacaran rifting a smooth geometry of the top of basement along with the lack of basement rooted faults suggests a ductile mode of crustal thinning during rifting of rodinia moreover the development of the nw se oriented rift a precursor of the tornquist ocean was associated with rifting in a ne sw direction parallel to the orsha volyn rift

seismic structure of the palaeozoic platform along polonaise 97 profile p1 in northwestern poland abstract the deep seismic profile p1 was conducted in northwestern poland as part of the polonaise 97 project data acquisition involved 100 mobile seismographs which recorded seismic waves from 11 dispersed chemical controlled explosions along this 300 km long profile a variety of seismic modelling techniques were employed to derive a velocity model along the profile this model indicates that the mesozoic and palaeozoic sediments are 6 km thick in the northwest and 3 km thick in the southeast with the main thickness variation taking place in the palaeozoic succession an undulating basement surface indicates tectonic activity during deposition of the lower palaeozoic sequence the crust is 30 33 km thick along the profile thickening gradually to the southeast the p wave seismic velocities are low 1 down to a depth of 20 km along the whole profile which we interpret as evidence for their being of sedimentary or volcanic origin the lower crust has a high p wave velocity 6 7 7 5 km s 1 high vertical velocity gradient and strong ringing reflectivity the velocity of the sub moho mantle p n is high 8 2 km s 1 features similar to the ones below this profile have been interpreted for the area south of the caledonian deformation front in northern germany and southern denmark these similarities indicate that the crust between the southeastern north sea and poland has a common origin we therefore suggest that the deep crust beneath the profile is not of variscan origin despite its location south of the variscan deformation front we propose that variscan tectonism in the area was thin skinned while the deeper crust may originate from the caledonian microcontinent east avalonia or possibly from baltica

observed mean sea level changes around the north sea coastline from 1800 to present this paper assesses historic changes in mean sea level around the coastline of the north sea one of the most densely populated coasts in the world typically such analyses have been conducted at a national level and detailed geographically wider analyses have not been undertaken for about 20 years we analyse long records up to 200 years from 30 tide gauge sites which are reasonably uniformly distributed along the coastline and 1 calculate relative sea level trends 2 examine the inter annual and decadal variations 3 estimate regional geocentric sometimes also referred to as absolute sea level rise throughout the 20th century and 4 assess the evidence for regional acceleration of sea level rise relative sea level changes are broadly consistent with known vertical land movement patterns the inter annual and decadal variability is partly coherent across the region but with some differences between the inner north sea and the english channel data sets from various sources are used to provide estimates of the geocentric sea level changes the long term geocentric mean sea level trend for the 1900 to 2011 period is estimated to be 1 5 0 1 mm yr for the entire north sea region the trend is slightly higher for the inner north sea i e 1 6 0 1 mm yr and smaller but not significantly different on the 95 confidence level for the english channel i e 1 2 0 1 mm yr the uncertainties in the estimates of vertical land movement rates are still large and the results from a broad range of approaches for determining these rates are not consistent periods of sea level rise acceleration are detected at different times throughout the last 200 years and are to some extent related to air pressure variations the recent rates of sea level rise i e over the last two to three decades are high compared to the long term average but are comparable to those which have been observed at other times in the late 19th and 20th century

transcurrent nature of the teisseyre tornquist zone in central europe results of the polcrust 01 deep reflection seismic profile teisseyre tornquist zone ttz corresponds to a crustal boundary between the precambrian east european platform eep and the palaeozoic west european platform although the zone has been controlling phanerozoic evolution of large parts of central europe its course geometry and origin are still poorly constrained deep reflection seismic profile polcrust 01 recently acquired in se poland for the first time allowed a precise comparison of the ediacaran and later tectonic patterns to the deep crustal features of the ttz and adjacent areas the ttz corresponds to the subvertical tomaszow fault separating the radom kra nik elevation composed of the typical eep crust from the bilgoraj narol block bnb in the sw with a thinned crystalline basement showing affinities to the eep crust the bnb is a part of the larger caledonian ysogory terrane as evidenced by its lower palaeozoic stratigraphy and gravity data thus for the first time the proximal baltican affinity of this unit has been documented unambiguously the ysogory terrane is delimited from the sw by the subvertical cieszanow fault zone corresponding to the holy cross suture the adjacent malopolska terrane is characterized by a distinct early palaeozoic stratigraphy and lower middle crust exhibiting sw dipping reflective packages interpreted as ne verging thrust and shear zones of a neoproterozoic orogen the observations from the polcrust 01 profile and regional comparisons indicate that the ttz is a major caledonian transcurrent zone between poland and east romania in central poland the ttz likely forms a narrow subvertical contact between the eep and a proximal kuiavia terrane as constrained by the deep refraction seismic data to the nw the zone extends towards the pomeranian part of the caledonide fold and thrust belt related to the avalonia baltica collision zone thor suture south east of poland the ttz corresponds to the rava ruska fault zone established as a caledonian suture separating adjacent terrane probably of a baltican affinity the east romanian part of the ttz conforms with the sf ntu gheorghe fault separating reworked eep crust of the pre dobrogean depression from the north dobrogea unit bearing a strong variscan and cimmerian overprint

epcrust a reference crustal model for the european plate summary we present a new crustal model for the european plate derived from collection and critical integration of information selected from the literature the model covers the whole european plate from north africa to the north pole 20 n 90 n and from the mid atlantic ridge to the urals 40 w 70 e the chosen parametrization represents the crust in three layers sediments upper crust and lower crust and describes the 3 d geometry of the interfaces and seismologically relevant parameters isotropic p and s wave velocity plus density with a resolution of 0 5 0 5 on a geographical latitude longitude grid we selected global and local models derived from geological assumptions active seismic experiments surface wave studies noise correlation receiver functions model epcrust presents significant advantages with respect to previous models it covers the whole european plate it is a complete and internally consistent model with all the parameters provided also for the sedimentary layer it is reproducible it is easy to update in the future by adding new contributions and it is available in a convenient digital format epcrust could be used to account for crustal structure in seismic wave propagation modelling at continental scale or to compute linearized crustal corrections in continental scale seismic tomography gravity studies dynamic topography and other applications that require a reliable crustal structure because of its resolution our model is not suited for local scale studies such as the computation of earthquake scenarios where more detailed knowledge of the structure is required we plan to update the model as new data will become available and possibly improve its resolution for selected areas in the future

moho topography and lower crustal wide angle reflectivity around the tesz in southern scandinavia and northeastern europe abstract the moho topography is strongly undulating in southern scandinavia and northeastern europe a map of the depth to moho shows similarities between the areas of the teisseyre tornquist zone ttz in poland and the fennoscandian border zone fbz which is partly coinciding with the sorgenfrei tornquist zone stz in denmark the moho is steeply dipping at these zones from a crustal thickness of approximately 32 km in the young palaeozoic platform and basin areas to approximately 45 km in the old precambrian platform and baltic shield the moho reflectivity pmp waveform in the polonaise 97 refraction wide angle seismic data from poland and lithuania is variable ranging from sharp to strongly reverberating signals of up to 2 s duration there is little or no lower crustal wide angle reflectivity in the thick precambrian platform whereas lower crustal reflectivity in the thin palaeozoic platform is strongly reverberating suggesting that the reflective lower crust and upper mantle is a young phenomena from stochastic reflectivity modelling we conclude that alternating high and low velocity layers with average thicknesses of 50 300 m and p wave velocity variations of 3 4 of the background velocity can explain the lower crustal reflectivity sedimentary layering affects the reflectivity of deeper layers significantly and must be considered in reflectivity studies although the reverberations from the deeper crust cannot be explained by the sedimentary layering only the reflective lower crust and upper mantle may correspond to a zone that has been intruded by mafic melts from the mantle during crustal extension and volcanism

sea level dependence on the nao over the nw european continental shelf 1 the connection between changes in the north atlantic oscillation nao and the sea level over the northwest european continental shelf is investigated for the period 1955 2000 using a two dimensional model of tides and storm surges there is a clear spatial pattern in the correlation between sea level and the nao on a winter mean timescale correlations are positive 0 8 in the northeast and negative 0 7 in the south the sensitivity of the sea level to the nao is strongest in the southern north sea up to 96 mm per unit nao index where most of the sensitivity is present also in the non hydrostatic component of sea level the relationships are validated using observed data recorded at coastal tide gauges

sea surface height variability in the north east atlantic from satellite altimetry data from 21 years of satellite altimeter measurements are used to identify and understand the major contributing components of sea surface height variability ssv on monthly time scales in the north east atlantic a number of ssv drivers is considered which are categorised into two groups local wind and sea surface temperature and remote sea level pressure and the north atlantic oscillation index a multiple linear regression model is constructed to model the ssv for a specific target area in the north sea basin cross correlations between candidate regressors potentially lead to ambiguity in the interpretation of the results we therefore use an objective hierarchical selection method based on variance inflation factors to select the optimal number of regressors for the target area and accept these into the regression model if they can be associated to ssv through a direct underlying physical forcing mechanism results show that a region of high ssv exists off the west coast of denmark and that it can be represented well with a regression model that uses local wind sea surface temperature and sea level pressure as primary regressors the regression model developed here helps to understand sea level change in the north east atlantic the methodology is generalised and easily applied to other regions

lithospheric structure beneath trans carpathian transect from precambrian platform to pannonian basin celebration 2000 seismic profile cel05 1 in 2000 a consortium of european and north american institutions completed a huge active source seismic experiment focused on central europe the central european lithospheric experiment based on refraction or celebration 2000 this experiment primarily consisted of a network of seismic refraction profiles that extended from the east european craton along and across the trans european suture zone region in poland to the bohemian massif and through the carpathians and eastern alps to the pannonian basin the longest profile cel05 1420 km is the focus of this paper the resulting two dimensional tomographic and ray tracing models show strong variations in crustal and lower lithospheric structure clear crustal thickening from the pannonian basin 24 25 km thick to the trans european suture zone region 50 km together with the configuration of the lower lithospheric reflectors suggests northward subduction of mantle underlying carpathian pannonian plate under the european plate this however conflicts with strong geological evidence for southward subduction and we present three tectonic models that are to not totally mutually exclusive to explain the lithospheric structure of the area 1 northward old subduction of the pannonian lithosphere under the east european craton in the jurassic lower cretaceous 2 a collisional zone containing a crocodile structure where carpatho pannonian upper crust is obducting over the crystalline crust of the east european craton and the carpathian pannonian mantle lithosphere is underthrusting cratonic lower crust and 3 lithosphere thinning due to the effects of neogene extension and heating with the slab associated with young subduction southward in the miocene having been either detached and or rolled back to the east in the last case the northwestward dipping in the lithosphere can be interpreted as being due to isotherms that could represent the lithosphere asthenosphere boundary in the pannonian region

crustal seismic velocity structure of southern poland preserved memory of a pre devonian terrane accretion at the east european platform margin the updated geological and potential fields data on the east european platform margin in se poland confirm the existence of several regional units differing in ediacaran to silurian development the upper silesian block malopolska block and ysogory block all the blocks are characterized by a distinct crustal structure seen in vp velocity models obtained from the seismic refraction data of the celebration 2000 programme the first two units are interpreted as exotic terranes initially derived from avalonia type crust and ultimately accreted before the late early devonian the ysogory block is probably a proximal terrane displaced dextrally along the baltica margin the sutures between the terranes do not precisely match lateral gradients in vp models this is partly explained by a limited resolution of refraction seismic data 20 km wide interpretative window most of the difference is related however to a post accretionary tectonism mainly variscan transtension transpression the latter processes took advantage of lithospheric memory recorded earlier as zones of rheological weakness along the former suture zones the course of the east european platform margin teisseyre tornquist zone corresponds most likely to the nowe miasto zawichost fault marking the ne boundary of the proximal ysogory terrane

the moho depth map of the european plate summary the european plate has a 4 5 gy long and complex tectonic history this is reflected in the present day large scale crustal structures a new digital moho depth map is compiled from more than 250 data sets of individual seismic profiles 3 d models obtained by body and surface waves receiver function results and maps of seismic and or gravity data compilations we have compiled the first digital high resolution map of the moho depth for the whole european plate extending from the mid atlantic ridge in the west to the ural mountains in the east and from the mediterranean sea in the south to the barents sea and spitsbergen in the arctic in the north in general three large domains within the european plate crust are visible the oldest archean and proterozoic crust has a thickness of 40 60 km the continental variscan and alpine crust has a thickness of 20 40 km and the youngest oceanic atlantic crust has a thickness of 10 20 km

mediterranean sea level and barotropic flow through the strait of gibraltar for the period 1958 2001 and reconstructed since 1659 sea level values from a two dimensional model of the mediterranean sea forced by atmospheric pressure and wind are used to estimate the barotropic flow through the strait of gibraltar for the period 1958 2001 the mediterranean mean sea level derived from the model ranges between 20 cm with a standard deviation of 5 5 cm and is correlated to the north atlantic oscillation nao index thus nao historical data and reconstructions are used to derive the mediterranean sea level variability from 1659 until 2001 the accuracy of the reconstruction is estimated in 2 7 cm for monthly mean values 0 41 cm for annual mean values and 0 22 cm for decadal mean values 0 48 cm for decadal winter mean sea level the barotropic flow through the strait is computed from the model output as the time derivative of the total volume of the basin during the period 1958 2001 the estimated daily flow ranges between 2 7 sv with a standard deviation of 0 56 sv the dominant periodicities are in between 1 and 2 weeks at these scales the model successfully reproduces previously published flow estimates based on current meter observations which confirms that atmospheric pressure and wind dominate the intraseasonal variability of the flow for the annual cycle the variability of the atmospherically induced flow is similar to the variability of the flow induced by the evaporation precipitation e p budget 0 025 sv though absolute values of the first are about a third of the latter at longer timescales the atmospheric contribution is much smaller than the e p induced flow

crustal structure at the easternmost termination of the variscan belt based on celebration 2000 and alp 2002 data abstract the eastern margin of the variscan belt in europe comprises plate boundaries between continental blocks and terranes formed during different tectonic events the crustal structure of that complicated area was studied using the data of the international refraction experiments celebration 2000 and alp 2002 the seismic data were acquired along sw ne oriented refraction and wide angle reflection profiles cel10 and alp04 starting in the eastern alps passing through the moravo silesian zone of the bohemian massif and the fore sudetic monocline and terminating in the tesz in poland the data were interpreted by seismic tomographic inversion and by 2 d trial and error forward modelling of the p waves velocity models determine different types of the crust mantle transition reflecting variable crustal thickness and delimiting contacts of tectonic units in depth in the alpine area few km thick lvz with the vp of 5 1 km s 1 dipping to the sw and outcropping at the surface represents the molasse and helvetic flysch sediments overthrust by the northern calcareous alps with higher velocities in the bohemian massif lower velocities in the range of 5 0 5 6 km s 1 down to a depth of 5 km might represent the se termination of the elbe fault zone the fore sudetic monocline and the tesz are covered by sediments with the velocities in the range of 3 6 5 5 km s 1 to the maximum depth of 15 km beneath the mid polish trough the moho in the eastern alps is dipping to the sw reaching the depth of 43 45 km the lower crust at the eastern margin of the bohemian massif is characterized by elevated velocities and high vp gradient which seems to be a characteristic feature of the moravo silesian slightly different properties in the moravian and silesian units might be attributed to varying distances of the profile from the moldanubian thrust front as well as a different type of contact of the brunia with the moldanubian and its northern root sector the moho beneath the fore sudetic monocline is the most pronounced and is interpreted as the first order discontinuity at a depth of 30 km

homogenization of earthquake catalog for northeast india and adjoining region a catalog for northeast india and the adjoining region for the period 1897 2009 with 4 497 earthquakes events is compiled for homogenization to moment magnitude m w gcmt in the magnitude range 3 8 7 relations for conversion of m b and m s magnitudes to m w gcmt are derived using three different methods namely linear standard regression inverted standard regression isr and orthogonal standard regression osr for different magnitude ranges based on events data for the catalog period 1976 2006 the osr relations for m s to m w gcmt conversion derived in this paper have significantly lower errors in regression parameters compared to the relations reported in other studies since the number of events with magnitude 7 for this region is scanty we therefore considered whole india region to obtain the regression relationships between m w gcmt and m s isc a relationship between m w gcmt and m w neic is also obtained based on 17 events for the range 5 2 magnitude 6 6 a unified homogeneous catalog prepared using the conversion relations derived in this paper can serve as a reference catalog for seismic hazard assessment studies in northeast india and the adjoining region

high resolution 3d seismic model of the crustal and uppermost mantle structure in poland abstract in the area of poland a contact between the precambrian and phanerozoic europe and the carpathians has a complicated structure and a complex p wave velocity of the sedimentary cover crystalline crust moho depth and the uppermost mantle the geometry of the uppermost several kilometers of sediments is relatively well recognized from over 100 000 boreholes the vertical seismic profiling vsp from 1188 boreholes provided detailed velocity data for regional tectonic units and for stratigraphic successions from permian to the tertiary and quaternary deposits these data however do not provide information about the velocity and basement depth in the central part of the trans european suture zone tesz and in the carpathians so the data set is supplemented by 2d velocity models from 32 deep seismic sounding refraction profiles which also provide information about the crust and uppermost mantle together with the results of other methods vertical seismic profiling magnetotelluric allow for the creation of a detailed high resolution 3d model for the entire earth s crust and the uppermost mantle down to a depth of 60 km the thinnest sedimentary cover in the mazury belarus anteclise is only 0 3 to 1 km thick which increases to 7 to 8 km along the east european craton eec margin and 9 to 12 km in the tesz the variscan domain is characterized by a 1 4 km thick sedimentary cover while the carpathians are characterized by very thick sedimentary layers up to about 20 km the crystalline crust is differentiated and has a layered structure the crust beneath the west european platform wep variscan domain is characterized by p wave velocities of 5 8 6 6 km s the upper and middle crusts beneath the eec are characterized by velocities of 6 1 6 6 km s and are underlain by a high velocity lower crust with a velocity of about 7 km s a general decrease in velocity is observed from the older to the younger tectonic domains the tesz is associated with a steep dip in the moho depth from 30 35 km in the paleozoic platform to 42 52 km in the precambrian craton the new model confirms the moho depth derived from previous compilations in the tesz the lower crust has a very high seismic velocity 7 0 km s which correlates to the high p wave velocity about 8 4 km s in the uppermost mantle beneath the polish basin the cratonic area is generally characterized by high p wave velocities 8 2 km s while the phanerozoic area is characterized by velocities of 8 0 km s in the tesz very high velocities of 8 3 8 4 km s are observed and the southwestern limitation of this area coincides with a high velocity lower crust and could be continued to the nw toward the elbe line the influence of the structure for teleseismic tomography time residuals of seismic waves traveling through the 3d seismic model was analyzed lithological candidates for the crust and uppermost mantle of the eec and wep were suggested by comparison to laboratory data the presented 3d seismic model may make more reliable studies on global dynamics and geotectonic correlations particularly for sedimentary basins in the polish lowlands the napped flysch sediment series in the carpathians the basement shape the southwestern edge of the eec a high velocity lower crust and the high velocity uppermost mantle in the tesz finally the new 3d velocity model of the crust shows a heterogeneous structure and offers a starting point for the numerical modeling of deeper structures by allowing for a correction of the crustal effects in studies of the mantle heterogeneities

blockage of regional seismic waves by the teisseyre tornquist zone summary during the group of scientific experts technical test gsett second experiment 22 april 2 june 1991 several hundred seismic events were located in europe associating these events with the detecting stations altogether 28 european stations including seven arrays participated in the gsett 2 experiment clearly shows that the teisseyre tornquist zone ttz influences the propagation of regional seismic phases large explosions in the bay of gdansk for example were observed by the wellestablished scandinavian arrays norsar a 830 km and arcess a z 1650 km but not by the polish station ksp a 470km nor by the new highly sensitive geress array a 750 km both situated south west of the ttz for events in central europe with comparable magnitudes we observe a similar increase of the detection threshold at stations located north east of the ttz in scandinavia to explain these observations the wave propagation of pn and pg perpendicular to the ttz was modelled for a profile from the estonian russian border region to geress with gaussian beam seismograms published crustal and uppermost mantle models for poland and for europe were used as a starting point for developing a model of the ttz the observations cannot be explained only by a graben like crustal structure with a jump in moho depth from 30 km to 50 km to defocus the seismic energy the ttz as a structural anomaly between eastern and western europe must reach down into the upper mantle to a depth of at least about 200 km the proposed model has such a deep reaching root of the ttz

integrated seismic model of the crust and upper mantle of the trans european suture zone between the precambrian craton and phanerozoic terranes in central europe abstract the structure and evolution of the trans european suture zone tesz contact between precambrian europe to the northeast and phanerozoic terranes to the southwest is one of the main tectonic questions in europe the knowledge of the crustal structure lithosphere asthenosphere boundary and mantle transition zone between two seismic discontinuities at depths 410 and 660 km is one of the most important issues to understand the earth s dynamics to create a mantle model of the tesz and surroundings we used different seismic data collected along the 950 km long polonaise 97 profile p4 previous results of 2 d ray tracing and p wave travel time modelling and new results of p wave travel time residuals methods and receiver function sections provide facts about the seismic structure from the surface down to 900 km depth in the tesz a large basin about 125 km wide is filled with sedimentary strata vp 7 0 km s 1 along most of the p4 profile however lower values to the southwest may indicate the termination of baltica high velocity 8 35 km s 1 uppermost mantle lies beneath the avalonia variscan terranes and may be due to rifting and or subduction the seismic lithosphere thickness for the eec is about 200 km while it is only 90 km in the palaeozoic platform pp the mantle transition zone is shallower and about 30 km thicker under the eec which could be due to thermal conditions lower temperature and or the presence of water and feo the result of this paper is a new compiled and integrated seismic velocity model available in digital form down to 900 km depth http www igf fuw edu pl p4 mantle which can be used as a preliminary model of the crust and upper mantle in the tesz area in central europe

crustal structure of the trans european suture zone region along polonaise 97 seismic profile p4 1 the large scale polonaise 97 seismic experiment investigated the velocity structure of the crust and upper mantle in the trans european suture zone tesz region between the precambrian east european craton eec and paleozoic platform that comprises terranes added during the caledonian and variscan orogenies 530 370 and 370 225 ma respectively this experiment included 64 shots recorded by 613 seismic stations during two deployments very good quality data were recorded along five profiles and the longest and most important one p4 is the focus of this paper clear first arrivals and later phases of waves reflected refracted in the crust and moho were interpreted using two dimensional 2 d tomographic inversion and ray tracing techniques the crustal thickness along the profile varies from 30 35 km in the paleozoic platform area to 40 km below and due northeast of the tesz to 43 km in the polish part of the eec and to 50 km in lithuania the paleozoic platform and eec are divided by the polish basin so the upper crustal structure varies considerably in the area of the polish basin the p wave velocity is very low vp 6 1 km s down to depths of 15 20 km indicating that a very thick sedimentary sequence is present we suggest two possible tectonic interpretations of the velocity models 1 baltica indented avalonia obducting its upper crust and underthrusting its lower crust in a tectonic flake structure and 2 a rifted margin of baltica underlies the polish basin this model is similar to other interpretations of seismic profiles recorded in the baltic sea the second model implies that the paleozoic platform solely consists of avalonian lithosphere and the eec of baltica lithosphere it offers a simple explanation of the difference in crustal thickness of the two platforms it also implies that the caledonian and variscan orogenies in this area were relatively soft collisions that left this continental margin largely intact

polonaise 97 an international seismic experiment between precambrian and variscan europe in poland abstract the trans european suture zone tesz comprises a series of sutures that developed by palaeozoic amalgamation of the phanerozoic central europe onto the proterozoic baltica and east european plate during the formation of pangea within tesz the permian basin in poland forms the easternmost part of the permian central european basin which is bordered on the east by the east european craton eec and on the southwest by the bohemian massif the axis of the basin the mid polish trough parallels the edge of the eec the teisseyre tornquist zone ttz is a geological inversion zone in the polish trough a large seismic experiment the polonaise 97 project was conducted in poland during may of 1997 and targeted the deep structure of the tesz and the complex series of upper crustal features associated with it it included contributions from the geophysical communities in poland denmark the usa lithuania germany finland sweden and canada this large lithospheric seismic experiment deployed 613 instruments to record 64 shots along five profiles with a total length of about 2000 km moreover five multichannel seismic reflection stations 90 and 120 channels recorded all signals from shots two dimensional velocity models were derived by p wave tomographic inversion these models provide an initial interpretation of this massive data set and allow us to present a few significant seismic and tectonic observations one of the most important is a very distinct asymmetry between the maximum thickness of the sedimentary cover in the polish trough 16 20 km and the crustal root 50 km associated with tesz ttz

thermal properties of the crust and the lithosphere asthenosphere boundary in the area of poland from the heat flow variability and seismic data high resolution 3d seismic p wave velocity model of poland grad et al tectonophysics 666 188 210 2016 and corrected for paleoclimate heat flow map majorowicz and wybraniec int j earth sci 100 4 881 887 2011 gridded to a common mesh are used together with four independent thermal models of the crust and upper mantle to calculate heat flow variation with depth and geotherms heat flow at moho depth are calculated and mapped and both confirm large variability with an elevated mantle heat flow circa 30 40 mw m2 in the paleozoic platform which is some 10 20 mw m2 higher than moho heat flow in the north eastern and south eastern poland which belong to a variety of tectonic terranes the oldest precambrian craton younger cadomian trans european suture zone carpathians temperatures calculated for the crust show consistent pattern higher temperatures beneath the paleozoic platform and lower temperatures beneath the precambrian and cadomian units at 10 km depth this difference is about 150 c about 300 c at 20 km depth and about 400 c at 50 60 km assuming the calculated isotherm 580 c as curie temperature the magnetic crust thickness was determined as 5 10 km only beneath the polish basin circa 20 km in carpathians circa 30 km in sudetes and 35 40 km beneath the precambrian and cadomian units such a thick magnetic crust results from a great depth of curie temperature thick crystalline crust and thin sediments mantle heat flow variability is mainly correlating with measured surface heat flow and influences geotherms calculated thermal lab depth follows patterns of heat flow and moho heat flow variability through poland with thinnest lithosphere in the high surface heat flow and high mantle heat flow areas comparison of this thermal lab depth estimates with seismic data based lab depth shows general coincidences when precambrian craton vs paleozoic platform are considered along the p4 seismic experiment data model circa 190 km depth vs some 90 km depth respectively however significant differences exist in many areas and especially for the se poland when compared with map for the whole of poland compiled from other seismic reported data

p and s wave velocity model of the southwestern margin of the precambrian east european craton polonaise 97 profile p3 the large scale seismic experiment polonaise 97 investigated the seismic structure of the crust and the uppermost mantle in the polish region of the trans european suture zone this paper covers the interpretation of seismic data along the 300 km long p3 profile which is located in the precambrian east european craton eec parallel to the teisseyre tornquist zone the recordings were of high quality with seismic energy detectable out to 300 km ovsets the crustal model developed by two dimensional raytracing forward modelling and waveform analysis is characterized by a subhorizontal uniform structure although the boundaries of several large basement features are crossed the crystalline crust consists of three parts the upper middle and lower crust with p wave velocities of 6 1 6 4 km s 6 55 6 7 km s and 7 05 7 15 km s respectively the p m p wave can usually be correlated at distances beginning at about 100 km but it has variable reflection character moho depth increases from 38 km at the nw end of the profile to 44 km at the se end the p n velocity of 8 05 8 1 km s is less than that previously found in neighbouring areas of the eec the v p v s ratio was determined separately for the upper middle and lower crust to be 1 67 and 1 77 respectively following the p n wave another phase with an apparent velocity of about 8 3 km si s interpreted as a weak reflection from a low contrast discontinuity in the uppermost mantle 1999 elsevier science b v all rights reserved

sea level changes in iceland and the influence of the north atlantic oscillation during the last half millennium abstract we present a new diatom based sea level reconstruction for iceland spanning the last 500 years and investigate the possible mechanisms driving the sea level changes a sea level reconstruction from near the icelandic low pressure system is important as it can improve understanding of ocean atmosphere forcing on north atlantic sea level variability over multi decadal to centennial timescales our reconstruction is from vi arholmi salt marsh in snaefellsnes in western iceland a site from where we previously obtained a 2000 yr record based upon less precise sea level indicators salt marsh foraminifera the 20th century part of our record is corroborated by tide gauge data from reykjavik overall the new reconstruction shows ca 0 6 m rise of relative sea level during the last four centuries of which ca 0 2 m occurred during the 20th century low amplitude and high frequency sea level variability is super imposed on the pre industrial long term rising trend of 0 65 m per 1000 years most of the relative sea level rise occurred in three distinct periods ad 1620 1650 ad 1780 1850 and ad 1950 2000 with maximum rates of 3 2 mm yr during the latter two of these periods maximum rates were achieved at the end of large shifts from negative to positive of the winter north atlantic oscillation nao index as reconstructed from proxy data instrumental data demonstrate that a strong and sustained positive nao a deep icelandic low generates setup on the west coast of iceland resulting in rising sea levels there is no strong evidence that the periods of rapid sea level rise were caused by ocean mass changes glacial isostatic adjustment or regional steric change we suggest that wind forcing plays an important role in causing regional scale coastal sea level variability in the north atlantic not only on multi annual timescales but also on multi decadal to centennial timescales

improved and extended tide gauge records for the british isles leading to more consistent estimates of sea level rise and acceleration since 1958 abstract this paper describes methods of obtaining improved estimates of long term sea level trends for the british isles this is achieved by lengthening the sea level records where possible then removing known sources of variability and then further adjusting for datum errors that are revealed by the previous processes after verification using metadata from archived sources local sea level variability is accounted for using a tide and surge model far field variability is accounted for using a common mode this combination reduces the residual variability seen at tide gauges around the coast of the british isles to the point that a number of previously unrecognised steps in individual records become apparent permitting a higher level of quality control to be applied a comprehensive data archaeology exercise was carried out which showed that these step like errors are mostly coincident with recorded site specific changes in instrumentation and that in many cases the periodic tide gauge calibration records can be used to quantify these steps a smaller number of steps are confirmed by buddy checking against neighbouring tide gauges after accounting for the observed steps using levelling information where possible and an empirical fit otherwise the records become significantly more consistent the steps are not found to make a large difference to the trend and acceleration observed in uk sea level overall but their correction results in much more consistent estimates of first order sea level rise and second order sea level acceleration trends over this 60 year period we find a mean rate of sea level rise of 2 39 0 27 mm yr 1 and an acceleration of 0 058 0 030 mm yr 2 between jan 1958 and dec 2018 the cleaner dataset also permits us to show more clearly that the variability other than that derived from local meteorology is indeed consistent around the uk and relates to sea level changes along the eastern boundary of the north atlantic

2 d seismic tomographic and ray tracing modelling of the crustal structure across the sudetes mountains basing on sudetes 2003 experiment data the seismic data obtained during sudetes 2003 experiment are analysed and detailed crustal structure for profiles s02 s03 and s06 is presented using three different 2 d techniques 1 smooth tomography of refracted waves travel times 2 ray tracing of reflected and refracted waves and 3 joint velocity and depth of reflector tomographic inversion in spite of different interpretation techniques used the models of the crustal structure show common characteristic features the low velocity vp 4 km s sedimentary layer was documented in the northeastern part of the study area the topmost basement has in general a velocity of 5 8 6 0 km s and velocities at ca 20 km depth are 6 15 6 25 km s the strong reflecting boundaries were found at 20 23 and 25 28 km depth with a velocity contrast about 0 4 km s and the highest velocities in the lowermost crust are 6 8 7 2 km s in general the crust of the bohemian massif is slightly thicker 33 35 km than in the northern part of the area velocities beneath moho are relatively low of 7 95 km s on the basis of well recorded reflected waves mantle reflectors were discovered in the depth interval ca 40 70 km apart of new results for the geology and tectonics of the area some conclusion could be made about different techniques used in the 2 d case the clasical ray tracing method with using all correlated phases gives the most adequate model of the structure because of full manual control of the model creation the smooth first arrival travel times tomography although very fast is not satisfactory enough to describe the complex structure so the best candidate in 3 d case seems to be travel time tomography for both refracted and reflected waves in multi layers models

seismic and geological structure of the crust in the transition from baltica to palaeozoic europe in se poland celebration 2000 experiment profile cel02 abstract the celebration 2000 together with the earlier polonaise 97 deep seismic sounding experiments was aimed at the recognition of crustal structure in the border zone between the precambrian east european craton baltica and palaeozoic europe the cel02 profile of the celebration family is a 400 km long sw ne transect running in poland from the upper silesia block usb across the malopolska block mb and the trans european suture zone tesz to the east european craton eec the structure along cel02 was interpreted using both 2d tomography and forward ray tracing techniques as well as 2d gravity modelling the crustal thickness along cel02 varies from 32 35 km in the usb to 45 47 km beneath the tesz and the eec the usb is a clearly distinctive crustal block with the characteristic high velocity lower crust 7 1 7 2 km s interpreted as a fragment of gondwana the krakow lubliniec fault is a terrane boundary produced by soft docking of the usb with the mb the malopolska crust fundamentally differs from the usb and has a strong connection with baltica it is a transitional 150 to 200 km wide unit composed of the extended baltican lower crust and the overlying low velocity 5 15 5 9 km s neoproterozoic metasediments in the up to 18 km thick upper crust the ysogory unit has its crustal structure identical with that of malopolska thus it is connected with baltica and cannot be interpreted as a gondwana derived terrane higher velocity and density bodies found below the mazovia lublin graben at a depth of 12 km and at the base of the lower crust might be a result of mantle derived mafic intrusions accompanying the extension of baltica by the preliminary 2d gravity modelling we have reconfirmed the need for considering the increased tesz mantle density in comparison to the eec and usb mantle

the southern margin of the east european craton new results from seismic sounding and potential fields between the north sea and poland abstract the extension of eastern avalonia from britain through the ne german basin into poland is in some sense a virtual structure it is covered almost everywhere by late paleozoic and younger sediments evidence for this terrane is only gathered from geophysical data and age information derived from magmatic rocks during the last two decades much geophysical and geological information has been gathered since the european geotraverse egt which was followed by the babel lt 7 mona lisa dekorp basin 96 and polonaise 97 deep seismic experiments based on seismic lines a remarkable feature has been observed between the north sea and poland north of the elbe line el the lower crust is characterised by high velocities 6 8 7 0 km s a feature which seems to be characteristic for at least a major part of eastern avalonia far eastern avalonia in addition the seismic lines indicate that a wedge of the east european craton eec or baltica continues to the south below the southern permian basin spb a structure which resembles a passive continental margin the observed pattern may either indicate an extension of the baltic crust much farther south than earlier expected or oceanic crust of the tornquist sea trapped during the caledonian collision in either case the data require a reinterpretation of the docking mechanism of eastern avalonia and the elbe odra line eol as well as the elbe fault system together with the intra sudedic faults appear to be related to major changes in the deeper crustal structures separating the east european crust from the paleozoic agglomeration of middle european terranes

crustal structure across the tesz along polonaise 97 seismic profile p2 in nw poland abstract the polonaise 97 po lish l ithospheric on set a n i nternational s eismic e xperiment 1997 seismic experiment in poland targeted the deep structure of the trans european suture zone tesz and the complex series of upper crustal features around the polish basin one of the seismic profiles was the 300 km long profile p2 in northwestern poland across the tesz results of 2d modelling show that the crustal thickness varies considerably along the profile 29 km below the palaeozoic platform 35 47 km at the crustal keel at the teisseyre tornquist zone ttz slightly displaced to the northeast of the geologic inversion zone and 42 km below the precambrian craton in the polish basin and further to the south the depth down to the consolidated basement is 6 14 km as characterised by a velocity of 5 8 5 9 km s the low basement velocities less than 6 0 km s extend to a depth of 16 22 km in the middle crust with a thickness of ca 4 14 km the velocity changes from 6 2 km s in the southwestern to 6 8 km s in the northeastern parts of the profile the lower crust also differs between the southwestern and northeastern parts of the profile from 8 km thickness with a velocity of 6 8 7 0 km s at a depth of 22 km to ca 12 km thickness with a velocity of 7 0 7 2 km s at a depth of 30 km in the lowermost crust a body with a velocity of 7 20 7 25 km s was found above moho at a depth of 33 45 km in the central part of the profile sub moho velocities are 8 2 8 3 km s beneath the palaeozoic platform and ttz and about 8 1 km s beneath the precambrian platform seismic reflectors in the upper mantle were interpreted at 45 km depth beneath the palaeozoic platform and 55 km depth beneath the ttz the polish basin is an up to 14 km thick asymmetric graben feature the basement beneath the palaeozoic platform in the southwest is similar to other areas that were subject to caledonian deformation avalonia such that the variscan basement has only been imaged at a shallow depth along the profile at northeastern end of the profile the velocity structure is comparable to the crustal structure found in other portions of the east european craton eec the crustal keel may be related to the geologic inversion processes or to magmatic underplating during the carboniferous permian extension and volcanic activity

deep seismic expression of an ancient plate boundary in europe seismological results on the structure of the upper mantle below europe reveal a marked contrast in seismic properties between precambrian and younger parts of europe the precambrian craton in eastern europe is characterized by high shear wave velocities which can be explained by low temperatures the transition to low seismic velocities below phanerozoic europe coincides with the crustal boundary zone of the craton and exists to depths of at least 140 kilometers despite the long and complex tectonic history of the plate boundary zone the transition is remarkably sharp which rules out any significant lateral transport of asthenospheric material across the suture zone

crustal and upper mantle structure of the western carpathians from celebration 2000 profiles cel01 and cel04 seismic models and geological implications summary celebration 2000 was a large international experiment that focused on the lithospheric structure in central europe it consisted of several wide angle reflection and refraction seismic profiles profiles cel01 and cel04 are located in the transition from the precambrian and palaeozoic platforms to the carpathian orogen the data were modelled using 2 d tomographic and forward modelling techniques the profile cel01 about 900 km long extends from the southwestern margin of the east european craton to the pannonian basin system the depth of moho boundary varies along the profile from 27 33 km under the pannonian basin system area 30 39 under the carpathians and within the tesz to 40 45 km under the east european craton the cel04 profile 630 km long starts in the polish trough pt and reaches the pannonian basin system along the cel04 profile the moho interface shallows from 40 km beneath the pt to about 35 km in the maopolska unit the crustal thickness is 43 km beneath the carpathians and 25 km beneath the pannonian basin system the results obtained are consistent with a commonly accepted view of the carpathians thought to be formed largely due to the interplay between palaeogene to middle miocene subduction of oceanic or suboceanic crust and subsequent collision a feature that we interpret as the subduction related orogenic root is at least partially preserved in both profiles and is manifested by a crustal thicknesses of 39

lithosphere thickness from new heat flow data of the odra variscan area s w poland equilibrium temperature data from shafts in a mining area of sw poland in the paleozoic platform were used for heat flow calculations a new technique to calculate paleoclimatic correction for heat flow determination from single deep temperature data and equilibrium surface temperatures was applied elevated surface heat flow of 82 87 mw m 2 and mantle heat flow of some 37 41 mw m 2 were found this high heat flow zone spreads from s w poland in the variscan deformation front towards the german part of the polish german basin calculations of geotherms for a variety of heat production models of the crust and upper mantle point to lithosphere asthenosphere boundary depths of about 80 90 km compared to seismologically determined depths of 90 120 km

deep structure of the earth s crust in the contact zone of the palaeozoic and precambrian platforms in poland tornquist teisseyre zone abstract one of the major tectonic problems in europe concerns the southwest margin of the east european platform in the region of the so called polish danish trough in general this margin is assumed to be the tornquist teisseyre t t line running approximately from northwest to southeast in this part of europe determination of deep crustal structure of the contact zone between the precambrian platform and the palaeozoic platform was the main aim of the deep seismic sounding dss programme in poland in 1965 1982 deep seismic soundings of the earth s crust have been made in the t t line zone along nine profiles with a total length of about 2600 km the results of deep seismic soundings have shown that the crust in the marginal zone of the east european platform has highly anomalous properties the width of this zone ranges from 50 km in northwest poland to about 90 km in southeast poland the crustal thickness of the palaeozoic platform in poland is 30 35 km and of the precambrian platform 42 47 km while in the t t tectonic zone it varies from 50 to 55 km above the moho boundary in the t t zone at a depth of 40 45 km there is a seismic discontinuity with p wave velocities of 7 5 7 7 km s boundary velocities mean velocities and stratification of the earth s crust vary distinctly along the t t zone there are also observed high gravimetric and magnetic anomalies in the t t zone the t t tectonic zone determined in this manner is a deep tectonic trough with rift properties the deep fractures delineating the t t tectonic zone are of fundamental importance for the localization of the plate edge of the precambrian platform of eastern europe in the light of dss results the northeastern margin of the t t tectonic zone is a former plate boundary of the east european platform

oceanic influence on the north atlantic oscillation and associated northern hemisphere climate variations 1959 1993 the north atlantic oscillation nao ex hibits variations at interannual to multidecadal time scales and is associated with climate variations over eastern north america the north atlantic europe and north africa therefore it is very important to understand causes of these nao variations and assess their predictability it has been hypothesized based on observations that sea surface temperature sst and sea ice variations in the north atlantic ocean influ ence the nao we describe results of an ensemble of sixteen experiments with an atmospheric general cir culation model in which we used observed sst and sea ice boundary conditions globally during 1949 1993 we show that multiyear nao and associated climate variations can be simulated reasonably accurately if re sults from a large number of experiments are averaged we also show that the ambiguous results of previous nao modeling studies were strongly influenced by the ensemble size which was much smaller than that in the present study the implications of these results for understanding and predictability of the nao are dis cussed