surface wave tomography of the western united states from ambient seismic noise rayleigh and love wave phase velocity maps summary we present the results of rayleigh wave and love wave phase velocity tomography in the western united states using ambient seismic noise observed at over 250 broad band stations from the earthscope usarray transportable array and regional networks all available threecomponent time series for the 12 month span between 2005 november 1 and 2006 october 31 have been cross correlated to yield estimated empirical rayleigh and love wave green s functions the love wave signals were observed with higher average signal to noise ratio snr than rayleigh wave signals and hence cannot be fully explained by the scattering of rayleigh waves phase velocity dispersion curves for both rayleigh and love waves between 5 and 40 speriod were measured for each interstation path by applying frequency time analysis the average uncertainty and systematic bias of the measurements are estimated using a method based on analysing thousands of nearly linearly aligned station triplets we find that empirical green s functions can be estimated accurately from the negative time derivative of the symmetric component ambient noise cross correlation without explicit knowledge of the source distribution the average traveltime uncertainty is less than 1 s at periods shorter than 24 s we present rayleigh and love wave phase speed maps at periods of 8 12 16 and 20 s the maps show clear correlations with major geological structures and qualitative agreement with previous results based on rayleigh wave group speeds

global positioning system measurements of present day crustal movements in the arabia africa eurasia plate collision zone we present and interpret global positioning system gps measurements of crustal motions for the period 1988 1994 at 54 sites extending east west from the caucasus mountains of southern russia georgia and armenia to the aegean coast of turkey and north south from the southern edge of the eurasian plate pontus block to the northern edge of the arabian platform viewed from a eurasia fixed reference frame sites on the northern arabian platform move n38 13 w at 20 3 mm yr roughly consistent with the velocity implied by nuvel 1a circuit closure n23 7 w at 24 2 mm yr the motion of arabia appears to be transferred directly to the region of turkey north of the suture however eastern turkey is characterized by distributed deformation while central western turkey is characterized by coherent plate motion involving westward displacement and counterclockwise rotation of the anatolian plate internal deformation within the central part of the anatolian plate is less than 2 mm yr the anatolian plate is decoupled from eurasia along the right lateral strike slip north anatolian fault naf this different response in eastern and western turkey to the collision of arabia may result from the different boundary conditions the hellenic arc forming a free boundary to the west and the asian continent and oceanic lithosphere of the black and caspian seas forming a resistant boundary to the north and east we derive a best fitting euler vector for anatolia eurasia motion of 29 2 0 8 n 32 9 0 4 1 3 0 1 m y the mapped surface trace of the naf corresponds well to a small circle about this pole the new euler vector implies an upper bound for naf slip rate of 30 2 mm yr i e assuming all relative motion is accommodated along the naf using the nuvel 1a euler vector for arabia eurasia and the gps euler vector for anatolia eurasia we determine an arabia anatolia euler vector of 31 2 n 45 2 e 0 9 0 1 m y and an upper bound on the east anatolian fault slip rate of 15 3 mm yr the aegean trough region of western turkey deviates significantly from coherent plate rotation in addition to rotating with anatolia this region shows roughly n s extension at a rate of 14 5 mm yr taken together with satellite laser ranging results along the hellenic arc the contemporary pattern of deformation indicates increasing motions toward the arc suggesting that the westward displacement and counterclockwise rotation of anatolia is driven both by pushing from the arabian plate and by pulling or basal drag associated with the foundering african plate along the hellenic subduction zone

building 3d shear wave velocity models using surface waves testing the tarcento basin case history the paper reports on the use of surface wave testing for the construction of a three dimensional 3d shear wave velocity model of an alluvial basin the town of tarcento italy is located in a region with a high level of seismic hazard and was strongly affected by the two friuli earthquakes in 1976 the seismic surveys were performed with surface wave multistation methods using a combination of active source and passive source experimental setup experimental data were collected at 16 sites and inversion of the data is based on an innovative procedure for spatially constrained inversion with a single objective function in which a priori information is included the method provides an improvement in the robustness of the solution mitigating solution nonuniqueness available borehole logs at different locations are integrated into the data set in terms of a priori bedrock information three independent cross hole tests are used for a posteriori comparison of the inverted one dimensional 1d profiles three dimensional interpolation of the obtained profiles leads to a shear wave velocity model that is internally consistent and complies with a priori information cross hole results and suitable boundary profiles the model is intended for numerical simulations of the seismic response of the basin online material figure showing the a priori bedrock surface

geomorphology and natural hazards in karst areas a review 1 introductionsince human beings started to colonise the world slowly migrat ing in multiple directions from the african rift and ultimatelyreaching the southernmost territories of the americas they haveinteracted with the natural environment using its resources and suf fering from its hazardous processes survival of mankind was possiblethanks to its ability to adapt to an ever changing environment and itscapability to learn and communicate the new ndings from the ear liest times geomorphic features and processes were an essential partof social survival crozier et al 2011 in karst terrains caves wereused as shelters as well as burial and sacred places playing an instru mental role in the day to day struggle for survival especially duringthe ice ages fig 1 spectacular karst landmarks such as big cave en trances blue karst springs deep collapse sinkholes cenotes or rockarches just to name a few have often become part of the naturaland supernatural heritage of our ancestors in prehistoric times the human impact on the karst environmentwas very limited like the probability of properties and people beingdamaged by karst processes e g subsidence ooding both impactsandhazardsinkarstterrainshaveincreaseddramaticallyover thelasttwo centuries along with the exponential increase in population andour capability to modify the natural environment largely related tothe economic and technological development of the societies an in creasing number of scientists consider that humans are nowadaysthe most effective geomorphic agent and a prime factor in landscapeevolution zalasiewicz et al 2010 price et al 2011 in fact the for mal de nition of the anthropocene as a new epoch of the geologicaltime scale characterised by a signi cant and global human impact onthe earth s ecosystems is being debated at the present time around25 of the earth s population lives on or nearby karst areas ford andwilliams 2007 and the increasing exploitation of karst resources such as water and building material is leading to severe environmen tal impacts and unsustainable situations drew and hotzl 1999 gunn 2004 unfortunately the number of karst areas affected bywater pollution landscape degradation and other impacts is growingveryrapidly additionally thedamagecausedbyhazardouskarstpro cesses especially subsidence sinkholes beck 2003 waltham et al 2005 gutierrez et al 2008a will most likely keep on increasing exposed human elements augment and anthropogenic changes inthe karst systems frequently result in hazard enhancement karstgeomorphologists and hydrologists can play a decisive role in pre venting natural disasters in karst areas particularly those inducedby human activities dams with leakage and sinkhole problems milanovic 2000 cooper and gutierrez 2011 mines and tunnelsaffected by ooding and subsidence li and zhou 1999 autin 2002 casagrandeet al 2005 luchaetal 2008 high speedrailwaysbuilt in sinkhole prone areas guerrero et al 2008 or developmentof sinkholes at huge rates induced by lake level yechieli et al 2006 or water table sprynskyy et al 2009 declines the importance of properly managing karst areas and mitigatingthe detrimental effects caused by human activities on these inherentlysensitive environments has been boosted by a series of conferencesand projects since the early 1990s ford 1993 williams 1993 pariseet al 2008 2009 raising public awareness on the need to protectour endangered natural resources especially in developed countries has promoted the production of karst speci c environmental impactassessments veni 1999 recently severalapproacheshavebeenpro posedtoassessthedegreeofhuman induceddisturbanceinkarstareas van beynen and townsend 2005 calo and parise 2006 de waele 2009 north et al 2009 although these studies are essential for apropermanagementofthekarstresources theymaybefutileifnotfol lowed by adequate administrative decisions and regulations 2 karst geomorphology2 1 karst processeskarst is characterised by the predominance of rock dissolution overmechanical erosion and is typical of present temperate cold andwarm and tropical environments ford and williams 2007 in karstterrains surface and subsurface geomorphology and hydrology arelargely governed by dissolution of carbonate and or evaporite rocks in the most classical common situation surface waters acidi ed byco

a new look at the structural geology of the southern side of the central and eastern high atlas mountains we give a general description of two evaporite basins discovered one under and the other south of the lower jurassic carbonate platform which fringes the atlas gulf in the south the larger of these basins lies in the triangle tazzouguert aoufouss tarda the smaller whose extent is difficult to determine it being considerably deformed and partially covered over by the southward sliding of the liassic carbonate platform lies north of tinerhir and ifer marl and evaporite middle liassic deposits from this smaller basin form a tectonic window in the massive limestones of the liassic carbonate platform at tisgui todrha gorges this window clearly shows that the zone in question was affected by southward sliding to the east of tazzouguert going towards bouanane the carbonate platform backs directly onto the african craton

segmented african lithosphere beneath the anatolian region inferred from teleseismic p wave tomography summary lithospheric deformation throughout anatolia a part of the alpine himalayan orogenic belt is controlled mainly by collision related tectonic escape of the anatolian plate and subduction roll back along the aegean subduction zone we study the deeper lithosphere and mantle structure of anatolia using teleseismic finite frequency p wave traveltime tomography we use data from several temporary and permanent seismic networks deployed in the region approximately 34 000 p wave relative traveltime residuals measured in multiple frequency bands are inverted using approximate finite frequency sensitivity kernels our tomograms reveal segmented fast seismic anomalies beneath anatolia that corresponds to the subducted portion of the african lithosphere along the cyprean and the aegean trenches we identify these anomalies as the subducted aegean and the cyprus slabs that are separated from each other by a gap as wide as 300 km beneath western anatolia this gap is occupied by slow velocity perturbations that we interpret as hot upwelling asthenosphere the eastern termination of the subducting african lithosphere is located near the transition from central anatolia to the eastern anatolian plateau or arabian eurasian collision front that is underlain by large volumes of hot underplating asthenosphere marked by slow velocity perturbations our tomograms also show fast velocity perturbations at shallow depths beneath northwestern anatolia that sharply terminates towards the south at the north anatolian fault zone nafz the associated velocity contrast across the nafz persists down to a depth of 100 150 km hence our study is the first to investigate and interpret the vertical extent of deformation along this nascent transform plate boundary overall the resolved upper mantle structure of anatolia is directly related with the geology and tectonic features observed at the surface of the anatolian plate and suggest that the segmented nature of the subducted african lithosphere plays an important role in the evolution of anatolia and distribution of its tectonic provinces

the hydrogeology of high mountain carbonate areas an example of some alpine systems in southern piedmont italy the hydrogeological characteristics of some springs supplied by high mountain carbonate rock aquifers located in the south of piedmont in italy are presented in this work the aquifers have different geological structural conditions including both deep and superficial karstification their catchment areas are located in a typical alpine context at a high altitude of about 2000 m these aquifers are ideal representations of the different hydrogeological situations that can be encountered in the high altitude carbonate aquifers of the mediterranean basin it is first shown how the high altitude zones present typical situations in particular related to the climate which control the infiltration processes to a great extent snowfall accumulates on the ground from november to april often reaching remarkable thicknesses the snow usually begins to melt in spring and continues to feed the aquifer for several months this type of recharge is characterized by continuous daily variations caused by the typical thermal excursions the hourly values are somewhat modest but snowmelt lasts for a long time beginning in the lower sectors and ending after various months in the higher areas abundant rainfall also occurs in the same period and this contributes further to the aquifer supply in the summer period there is very little rainfall but frequent storms in autumn abundant rainfall occurs and there are therefore short but relevant recharge events it has been shown how the trend of the yearly flow of the high mountain springs is influenced to a great extent by the snowmelt processes and autumn rainfall it has also been shown by means of the annual hydrographs of the flow and the electric conductivity of the spring water how the different examined aquifers are characterized by very different measured value trends according to the characteristics of the aquifer

3 d crustal structure along the north anatolian fault zone in north central anatolia revealed by local earthquake tomography summary 3 d p wave velocity structure and vp vs variations in the crust along the north anatolian fault zone nafz in north central anatolia were investigated by the inversion of local p and s wave traveltimes to gain a better understanding of the seismological characteristics of the region the 3 d local earthquake tomography inversions included 5444 p and 3200 s wave readings obtained from 168 well located earthquakes between 2006 january and 2008 may dense ray coverage yields good resolution particularly in the central part of the study area the 3 d vp and vp vs tomographic images reveal clear correlations with both the surface geology and significant tectonic units in the region we observed the lower limit of the seismogenic zone for north central anatolia at 15 km depth final earthquake locations display a distributed pattern throughout the study area with most of the earthquakes occurring on the major splays of the nafz rather than its master strand we identify three major high velocity blocks in the mid crust separated by the izmir ankara erzincan suture and interpret these blocks to be continental basement fragments that were accreted onto the margin following the closure of neo tethyan ocean these basement blocks may have in part influenced the rupture propagations of the historical 1939 1942 and 1943 earthquakes in addition large variations in the vp vs ratio in the mid crust were observed and have been correlated with the varying fluid contents of the existing lithologies and related tectonic structures

seismic velocity and poisson s ratio tomography of the crust beneath east anatolia abstract eastern anatolia is a region in the early stages of continent continent collision and so provides a unique opportunity to study the early development of continental plateau located within the alpine himalayan fold thrust fault belt the anatolian plateau is geologically very complex with over half of the surface area covered with late cenozoic volcanics of diverse composition the plateau is also seismically active and is dissected by numerous seismogenic faults predominantly of strike slip motion in this study we determine 3 d tomographic images of the crust beneath eastern anatolia by inverting a large number of arrival time data of p and s waves from the obtained p and s wave velocity models we estimated the poisson s ratio structures for a more reliable interpretation of the obtained velocity anomalies our tomographic results are generally consistent with the major tectonic features of the region high p and s wave velocity anomalies are recognized near the surface while at deeper crustal layers low seismic wave velocities are widely distributed poisson s ratio exhibits significant structural heterogeneities compared to the imaged velocity structure the seismic activity is intense along highly heterogeneous zones and is closely associated with pre existing faults in the central and western parts of the study area results of the checkerboard resolution test indicate that the imaged anomalies are reliable features down to a depth of about 40 km the low velocity high poisson s ratio zones in the middle to lower crust are consistent with many geophysical observations such as strong sn attenuation low pn and sn velocity and the absence of mantle lid implying the presence of partial melt in the uppermost mantle

joint inversion of body wave arrival times and surface wave dispersion for three dimensional seismic structure around safod we incorporate body wave arrival time and surface wave dispersion data into a joint inversion for three dimensional p wave and s wave velocity structure of the crust surrounding the site of the san andreas fault observatory at depth the contributions of the two data types to the inversion are controlled by the relative weighting of the respective equations we find that the trade off between fitting the two data types controlled by the weighting defines a clear optimal solution varying the weighting away from the optimal point leads to sharp increases in misfit for one data type with only modest reduction in misfit for the other data type all the acceptable solutions yield structures with similar primary features but the smaller scale features change substantially when there is a lower relative weight on the surface wave data it appears that the solution over fits the body wave data leading to a relatively rough vs model whereas for the optimal weighting we obtain a relatively smooth model that is able to fit both the body wave and surface wave observations adequately

active tectonics of the north and central aegean sea summary in this paper we examine the connection between the westward motion of turkey relative to europe and the extension in and around the aegean sea the principal new data available since the last attempt to synthesize the tectonics of this region by mckenzie 1978 are much improved focal mechanisms of earthquakes constrained by p and sh body wave modelling as well as by first motions these mechanisms show that the faulting in the western part of the aegean region is mostly extensional in nature on normal faults with a nw to wnw strike and with slip vectors directed nnw to nne there is evidence from palaeomagnetism that this western region rotates clockwise relative to stable europe in the central and eastern aegean and in nw turkey distributed right lateral strike slip is more prevalent on faults trending ne to ene and with slip vectors directed ne palaeomagnetic data in this eastern region is more ambiguous but consistent with very small or no rotations in the northern part and possibly anticlockwise rotations relative to europe in the south the strike slip faulting that enters the central aegean from the east appears to end abruptly in the sw against the nw trending normal faults of greece the kinematics of the deformation is controlled by three factors the westward motion of turkey relative to europe the continental collision between nw greece albania and the apulia adriatic platform in the west and the presence of the hellenic subduction zone to the south as the right lateral slip on the north anatolian fault enters the aegean region it splays out becoming distributed on several parallel faults the continental shortening in nw greece and albania does not allow the rotation of the western margin of the region to be rapid enough to accommodate this distributed e w right lateral shear and thus leads to e w shortening in the northern aegean which is compensated by n s extension as the southern aegean margin can move easily over the hellenic subduction zone the dynamics of the system once initiated is self sustaining being driven by the high topography in eastern turkey and by the roll back of the subducted slab beneath the southern aegean the geometry of the deformation resembles the behaviour of a system of broken slats attached to margins that rotate in spite of its extreme simplicity a simple model of such broken slats is able to reproduce quantitatively most of the features of the instantaneous velocity field in the aegean region including the slip vectors and nature of the faulting in the eastern and western parts the senses and approximate rates of rotation the overall extensional velocity across the aegean and the distribution of strain rates as seen in the seismicity and topography or bathymetry and using geodetic measurements as part of this study we re examined the relation between the surface faulting and the focal parameters determined seismologically for the three large 1981 gulf of corinth earthquakes and reassessed the evidence for associating particular earthquakes in the sequence with observed surface faulting an important result is that in one of the events there is a resolvable discrepancy between the slip vector measured at the surface and that determined from the seismic body waves

focused groundwater flow in a carbonate aquifer in a semi arid environment summary an efficient conveyance system for groundwater is shown to have formed in a carbonate aquifer even though it is situated in a semi arid environment this conveyance system comprises preferential flow pathways that developed coincident with river channels a strong correlation between high capacity wells and proximity to higher order river channels i e within 2 5 km is used as evidence of preferential flow pathways factors that contributed to development of the preferential flow paths i karst development in carbonate rocks ii structural exhumation of a carbonate plateau and iii the requirement that the groundwater regime of the watershed has adequate capacity to convey sufficient quantities of water at the required rates across the full extent of the watershed recognition of these preferential pathways in proximity to river channels provides a basis to locate where high capacity wells are likely and unlikely and indicates that groundwater flow within the watershed is relatively rapid consistent with flow rates representative of karstic aquifers this understanding provides a basis for better informed decisions regarding water resource management of a carbonate aquifer in a semi arid environment

a relict paleoseismic record of seven earthquakes between 2000 b c and 600 a d on the central north anatolian fault at elmacik near osmancik turkey deformation along the northern edge of the westward moving anatolian plate is concentrated along the north anatolian fault this northward arching fault extends from the karliova triple junction in the east 1500 km into the aegean sea in the west a sequence of twentieth century earthquakes ruptured the fault displaying a spatiotemporal pattern consistent with a stress triggering mechanism in 1943 the m w 7 6 tosya earthquake ruptured a 280 km long segment near the center of the fault four paleoseismic investigations have previously investigated this segment and the present study was conducted near its center in an 180 km long gap between existing studies a paleoseismic trench revealed a sequence of eight sediment packages abutting a highly developed shear zone each of the packages consists of a fine grained layer overlying a coarse grained layer based on correlation between the age of the base of the coarse grained layers and existing earthquake records we infer that the coarse grained layers were deposited in response to earthquakes because of increased erosion on an adjacent steep slope the most recent event horizon may correlate to the historical 529 a d earthquake timing of six older earthquakes is constrained to 2s 23 b c 103 a d 609 185 b c 971 814 b c 1227 968 b c 2050 1777 b c and 2556 2235 b c which correspond to a summed interevent time of 97 912 yr 2s the earthquake record is relict because the local stream network was incised ca 1000 a d isolating the trench site from its sediment source a stream near the trench was subsequently offset by 23 5 1 5 m yielding a right lateral slip rate of 21 4 25 6 mm yr and suggesting that the 1943 rupture caused an uncharacteristically small offset

late cenozoic evolution of the ariege river valley pyrenees constrained by cosmogenic 26al 10be and 10be 21ne dating of cave sediments abstract despite increasing knowledge on the orogenic phases of the pyrenees the neogene evolution of the range remains poorly constrained the central pyrenees particularly the ariege river valley and its terrace systems and glacial extensions are key to reconstructing pyrenean evolution during the neogene however few terrace relics remain on the piedmont edges to overcome this limitation and temporally extend the dataset obtained from terraces we focus on alluvium filled horizontal epiphreatic passages developed in limestone karstic networks these landforms record the transient position of former local base levels during the process of valley deepening similar to fluvial terraces the alluvium fills of the studied caves in the tarascon sur ariege area in the transition zone between the upper range and the piedmont therefore enable the reconstruction of the geodynamic evolution of the ariege river valley all studied caves are developed on at least eight levels based on burial durations determined by 26al 10be and 10be 21ne terrestrial cosmogenic nuclide dating of samples from epiphreatic levels our results indicate langhian to messinian 13 5 ma incision rates averaging 48 m myr 1 however the obtained record does not allow us to accurately retrace the pliocene evolution of the area due to the lack of known caves at corresponding levels moreover raised local base levels during glacial phases both make the record more complex and call into question the methodological approach in terms of potential internal sediment remobilization and mixing related to implied re flooding periods

development of pull apart basins a comparative study of well mapped active and ancient pull apart basins suggests a qualitative model for their continuous development pull aparts evolve from incipient to extremely developed basins through a sequence of closely related states new and compiled map data from several areas including the northern caribbean and turkey suggests the following stages in pull apart development 1 in rigid intracontinental strike slip plate boundary zones larger pull aparts nucleate at releasing fault bends along segments of the principal displacement strike slip fault zone which are oblique to the theoretical interplate slip lines 2 initial opening across releasing fault bends produces spindle shaped basins defined and often bisected by oblique slip faults connecting the discontinuous ends of the strike slip faults 3 increased strike slip offset produces basin shapes which we colloquially call lazy s shape for basins between sinistral faults and lazy z shape for basins between dextral faults 4

new kinematic and geochronologic evidence for the quaternary evolution of the central anatolian fault zone cafz as the kinematics of active faults that bound the anatolian plate are well studied it is now essential to improve our understanding of the style and rates of intraplate deformation to constrain regional strain partitioning and improve seismic risk assessments one of these internal structures the central anatolian fault zone cafz was originally defined as a regionally significant left lateral tectonic escape structure stretching for 700 km in a ne direction across the anatolian plate we provide new structural geomorphic and geochronologic data for several key segments within the central part of the cafz that suggest that the sinistral motion has been overstated the ecemis fault the southernmost part of the cafz has a late quaternary minimum slip rate of 1 1 0 4 mm a 1 slower than originally proposed farther north the erciyes fault has fed a linear array of monogenetic vents of the erciyes stratovolcano and 40ar 39ar dating shows a syneruptive stress field of ese wnw extension from 580 130 ka to 210 180 ka in the erciyes basin and central part of the cafz we mapped and recharacterized the erkilet and gesi faults as predominantly extensional these long term geological rates support recent gps observations that reveal ese wnw extension which we propose as the driver of faulting since 2 73 0 08 ma the slip rates and kinematics derived in this study are not typical of an escape tectonic structure the cafz is a transtensional fault system that reactivates paleotectonic structures and accommodates e w extension associated with the westward movement of anatolia

role of sediment in speleogenesis sedimentation and paragenesis although the effects of sedimentation in caves have been recognised for many years its role in speleogenesis is frequently overlooked influxes of sediment into a cave system fundamentally alter the way cave passages develop either by alluviation in a vadose environment forcing lateral corrosion and the development of notches or by upwards dissolution in a phreatic environment through a process known as paragenesis sediment influxes affect the hydrological functioning of a karst aquifer by changing the way conduits behave and subsequently develop both in plan and long section here we give an overview of the mechanisms of cave sedimentation and describe how the process of alluviation and paragenesis affect speleogenesis a characteristic suite of meso and micro scale dissolutional features can be used to recognise paragenetic development which is reviewed here in a vadose environment these include alluvial notches whilst in a phreatic environment half tubes anastomoses and pendants bedrock fins and paragenetic dissolution ramps result using these to identify phases of sedimentation and paragenesis is crucial for reconstructing denudation chronologies from cave deposits we suggest that sedimentation and paragenesis are most likely to occur in certain geomorphological situations such as ice marginal and periglacial environments beneath thick residual soils and where rivers can transport fluvial sediment into a cave either via stream sinks or back flooding

empirical correlations of shear wave velocity vs and penetration resistance spt n for different soils in an earthquake prone area erbaa turkey abstract the seismicity of the northern part of turkey is mainly controlled by the north anatolian fault zone nafz the nafz is one of the world s most active seismic zones and has produced destructive earthquakes and related hazards in the northern region of turkey several earthquakes and earthquake related hazards have occurred along different segments of this fault zone in the recent past the study area erbaa town is located along the eastern segment of north anatolian fault zone nafz and is one of the largest towns of tokat province in the middle black sea region of turkey the center of erbaa is located on the left embankment of the kelkit river after the disastrous 1942 ms 7 2 and 1943 ms 7 6 earthquakes the settlement was shifted southwards as a part of a seismic microzonation study of the erbaa area shear wave velocity vs values of the geological units exposed in this area were required for site response analyses the geological units in the study area consist mainly of alluvial and pliocene units these layers were evaluated on the basis of drilling in situ spt scptu and spt based uphole and laboratory testing in this study empirical correlations between shear wave velocity vs and standard penetration test blow counts spt n were considered in order to define shear wave velocity profiles for the study area the relationships between shear wave velocity standard penetration test spt blow counts and the soil properties were evaluated as functions of depth spt based uphole tests were performed to measure shear wave velocity during drilling operations in some of the borings the spt based vs values were computed with different empirical formulas and compared with the measured spt based uphole vs measurements the empirical correlations were found to require modification to provide the best correlation for this site the depth factor was considered during the development of new empirical equations therefore a site specific formula was proposed in order to obtain vs profiles for all layers in the study area

analysis of the north anatolian shear zone in central pontides northern turkey insight for geometries and kinematics of deformation structures in a transpressional zone abstract the western part of the north anatolian shear zone at the southern boundary of the central pontides in turkey was investigated in the kursunlu arac area by means of a geological structural field study in this area the north anatolian shear zone results in a transpressional deformation zone that extends between two master faults striking parallel to the main shear direction the main systems of structures identified in the deformation zone appear to be oriented parallel to the directions predicted by riedel theoretical model nevertheless the strain partitioning is more complicated than predicted by theory the structural analysis suggests a polyphase deformation characterized by a steady component of transcurrence associated with alternance of compression and extension along each of theoretical directions the combination of double verging structures can be observed with folds and thrust surfaces root into high angle shear zones according to flower type geometries the discrepancies of directions kinematics and geometries from theoretical models are due to transpressive and or transtensive nature of the deformation according to the observed outcropping structures we propose a conceptual model for the north anatolian shear zone interpreting it as a crustal scale positive flower structure

field investigation of love waves in near surface seismology we examine subsurface conditions and survey parameters suitable for successful exploitation of love waves in nearsurface investigations love wave generation requires the existence of a low shear velocity surface layer we examined the minimum thickness of the near surface layer necessary to generate and record usable love wave data sets in the frequency range of 5 50 hz we acquired field data on a hillside with flat lying limestone and shale layers that allowed for the direct testing of varying overburden thicknesses as well as varying acquisition geometry the resulting seismic records and dispersion images were analyzed and the love wave dispersion relation for two layers was examined analytically we concluded through theoretical and field data analysis that a minimum thickness of 1 m of low velocity material is needed to record usable data in the frequency range of interest in near surface love wave surveys the results of this study indicate that existing guidelines for rayleigh wave data acquisition such as receiver interval and line length are also applicable to love wave data acquisition

a 3000 year record of ground rupturing earthquakes along the central north anatolian fault near lake ladik turkey the north anatolian fault naf is a similar to 1500 km long arcuate dextral strike slip fault zone in northern turkey that extends from the karliova triple junction to the aegean sea east of bolu the fault zone exhibits evidence of a sequence of large m w 7 earthquakes that occurred during the twentieth century that displayed a migrating earthquake sequence from east to west prolonged human occupation in this region provides an extensive but not exhaustive historical record of large earthquakes prior to the twentieth century that covers much of the last 2000 yr in this study we extend our knowledge of rupture events in the region by evaluating the stratigraphy and chronology of sediments exposed in a paleoseismic trench across a splay of the naf at destek similar to 6 5 km east of lake ladik 40 868 degrees n 36 121 degrees e the trenched fault strand forms an uphill facing scarp and associated sediment trap below a small catchment area the trench exposed a narrow fault zone that has juxtaposed a sequence of weakly defined paleosols interbedded with colluvium against highly fractured bedrock we mapped magnetic susceptibility variations on the trench walls and found evidence for multiple visually unrecognized colluvial wedges this technique was also used to constrain a predominantly dip slip style of displacement on this fault splay sediments exposed in the trench were dated using both charcoal and terrestrial gastropod shells to constrain the timing of the earthquake events while the gastropod shells consistently yielded 14 c ages that were too old by similar to 900 yr we obtained highly reliable 14 c ages from the charcoal by dating multiple components of the sample material our radiocarbon chronology constrains the timing of seven large earthquakes over the past 3000 yr prior to the 1943 tosya earthquake including event ages of 2 sigma error a d 1437 1788 a d 1034 1321 a d 549 719 a d 17 585 1 3 events 35 b c a d 28 700 392 b c 912 596 b c our results indicate an average interevent time of 385 166 degrees yr 1 sigma

provenance study of endokarst fine sediments through mineralogical and geochemical data lezetxiki ii cave northern iberia abstract the characteristics and provenance of the fine sediment forming the matrix of detrital endokarst fill can vary greatly and their study provides valuable information about the paleoenvironment and the different sedimentary and diagenetic processes in which it was formed and deposited this paper applies this study to the case of lezetxiki ii cave arrasate gipuzkoa using x ray diffraction xrd x ray fluorescence xrf and scanning electron microscopy sem eds analysis with samples of endokarst sediment rocks and soils in the surroundings of the cave the following source areas and sedimentary processes have been identified 1 allochthonous sedimentation through the fluviokarst processes which eroded soils formed on siliciclastic formations it is characterised by a high percentage of illite in the sediment and predominated in relatively cold periods in mis 6 and mis 2 4 2 sedimentation through infiltration from karst fissures of the autochthonous soils formed on the limestone substrate terra rossa it is characterised by a higher vermiculite content and prevailed in the warm mis 5 period and the holocene 3 chemical sedimentation where calcite precipitated in the form of speleothems in warmer and more humid periods and 4 deposition of microfauna bones in owl pellets

relationships between fluvial evolution and karstification related to climatic tectonic and eustatic forcing in temperate regions this paper reviews the diversity of relationships between river evolution and karstogenesis it also underlines the fundamental role of numerical dating methods e g cosmogenic nuclides applied to sedimentary sequences in tiered cave passages as they have provided new insights into these complex interactions although karst terrain is widespread worldwide we focus on european karst catchments where the sedimentary records are especially well preserved we review the recent dating of fluvial sediments and speleothems to examine the timing of karstification incision and deposition in cave levels the most complete alluvial records occur in tectonically uplifted high mountains where some of the oldest sediment fills date to the miocene evidence indicates that not only uplift but also climatic conditions and fluvial dynamics e g knickpoint retreat increased channel flow and or sediment load and stream piracies can play a major role in speleogenesis and geomorphological evolution in evaporite rocks speleogenesis is characterized by rapid dissolution and subsidence in european catchments gypsum cave development largely occurred during cold climate periods while limestone caves formed during warm interglacial or interstadial phases our synthesis is used to propose four models of fluvial and karst evolution and highlight perspectives for further research

slip distribution along the north anatolian fault associated with the large earthquakes of the period 1939 to 1967 abstract between 1939 and 1967 six large fault ruptures formed a westward migrating sequence of events along a 900 km long nearly continuous portion of the north anatolian fault for these events the 1939 erzincan 1942 niksar erbaa 1943 tosya 1944 bolu gerede 1957 abant and 1967 mudurnu valley earthquakes i have compiled a record of dextral slip which contains nearly 100 points these data indicate that the amount of slip is irregularly distributed along the 1939 to 1967 rupture zone the maximum slip 7 5 m occurred during the 1939 earthquake in the eastern 150 km of the 900 km long rupture zone dextral offsets diminish very abruptly eastward but very gradually westward the rate of westward decrease in the 1939 to 1967 offsets is only slightly greater than the rate of westward decrease of post miocene displacement along the north anatolian fault this suggests that westward decrease in slip can be expected to be a general characteristic of earthquake ruptures along the north anatolian fault in the future nevertheless within the 1939 to 1967 slip distribution there are three regions that had less slip than the neighboring regions these i interpret as possible sites of large future earthquakes one of these seismic gaps has already experienced another earthquake in 1951 and subsequent creep

coupling cosmogenic dating and magnetostratigraphy to constrain the chronological evolution of peri mediterranean karsts during the messinian and the pliocene example of ardeche valley southern france the ardeche river entrenches a deep canyon in the saint remeze plateau from vallon pont d arc to its confluence with the rhone this plateau is part of the ardeche cretaceous limestone plateau located at the edge of the mid rhone valley it is characterized by dense multi level cave systems such as saint marcel cave 50 km of mapped passages and chauvet cave famous for its paleolithic paintings until now and despite the absence of absolute dating stepping of the saint remeze cave levels has been interpreted as the result of the messinian salinity crisis to clarify this interpretation fluvial sediments of cave systems have been absolutely dated while cave sediments have been demonstrated to be ideal for burial dating based on the different radioactive decay rates of the in situ produced cosmogenic nuclides 10be and 26al combined with magnetostratigraphy and constrained by the lower ardeche base level curve this contribution provides an absolute dating for each cave level the obtained results are consistent with the stepping per ascensum model of both surface landforms and caves for the messinian pliocene eustatic cycle finally this study provides evidence for a rise of the ardeche river level to 40 m above the pliocene abandonment surface the second active period of the chauvet cave is evidenced between 2 96 and 2 18 ma cave filling an absolute dating for the pliocene abandonment surface between 1 94 and 1 77 ma is also obtained which brings new understandings to the geodynamic evolution of the area the lower ardeche has been uplifted after the pliocene with a rate of 0 03 mm year since 1 77 ma

characterizing an unstable mountain slope using shallow 2d and 3d seismic tomography as transport routes and population centers in mountainous areas expand risks associated with rockfalls and rockslides grow at an alarming rate as a consequence there is an urgent need to delineate mountain slopes susceptible to catastrophic collapse in a safe and noninvasive manner for this purpose we have developed a 3d tomographic seismic refraction technique and applied it to an unstable alpine mountain slope a significant segment of which is moving at 0 01 0 02 m year toward the adjacent valley floor first arrivals recorded across an extensive region of the exposed gneissic rock mass have extraordinarily low apparent velocities at short 0 2 m to long 100 m shot receiver offsets inversion of the first arrival traveltimes produces a 3d tomogram that reveals the presence of a huge volume of very low quality rock with ultralow to very low p wave velocities of 500 2700 m s these values are astonishingly low compared to the average horizontal p wave velocity of 5400 m s determined from labora

susehri basin an active fault wedge basin on the north anatolian fault zone turkey abstract the susehri section of the north anatolian fault zone nafz is dominated by an active fault wedge basin its recent configuration is a quaternary strike slip depression superimposed on a larger fault controlled fluvial to lacustrine setting inherited from the pliocene in and around the susehri fault wedge basin the nafz is characterized by the north anatolian master fault namf or principal displacement zone pdz and four second order fault sets namely the kelkit akcaa il beyde irmeni and ekenek fault sets the namf cuts through the basin the fault sets border the margins of the basin and impart a double divergence character to the namf which is proposed as an evolutionary model for the susehri fault wedge basin the susehri basin fill deposits of pliocene age rest on the quiet and shallow marine limestones of burdigalian age with a sharp angular unconformity besides the upper half of the pliocene basin fill deposits is dominated by the well developed syndepositional mesofractures which reveal the existence of a right lateral shearing at the time of deposition these observations also imply the emergence of a new tectonic regime after the burdigalian by which time the susehri basin had experienced a subsidence of about 660 m to 1150 m during its evolution on the other hand at the south easternmost end of the susehri basin the lutetian volcano sedimentary sequence of the yesilyayla group is cut and displaced right laterally by about 35 km which is the detectable minimum offset on the nafz finally during the 1939 12 27 erzincan earthquake the erzincan erbaa segment of the nafz was reactivated and several modern faults were produced along these modern faults some natural and man made features were displaced right laterally these offsets vary in decreasing order from 7 5 m near the epicenter at the southeastern end to 3 7 m away from it at the northwestern end of the erzincan erbaa segment of the nafz

kinematics of large scale tip line folds from the high atlas thrust belt morocco abstract the kinematics of several tip line folds situated along the south atlas front near goulmima morocco is established using both forward modelling and analysis of syn folding deformation from the sahara foreland to the atlas the two successive major structures forming the mountain front in this area fit geometrically with a generalised fault propagation fold model and a model of fault propagation fold altered by late transport on the upper flat respectively field evidence shows that the two folds are developed more or less synchronously the analysis of minor structures helps address the question of migrating hinges vs fixed hinges during the fold s growth

limited influence of climatic gradients on the denudation of a mediterranean carbonate landscape the dynamics of carbonate dominated landscapes is still debated and first order questions pertaining to the respective importance of chemical and mechanical weathering processes or the influence of climatic variability on denudation rates are largely open to address these issues we investigate the denudation pattern across a climatic gradient in provence se france we focused on a series of major carbonate mountain ranges with elevation spanning 200 to 2000 m and associated with 2 fold variations in mean annual temperature and precipitation we collected 25 samples from 10 different mountain ranges and quantified denudation rates through the measurement of their cl 36 concentrations in order to explore tectonic and climatic controls on these carbonate landscapes evolution we observe that most of our samples experience denudation rates in the 30 60 mm ka range averaged over 5 to 40 ka with no evident dependence on variations of mean annual temperature or precipitation one range lure mountain stands out as a significant outlier with much higher denudation rates 100 mm ka than adjacent sites ventoux mountain at the same elevation and experiencing similar present day environmental conditions we explore in details the climatic tectonic and geomorphological contexts of these two ranges in order to understand the reasons for this apparent 3 fold difference in denudation rates a regionally documented major holocene hillslope destabilization event appears to be a likely candidate to explain the observed lower cl 36 concentrations at the top of the lure mountain at longer wavelengths our regional dataset shows no clear control of modem precipitation gradients on denudation rates consistent with previous observations in landscapes underlain by other lithologies

karst rivers particularity an example from dinaric karst croatia bosnia and herzegovina the very complex system of sinking losing and underground transboundary karst rivers lakes and aquifers in the central part of the deep and bare dinaric karst in croatia and bosnia and herzegovina is analysed the groundwater and surface water are hydraulically connected through numerous karst forms which facilitate the exchange of water between the surface and subsurface a complex underground conduit system is an inherent characteristic karst system analysed groundwater and surface water exchange with both adjacent and distant aquifers through underground routes or inflows from surface streams and artificial reservoirs because of a complex surface and underground karst features which strongly influenced its hydrological and hydrogeological regime the main open stream flow with a longitude of about 106 km undergoes eight name changes in this paper it is noted as the eight name river in fact it represents one river with losing sinking and underground stream sections different surface and underground karst forms play crucial roles in the way the water flowing over the surface and on the underground sections of its catchment the analysed area is full of varied and often spectacular surface landforms including for example the blue and red lakes and the kravice waterfall the analyses made in the paper show the existence of a decreasing trend of mean annual discharges on the eight name river which can cause numerous problems in the regional water resource management of this transboundary river and catchment

multichannel analysis of love waves in a 3d seismic acquisition system abstractmultichannel analysis of love waves malw analyzes high frequency love waves to determine near surface s wave velocities and it is getting increasing attention in the near surface geophysics and geotechnique community based on 2d geometry spread in which sources and receivers are placed along the same line current malw fails to work in a 3d seismic acquisition system this is because love wave particle motion direction is perpendicular to its propagation direction which makes it difficult to record a love wave signal in 3d geometries we have developed a method to perform malw with data acquired in 3d geometry we recorded two orthogonal horizontal components inline and crossline components at each receiver point at the same time by transforming the raw data from rectangular coordinates inline and crossline components to radial transverse coordinates radial and transverse components we recovered love wave data along the transverse direction at each receiver point to achieve a love w

westward propagation of the north anatolian fault into the northern aegean timing and kinematics we present new evidence for the propagation processes of the north anatolian fault folding in the dardanelles straits region allows us to document the timing of the deformation preceding and the finite displacement after the passage of the propagating tip of the fault the accuracy of the observations is due to interplay between deformation and the sea level changes in the mediterranean the well known messinian regression followed by the pliocene transgression the long term kinematics around the sea of marmara pull apart total displacement of about 85 km over the past 5 m y is similar to the present day kinematics deduced from space geodesy at a larger scale westward propagation of the north anatolian fault over nearly 2000 km in the past 10 m y appears to be associated with strain recovery suggesting that the continental lithosphere retains long term elasticity

new evidence of sea level lowstands and paleoenvironment during mis 6 and 4 in the cantabrian coastal karst the cobiheru cave north iberia the geomorphological evolution of the cobiheru cave shows the influence of the non carbonate coastal mountain ranges on coastal karst evolution as well as the temporal distribution of the cold adapted fauna sites in the cantabrian coast geomorphological observation and u th dating lead to the construction of an evolution model the model comprises two episodes of cave deposition occurred at ca 60 70 and 130 150 ka linked to cold climate conditions global sea level lowstands and the erosion of alluvial fans that covered the karst moreover the comparison between the cobiheru record and some raised beaches identified in previous studies sets the beginning of the sea level lowering in the cantabrian sea during the mis 5 4 transition two palaeoenvironments are inferred based on finding equus ferus and elona quimperiana a wet deciduous forest would have been developed on the emerged marine terrace of the cobiheru cave since at least the middle pleistocene and an open landscape with scarce vegetation would have been present at ca 65 ka the erosional event identified in the cobiheru cave helps to understand the temporal distribution of cold adapted mammals located in the asturias region the probable sites of cold adapted fauna developed in caves and alluvial fans would have disappeared after 65 ka therefore palaeontological and palaeoclimate research based on cold adapted mammals suggests the occurrence of an hiatus in the palaeontological record prior to 50 ka this article is protected by copyright all rights reserved

tectonostratigraphic evolution of the basins on the southern branch of the north anatolian fault system in the se marmara region turkey the lithostratigraphy of the mekece iznik corridor the geyve pamukova and the iznik basins on the southern branch of the north anatolian fault system nafs sb was investigated in detail the intra basin deposits carried by sakarya river and the drainage systems in the northern and southern elevated blocks of the iznik and geyve pamukova basins have been classified based on their lithofacies characteristics the geyve pamukova basin which has developed with a nne ssw trending transtensional strain was formed as a lazy z shaped and releasing bend or pure strike slip pull apart basin that is related to simple shear right lateral strike slip faulting the iznik basin was formed by a right lateral strike slip faulting kinematics and nne ssw trending transtension as a result of the step over of the northeast trending dirazali fault from the southern edge to the nw trending gurle fault and the western step over of this fault to the e w trending umurbey fault this strike slip setting is also supported by the nw se trending right lateral oblique normal orhangazi fault on the northern edge of the basin according to this the iznik basin can be described as a more advanced stage of a large scale pull apart basin compared with a lazy z shaped and releasing bend or transtensional strain furthermore it is defined as the former stage of an extreme or rhomboid type transtensional pull apart basin

geodynamic evolution of the peri mediterranean karst during the messinian and the pliocene evidence from the ardeche and rhone valley systems canyons southern france during the messinian pliocene eustatic cycle the mediterranean sea was characterized by a short lived 5 95 5 32 ma sealevel fall which attained 1500 m in some areas the study of benchmark levels permits the chronology and dynamics of this event to be established in the rhone s middle valley our investigations allow a new interpretation for the genesis of the ardeche endokarst a fall in base level was responsible for both the incision of the so called messinian canyons as well as a deep karst development karst systems were formed in association with the messinian canyons of the ardeche and rhone rivers during the flooding of the mediterranean basin 5 32 ma these karst systems were filled by water and plugged by sedimentary infilling of the rias this mechanism pushed groundwater backward through the karst system which in turn formed diagnostic chimney shafts these pathways were geometrically connected to the position of the pliocene benchmark levels consequently the messinian salinity crisis was responsible for two karst responses the first was concomitant with the crisis itself and corresponds to the formation of a karst system the second followed the messinian salinity crisis and corresponds to the adaptation of this karst system in vauclusian karsts by the formation of chimneyshafts

biogenic corrosion caused by bats in drotsky s cave the gcwihaba hills nw botswana abstract located in north west botswana drotsky s cave is a vast cavity hosted within dolomite known for the discovery of archaeological strata dating back to the late stone age it is home to a colony of bats comprising several ten thousands of individuals who are responsible for the accumulation of a thick deposit of guano on which we have conducted research in some of the deeper parts of the cavity a detailed study of the morphologies of the dolomite walls and roofs demonstrates that part of the cave s speleogenesis is probably due to biogenic corrosion this type of weathering and corrosion process is still poorly described in underground environments however it is now accepted that the role played by bats and their droppings on the condition of walls their weathering and the enlargement of galleries and chambers by condensation corrosion processes should be taken into account when considering the way deep networks evolve in this article we discuss the mechanisms of this biogenic corrosion in drotsky s cave as well as their morphogenic impacts the dissolution and recession of walls the formation of lateral notches arches bell holes and ceiling spherical cupolas and the consequences for the wall retreat of conduits finally we propose a new typological classification the consequences of this biogenic corrosion are important for archaeological questions related to the taphonomy of archaeological remains in the buried deposits and the conservation of cave art because of the important impacts of guano on buried biological archaeological remains such a population would have encouraged accelerated weathering corrosion and dissolution of the walls potentially contributing to the total or partial disappearance of any trace of human activity on the surrounding rocks

analog modeling of pull apart basins scaled sandbox models have successfully simulated the geometries and progressive evolution of pull apart basins developed in a weak sedimentary cover above right stepping releasing dextral strike slip fault systems in rigid basement synkinematic basin infill was added progressively as the models were deformed vertical and horizontal sectioning of the completed models has allowed the full three dimensional architecture of the pull apart system to be analyzed we present three representative end member experiments 30 underlapping releasing sidestep 90 sharp nonoverlapping releasing sidestep and 150 overlapping releasing sidestep the pull apart basin geometries are typically sigmoidal to rhombic grabens the geometries of which are dependent upon the architecture of the underlying basement fault systems underlapping releasing sidestepping faults offset angles of 30 75 typically form elongate rhomboidal grabens 90 releasing offset sidesteps produce shorter squat rhomboid pull apart basins and overlapping releasing sidesteps 115 150 produce box like grabens with highly kinked basin sidewalls the pull apart basins are bounded by terraced oblique slip extensional sidewall fault systems that link the laterally offset principal displacement zones pdz of the main dextral strike slip faults the sidewall faults show changes in kinematics from dominantly dip slip extension in copyright 1997 the american association of petroleum geologists all rights reserved 1manuscript received june 24 1996 revised manuscript received november 20 1996 final acceptance june 10 1997 2fault dynamics project geology department royal holloway university of london egham surrey tw20 oex united kingdom supported by the fault dynamics project sponsored by arco british limited petrobras u k ltd bp exploration conoco u k limited mobil north sea limited and sun oil britain we also acknowledge additional funding from sun oil britain landsat thematic mapper data courtesy of rtz mining and exploration limited south american division jurrian reijs is thanked for field data relating to the salina del fraile pull apart basin chris elders is thanked for reviewing earlier versions of this manuscript and j crowell c morley and k biddle are thanked for constructive reviews of the manuscript the contents of this paper have been

delineating a shallow fault zone and dipping bedrock strata using multichannal analysis of surface waves with a land streamer the multichannel analysis of surface waves masw seismic method was used to delineate a fault zone and gently dipping sedimentary bedrock at a site overlain by several meters of regolith seismic data were collected rapidly and inexpensively using a towed 30 channel land streamer and a rubberband accelerated weight drop seismic source data processed using the masw method imaged the subsurface to a depth of about 20 m and allowed detection of the overburden gross bedding features and fault zone the fault zone was characterized by a lower shear wave velocity vs than the competent bedrock consistent with a large scale fault secondary fractures and in situ weathering the masw 2d vs section was further interpreted to identify dipping beds consistent with local geologic mapping mapping of shallow fault zones and dipping sedimentary rock substantially extends the applications of the masw method

inversion tectonics and the evolution of the high atlas mountains morocco based on a geological geophysical transect an edited version of this paper was published by the american geophysical union agu copyright 1998 agu see also http www agu org pubs crossref 1999 1998tc900015 shtml http atlas geo cornell edu morocco publications beauchamp1999 htm

geophysical and geomorphological investigations of a quaternary karstic paleolake and its underground marine connection in cassis bestouan cassis se france an original karstic system in a coastal alluvial plain located in a carbonate environment cassis provence se france was studied using a multi method approach electrical resistivity tomography gravimetric passive seismic survey combined with geomorphologic methods surface observations and drilling limestone dissolution and or cavity collapse led to the development of a polje which was filled rapidly by erosion of aptian marls the combination of several dating and paleoenvironmental proxies indicates that the polje was filled during a glacial period mis 6 8 or 10 i e in the 130 360 ka age range this discovery has implications for the understanding of karst processes the connection between the polje and the three km long bestouan underwater karstic conduit with submarine outlet is strongly suggested by sedimentological studies and geophysical prospections

intra messinian gypsum palaeokarst in the northern apennines and its palaeogeographic implications a short intra messinian continental period has been recognised in some north italian gypsum areas mostly under the form of palaeokarst deposits this emersion appears to have occurred only locally and is explained as caused by the intra messinian tectonic phase and a major sea level lowering evidences of this palaeokarst are mostly small although at some places the palaeontological content of its fillings is of great importance the discovery near zola predosa bologna of a new intra messinian extensive karst system and of its infilling sheds new light on the importance of this karst episode

geometry and kinematics of the south atlas front algeria and tunisia abstract the south atlas front is the structural boundary between the sahara platform and the atlas mountains it is frequently indicated as a foreland dipping monocline known as the sahara flexure earlier work generally considered that such a cover structure resulted from direct inversion of basement faults this assumption is not applicable to the studied area which is situated close to the algeria tunisia border our study demonstrates a thin skinned style characterised by ramp related folds ten parallel balanced cross sections give an interpretation for the south atlas front from negrine to gafsa about 100 km along strike the geometry at depth of each cross section is defined by forward modelling of each individual anticline the depth to detachment is defined using the geometric characteristics of the fault propagation folds well exposed along the deformation front in all sections the modelling is consistent with basal decollements located within cretaceous stratigraphic levels lateral changes of the tectonic style accommodated by tear faults are observed they seem related to lateral variations in the efficiency of the based decollement faults inducing either a jump of the decollement to another level or the development of en echelon folds the modelling predicts small rotations of cover sheets separated by large scale tear faults

acoustic structure and recent sediment transport processes on the continental slope of yesilirmak river fan eastern black sea high resolution acoustic data indicate that sediment erosion is a significant process in the continental slope of yesilirmak river fan occurring both related to the submarine canyons and in the open continental slope the sediment processes observed along the slope consist of sliding and debris flows on the canyon walls together with the recent erosional surfaces at the canyon heads wherever the canyons exist and slides and related scarp features structurally controlled by rotational faults in the central part of the open continental slope formation of slides both on the open slope and in canyon walls is a multi phase sliding process in which successive sliding events occur at the same location producing a vertically stacked sliding resulting in several relict slide features deeper parts in the sediments we conclude that gravitational loading on the steep slope is the main driving force for most of the erosional features and in place to place overpressured pore fluids due to gas accumulation can contribute the instability tributary canyon systems are observed on the slope with slide scars in the proximal part according to their different erosional structure these canyons can be separated into two groups as northern and southern sector canyon systems where the sediment bypass and hence erosional processes are much more active on the canyon heads in the southern sector than those in the northern part terrigenous sediment load from yesilirmak river is transported along downslope by successive hyperpycnal fluxes and the activity of turbidity currents along the channel axis acoustic data indicate that the continental slope of yesilirmak river fan is a classical deep sea turbidite system where we observe slide scars in proximal part and channel levee systems with slide and debris flow deposits inside the channels in the distal part with some small sized gullies

multi scale factors controlling the pattern of floodplain width at a network scale the case of the rhone basin france abstract in this study the floodplain width fw was assessed for the entire rhone catchment river network 32 160 km long to highlight controlling factors the fw data which is measured every kilometre on a digital elevation model dtm is aggregated into spatial homogenous segments using a pettitt break detection test resulting in aggregated geographical objects ago based on these agos an analysis of the variability of the floodplain width was performed the general pattern for the rhone network shows a downstream increase in fw related to the concept of river continuum this general pattern explains ca 30 of the variation in fw deviations from this general trend are however large values for floodplain widths are normalized for catchment scale to study deviations that do not depend on scale effects based on a conceptual model the main environmental parameters influencing fw were identified these parameters include lithology and different parameters that influence the river profile such as base level changes and tectonics sediment load and discharge an analysis of catchment wide patterns shows that the main variations on the scaling effect are caused by lithology superposed on this general scaling pattern disturbed by lithological variations are the variations in floodplain width caused by disturbances in the geomorphic system which influence floodplain slope sediment and water discharge and which include inherited landscapes although large data sets become increasingly available and the applied methodology reduces data noise data availability and quality still hampers studies at a larger scale nevertheless such information sources are becoming crucial because they are more and more accessible and diverse and the analysis is now easier with the increasing capacities of gis technologies as a result they are becoming very complementary to field studies to understand geomorphic processes at wider spatial and longer temporal scales in a sense the tradition of geomorphology may evolve in the next years with image data providing additional evidence of earth evolution

neotectonic deformation in the transition zone between the dead sea transform and the east anatolian fault zone southern turkey a palaeomagnetic study of the karasu rift volcanism in southern turkey ongoing differential impingement of arabia into the weak anatolian collisional collage resulting from subduction of the neotethyan ocean has produced one of the most complex crustal interactions along the alpine himalayan orogen several major transforms with disputed motions including the northward extension of the dead sea fault zone dsfz meet in this region to evaluate neotectonic motion on the amanos and east hatay fault zones considered to be northward extensions of the dsfz the palaeomagnetism of volcanic fields in the karasu rift between these faults has been studied remanence carriers are low ti magnetites and all except 5 of 51 basalt lavas have normal polarity morphological polarity and k ar evidence show that rift formation occurred largely during the brunhes chron with volcanism concentrated at 0 66 0 35 ma and a subsidiary episode at 0 25 0 05 forty four units of normal polarity yield a mean of d i 8 8 54 7 with inclination identical to the present day field and declination rotated clockwise by 8 8 4 0 within the 15 km wide hassa sector of the karasu rift the volcanic activity is concentrated between the amanos and east hatay faults both with left lateral motions which have rotated blocks bounded by nw se cross faults in a clockwise sense as the arabian block has moved northwestwards an average lava age of 0 5 ma yields a minimum cumulative slip rate on the system bounding faults of 0 46 cm year according with the rate deduced from the africa arabia euler vector and reduced rates of slip on the southern extension of the dsfz during plio quaternary times estimates deduced from offsets of dated lavas flows and morphological features on the amanos fault zone tectonophysics 344 2002 207 are lower 0 09 0 18 cm year probably because they are limited to surface fault breaks and do not embrace the seismogenic crust results of this study suggest that most strike slip on the dsfz is taken up by the amanos east hatay afrin fault array in southern turkey comparable estimates of quaternary slip rate are identified on other faults meeting at an unstable fff junction dsfz east anatolian fault zone karatas fault zone a deceleration in slip rate across the dsfz and its northward continuation during plio quaternary times correlates with reorganization of the tectonic regime during the last 1 3 ma including tectonic escape within anatolia establishment of the north and east anatolian fault zones bounding the anatolian collage in mid late pliocene times a contemporaneous transition from transpression to transtension and concentration of all basaltic magmatism in this region within the last 1 ma

palaeo stresses inferred from macro and microfractures in the balazuc 1 borehole gpf programme contribution to the tectonic evolution of the cevennes border of the se basin of france abstract the scientific borehole balazuc 1 was drilled on the ardeche margin of the se basin of france for the purpose of studying fluid rock interactions in stratiform reservoirs in a tectonically controlled area a structural study was made of oriented cores from the drill hole between the depths of 1218 and 1729 5 m the various types of fracture that could have been used during fluid transfers have been described and analysed four major faults and 335 minor faults and tension gashes mineralized in carbonates anhydrite and sulphides were intersected at the bottom of the hole one of the major faults brings into contact rocks of triassic age and a formation attributed to the upper palaeozoic the other faults have caused thinning of certain units of the lower middle triassic micro structural study of the fault planes has enabled characterization of the tectonic episodes by which the triassic and lower liassic sedimentary rocks were affected these episodes discussed in the context of the ligurian tethys were 1 e w synsedimentary extension during the early middle triassic that caused tilting to the southeast of the upper palaeozoic and lower middle triassic successions this continued into the late triassic 2 an episode of n s extension during the early lias characterized by hydroplastic type faults probably the result of a local variation of the stress field in a trans tensional regime 3 the major period of activity on the uzer fault with downthrow of more than 1000 m that continued from the lotharingian late sinemurian to the early bathonian it was not possible to calculate the stress tensor for this period because no secondary fault system developed in the lower block traversed by the borehole brittle deformation at this time seems to have been concentrated on the major structures 4 approximately n s extension possibly end jurassic to earliest cretaceous during which the tension gashes mineralized in carbonates and pyrite were formed in the rhaetian and hettangian deposits 5 three compressive and or strike slip episodes attributed to the cenozoic pyrenean and alpine phases of deformation the oligocene extensional phase was not recognized in the borehole

present day strain distribution across a segment of the central bend of the north anatolian fault zone from a persistent scatterers insar analysis of the ers and envisat archives

imaging and monitoring of the shallow subsurface using spatially windowed surface wave analysis with a single permanent seismic source abstractdevelopment of shallow subsurface monitoring systems is important for monitoring the ground stability of shallow formation and also for conventional deep seismic monitoring because with cu

retrieval of local surface wave velocities from traffic noise an example from the la barge basin wyoming abstract in regions where active source seismic exploration is constrained by limitations of energy penetration and recovery cost and logistical concerns or regulatory restrictions analysis of natural source seismic data may provide an alternative in this study we investigate the feasibility of using locally generated seismic noise in the 2 6 hz band to obtain a subsurface model via interferometric analysis we apply this technique to three component data recorded during the la barge passive seismic experiment a local deployment in south western wyoming that recorded continuous seismic data between november 2008 and june 2009 we find traffic noise from a nearby state road to be the dominant source of surface waves recorded on the array and observe surface wave arrivals associated with this source up to distances of 5 kms the orientation of the road with respect to the deployment ensures a large number of stationary points leading to clear observations on both in line and cross line virtual source receiver pairs this results in a large number of usable interferograms which in turn enables the application of standard active source processing methods like signal processing common offset stacking and traveltime inversion we investigate the dependency of the interferograms on the amount of data on a range of processing parameters and on the choice of the interferometry algorithm the obtained interferograms exhibit a high signal to noise ratio on all three components rotation of the horizontal components to the radial transverse direction facilitates the separation of rayleigh and love waves though the narrow frequency spectrum of the surface waves prevents the inversion for depth dependent shear wave velocities we are able to map the arrival times of the surface waves to laterally varying group and phase velocities for both rayleigh and love waves our results correlate well with the known geological structure we outline a scheme for obtaining localized surface wave velocities from local noise sources and show how the processing of passive data benefits from a combination with well established exploration seismology methods we highlight the differences with interferometry applied to crustal scale data and conclude with recommendations for similar deployments

geochemistry and geochronology of meta igneous rocks from the tokat massif north central turkey implications for tethyan reconstructions located in the eastern pontides of the sakarya zone in north central turkey the tokat massif records the closure of both the paleo tethyan karakaya complex and neo tethyan ocean basins meta igneous samples collected from the region were studied to determine their sources and ages we find significant geochemical differences between metagabbros of the karakaya and neo tethyan units in terms of their trace elements neo tethyan rocks are consistent with generation in an island arc setting whereas karakaya assemblages were likely generated in an oceanic spreading center environment karakaya metagabbros also contain glaucophane consistent with subduction subsequent to formation small 2 50 m zircon and baddeleyite grains from four karakaya metagabbros were dated in thin section using an ion microprobe the results demonstrate the reliability of the method to directly constrain the tectonomagmatic history of these types of assemblages the rocks yield late permian early triassic 238u 206pb crystallization ages of 258 14 ma 1 zircon and 254 8 ma 1 baddeleyite and an early cretaceous minimum metamorphic age of 137 8 ma 1 zircon some zircon grains and baddeleyite grains with zircon overgrowths yield early to middle jurassic ages here we present a model in which metamorphism and deformation in this region occurred during northward subduction and closure of a paleo tethyan ocean basin and accretion of the karakaya units to the laurasian continental margin this was followed by the onset of closure of the neo tethys during the campanian paleocene and accretion of island arc units to the tokat region

the north anatolian fault zone distributed neogene deformation in its northward convex part abstract the north anatolian fault zone is composed of two almost rectilinear branches which join in a northward convex bend in this bent zone the pontide anatolide collisional system has been cut across by two transpressional belts of fold and thrust and wrench faults of lower neogene age these structures were reactived during the neotectonic period the time of deposition of the pontus group for both of these deformational events and up to the present the tectonic regime remained generally transpressional with a nw se direction of compression and a ne sw direction of extension it is only recently during the upper pleistocene that the dextral wrench faults became more localized and more straight than previously the complexity of the eastern part of the north anatolian fault zone is better understood if one takes into account the role of inherited miocene pliocene transpressional structures

surface sediment around the jabuka islet and the jabuka shoal evidence of miocene tectonics in the central adriatic sea abstract this paper is conceived as a contribution to understanding the tectonic setting in the jabuka region in the central adriatic sea one of the seismically active regions within the mediterranean this seismicity is the result of the compressional tectonics within the adria microplate accompanied by halokinetic activity the jabuka islet and the jabuka shoal appear to be triassic igneous bodies extruded by diapir tectonics sedimentological mineralogical and micropaleontological analyses of the surface sediments were done to provide insights into the depositional environment around these igneous outcrops coarse grained gravelly sands surrounding the jabuka islet and the jabuka shoal are composed predominantly of biogenous detritus containing small amounts of particles derived from igneous rocks this highly carbonate sediment cover has been formed in the low energy environment below wave base and without terrigenous supply from remote areas a peculiar finding of reworked lower miocene foraminiferal assemblage in the recent surface sediment accompanied with re interpreted seismic profile was used to propose a conceptual geodynamic model for the jabuka diapir protrusion it suggested miocene age for the earliest protrusion of the jabuka diapir followed by further plio quaternary growth and shaping together with mostly paleogene fossil calcareous nannoplankton fossil foraminifera were presumed to have been weathered from the pierced and extruded overburden rocks and admixed to recent slowly forming carbonate skeletal association typical for cool temperate depositional environments

evolution of an early eocene pull apart basin in the central pontides northern turkey new insights into the origin of the north anatolian shear zone although the north anatolian shear zone is one of the main lithospheric scale strike slip deformation zones in the world playing a prominent role in the complex geodynamic interaction between the eurasian anatolian and arabian plates the onset time of its activity remains highly controversial here we tackle this issue by utilizing nannofossil biostratigraphy on deposits from the tascilar basin a pull apart basin that we have identified inside the north anatolian shear zone overprinting the intra pontide suture zone the syn tectonic sedimentary succession of the tascilar basin developed completely during the early eocene ypresian cne4 cne5 zones the strike slip faulting related to the initial onset of the north anatolian shear zone can likely be constrained within the ypresian suggesting that the westward escape of the anatolian plate along the north anatolian shear zone started in the early eocene this article is protected by copyright all rights reserved

last glacial aeolian landforms and deposits in the rhone valley se france spatial distribution and grain size characterization abstract in the rhone valley a north south oriented cenozoic rift in southeast france thick pleistocene loess deposits have been recognized since the beginning of the last century these loess records which are disconnected from the north european loess belt nelb are of significant interest to document the evolution of perimediterranean landscapes and environments during the last glacial to overcome the poor precision of available aeolian distribution maps aeolian deposits were mapped using the topsoil textural database provided by the land use and cover area frame statistical survey project lucas the grain size distribution of aeolian sand and loess was first determined using 116 samples taken from surveyed outcrops then the areas showing a similar grain size composition were extracted from the lucas rasters the resulting map reproduces the conventional maps correctly but suggests a more significant extension of loess in better agreement with the known distribution of outcrops the map shows that the distinctive morphology of the valley dominantly controls the distribution of aeolian deposits the deflation related landforms i e yardangs closed depressions pans and desert pavements are widespread south of narrowings of the rhone valley between latitudes 44 n and 45 n they indicate palaeowinds blowing from the north northwest aeolian sand loessic sand sandy loess and loess deposits successively spread on both sides of the rhone river the loess is characterized by a coarse texture main mode around 60 m strong local thickness 5 m limited extension and abundant bioturbation this preservation results from the persistence of a shrub vegetal cover during the coldest and driest phases of the last glacial that allowed for trapping the saltating and suspended particles close to the alluvial sources

tectonic evolution of the niksar and tasova erbaa pull apart basins north anatolian fault zone their significance for the motion of the anatolian block abstract the tasova erbaa and niksar basins are two adjacent pull apart basins along the north anatolian fault zone nafz within the tasova erbaa basin sedimentary lithofacies of the upper pontus formation plio pleistocene are asymmetrically distributed with laterally derived alluvial fans coarse braid plain deposits and axial braided stream deposits dominating the northern and western parts of the basin the basin has gently dipping sediments locally affected by pervasive extensional t faulting isolated compressional structures are associated with master faults deformation zone width 500 m pervasive extensional faults t and r and late stage pdz parallel compressional faults are also present an additional set of extensional faults trends perpendicular to the pdz accommodating secondary pull apart stretching within the basin the distribution of sedimentary facies and structural styles is consistent with that predicted by models for pull apart basins the adjacent niksar basin is an active pull apart basin possibly as young as 0 5 1 ma its modern drainage and sedimentary facies are symmetrically arranged adding the lengths of the tasova erbaa and niksar basin suggests 80 km total displacement along the north anatolian fault which is consistent with seymen itu ph d thesis 1975 sengor j geol soc 136 1979 269 282 and armijo et al tectonophysics 243 1999 135 154 who observed about 85 5 km total displacement along the north anatolian fault the change in course of the north anatolian fault marked by the formation of the niksar ezinepazari segment and this new geometry suggest that the anatolian block is rotating anticlockwise by having two separate poles one located near damascus and the other occurring north of the sinai peninsula this change may also mark the transfer of the anatolian triple junction from erzincan to karliova about 1 ma ago furthermore it appears that while the fault shortcuts the older basin a new generation of pull apart basins is formed due to changes of boundary conditions along the fault zone

are u th dates correlated with historical records of earthquakes constraints from coseismic carbonate veins within the north anatolian fault zone u th dating of carbonate veins in connection with active tectonics has recently been used as an attractive tool for constraining the absolute timing of late quaternary crustal deformations in this study for the first time we correlate u th ages of travertine deposits in coseismic fissures along the north anatolian fault zone with records of paleoseismological studies supported by historical earthquake catalogued data u th ages are assessed in relation to the recurrence interval and the size and epicenter distance of major holocene earthquakes our statistical evaluations on age correlations indicate that the carbonate vein precipitation is concentrated in eight different periods along the north anatolian fault zone the periods are well correlated with historical earthquake records and with previous dating results of the nearby trench studies at least six of the periods correspond to the earthquakes reported in the historical catalogues the age correlations of carbonate precipitation intervals for the last millennium show a recurrence along the eastern north anatolian fault zone with a mode at 130 330 years that is consistent with a previously proposed paleoseismic recurrence interval of the fault recorded events in carbonate veins indicate a close epicenter d vi paleoearthquakes our results suggest that coseismic carbonate veins could be used to determine paleoseismic records as a supplementary tool to augment paleoseismological techniques this tool has advantages over traditional paleoseismological methods for the understanding of long term earthquake behavior particularly for prehistoric late pleistocene events which cannot be dated easily by traditional paleoseismological methods

deep confined karst detection analysis and paleo hydrology reconstruction at a basin wide scale using new geophysical interpretation of borehole logs summary deep karst voids can be identified by a new method of geophysical interpretation of commonly used borehole logs in deeply confined carbonate aquifers we show that deep buried karst voids can be characterized by combining this geophysical interpretation together with geological and hydrological data and with known speleological constraints we demonstrate how this characterization can reveal past hydrological regimes and allow mapping of karst distribution on a basin wide scale a combined analysis of geophysical geological hydrological and speleological data in the confined yarkon taninim aquifer israel led us to reconstruct past groundwater levels at different relief and sea levels with the karst voids as a marker for long term flow close to the water table paleo canyons along the mediterranean sea shoreline strongly affected the region s paleo hydrology by serving as major outlets of the aquifer during most of the cenozoic we conclude that intensive karstification was promoted by flow periods of longer duration and or higher flux and flow velocities close to the aquifer s past and present outlets in addition we suggest that karst voids found under shallow confinement were developed by renewed aggressivity due to hypogene water rising in cross formational flow becoming mixed with fresh lateral water flow from the east

the effect of river dynamics induced by the messinian salinity crisis on karst landscape and caves example of the lower ardeche river mid rhone valley abstract the karstic canyon of lower ardeche is located in the middle rhone valley which is directly tributary to the mediterranean sea the rhone river is emblematic of the messinian salinity crisis msc impact on landscape morphology along the edge of the saint remeze plateau the rhone valley displays four benchmark levels generated by the msc the pre evaporitic abandonment surface 1 the messinian erosional surface 2 the marine non marine surface of the pliocene ria 3 and the pliocene abandonment surface 4 the study of these benchmark levels allows us to reconstruct the evolution of the regional base level over the last 6 ma we obtain a curve for base level evolution that provides a geodynamic reference which is used to investigate the morphogenesis of the saint remeze karstic plateau the ardeche river downcuts the saint remeze plateau in a deep canyon from vallon pont d arc to the west to its confluence with the rhone to the east several abandoned valleys are present along the western edge of the saint remeze plateau at the inlet of the ardeche canyon in these abandoned valleys the fluvial deposits are related to several periods from the pliocene onwards they provide important insights into the fluvial dynamics a 160 m thick aggradation sequence infilled the ardeche canyon during the pliocene this aggrading river caused the first lateral shifting as an aggradation epigenesis this first infilling shows that the ardeche canyon already existed before the pliocene secondly it has been demonstrated that the ardeche canyon is downcut into the pre evaporitic surface of the saint remeze plateau dated to 5 45 ma martini j 2005 etude des paleokarsts des environs de saint remeze ardeche france mise en evidence d une riviere souterraine fossilisee durant la crise de salinite messinienne karstologia 45 46 1 18 consequently the canyon downcutting is entirely due to the msc and occurred during a time span of only 100 000 years based on these observations it is possible to elucidate the curve of the regional base level evolution hence we are able to propose a new interpretation of the geomorphological evolution of the saint remeze karstic plateau and its cave levels for the last 6 ma the cave levels consist in underground short cuts of the surface meanders they mainly developed during the pliocene aggradation cycle the chauvet cave famous for its palaeolithic paintings corresponds to one of these underground short cuts the aggradation period ends at the end of the pliocene with long high level riverbed stability it favours the development of large low gradient surfaces as pediments the complete messinian pliocene eustatic cycle is responsible for the downcutting of the ardeche canyon and its infilling during the pliocene consequently karst developed according to the base level oscillations as low gradient surfaces and as cave levels for the study of the peri mediterranean caves and karst areas we propose to apply the lower ardeche valley evolution model based on the base level oscillations during and after the msc

the generating mechanisms of the august 17 1999 izmit bay turkey tsunami regional tectonic and local mass instabilities causes abstract the m w 7 4 earthquake that affected the northwestern part of turkey on august 17 1999 and in particular the gulf of izmit had dramatic consequences also as regards tsunami generation the main cause of the earthquake was a dextral strike slip rupture that took place along different segments of the western part of the north anatolian fault wnaf the rupture process involved not only a number of distinct strike slip fault segments but also dip slip ancillary faults connecting the main transcurrent segments the general picture was further complicated by the occurrence of subsidence and liquefaction phenomena especially along the coasts of the izmit bay and in the sapanca lake tsunami effects were observed and measured during post event surveys in several places along both the northern and the southern coasts of the bay the run up heights in most places were reported to lie in the interval 1 3 m but in the small town of degirmendere where a local slump occurred carrying underwater buildings and gardens of the waterfront sector eyewitnesses reported water waves higher than 15 m the purpose of this work is to investigate on the causes of the tsunami by means of numerical simulations of the water waves we show that the tsunami was a complex event consisting at least of the combination of a regional event due to tectonic causes and of a local event associated with the mass failure as to the first we are able to demonstrate that the observed tsunami cannot be explained only in terms of the sea bottom dislocation produced by the main right lateral dislocation but that the prominent contribution comes from the displacement associated with the secondary shallow normal faults furthermore the large waves and effects seen in degirmendere can be explained as the consequence of the slump by means of a stability analysis based on an original method making use of the limit equilibrium concept we show that the slump was highly stable before the earthquake and that it was triggered by seismic waves simulation of the tsunami induced by the slump was carried out by a two step numerical code that computes the landslide motion first and then the generated water wave propagation it is shown that the computed local tsunami matches the experimental data

recent temporal change in the stress state and modern stress field along the north anatolian fault zone turkey summary the north anatolian fault naf is a dextral strike slip fault which runs about 1400 km from east to west from the karliova triple junction to the aegean domain it was active during the plio quaternary as a consequence of the collision between the eurasian and arabian plates the naf intracontinental deformation zone contributes with the sinistral east anatolian fault to the westward extrusion of anatolia as a consequence of the northward drift of arabia the central naf zone forms a northward convex bend where the eastern naf n110 e trending segment extending from karliova is connected to the western naf n75 e trending segment running to aegea analysing the slip occurring in major earthquakes around the naf we show that the present day stress pattern along the naf agrees with stress magnitude and strike variations from east to west the stress regime along the naf is nnw trending hmax 1 transpression in eastern naf this progressively changes westwards to nw trending 1 transtension in central anatolia this lateral variation means a relative decrease of the hmax magnitude which evolves progressively to an extensional regime 1 vertical around the westernmost naf characterized by a nne trending hmin 3 the drastic change in the tendency of the regional stress state in the north anatolian block from compressional to extensional is effective within the central naf bend the stress regime determined by inversion of slip vectors measured on fault planes of various scales confirms the present day transtensional regime in the central part of the naf bend however the fault kinematic analysis of quaternary stress states within the central naf indicates that this stress state was not continuous throughout the quaternary indeed chronologies of fault slip vectors provide evidence for two distinct quaternary regional strike slip stress states within this zone both states have consistent ne and nw trending 3 and 1 axes respectively but have significantly different r values the change in the strike slip stress regime probably occurred in the middle pleistocene the older mean stress state is characterized by a n142 8 e trending 1 a n52 13 e trending 3 and a mean arithmetic rm value of 0 75 which indicates that the regional stress regime is transpressional the younger strike slip regime is characterized by a n142 14 e 1 axis a n52 10 e 3 axis and a mean rm of 0 24 which indicates the transtensional character for this regime the low r values of the stress deviators related to the recent stress state reflect normal component slips these temporal and spatial stress changes along the naf result from the coeval influence of forces due to the aegean subduction in the west and to the northward drift of arabia in the east over these boundary forces shear is superimposed along the naf which accommodates the anatolia extrusion however the timing of the temporal stress change permits the suggestion that the quaternary stress regime variation in north anatolia is mainly due to the influence of the aegean domain

on the use of the norwegian geotechnical institute s prototype seabed coupled shear wave vibrator for shallow soil characterization ii joint inversion of multimodal love and scholte surface waves summary seismic data generated by a novel seabed coupled shear wave vibrator prototype and recorded by a densely populated multicomponent ocean bottom cable allowed several modes of propagation of love and scholte waves to be retrieved in a relatively wide frequency band both global dispersion curves and local dispersion curves are extracted in the frequency wavenumber f k domain and inverted with a multimodal joint scholte and love wave inversion algorithm monte carlo inversion is used for a estimating the global s wave velocity profile of the seabed sediments whereas laterally constrained inversion is used to detect lateral variations of the layer interface depths the results are in agreement and allowed consistent full waveform simulation to be performed the investigation depth is limited to around 40 m due to the low shear wave velocities within the shallow clay layer

discussion on the article coastal and inland karst morphologies driven by sea level stands a gis based method for their evaluation by canora f fidelibus d and spilotro g comments are presented on the article by canora et al 2012 dealing with karst morphologies driven by sea level stands in the murge plateau of apulia southern italy our comments start from cave levels that are considered in the cited article as a proof of sea level stands we argue that the presence of sub horizontal passages in cave systems is not a sufficient condition for correlating them with hypothetical past sea level stands such a correlation must be based upon identification of speleogenetic features within the karst systems and or geological field data the problems encountered when using cave surveys for scientific research and their low reliability especially in the case of old surveys are then treated since they represent a crucial point in the paper object of this discussion eventually we present some final consideration on cave levels and terraces and on the specific case study pointing out once again to the need in including geological field data to correctly find a correspondance between flat landforms and sea level fluctuations our main conclusion is that field data and information on speleogenesis of the underground karst landforms cannot be disregarded in a study that claims to deal with the influence of sea level changes on caves copyright 2013 john wiley sons ltd

fragmentation of the adriatic promontory new chronological constraints from neogene shortening rates across the southern alps ne italy key points folded alluvial surfaces and balanced cross section constrain post lgm and neogene shortening rates decrease in shortening rate and change in compression direction are inferred at 1 2 ma kinematic reorganization is best explained by a shift from nubia driven to adria driven convergence abstract the eastern southern alps are located at the northern tip of the adria microplate which imposes 2 0 2 5 mm yr of n s convergence relative to stable eurasia we map surface evidence of recent folding faulting in this area from a 5 m dem in the eastern part of the belt observations reveal a 30 km wide zone of active folding composed of at least five growing anticlines the most recent ones warped the post glacial alluvial surface by 10m combining these findings with published geological and geophysical data allows us to infer that active thrusting occurs along a single deeply rooted thrust which accommodates the indentation of the adriatic crust resolving the observed pattern of uplift on the inferred fault geometry indicates that nne ssw shortening across the eastern southern alps has occurred at a rate of about 1 5 mm yr over the post glacial period on the other hand a balanced cross section for the eastern southern alps at the scale of the upper crust constrains a minimum of 43 km of finite shortening over the last 14ma yielding a shortening rate of about 3 mm yr which is two times higher than the post glacial shortening rate this decrease in the shortening rate is associated to the pleistocene activation of new thrusts that is compatible with a change in the direction of compression the inferred local change in the kinematics of thrusting during the pleistocene is consistent with a change from nubia imposed to adria imposed convergence indicating that the fragmentation of the adriatic promontory could have occurred 1 2 ma ago

active tectonics of the aegean region the aegean sea and its surrounding regions comprise one of the most rapidly deforming parts of the alpine himalayan mountain belt though the deformation of the belt as a whole is related to thc northward move ment of africa arabia and india relative to eurasia the tectonics of the aegean region itself is dominated by strike slip and extensional motions the actively deforming part of the aegean region is not large about 700 x 700 km2 compared with that in asia yet it has had an influence on our views of continental tectonics disproportionate to its size and comparable perhaps only to tibet fundamental contributions from the aegean have been made to many topics including