environmental impact assessment of the 2011 tohoku oki tsunami on the sendai plain abstract large areas of farmland in the sendai plain japan were inundated by the 11 march 2011 tohoku oki tsunami and covered by a discontinuous 30 0 2 cm thick sediment layer consisting of sand and or mud and generally thinning and fining inland two months after the tsunami numerous rice paddy fields and depressions remained ponded with brackish or saline water a series of field surveys in may august and october 2011 were carried out north of sendai airport in order to assess the environmental impact of the tsunami while evaporation had resulted in elevated conductivity in ponded water in may up to 68 2 ms cm 1 rainfall over the next five months led to dilution although brackish water was still recorded in depressions and on paddy fields tsunami sediments underlying soil and soil beyond the tsunami inundation limit were collected at 43 sites along and near a transect extending over 5 km inland and analysed for grain size organic content water leachable ions acid leachable metals and exchangeable metalloids water leachable anion and cation concentrations were elevated in sandy and muddy tsunami deposits and soils particularly in areas where seawater had stagnated for a longer period of time after the tsunami with up to 10 5 cl 6 6 na 2 8 so 4 440 mg kg 1 br measured in surface sediments the impact of saltwater inundation was documented in the chemistry of soils underlying tsunami sediments which were affected by salt contamination down to 15 cm depth and soils not covered by tsunami deposits the latter implies that the extent of tsunami inundation may successfully be determined using geochemical markers in absence of any sedimentological evidence water leachable ions mostly decreased over time however they remained high enough to impact on rice farming which was completely halted in 2011 although further work is required to assess the longer term impact of tsunami inundation flushing of salt with freshwater as well as the possible removal of sandy muddy sediments and underlying soil are recommended to allow crop production to resume

a record of local storms and trans pacific tsunamis eastern banks peninsula new zealand this study of five sand units at lavericks bay new zealand reports on the sedimentary evidence for three trans pacific tsunamis and two local storms the 1868 arica 1877 iquique and 1960 valdivia tsunamis from chile were the largest distantly generated events in new zealand s history but have never before been identified at the same location it is also the first time that the 1877 iquique tsunami deposit has been found in new zealand two further sand units were identified as local storm deposits laid down in 1869 1870 and 1929 the identification and chronology of these events were established through the use of geochemistry palynology diatoms charcoal abundance and historical documents their relative magnitudes were estimated through the use of grain size parameters and lateral extent of the recognisable sand layers the recognisable sandy tsunami deposits extend about 60 of the inundation distance while the storm sediments are finer and less extensive there were two notable geochemical diffe

cretaceous anoxic oxic changes in the moldavids carpathians romania abstract this study focused on the cretaceous black shale successions followed by red shales that crop out at the outer regions of the romanian carpathians in the moldavids the oldest parts of the black shale units deposited in an abyssal plain during late valanginian late barremian time they are mainly characterized by hemipelagic and pelagic muddy siliciclastic rocks and carbonates commonly intercalated with fine grained turbidites during the sedimentation of the middle part of the black shale units in the late barremian early albian interval the depth of the basin increased as the carbonate hemipelagic sedimentation was replaced by a mainly siliceous one only a few thin turbidite intercalations are present the youngest part albian pro parte of the black shale units is characterized by a turbiditic sedimentation with mainly sandy sequences of middle and lower deep water fans we may assume that the depth of the basin continuously decreased the presence of authigenic glauconite in the albian sandstones suggests a palaeoenvironmental change linked to the occurrence of oxygenated turbidity current circulation a significant shift in the sedimentation regime in the eastern carpathian moldavids took place in the late albian when cretaceous oceanic red beds corb occurred this type of sedimentation lasted up to the coniacian the lower part of the corbs that contains radiolarites intercalated with variegated shales pyroclastic tuffs and thin sandstones is interpreted as a hemipelagic and pelagic sedimentation in the abyssal plain environment where rarely turbidites occurred upwards there are mainly burrowed variegated red and green shales the youngest parts of corbs are characterized by increased thickness and frequency of the turbidites while the main part of the corb is carbonate free or has very low carbonate content the upper part of these strata becomes rich in marl and mudstone strata indicating a decrease of the basin depth the accumulation of black shales in the eastern carpathians during the late valanginian late albian interval is linked to the existence of a small silled basin of the moldavian trough in which restricted circulation led to the density stratification of the water column resulting in the deposition of anoxic lower cretaceous sediments i e the black shales because of the tectonic deformation that took place within the lower upper cretaceous boundary interval the restricted circulation had changed to an open circulation regime in the moldavian trough hence the anoxic regime was progressively replaced by an oxic one across the albian cenomanian boundary interval the beginning and the end of the corbs in the moldavid units depend thus on various palaeogeographic and palaeoenvironmental settings and it was controlled by the regional tectonic activity

seismic imaging of melanges pieniny klippen belt case study the authors present results of the first high resolution deep seismic reflection survey in the pieniny klippen belt pkb in poland this survey sheds new light on the matter of olistostromes and the melange character of the pkb the sedimentary mass transport deposits represented by olistoliths and olistostromes manifest themselves by different petrophysical parameters of rocks velocity density and resistivity and seismic attributes seismic attributes are very effective in the interpretation of the geology of complex melanges the authors used selected attributes low pass filter energy energy gradient dip steered median filter prewitt filter laplacian edge enhancing filter and square root of the energy gradient these attributes emphasize changes of the seismic image inside melange zones the distinguished olistoliths are now inside imbricated thrust structures and they are tectonically rearranged polygenetic melanges in the pkb originated as a result of sedimentary and tectonic processes the pkb in the investigated area forms several north vergent thrust sheets belonging to the zlatne and hulina nappes both nappes contain large chaotic non reflective olistoliths as well as the smaller mainly high reflective olistoliths olistoliths are arranged parallel to the flysch layering and thrusts the results presented confirm the postulated two olistostrome belts within the pkb structure

formation of orogen perpendicular thrusts due to mechanical contrasts in the basal decollement in the central external sierras southern pyrenees spain two series of analogue models are used to explore the effect of ductile frictional contrasts of the basal decollement on the development of oblique and transverse structures during thin skinned shortening these models simulate the evolution of the central external sierras ces southern pyrenees spain which constitute the frontal emerging part of the southernmost pyrenean thrust the ces are characterised by the presence of n s to nw se anticlines perpendicular to the pyrenean structural trend and developed in the hanging wall of the thrust system they detach on unevenly distributed triassic materials evaporitic dolomitic interfingering the models simulated the effect of adjacent ductile versus frictional decollements during shortening model series a tests the thickness ratio between overburden and the ductile layer whereas model series b tests the width perpendicular to the shortening direction of frictional decollement model results confirms that deformation reaches further in areas detached on a ductile layer whereas above frictional decollement areas shortening is accommodated by additional uplift and penetrative strain this replicates the structural style of the ces higher structural relief of n s anticlines with regard to orogen parallel structures absence of a representative ductile decollement in the core plunging towards the hinterland and foreland side closure not thrusted by the south pyrenean thrust

mixed diatom floras in sedimentary deposits from the 2016 kaikōura tsunami at little pigeon bay aotearoa new zealand abstract this study records the diatom flora from sedimentary deposits found within a coastal cottage following the november 2016 kaik ura earthquake and tsunami at little pigeon bay banks peninsula aotearoa new zealand unlike previous studies of diatoms from modern tsunami deposits the sediments in this study were isolated from any previous and subsequent reworking of sediments the diatom flora n 117 taxa are dominated by benthic and planktonic lifeforms with preferences for marine 28 brackish marine 25 fresh brackish 19 and fresh water 17 conditions the higher abundances of benthic marine and brackish marine diatoms are attributed to direct in washing and reworking of open ocean water with sandy marine sediments from the sub tidal and inter tidal zones comparatively high percentage counts of benthic fresh brackish and freshwater diatom taxa also indicate significant freshwater sources and sediments from the stream and land adjacent to the cottage fractured and damaged diatom frustules within the flora including broken sponge spicules emphasise dynamic processes of reworking abrasion and erosion during incoming and outgoing tsunami waves likelihood based ordination analysis of the diatom flora indicates statistical differences between the flora in the back area of the cottage and the centre and front areas which we attribute primarily to the influence of different waves that inundated the cottage from the seaward and landward directions such a record affirms a highly mixed diatom flora from multiple sources and habitats it also offers a first modern analogue from aotearoa new zealand to assist future assessments of multi proxy based records of past tsunami events preserved in the geological record

thermochronologic evidence for orogen parallel variability in wedge kinematics during extending convergent orogenesis of the northern apennines italy analysis of 146 new apatite u th he ages six new apatite fi ssion track ages and 165 previously published apatite fi ssiontrack aft ages from the northern apennine extending convergent orogen reveals a signifi cant along strike change in post late miocene wedge kinematics and exhumation history east of 11 30 e age patterns and age elevation relationships are diagnostic of ongoing frontal accretion and slab retreat consistent with a northeastward migrating orogenic wave enhanced erosion rates of 1 mm yr over a period of 3 5 ma are recorded on the contractional pro side of the orogen and 0 3 mm yr on the extending retro side west of 11 30 e ongoing exhumation has been restricted to the range core since at least ca 8 ma at rates of 0 4 mm yr increasing to 1 mm yr in the pliocene ca 3 ma accompanied by post pliocene tilting and associated faulting this pattern can be attributed to either continued convergence but a switch in the transfer of material into the wedge to a regime dominated by underplating or out of sequence shortening or a slowdown or cessation of frontal accretion and slab retreat with enhanced pliocene uplift and erosion triggered by a deeper seated process such as lithospheric delamination complete slab detachment or slab tear these fi ndings emphasize that no single model of wedge kinematics is likely appropriate to explain long term northern apennine orogenesis and synconvergent extension but rather that different lithospheric geodynamic processes have acted at different times in different lateral segments of the orogen

the northern upper rhine graben basin geometry and early syn rift tectono sedimentary evolution a large scale transfer zone subdivides the northern parts of the upper rhine graben into a northern and a southern sub basin these sub basins display the geometry of asymmetric half grabens with opposing tilt directions the transfer zone connects the western master fault of the northern half graben with the eastern master fault of the southern half graben in the northern upper rhine graben early syn rift sedimentation late priabonian to late rupelian was controlled by the tectonically induced subsidence of these half grabens autogenetic as well as by regional third order sea level variations allogenetic within the graben lateral changes in subsidence rates in dip and strike direction of fault blocks controlled the development of accommodation space and thus sediment thickness and facies furthermore a low displacement segment along the western border fault acted as a sediment entry point tectonics controlled the distribution of early syn rift deposits and the palaeogeography of the northern upper rhine graben

the cenozoic lower rhine basin rifting sedimentation and cyclic stratigraphy in the cenozoic the lower rhine basin formed as a rift at the southeastern terminus of the dutch german central graben while the rhenish massif was uplifted the study focusses on the marginal marine and fluvial fill of the lower rhine basin a basin model is developed support for this study was given by extensive industry outcrop and well data by new stratigraphical and sedimentological observations the ingression and subsequent regression of the cenozoic north sea is analysed using the concept of base level cyclicity as the geohistory of the basin was complex a subsidence curve is constructed furthermore an attempt is made to trace the simultaneous uplift of the rhenish massif

tectonic implications of transpression and transtension upper rhine graben 1 seismic reflection data from the upper rhine graben urg show a series of synclines along the linear eastern boundary faults from north of karlsruhe to the jura mountains similar structures do not characterize the northern segment of the graben the synclinal shape is portrayed by inversion related to transpression on the linear boundary faults coupled with the conserved easterly dip of the sediments farther inside the tilted hanging block the onset of transpression preceded the known early burdigalian unconformity but was also an early miocene event it suggests that the regional compression axis 1 in early miocene had a trend between 315 and 0 the continuous transtension in the northern segment suggests that at no time during the history of the urg was the regional 1 horizontal with a ne sw trend the lack of transpressional structures in the younger plio pleistocene sediments along the entire eastern boundary of the urg suggests a late change in the regional stress field the main eastern boundary faults and synclines north and south of baden baden are all continuous and have the same trend kinematically they form a single graben segment and respond to the regional stress in the same way

earthquake hazard assessment through geospatial model and development of eahaasto tool for visualization an integrated geological and geoinformatics approach an earthquake is a natural phenomenon which is very frequent in himalayan region in india in southern peninsula india the spatial occurrence of earthquake is irregular whereas the northeastern the north and the northwestern himalayan parts of india are subjected to regular occurrences of earthquakes as they mark the boundary of the eurasian and the indian plate hence it is important to study and develop spatial model and information tool to understand the seismic phenomenon the geoinformatic technique plays a significant role in the analysis of geodatabase to study the natural disaster and hazard assessment the main aim of the present study is to develop geospatial model based on earthquake hazard assessment tool eahaasto through integrated geological and geoinformatic techniques to better understand the earthquake occurrences zones the spatial and non spatial data were collected and integrated in a gis to prepare geospatial databases the thematic and quantitative databases were generated and analysis was carried out to understand the seismic characteristics of the study area the geospatial model was developed by integrating thematic databases and geospatial analyzed using weighted linear combination method finally the gis based on customized eahaasto was developed to visualize the output of the model in qualitative and quantitative forms

the 2016 kaikōura earthquake simultaneous rupture of the subduction interface and overlying faults abstract the distribution of slip during an earthquake and how it propagates among faults in the subduction system play a major role in seismic and tsunami hazards yet they are poorly understood because offshore observations are often lacking here we derive the slip distribution and rupture evolution during the 2016 mw 7 9 kaik ura new zealand earthquake that reconcile the surface rupture space geodetic measurements seismological and tsunami waveform records we use twelve fault segments with eleven in the crust and one on the megathrust interface to model the geodetic data and match the major features of the complex surface ruptures our modeling result indicates that a large portion of the moment is distributed on the subduction interface making a significant contribution to the far field surface deformation and teleseismic body waves the inclusion of local strong motion and teleseismic waveform data in the joint inversion reveals a unilateral rupture towards northeast with a relatively low averaged rupture speed of 1 5 km s the first 30 s of the rupture took place on the crustal faults with oblique slip motion and jumped between fault segments that have large differences in strike and dip the peak moment release occurred at 65 s corresponding to simultaneous rupture of both plate interface and the overlying splay faults with rake angle changes progressively from thrust to strike slip the slip on the papatea fault produced more than 2 m of offshore uplift making a major contribution to the tsunami at the kaik ura station while the northeastern end of the rupture can explain the main features at the wellington station our inversions and simulations illuminate complex up dip rupture behavior that should be taken into consideration in both seismic and tsunami hazard assessment the extreme complex rupture behavior also brings new challenges to the earthquake dynamic simulations and understanding the physics of earthquakes

different modes of the late cretaceous early tertiary inversion in the north german and polish basins several selected seismic lines are used to show and compare the modes of late cretaceous early tertiary inversion within the north german and polish basins these seismic data illustrate an important difference in the allocation of major zones of basement thick skinned deformation and maximum uplift within both basins the most important inversion related uplift of the polish basin was localised in its axial part the mid polish trough whereas the basement in the axial part of the north german basin remained virtually flat the latter was uplifted along the sw and to a smaller degree the ne margins of the north german basin presently defined by the elbe fault system and the grimmen high respectively the different location of the basement inversion and uplift within the north german and polish basins is interpreted to reflect the position of major zones of crustal weakness represented by the wnw ese trending elbe fault system and by the nw se striking teisseyre tornquist zone the latter underlying the mid polish trough therefore the inversion of the polish and north german basins demonstrates the significance of an inherited basement structure regardless of its relationship to the position of the basin axis the inversion of the mid polish trough was connected with the reactivation of normal basement fault zones responsible for its permo mesozoic subsidence these faults zones inverted as reverse faults facilitated the uplift of the mid polish trough in the order of 1 3 km in contrast inversion of the north german basin rarely re used structures active during its subsidence basement inversion and uplift in the range of 3 4 km was focused at the elbe fault system which has remained quiescent in the triassic and jurassic but reproduced the direction of an earlier variscan structural grain in contrast n s oriented mesozoic grabens and troughs in the central part of the north german basin avoided significant inversion as they were oriented parallel to the direction of the inferred late cretaceous early tertiary compression the comparison of the north german and polish basins shows that inversion structures can follow an earlier subsidence pattern only under a favourable orientation of the stress field a thick zechstein salt layer in the central parts of the north german basin and the mid polish trough caused mechanical decoupling between the sub salt basement and the supra salt sedimentary cover resultant thin skinned inversion was manifested by the formation of various structures developed entirely in the supra salt mesozoic cenozoic succession the zechstein salt provided a mechanical buffer accommodating compressional stress and responding to the inversion through salt mobilisation and redistribution only in parts of the ngb and mpt characterised by either thin or missing zechstein evaporites thick skinned inversion directly controlled inversion related deformations of the sedimentary cover inversion of the permo mesozoic fill within the mid polish trough was achieved by a regional elevation above uplifted basement blocks conversely in the north german basin horizontal stress must have been transferred into the salt cover across the basin from its sw margin towards the basins centre this must be the case since compressional deformations are concentrated mostly above the salt and no significant inversion related basement faults are seismically detected apart from the basin margins this strain decoupling in the interior of the north german basin was enhanced by the presence of the elbe fault system which allowed strain localization in the basin floor due to its orientation perpendicular to the inferred late cretaceous early tertiary far field compression

effects of inundation by the 14th november 2016 kaikōura tsunami on banks peninsula canterbury new zealand at 12 02 56 a m monday november 14 2016 nzdt 11 02 56 a m november 13 2016 utc a magnitude 7 8 earthquake struck near kaik ura on the north eastern coast of the south island of new zealand this earthquake caused a tsunami along new zealand s east coast that was recorded on a number of sea level gauges outside of the kaik ura region north facing bays along banks peninsula were most affected by the tsunami of these little pigeon bay experienced extensive inundation and an unoccupied cottage was destroyed by the wave run up we report on the inundation extent and inferred flow directions at little pigeon bay including a study on temporal changes in the field evidence of this inundation preliminary modelling results indicate that the waves may have excited resonance in the bay we also present results from inundation surveys of nearby north facing bays on banks peninsula the excitation of resonance in little pigeon bay provides an explanation for the more severe inundation and damage there in comparison to these nearby bays

tracing tectonic deformation using the sedimentary record an overview tectonic activity on a range of scales is a fundamental control on sedimentary activity the range of structural deformation within a region extends from the plate tectonic scale governing for example rift initiation to the basin scale with the formation of basin bounding faults internal basin configuration is also strongly influenced by tectonic activity however the relationship between tectonic activity and sedimentation is a complex one given the many additional factors which can also influence sedimentary activity including erosion sediment transport source area lithology groundwater chemistry range of depositional environments climate eustasy and the relative location of an area and its distality to marine influences in this paper we provide a selective overview of the issues associated with the interlinked themes of tectonics and sedimentation examining the main basin types forming in both extensional and compressional plate settings we then review the various models of sedimentation in the selected basins both on a local and a basinal scale finally we look to the future providing a series of possible research areas almost exclusively multidisciplinary which would help to improve existing models of interlinked sediment tectonics systems

tectonostratigraphic evolution of the carboniferous arc related basin in the east junggar basin northwest china insights into its link with the subduction process abstract the junggar basin in northwest china is located in the southern part of central asian orogenic belt caob the tectonic mechanisms controlling sedimentary fill through space and geologic time within dynamic subduction environments remains poorly understood in the junggar basin this paper presents an integrated tectonostratigraphic and tectonic evolution of carboniferous volcanic arcs and associated basin in the east junggar basin using multichannel seismic reflection data well line data geochronological and geochemical data we propose a new tectonic sedimentary model for the east junggar basin during the carboniferous time based on geochemistry of volcanic rocks and four seismic tectonostratigraphic sequences the carboniferous succession of volcanogenic sediments represents progradational sequences mainly supplied from the northeast the negative ta nb and ti anomalies low rb ba ratios 0 01 0 15 and high incompatible trace element such as th u abundances of the basalts suggest that metasomatism may have occurred during the late carboniferous subduction the northeastward increase of the ba la ration k ca and decrease of na ti and fe indicate the northeast dipping subduction polarity in the east junggar basin during the early carboniferous tectonism in the east junggar basin took place in two stages deep marine sediments widely covered the junggar region and then the depocenter slightly shifted towards southwest which probably resulted from the northeast dipping subduction that led to the southwestward tilting of the dinan area during the early stage of the late carboniferous mixed marine and nonmarine deposits initially onlapped the volcanic arc towards the northeast and then gradually downlapped to the southwest at the end of the late carboniferous subduction of the junggar ocean continued towards northeast and depositional environment became nonmarine the main axis of the depocenter rapidly migrated towards southwest that resulted from the southwestward tilting of the luliang region

far field tsunami hazard in new zealand ports we present the results of a numerical modeling study investigating the effects of far field tsunamis in new zealand ports four sites marsden point tauranga harbor port taranaki and lyttelton harbor were selected based on a combination of factors such as economic importance and the availability of historical and or instrumental data numerical models were created using the commit tsunami modeling tool and the method of splitting tsunami most hydrodynamic model comparison of model results to measured data from recent historical events showed that for particular sites and events the model correlated well with the timing and amplitude of the observed tsunami and in most cases there was generally good agreement between the and modeled tsunami heights and current speeds a sensitivity analysis for tsunami heights and current speeds was conducted using a suite of large m w 9 tsunamigenic earthquake sources situated at regular 15 intervals in azimuth along the pacific rim while another set of scenarios focused on regional tsunami sources in the southwest pacific model results were analyzed for tsunami heights and current speeds as a function of the source region in terms of currents the analysis identified where speeds were greatest and which source was responsible results suggested that tsunamis originating from central america produced the strongest response in new zealand the modeling was also used to determine the timing and duration of potentially dangerous current speeds as well as minimum safe depths for vessel evacuation offshore this study was motivated by the desire to reduce damage and operational losses via improved forecasting of far field tsunamis at new zealand ports it is important that forecasts are accurate since tsunami damage to ships and facilities is expensive and can be mitigated given timely warnings and because preventable false alarms are also costly in terms of lost productivity the modeling presented here will underpin efforts to produce port specific guidance and information in the event of future pacific tsunamis

late orogenic vertical movements within the arc of the sw alps and ligurian alps abstract mainly on the basis of seismic data we reconstruct magnitude and timing of miocene to present vertical movements in the region of the savigliano basin an up to 4 km thick succession of neogene to quaternary sediments accumulated inside the alpine arc at the western termination of the po plain we focus in particular on the margins of the basin which are the link between the mountain range and the subsiding basin seismic data from these regions allow for the definition of upward and downward vertical movements uplift exhumation and subsidence with a spatial and temporal resolution which cannot be attained by other methods the eastern southern and western margins of the savigliano basin display very different geometries of the sedimentary bodies and therefore document different vertical movements during miocene to present times the eastern part of the savigliano basin and the regions to the e experienced subsidence followed by exhumation the southern margin of the basin in the cuneo area was much more stable with miocene to present formations all pinching out close to the present day outcropping position of the basement sedimentary cover contact in the w seismic sections record a stage of tilting until the burdigalian followed by generalized subsidence which affected also the adjacent regions of the sw alps the overall pattern of vertical movements is essentially controlled by the nw ward migration of a syncline anticline couple with the synclinal axis presently located in the center of the savigliano basin the width of the folds is in the order of 30 60 km 1 2 wavelength in map view the trace of the fold axes changes from n s in the savigliano basin to e w in the alessandria basin

quaternary structural partitioning within the rigid tarim plate inferred from magnetostratigraphy and sedimentation rate in the eastern tarim basin in china abstract it has been proposed that within the tarim basin tectonic activity has been limited since triassic time however on the basis of magnetostratigraphy from the eastern tarim basin which defines the chronology of sedimentation and structural evolution of the basin we show that the basin interior has been uplifted and partitioned during quaternary the magnetostratigraphy was constructed from 2228 samples that yielded acceptable inclination values characteristic remnant magnetization chrm with both normal n1 n11 and reversed r1 r11 polarity was isolated by thermal demagnetization the data correlate best with polarity chrons c3r to c1n which range from 5 39 ma to recent on the geological time scale 2004 gts2004 an abrupt decrease in the sedimentation rate is observed at 1 77 ma in the ls1 core this change does not overlap with known pleistocene climate change events we attribute this sedimentation rate decrease to a structurally controlled local decrease in accommodation space where basin basement uplifts occur this period of sedimentary environmental change reveals that structural partitioning in the basement of the tarim basin occurred since 1 77 ma and we speculate that tilting of the southeast uplift a sub basin unit within the tarim basin began in early pleistocene time

structure and tertiary tectonic history of the mulhouse high upper rhine graben block faulting modified by changes in the alpine stress regime 1 the mulhouse high horst is situated in the southernmost upper rhine graben and changes in its tectonic history record the interaction with the adjacent alpine front recently released seismic data show that the mulhouse high consists of the sierentz and the altkirch tilted blocks separated by the ferrette fault zone with a throw of several hundred meters during the eocene early rupelian main rifting phase the mulhouse high was the elevated flank of the dannemarie basin with sedimentation affected by the nearby southern boundary of the rhine graben the miocene jura compression extended into the mulhouse high creating a series of semiparallel buried folds with no evidence for thin skin tectonics the change to a nw se regional compressive stress reactivated the main graben faults as wrench faults it also resulted in transpression on the ne sw trending faults particularly the northern segment of the illfurth fault zone consequently the northern part of the mulhouse high was uplifted strike slip motion along the ferrette fault zone is shown to be small

tracing tectonic deformation using the sedimentary record the study of sediments and sedimentary basins in terms of their tectonic environment requires a multidisciplinary approach and has increasingly drawn both techniques and objectives from fields outside sedimentology the application of different theoretical experimental and empirical resources provided by structural geology geochemistry geophysics scale modelling and field geology complement sedimentological methods with the combined aim of achieving a deeper understanding of the origins evolution and significance of sedimentary sequences in terms of their tectonic history studies presented in this volume range across a wide spectrum from the analysis of sedimentary sequence architecture at basin scale down to the chemical properties of individual grains and include studies from a range of tectonic settings the volume will be of interest to those involved with or contemplating studies involving the linkages between tectonics and sedimentation as well as a wider audience to whom the results of such studies may provide fresh insight

cambrian palaeomagnetic data confirm a natal embayment location for the ellsworth whitmore mountains antarctica in gondwana reconstructions summary the ellsworth whitmore mountains ewm are one of five terranes that form west antarctica constraining the positions of these terranes in pre break up gondwana is crucial to understanding the history of the palaeo pacific gondwana margin we report the results of a detailed palaeomagnetic investigation of the ewm which comprises some 150 sites in six formations ranging in age from cambrian to permian five of the studied units yield only viscous remnant magnetizations of recent age or unstable natural remanent magnetizations the remaining unit the mid late cambrian frazier ridge formation yielded stable magnetizations at 16 of 35 sites this component passes a fold test at the 95 per cent confidence level indicating that it pre dates permian deformation and we argue that it is of primary origin the resulting palaeopole 9 n 293 e a95 5 1 is in good agreement with two previously published palaeopoles from similarly aged rocks in the ewm collectively these data indicate that the ewm were located in the natal embayment prior to gondwana break up and underwent 90 of anticlockwise rotation during break up all three studies however yield inclinations

comparison of the 2010 chile and 2011 japan tsunamis in the far field in this study we analyze water level data from coastal tide gauges and deep ocean tsunameters to explore the far field characteristics of two major trans pacific tsunamis the 2010 chile and the 2011 japan tohoku oki events we focused our attention on data recorded in california 14 stations and new zealand 31 stations as well as on tsunameters situated along the tsunami path and proximal to the study sites our analysis considers statistical analyses of the time series to determine arrival times of the tsunami as well as the timing of the largest waves and the highest absolute sea levels fourier and wavelet analysis were used to describe the spectral content of the tsunami signal these characteristics were then compared between the two events to highlight similarities and differences between the signals as a function of the receiving environment and the tsunami source this study provides a comprehensive analysis of far field tsunami characteristics in the pacific ocean which has not experienced a major tsunami in nearly 50 years as such it systematically describes the tsunami response characteristics of modern maritime infrastructure in new zealand and california and will be of value for future tsunami hazard assessments in both countries

sedimentary and geochemical signature of the 2016 kaikōura tsunami at little pigeon bay a depositional benchmark for the banks peninsula region new zealand abstract the 14 november 2016 kaik ura tsunami inundated little pigeon bay in banks peninsula new zealand and left a distinct sedimentary deposit on the ground and within the cottage near the shore sedimentary grain size and geochemical electrical conductivity and x ray fluorescence analyses on samples collected over successive field campaigns are used to characterize the deposits sediment distribution observed in the cottage in combination with flow direction indicators suggests that sediment and debris laid down within the building were predominantly the result of a single wave that had been channeled up the stream bed rather than from offshore salinity data indicated that the maximum tsunami wetted and or seawater sprayed area extended 12 5 m farther inland than the maximum inundation distance inferred from the debris line observed a few days after the event in addition the salinity signature was short lived an overall inland waning of tsunami energy was indicated by the mean grain size and portable x ray fluorescence elemental results itrax data collected from three cores along an inland transect indicated a distinct elevated elemental signature at the surfaces of the cores with an associated increase in magnetic susceptibility comparable signatures were also identified within subsurface stratigraphic sequences and likely represent older tsunamis known to have inundated this bay as well as adjacent bays in banks peninsula the sedimentary and geochemical signatures of the 2016 kaik ura tsunami at little pigeon bay provide a modern benchmark that can be used to identify older tsunami deposits in the banks peninsula region

graben width controlling syn rift sedimentation the palaeogene southern upper rhine graben as an example eocene to early oligocene syn rift deposits of the southern upper rhine graben urg accumulated in restricted environments sedimentation was controlled by local clastic supply from the graben flanks as well as by strong intra basinal variations in accommodation space due to differential tectonic subsidence that in turn led to pronounced lateral variations in depositional environment three large scale cycles of intensified evaporite sedimentation were interrupted by temporary changes towards brackish or freshwater conditions they form three major base level cycles that can be traced throughout the basin each of them representing a stratigraphic sub unit a relatively constant amount of horizontal extension l in the range of 4 5 km has been estimated for the urg from numerous cross sections the width of the rift lf however varies between 35 and more than 60 km resulting in a variable crustal stretching factor between the bounding masterfaults apart from block tilting tectonic subsidence was therefore largely controlled by changes in the initial rift width l0 the along strike variations of the graben width are responsible for the development of a deep trough like evaporite basin potash basin in the narrowest part of the southern urg adjacent to shallow areas in the wider parts of the rift such as the colmar swell in the north and the rhine bresse transfer zone that delimits the urg to the south under a constant amount of extension the along strike variation in rift width is the principal factor controlling depo centre development in extensional basins

provenance of cretaceous clastics in the subhercynian basin constraints to exhumation of the harz mountains and timing of inversion tectonics in central europe the harz mountains and the adjacent subhercynian cretaceous basin figure as the most prominent surface representative for late cretaceous inversion structures in central europe facies depositional architecture and provenance of the basin fill reflect mechanisms and timing of the exhumation of the harz from hauterivian to early santonian there is no evidence for detrital input from the nearby harz area sediments are mature quartzarenites derived from paleozoic basement rocks and or recycled permian to mesozoic sedimentary rocks this situation changed drastically in middle to late santonian when freshly exhumed and eroded mesozoic sedimentary cover rocks of the harz were delivered into the basin feldspar and lithoclasts reflect erosion of triassic and in places jurassic to turonian strata apatite and garnet in heavy mineral spectra are derived from largely unweathered lower triassic buntsandstein as indicated by apatite and garnet chemistry in early campanian paleozoic lithoclasts indicate erosion cutting down into the basement of the harz simultaneous strong decrease of feldspar garnet and apatite suggest an almost complete removal of the 2 3 km thick mesozoic cover of the harz within only 2 4 myr this translates into an exhumation rate of approximately 1 mm a consistent with apatite fission track data from granitoid rocks of the harz mountains

upper rhine graben role of preexisting structures during rift evolution 1 the evolution of the cenozoic upper rhine graben was controlled by a repeatedly changing stress field and the reactivation of a complex set of crustal discontinuities that had come into evidence during permo carboniferous times a comparison of the spatial and temporal thickness distribution of synrift deposits with preexisting fault patterns permits to infer a sequence of distinct basin subsidence phases that can be related to changes in the ambient stress field reactivation of a system of late palaeozoic fault systems outlining troughs and highs controlled the nucleation of initially separated middle and late eocene basins the depocenters of which coincided with a preexisting wsw ene trend during oligocene crustal extension the individual basins coalesced resulting in the development of the ssw nne striking upper rhine graben during the late oligocene chattian change in stress field the upper rhine graben was probably reactivated as a dextral strike slip system with the central graben segment forming a releasing bend during the early miocene aquitanian a major reorientation of the regional stress field is held responsible for the main subsidence phase of the northern parts of the upper rhine graben this is reflected by a counterclockwise rotation and northeastward shift of the depocenter axis and later by the middle miocene uplift and erosion of the southern parts of the upper rhine graben during the plio quaternary the upper rhine graben was reactivated as a sinistral strike slip system with the central graben segment forming a restraining bend

magmatic belts in accretionary margins a key for tectonic evolution the tonalite belt of north victoria land east antarctica occurring in the early palaeozoic palaeomargin of the east antarctica craton the tonalite belt of north victoria land is a narrow linear magmatic belt up to 200 km long made up of strongly foliated tonalitic and granodioritic intrusions they were synkinematically emplaced into the lanterman murchison shear zone a major tectonic structure across which different tectono metamorphic terranes were accreted during the late cambrian ross orogeny the deformational and kinematic features of the intrusions indicate that strain and displacement during terrane accretion were partitioned into oblique thrust high angle thrust and strike slip shear zones from this it is deduced that a transpressional regime prevailed during early palaeozoic deformation and terrane accretion this and other magmatic belts which exploited major tectonic structures in collisional margins such as the coast plutonic complex of nw america are basic keys for understanding deformational processes and kinematic regimes during terrane accretion moreover the occurrence of such types of magmatic belts might be regarded as a reliable indication of large scale strike slip motion between accreting terranes in an oblique convergent setting

a new post early cambrian archaeocyath from antarctica a new species of archaeocyath sponge dictyocyathus neptunensis is described from the lower third of the nelson limestone of the neptune range antarctica based on the presence of the trilobites nelsonia schesis and amphoton oatesi these strata are interpreted to be mid to late middle cambrian in age d neptunensis shows a branching low integration modular form and a very simple skeletal type such an organization is predicted from known morphological trends within the early cambrian archaeocyatha specimens are not in life position and probably form part of a storm deposit the absence of dictyocyathus from latest early cambrian toyonian strata worldwide suggests a convergent nature for this highly simplified skeletal type in archaeocyaths

determining flow patterns and emplacement dynamics from tsunami deposits with no visible sedimentary structure in the absence of eyewitness reports or clear sedimentary structures it can be difficult to interpret tsunami deposits or reconstruct tsunami inundation patterns the emplacement dynamics of two historical tsunami deposits were investigated at seven transects in okains bay new zealand using a combined geospatial geomagnetic and sedimentological approach the tsunami deposits are present as layers of sand and silt intercalated between soils and become finer and thinner with distance inland the deposits are attributed to the 1960 and possibly the 1868 tsunamis based on radiometric dating and correlation with historical records measurements of magnetic fabric mf anisotropy of magnetic susceptibility and particle size were used to reconstruct the evolution of flow dynamics laterally and vertically a combination of statistical methods including spatial autocorrelation testing spearman s rank order correlation principal component analysis pca and k means cluster analysis was applied to examine relationships between mf parameters and sediment texture and infer depositional hydrodynamics flow patterns deduced from mf show the estuary channel acted as a conduit for inundation with flow commonly aligned sub perpendicular to the estuary bed mf and sediment data suggest deposition occurred from settling during laminar flow evidence of both uprush and backwash deposition as well as wave reflection from infrastructure was found statistical analysis of data showed significant relationships between grain size parameters and mf parameters associated with flow speed and magnetic fabric type pca and cluster analysis differentiated samples into two primary hydrodynamic groups 1 samples deposited from laminar flow and 2 samples deposited close to the limit of inundation which includes samples deposited further inland those affected by flow convergence and those in the upper part of tsunami deposits this approach has potential as a tool for reconstructing hydrodynamic conditions for palaeotsunamis and by combining spatial and statistical analyses large scale investigations can be more easily performed this article is protected by copyright all rights reserved

tsunami runup and tide gauge observations from the 14 november 2016 m7 8 kaikōura earthquake new zealand the 2016 m w 7 8 kaik ura earthquake was one of the largest earthquakes in new zealand s historical record and it generated the most significant local source tsunami to affect new zealand since 1947 there are many unusual features of this earthquake from a tsunami perspective the epicentre was well inland of the coast multiple faults were involved in the rupture and the greatest tsunami damage to residential property was far from the source in this paper we summarise the tectonic setting and the historical and geological evidence for past tsunamis on this coast then present tsunami tide gauge and runup field observations of the tsunami that followed the kaik ura earthquake for the size of the tsunami as inferred from the measured heights the impact of this event was relatively modest and we discuss the reasons for this which include the state of the tide at the time of the earthquake the degree of co seismic uplift and the nature of the coastal environment in the tsunami source region

high resolution seismic survey on the rhine river in the northern upper rhine graben in the northern part of the upper rhine graben urg a high resolution seismic reflection survey was carried out on the rhine river over a length of 80 km and on its tributary neckar over a length of 25 km the seismic investigation provides new results to redefine the base of quaternary fluvial sediments from oppenheim upstream to the south of mannheim the standard quaternary thickness map of bartz 1974 was partially revised and completed maximum pleistocene sediment thickness is documented in the area of mannheim with approximately 225 m the top of the pliocene in this area is sub horizontal and not faulted and rises downstream continuously towards the fault block of worms intercalated lacustrine pelitic layers play a main role in defining the litho stratigraphy in this part of the urg in the north of worms pleistocene sediments are mainly coarse grained in the area of worms a pleistocene tectonic phase along n s striking normal faults with variable displacement along the strike is obvious

tectonic history of the ellsworth mountains west antarctica reconciling a gondwana enigma early paleozoic orogenesis has been recognized along the southern african saldanian orogeny and east antarctic ross orogeny sectors of the gondwana paleo pacific margin however the absence of a contemporaneous orogenic event in the ellsworth mountains of west antarctica once a contiguous part of this margin has resulted in their geology being considered enigmatic in this contribution widespread detailed structural studies from all stratigraphic levels of the ellsworth mountains allow their tectonic evolution to be reassessed geochemical stratigraphic and structural data indicate that the middle to upper cambrian heritage group developed in a continental rift basin multiple observations of the crucial end cambrian contact between this rift sequence and the overlying crashsite group reveal the contact to be regionally conformable there are localized outcrop scale unconformities furthermore structural continuity can be demonstrated across this key boundary thus precluding the possibility of an end cambrian orogenic event the entire stratigraphic succession was affected by two post permian phases of deformation d1 structures are locally developed and superimposed by the main dextral transpressive d2 permian triassic gondwanian deformation event d2 is succeeded by an episode of extension orthogonal to orogenic strike recent geochronological data on the early paleozoic evolution of the cape fold belt reveal a strong tectonostratigraphic correlation with the ellsworth mountains indicating that this sector of the gondwana paleo pacific margin was affected by middle to late cambrian rifting a new tectonic model is proposed for the southwestern paleo pacific margin of gondwana that accounts for the presence of rifting along a margin otherwise dominated by active subduction

palaeomagnetic dating and tectonic significance of dolerite intrusions in the albany mobile belt western australia abstract dolerite dykes and sills in the mesoproterozoic albany mobile belt and neoproterozoic stirling range formation metasediments in southwestern australia provide evidence for extensional events between australia east antarctica and greater india paleomagnetic analysis shows that primary remanence was carried by single domain magnetite for samples from seven localities palaeomagnetic poles for the majority of sites fall close to the earliest cambrian part of the australian apparent polar wander path apwp the interpreted earliest cambrian dykes intrude both extensional dominant and shear fractures indicating nne ssw extension between the western australian and east antarctic shields and a horizontal ese wnw maximum compressive stress dyke emplacement appears to be contemporaneous with mafic volcanism in central and northern australia and igneous intrusion in once contiguous parts of the east antarctic shield these features are interpreted as being related to gondwanaland assembly and may represent a response to far field stresses resulting from the collision between east and west gondwanaland a second suite of nw striking mid carboniferous dykes is related to ne sw extension and rifting between greater india and the western australian shield during early stages in the formation of the perth basin in a sinistral transtensional regime along the southern western australian margin a palaeopole from the primary remanence in a nnw striking dolerite dyke falls on the poorly defined triassic to early cretaceous part of the australian apwp indicating a possible third phase of dyke emplacement regional tectonic constraints for rifting in the perth basin suggest that this youngest dyke most likely intruded during the triassic

possible dual earthquake landslide source of the 13 november 2016 kaikoura new zealand tsunami a complicated earthquake m w 7 8 in terms of rupture mechanism occurred in the ne coast of south island new zealand on 13 november 2016 utc in a complex tectonic setting comprising a transition strike slip zone between two subduction zones the earthquake generated a moderate tsunami with zero to crest amplitude of 257 cm at the near field tide gauge station of kaikoura spectral analysis of the tsunami observations showed dual peaks at 3 6 5 7 and 5 7 56 min which we attribute to the potential landslide and earthquake sources of the tsunami respectively tsunami simulations showed that a source model with slip on an offshore plate interface fault reproduces the near field tsunami observation in terms of amplitude but fails in terms of tsunami period on the other hand a source model without offshore slip fails to reproduce the first peak but the later phases are reproduced well in terms of both amplitude and period it can be inferred that an offshore source is necessary to be involved but it needs to be smaller in size than the plate interface slip which most likely points to a confined submarine landslide source consistent with the dual peak tsunami spectrum we estimated the dimension of the potential submarine landslide at 8 10 km

early palaeozoic rather than neoproterozoic volcanism and rifting within the transantarctic mountains new u pb dating of zircons separated from felsic volcanic rocks of the patuxent and gambacorta formations from the pensacola mountains in the transantarctic mountains antarctica yields earliest ordovician ages of 500 8 and 501 3 ma respectively the dated felsic volcanic rock of the gorecki felsite member of the patuxent formation is important tectonically as the felsite together with mafic volcanic rocks were previously considered to provide key evidence of a neoproterozoic rifting event prior to separation of laurentia from east antarctica the new data do not necessarily refute this event but indicate a previously unrecognized early ordovician period of bimodal magmatism and extension along the transantaractic mountains

end of the kiaman superchron in the permian of sw england magnetostratigraphy of the aylesbeare mudstone and exeter groups the chronology of permian strata in sw england is fragmentary and largely based on radiometric dating of associated volcanic units magnetostratigraphy from the c 2 km of sediments in the exeter and aylesbeare mudstone groups was undertaken to define a detailed chronology using the end of the kiaman superchron and the overlying reverse and normal polarity in the middle and upper permian as age constraints the palaeomagnetic directions are consistent with other european permian palaeopoles with data passing fold and reversal tests the end of the kiaman superchron in the wordian occurs in the uppermost part of the exeter group the overlying aylesbeare mudstone group is early capitanian to latest wuchiapingian in age the changhsingian and most of the lower triassic sequence is absent magnetostratigraphic comparison with the southern permian basin shows that the exeter and aylesbeare mudstone groups are closely comparable in age with the havel and elbe subgroups of the rotliegend ii succession the altmark unconformities in these successions appear similar in age to the sequence boundaries in sw england indicating that both may be climate controlled clasts in the exeter group from unroofing of the dartmoor granite first occurred at a minimum of c 8 myr after formation of the granite supplementary material additional sampling magnetic fabric and palaeomagnetic data are available at http doi org 10 6084 m9 figshare c 3283400

deep crustal structure of the rhine graben from dekorp ecors seismic reflection data a summary abstract results of two deep reflection seismic lines crossing the northern and southern part of the rhine graben which were recorded in 1988 by the french ecors and the german dekorp teams indicate that the asymmetry of this rift persists to the base of the crust the brittle ductile transition zone approximately coincides with the top of the lower crust ductile shear zones appear to affect the crust mantle boundary upper crustal extension by faulting accounts for a divergence of the graben flanks by 5 7 km whereas the crustal configuration of the rhine graben suggest an extension value of some 17 km

assessment of morphometric parameters for the development of relative active tectonic index and its significant for seismic hazard study an integrated geoinformatic approach earthquake is a geological natural hazard which is shaking of earth s surface due to seismic activity the himalayan region and quaternary geological surface of indian sub continent had experienced several earthquakes in the recent geological period due to reactivation of existing faults surface drainage system and its morphometric characteristics are controlled by subsurface geo structural features and active tectonic process which have greater impact on seismic activity thus the present study focuses on the analysis of morphometric parameters for the development of relative active tectonic index rati and its significant for seismic hazard assessment using geoinformatics the different morphometric parameters have been analyzed and geospatial databases have been generated the rati has been estimated by considering higher priority tectonic influencing parameters based on principal component analysis pca methods and the output has also been integrated with thematic and seismological databases to understand its significance for seismotectonic activity the result shows that the very high and high relative active tectonic index are observed in greater and lesser himalayan sequence where frequency of earthquake and its magnitudes are also high the anomalous nature of drainage network compressed meander in youthful stage presence of high resistance rocks structural control on drainage network relief steepness and v shaped narrow valley are the indicator of active tectonics and seismic activity in this region even though the foothills micro basin shows moderate or low relative active tectonic index morphometric analysis depicts that it is highly elongated in nature with significant surface tilt and have a greater influence of tectonic deformation in addition the continuous stress from main frontal thrust has a significant role for the landscape upliftment and seismic activity in this region the micro basin which is located in the quaternary alluvial surface has not produced any major earthquake in the past but has greater influence on tectonic activity and may produce earthquake in the future

south american tsunamis in lyttelton harbor new zealand at 2347 utc on april 1 2014 12 47 pm april 2 2014 nzdt an earthquake with a moment magnitude of 8 2 occurred offshore of iquique in northern chile the temblor generated a tsunami that was observed locally and recorded on tide gauges and deep ocean tsunameters close to the source region while real time modeling based on inverted tsunameter data and finite fault solutions of the earthquake rupture suggested that a damaging far field tsunami was not expected and later confirmed this event nevertheless reminded us of the threat posed to new zealand by tsunami generated along the west coast of south america and from the peru chile border region in particular in this paper we quantitatively assess the tsunami hazard at lyttelton harbor from south american tsunamis through a review of historical accounts numerical modeling of past events and analysis of water level records a sensitivity study for tsunamis generated along the length of the south american subduction zone is used to illustrate which section of the subduction zone would generate the strongest response at lyttelton while deterministic scenario modeling of significant historical south american tsunamis i e 1868 1877 and 1960 provide a quantitative estimate of the expected effects from possible future great earthquakes along the coast of south america

evidence of major middle cambrian deformation in the ross orogen antarctica long lived polyphase tectonism in the cambrian history of the ross orogen is demonstrated by recent stratigraphic studies in both the central and weddell sea segments of the transantarctic mountains we postulate that strong early middle cambrian deformation preceded a more widely recognized late cambrian early ordovician period of contraction and magmatism these middle cambrian movements were locally the principal phase of orogenic deformation they profoundly altered sedimentation patterns along the antarctic margin so that in the weddell sea region when carbonate platform sedimentation resumed the platform margin was reestablished far oceanward of its early cambrian location intra cambrian tectonism along the paleo pacific margin of gondwana was not confined to its antarctic segment comparable activity recently has been described from australia and is known from south america these movements may be related to amalgamation of east and west gondwana

multi proxy evidence for small historical tsunamis leaving little or no sedimentary record abstract there has been considerable progress in tsunami research in recent years yet most work has been focussed on identifying and understanding the evidence of large events this study aimed to identify the evidence of small historical tsunamis in lyttelton harbour new zealand the study area has been inundated by multiple relatively small historical tsunamis that left atypical sedimentary evidence no sand or no sediment shallow trenches revealed discontinuous layers of small grey mud clasts at various depths across the study area most likely transported from the nearby tidal flats the origin of these mud clast layers was investigated using a multi proxy approach comprising sedimentological geochemical and diatom analyses complemented by dating from 137cs activity profiles and historical data subtle variations consistent with inclusions of marine mud such as a decrease in organic content and magnetic susceptibility and increases in geochemical markers e g ca kcps k kcps k rb si rb and sr rb were found in the sediment profile variations in diatom assemblages suggesting a marine influence were also recorded at similar depths aligning with layers of mud clasts using 137cs activity profiles and historical data these deposits were attributed to the 1960 chile valdivia and 1964 alaska tsunamis as well as a possible earlier event sedimentary evidence for the 2010 chile maule tsunami was not found at the study site but geochemical analysis of surface samples revealed marked changes in ca cl sr and ti concentrations indicative of a change from a terrestrial to marine influence this was used to identify the landward extent of inundation by the 2010 event ultimately this study shows that a broad multi proxy analysis can distinguish even the subtle signatures of an inconspicuous deposit laid down by a small tsunami

kinematic evolution of thrusts wedge and erratic line length balancing insights from deformed sandbox models kinematic evolution of fold thrust structures has been investigated by analogue models that include syntectonic sedimentation different decollement dips and basement thicknesses produced different wedge geometries and propagating characteristics a model with one decollement level was characterized by a closely spaced thrust system during early stages of shortening as compared to the late stages the frequency of fault nucleation was rapid during the early stages of deformation conversely the frequency of fault nucleation was low and thrust spacing was significantly wider in a model with two decollement levels individual faults became locked at steep dips and deformation stepped forward as a new fault nucleated in sequence in front of the older locked structure once the thrust system was established up to 27 overall shortening an overlying bed was introduced to simulate syntectonic deformation model sand wedge did not grow self similarly but rather its length and height increased episodically with deformation restoration of deformed models show that layer parallel shortening accommodated for approximately half of the total model shortening across the multilayers calculated error in apparent layer shortening from the restored layers revealed a direct relation with depth of the layers in the models the experimental results are comparable to a natural example from the northern apennines fold and thrust belts

provenance of late palaeozoic metasediments of the sw south american gondwana margin a combined u pb and hf isotope study of single detrital zircons combined u pb and lu hf isotope measurements of single detrital zircon grains in carboniferous metasediments from patagonia delineate the source areas of the sediments the detritus represented by four metasandstone samples was deposited prior to onset of subduction in late carboniferous time along the south patagonian proto pacific gondwana margin a broad series of detrital zircon age peaks 0 35 0 7 ga 0 9 1 5 ga and a large spread 0 3 3 5 ga in the age spectra require numerous sources a fifth metasediment was deposited after the onset of subduction this syncollisional sample shows two distinct u pb age peaks at c 290 ma and 305 ma this points to a few sources only patagonia west antarctica initial hf isotope compositions of selected u pb dated zircons from the carboniferous metasediments reveal zircon protoliths originating from both recycled crust and juvenile sources ehf t 0 4 3 5ga 14 to 12 a comparison with crustal compositions of possible source areas indicates that the detritus mainly originated from the interior of gondwana extra andean patagonia the argentine sierra de la ventana southernmost africa east antarctica as well as northern chile and northwestern argentina the sediment transportation paths are consistent with an autochthonous palaeogeographical position of patagonia with respect to gondwana in carboniferous time

rb sr dating of differentiated cleavage from the upper adelaidean metasediments at hallett cove southern adelaide fold belt abstract upper adelaidean psammites from the foreland part of the late proterozoic adelaide fold belt at hallett cove have suffered one major deformation which produced upright folds that plunge gently south axial to these folds is a well developed differentiation cleavage inferred to have resulted from constant volume plane strain deformation by solution transfer and now defined by alternating p phyllosilicate rich and q quartz rich domains geochemical analyses show that cleavage development resulted in a 2 4 fold fractionation of rb sr between the p and q domains thus the age of deformation is datable and isotopic analyses show the p and q domains form a 531 32 ma isochron this age is statistically older than the pervasive deformation and metamorphism in the more interior parts of the fold belt inferred from intrusive ages to have occurred at 485 6 ma and thus suggests that deformation either propagated across the fold belt from external to interior zones or that it occurred episodically the age data allow but do not demand that cleavage formation predated the deposition of the overlying cambrian kanmantoo group sediments

the allochthony of the argentine precordillera ten years later 1993 2003 a new paleobiogeographic test of the microcontinental model abstract recent and new faunal data from the cambrian to silurian rocks of the precordillera famatina and northwest argentina basins are used to discriminate between different paleogeographic models and especially to establish to what extent they are compatible with a previous conclusion that the precordillera is a laurentian derived microcontinent there is no paleontological evidence to support a para autochthonous gondwanan origin of the precordillera the strong differences in the cambrian trilobite faunas and lithologic successions preclude a common origin of the precordillera terrane eastern antarctica and south africa recent discoveries of brachiopods and organisms of the phylum agmata strengthened laurentian affinities during the cambrian the latest cambrian early ordovician faunas that inhabited the autochthonous northwest argentina basin including the western puna volcaniclastic successions are mostly peri gondwanan the early ordovician brachiopods ostracods and trilobites display mixed laurentian baltic and avalonian biogeographical links supporting a drifting of the precordillera across the iapetus ocean increasing gondwanan elements during the llanvirn along with varied geological evidence indicate that the first stages of collision may have begun at that time involving a major change in the plate kinematics the distribution of facies and faunas basin development and timing of deformation are interpreted as resulting from a north to south diachronous closing of the remnant basin during the last phases of convergence and oblique collision of the precordillera terrane with the gondwana margin the high level of endemism of caradoc faunas may be a consequence of the rearrangement and partial isolation of sedimentary areas during the strike slip movement of the colliding precordillera plate with respect to the gondwana margin suggested relationships between facies distribution geographic barriers and faunal migrations before and during the collision are depicted in a series of schematic reconstructions at five time slices from late cambrian to silurian

contribution from multiple fault ruptures to tsunami generation during the 2016 kaikoura earthquake the 2016 kaikoura new zealand earthquake was one of the most complex ruptures ever recorded the epicentre was located well inland but the rupture area extended offshore and generated a modest tsunami which was recorded by tide gauges here we present a detailed estimate of seafloor vertical displacement during the earthquake sequence by a joint inversion of tsunami waveforms and vertical displacement data observed at gps stations and obtained by field surveys the combined dataset provides a solution with good resolution capable of resolving test sources of 20 km of characteristic diameter throughout the study area we found two seafloor uplift regions which are located very close to the coast one is located offshore of the kaikoura peninsula and the other larger uplift region is located near the kekerengu and needles faults to estimate crustal deformation with a complete spatial coverage of the event the estimated seafloor vertical displacement was combined with the inland vertical displacement from insar and gps datasets this vertical displacement is then inverted for the fault slip distributions of the needles jordan kekerengu papatea hundalee hump faults and a newly identified fault beneath kaikoura we also found that the needles fault is probably an offshore extension of the kekerengu fault the seismic moment calculated from the fault slip distributions by assuming a rigidity of 2 7 1010 n m2 is 5 19 1020 nm or equivalent to mw 7 8 this total seismic moment estimate is consistent with that of the global centroid moment tensor solution the tsunami potential energy calculated from the seafloor vertical displacement is 9 40 1012 j of which about 70 is attributed to movement on the faults known to have ruptured suggesting a secondary source for tsunami generation