contribution to the seismotectonics of eastern turkey from moderate and small size events an edited version of this paper was published by the american geophysical union agu copyright 2003 agu see also http www agu org pubs crossref 2003 2003gl018258 shtml http atlas geo cornell edu turkey publications orgulu et al 2003 htm

sedimentation in pull apart basins active examples in eastern turkey the erzincan susehri niksar and lake hazar basins are actively evolving pull apart basins in eastern turkey their structural drainage and depositional systems generally support a pull apart basin sedimentation model based on ancient pull apart basin deposits this model involves marginal coarse grained sedimentation adjacent to master faults axial fine grained sedimentation away from master faults and high sedimentation rates however studies of the turkish pull apart basins suggest the following refinements in the model 1 detailed sedimentary facies patterns and the dominant facies of a pull apart basin vary according to basin shape climate drainage character and volcanic activity depositional environments near fault bounded margins include alluvial fan fan delta and alluvial apron depositional environments in central areas away from fault bounded margins include active braid plain inactive braid plain meander plain salt playa marsh lacustrine mouth bar delta and volcanic 2 i

elastic and inelastic triggering of earthquakes in the north anatolian fault zone abstract deformation models used to explain the triggering mechanism often assume pure elastic behaviour for the crust and upper mantle in reality however the mantle and possibly the lower crust behave viscoelastically particularly over longer time scales consequently the stress field of an earthquake is in general time dependent in addition if the elastic stress increase were enough to trigger a later earthquake this triggered event should occur instantaneously and not many years after the triggering event hence it is appropriate to include inelastic behaviour when analysing stress transfer and earthquake interaction in this work we analyse a sequence of 10 magnitude m s 6 5 events along the north anatolian fault between 1939 and 1999 to study the evolution of the regional coulomb stress field we investigate the triggering of these events by stress transfer taking viscoelastic relaxation into account we evaluate the contribution of elastic stress changes of post seismic viscoelastic relaxation in the lower crust and mantle and of steady tectonic loading to the total coulomb stress field we analyse the evolution of stress in the region under study as well as on the rupture surfaces of the considered events and their epicentres we study the state of the coulomb stress field before the 1999 izmit and duzce earthquakes as well as in the marmara sea region in general the coulomb stress failure criterion offers a plausible explanation for the location of these events however we show that using a purely elastic model disregards an important part of the actual stress increase decrease in several cases post seismic relaxation effects are important and greater in magnitude than the stress changes due to steady tectonic loading consequently viscoelastic relaxation should be considered in any study dealing with coulomb stress changes according to our study and assuming that an important part of the rupture surface must be stressed for an earthquake to occur the most likely value for the viscosity of the lower crust or mantle in this region is 5 10 17 10 18 pa s our results cannot rule out the possibility of other time dependent processes involved in the triggering of the 1999 duzce event however the stress increase due to viscoelastic relaxation brought 22 of the 1999 duzce rupture area over the threshold value of c 0 01 mpa 0 1 bar and took the whole surface closer to failure by an average of 0 2 mpa finally we argue that the marmara sea region is currently being loaded with positive coulomb stresses at a much faster rate than would arise exclusively from steady tectonic loading on the north anatolian fault

wood recruitment and retention the fate of eroded trees on a braided river explored using a combination of field and remotely sensed data sources abstract this paper investigates wood recruitment and deposition dynamics in a large gravel bed braided river tagliamento river italy we used a combination of field measurements automatically repeated ground images and remotely sensed surveys to quantify wood input through bank erosion and associated downstream deposition two sites were investigated where floods caused the erosion of vegetated island edges a lidar survey preceding the erosion events provided data on the morphology and vegetation structure of the eroded areas allowing estimation of the number of trees that were uprooted sequences of ground based images acquired automatically and supported by field measurements showed the time number and location of deposited trees results show that the complex morphology of braided rivers induces specific deposition patterns we observed wide dispersal of wood on gravel bars with jams characterised by a small number of logs on average 2 3 and in many cases only a single log a large proportion of the eroded trees up to 40 were deposited on the nearest downstream bar this illustrates significant wood retention close to the recruitment site with the remaining wood dispersed widely downstream differences in the observed level of local wood retention were associated with the proximity of the erosion site to the main channel and differences were also observed in retention between the peak and the falling limb of flood events confirming that water depth and probably flow velocity are the crucial parameters controlling wood deposition

mechanism of the 1992 erzincan earthquake and its aftershocks tectonics of the erzincan basin and decoupling on the north anatolian fault summary the 1992 march 13 erzincan earthquake ms 6 8 affected the erzincan basin on the eastern part of the north anatolian fault naf this event occurred on the eastern tip of a westward propagating series of major north anatolian earthquakes between 1939 and 1967 ambraseys 1970 it is located within a key region of eastern anatolia which displays both expulsion of the anatolian block towards the west and regional n s convergence due to the arabian eurasian collision philip et al 1989 a reinterpretation of the tectonics of the erzincan basin is made from field information and the analysis of satellite images a model explaining the development of the basin is proposed it combines a pull apart on the naf with the effect of two compressional wedges one is formed by the northeast anatolian fault neaf and the naf the other around pulumur is limited by the ovacik fault of and the naf both e w extension and n s compression occur according to this model normal faulting on the southwestern border and extension related quaternary rhyolitic volcanic domes along the northeastern boundary of the basin support the proposed e w extension the block limiting the southern side of the basin is uplifted and displaced left laterally along the of suggesting southward growth of the basin a kinematic model of the 1992 erzincan earthquake combines aftershock field information neotectonic observations satellite image interpretation and bodywaveform inversion the complex earthquake rupture starts on the naf and propagates bilaterally westward rupture propagation progresses along the northern border of the basin eastward propagation is shifted on a segment of the naf south of the euphrates and ends within the pulumur wedge both branches are connected by a system of normal faults the main focal mechanism is strike slip with a slight normal component o 122 63 164 the strongest aftershock mechanism is compatible with n s compression within the pulumur wedge aftershock mechanisms and stress tensor analyses give detailed insight into the earthquake sequence the 1992 erzincan earthquake is located between two segments of the naf that suffered large destructive earthquakes in the past the 1939 earthquake ms 8 2 ruptured 370 km west of erzincan the last major earthquake east of the erzincan basin occurred in 1784 rupturing a segment of at least 75 km length this area has displayed a seismic gap since then the mechanism of the main shock and the absence of aftershock activity east of tanyeri indicate decoupling between the 1992 event and the 1784 gap aftershocks within the pulumur wedge suggest that the probability of the occurrence of a future earthquake is higher on the of than in the 1784 earthquake gap

saturn s cloud structure and temporal evolution from ten years of hubble space telescope images 1994 2003 abstract we present a study of the vertical structure of clouds and hazes in the upper atmosphere of saturn s southern hemisphere during 1994 2003 about one third of a saturn year based on hubble space telescope images the photometrically calibrated wfpc2 images cover the spectral region between the near uv 218 255 nm and the near ir 953 1042 nm including the 890 nm methane band using a radiative transfer code we have reproduced the observed center to limb variations in absolute reflectivity at selected latitudes which allowed us to characterize the vertical structure of the entire hemisphere during this period a model atmosphere with two haze layers has been used to study the variation of hazes with latitude and to characterize their temporal changes both hazes are located above a thick cloud putatively composed of ammonia ice an upper thin haze in the stratosphere between 1 and 10 mbar is found to be persistent and formed by small particles radii 0 2 m the lower thicker haze close to the tropopause level shows a strong latitudinal dependence in its optical thickness typically 20 40 at the equator but 5 at the pole at 814 nm this tropospheric haze is blue absorbent and extends from 50 to 100 mbar to about 400 mbar both hazes show temporal variability but at different time scales first there is a tendency for the optical thickness of the stratospheric haze to increase at all latitudes as insolation increases second the tropospheric haze shows mid term changes over time scales from months to 1 2 years in its optical thickness typically by a factor of 2 such changes always occur within a rather narrow latitude band width 5 10 affecting almost all latitudes but at different times third we detected a long term 10 year decrease in the blue single scattering albedo of the tropospheric haze particles most intense in the equatorial and polar areas long term changes follow seasonal insolation variations smoothly without any apparent delay suggesting photochemical processes that affect the particles optical properties as well as their size in contrast mid term changes are sudden and show various time scales pointing to a dynamical origin

planetary scale waves and the cyclic nature of cloud top dynamics on venus abstract pioneer venus ocpp ultraviolet images spanning eight years have been analyzed objectively to derive quantitative information on the properties of planetary scale wave modes at the venus cloud tops we infer propagation characteristics for longitudinal wavenumber 1 by fourier analyzing time series of longitudinal mean normalized image brightness the dominant equatorial mode during 1979 80 was the 4 day periodicity associated with zonal motion of the y feature the difference between this and the 4 7 day equatorial rotation period derived from the tracking of small cloud features implies that the y is a propagating wave with a prograde phase speed of about 15 ms 1 relative to the wind simultaneous time series of cloud tracked wind fluctuations also exhibit a 4 day periodicity lending support to the wave interpretation the prograde propagation and equatorial confinement of the wave and the absence of analogous meridional wind fluctuations identify it as a kelvin wave zonal winds peak near the

the role of vegetation in the formation of anabranching channels in an ephemeral river northern plains arid central australia as the distribution and abundance of vegetation in drylands is often controlled by the greater availability of water along river channels riparian vegetation has the potential to influence significantly dryland river form process and behaviour this paper demonstrates how a small indigenous shrub the inland teatree melaleuca glomerata influences the formation and maintenance of anabranching channels in a reach of the ephemeral marshall river northern plains arid central australia here the marshall is characterized by ridge form anabranching where water and sediment are routed through subparallel multiple channels of variable size which occur within a typically straight channel train channels are separated by channel train ridges narrow flow aligned vegetated features or by wider islands by providing a substantial element of boundary roughness dense stands of teatrees growing on channel beds or atop the ridges and islands influence flow velocities flow depths and sediment transport resulting in flow diversion bank and floodplain erosion and especially sediment deposition ridges and islands represent a continuum of forms and their formation and development can be divided into a three stage sequence involving teatree growth and alluvial sedimentation 1 teatrees colonize a flat sandy channel bed initiating the formation of ridges by lee side accretion individual ridges grow laterally vertically and longitudinally and maintain a geometrically similar streamlined lemniscate form that presents minimum drag 2 individual ridges grow in size and interact with neighbouring ridges causing the lemniscate forms to become distorted ridges in the lee of other ridges tend to be protected from the erosive effects of floods and survive whereas individual teatrees or small ridges exposed to flow concentrated between larger ridges tend to be removed 3 ridges lengthen and coalesce with downstream ridges eventually subdividing the channel train into well defined anabranches this sequence turns a channel initially obstructed with dense and chaotic stands of teatrees into a well organized system of ridge form anabranches in the moderate to low gradient marshall river which is colonized by an abundance of within channel vegetation and subject to declining downstream discharges this helps to minimize flow resistance thereby maintaining an efficient water and sediment flux copyright 2000 john wiley sons ltd

cassini iss observation of saturn s north polar vortex and comparison to the south polar vortex we present analyses of saturn s north pole using high resolution images captured in late 2012 by the cassini spacecraft s imaging science subsystem iss camera the images reveal the presence of an intense cyclonic vortex centered at the north pole in the red and green visible continuum wavelengths the north polar region exhibits a cyclonically spiraling cloud morphology extending from the pole to 85 n planetocentric latitude with a 4700 km radius images captured in the methane bands which sense upper tropospheric haze show an approximately circular hole in the haze extending up to 1 5 latitude away from the pole the spiraling morphology and the eye like hole at the center are reminiscent of a terrestrial tropical cyclone in the system iii reference frame rotation period of 10h39m22 4s seidelmann et al 2007 archinal et al 2011 the eastward wind speed increases to about 140 m s 1 at 89 n planetocentric latitude the vorticity is 6 5 1 5 10 4 s 1 at the pole and decreases to 1 3 1 2 10 4 s 1 at 89 n in addition we present an analysis of saturn s south polar vortex using images captured in january 2007 to compare its cloud morphology to the north pole the set of images captured in 2007 includes filters that have not been analyzed before images captured in the violet filter 400 nm also reveal a bright polar cloud the south polar morphology in 2007 was more smooth and lacked the small clouds apparent around the north pole in 2012 saturn underwent equinox in august 2009 the 2007 observation captured the pre equinox south pole and the 2012 observation captured the post equinox north pole thus the observed differences between the poles are likely due to seasonal effects if these differences indeed are caused by seasonal effects continuing observations of the summer north pole by the cassini mission should show a formation of a polar cloud that appears bright in short wavelength filters

fault location and rupture kinematics of the magnitude 6 8 1992 erzincan earthquake turkey from strong ground motion and regional records abstract the hypocenter location of the 13 march 1992 m 6 9 erzincan earthquake turkey and its rupture kinematics have been studied using local and regional seismic records to understand its relationship with the tectonic activity of the erzincan basin and of the north anatolian fault naf regional records of the mainshock and the largest aftershocks were used to locate the respective epicenters the mainshock s p travel time delay and the p wave polarization of the near source accelerogram record in erzincan erz calibrated by the aftershock records constrain the mainshock hypocenter to be located about 10 km to the east southeast of erzincan 39 42 3 n 39 35 2 e and at a best fit depth of about 9 km the activated fault is a major branch of the naf along the eastern edge of the basin hypocentral depths greater than about 16 km are not supported by the data the ground velocity record at erz has been synthesized for constraining the northwestward rupture assuming a kinematic model with constant slip and rupture velocity and a strike 125 for a large number of models the latter were constructed by varying the rupture parameters in a discrete domain the best fit fault models are located within 1 km of the epicenter above and have all their northwestern end within 5 km of erz the up dip limit of the rupture in the vicinity of erz ranges from 5 to 2 km in depth in agreement with the absence of surface breakage the estimated rupture velocity is 3 km sec the rise time is 0 35 sec and the mean slip of about 1 m is poorly resolved with a standard uncertainty of 0 5 m being strongly sensitive to the rupture velocity and to the fault location combining these results with the seismic moment and the source duration provided by other studies leads to a total rupture length ranging between 20 and 35 km the rupture thus propagated bilaterally on the naf and was confined within the limits of the basin stopping to the southeast near the intersection of the naf with the ovacik fault

an objective classification of saturn cloud features from cassini iss images abstract a k means clustering algorithm is applied to cassini imaging science subsystem continuum and methane band images of saturn s northern hemisphere to objectively classify regional albedo features and aid in their dynamical interpretation the procedure is based on a technique applied previously to visible infrared images of earth it provides a new perspective on giant planet cloud morphology and its relationship to the dynamics and a meteorological context for the analysis of other types of simultaneous saturn observations the method identifies 6 clusters that exhibit distinct morphology vertical structure and preferred latitudes of occurrence these correspond to areas dominated by deep convective cells low contrast areas some including thinner and thicker clouds possibly associated with baroclinic instability regions with possible isolated thin cirrus clouds darker areas due to thinner low level clouds or clearer skies due to downwelling or due to absorbing particles and fields of relatively shallow cumulus clouds the spatial associations among these cloud types suggest that dynamically there are three distinct types of latitude bands on saturn deep convectively disturbed latitudes in cyclonic shear regions poleward of the eastward jets convectively suppressed regions near and surrounding the westward jets and baroclinically unstable latitudes near eastward jet cores and in the anti cyclonic regions equatorward of them these are roughly analogous to some of the features of earth s tropics subtropics and midlatitudes respectively this classification may be more useful for dynamics purposes than the traditional belt zone partitioning temporal variations of feature contrast and cluster occurrence suggest that the upper tropospheric haze in the northern hemisphere may have thickened by 2014 the results suggest that routine use of clustering may be a worthwhile complement to many different types of planetary atmospheric data analysis

cloud features and zonal wind measurements of saturn s atmosphere as observed by cassini vims 1 we present an analysis of data about saturn s atmosphere from cassini s visual and infrared mapping spectrometer vims focusing on the meteorology of the features seen in the 5 m spectral window we present vims mosaics and discuss the morphology and general characteristics of the features backlit by saturn s thermal emission we have also constructed a zonal wind profile from vims feature tracking observation sequences using an automated cloud feature tracker comparison with previously constructed profiles from voyager and cassini imaging data reveals broad similarities suggesting minimal vertical shear of the zonal wind however areas of apparent wind shear are present in the vims zonal wind profile at jet stream cores in particular our analysis shows that the equatorial jet reaches speeds exceeding 450 m s 1 similar to speeds obtained during the voyager era this suggests that recent inferences of relatively slower jet speeds of 275 375 m s 1 are confined to the upper troposphere and that the deep 1 bar jet has not experienced a significant slowdown our measurements of the numerous dark spotted features seen in the vims mosaics reveals that most of these features have diameters less than 1000 km and reside in confined zonal bands between jet stream cores we propose that these spot features are vortices and that vims and imaging science subsystem are sensing the same vortices at two different pressure levels the local structure at the zonal jet streams remains complex as vims may be sensing cloud features that are deeper than the nh3 cloud deck

woody vegetation and channel morphogenesis in low gradient gravel bed streams in the ozark plateaus missouri and arkansas woody vegetation affects channel morphogenesis in ozark streams of missouri and arkansas by increasing local roughness increasing bank strength providing sedimentation sites and creating obstructions to flow variations in physiographic controls on channel morphology result in systematic changes in vegetation patterns and geomorphic functions with increasing drainage basin area in upstream reaches streams have abundant bedrock control and bank heights that typically are less than or equal to the rooting depth of trees in downstream reaches where valleys are wider and alluvial banks are higher vegetation has different geomorphic functions at drainage areas of greater than 100 200 km2 ozarks streams are characterized by longitudinally juxtaposed reaches of high and low lateral channel migration rates referred to as disturbance reaches and stable reaches respectively whereas stable reaches can develop stable forested floodplains if they are not farmed disturbance reaches are characterized by dynamic vegetation communities that interact with erosion and deposition processes disturbance reaches can be subdivided into low gradient and high gradient longitudinal zones low energy zones are characterized by incremental unidirectional lateral channel migration and deposition of gravel and sand bars the bars are characterized by prominent bands of woody vegetation and ridge and swale topography channel monitoring data indicate that densely vegetated bands of woody vegetation formed depositional sites during bedload transporting events the same floods caused up to 20 m of erosion of adjacent cutbanks scoured non vegetated areas between vegetation bands and increased thalweg depth and definition in high energy or riffle zones channel movement is dominantly by avulsion in these zones vegetation creates areas of erosional resistance that become temporary islands as the channel avulses around or through them woody vegetation on islands creates steep root defended banks that contribute to narrow channels with high velocities calculation of hydraulic roughness from density and average diameter of woody vegetation groups of different ages indicates that flow resistance provided by vegetation decreases systematically with group age mainly through decreasing stem density if all other factors remain constant the stabilizing effect of a group of woody vegetation on a gravel bar decreases with vegetation age

the saturnian ribbon feature a baroclinically unstable model images of saturn from the two voyager spacecraft showed few discrete atmospheric features in the low contrast latitudinal banding over the planet one unusual feature however was a narrow dark oscillatory structure encircling the planet in the light zone at 45 to 50 north this paper presents a description of this dark structure which we call the ribbon feature a wavelength of 5710 260 km is obtained from moderate resolution images which were used to produce a 360 image of the feature higher resolution image pairs were used to examine the local circulation which shows counterclockwise rotation north of the ribbon and clockwise rotation south of it the zonal circulation measurements show that it is located in a 120 m sec 1 westerly jet but with a small 5 m sec 1 meridional velocity the infrared spectrometer results from voyager showed the greatest thermal wind sheer in this latitude region the regions adjacent to the ribbon are of similar brightness except for the uv 3400 a filter images where the northern part of this zone is lighter than the southern section from this observation we have estimated that the disturbance associated with the ribbon feature extends to at least the 200 mbar level a study of a 120 section of the ribbon feature and the associated latitudinal thermal gradient by l a sromovsky h e revercomb r j krauss and v e suomi 1983 j geophys res 88 8650 8666 led them to suggest that it was produced by some form of baroclinic instability this proposal is considered here with other alternative types of instability we conclude that the ribbon feature could arise from a baroclinic instability we then develop a numerical model of such an instability that is consistent with the observed wavelength the vertical extent of the ribbon and the local latitudinal thermal profile

imaging the crustal structure throughout the east anatolian fault zone turkey by local earthquake tomography this paper presents new models of the seismic velocity structure of eastern anatolia turkey we applied a local earthquake tomography method to arrival time data produced by local and regional events in eastern anatolia to understand the three dimensional seismic velocity and vp vs models and their correlation with the geological evolution and tectonic processes in the study area the data are obtained from 78 broadband seismic stations owned by the earthquake department of the disaster and emergency management presidency for the period between 2008 and 2017 seven depth cross sections are taken along various segments of the east anatolian fault zone travel times of 53 099 phase readings 29 122 p phase and 23 977 s phase picks from 4249 high quality earthquake recordings are analysed to develop 3 d vp lithological and vp vs petrological models of the study area the resulting p wave velocities describe intrusive magmatic bodies sediment thickness and the structure of the basin the vp vs structures aid to limit the position of the faults areas of weakness and gas or liquid saturated units with regions of high pore pressure four main seismic crustal layers down to 40 km are determined the upper crust 0 8 km has vp 4 6 km s whereas in the middle crust 9 20 km a vp perturbation between 4 6 and 5 8 km s is observed in the lower crust 20 35 km vp changes from 5 9 to 7 3 km s and in the upper mantle layer below 36 km vp exceeds 7 4 km s in all cases seismic velocities are well resolved in the first 40 km tomograms are compatible with the geological characteristics of the region dominant high p velocity values are observed beneath the collision zone conrad discontinuity is detectable at 20 km depth while moho depth is observed to vary between 30 and 40 km in the study area

complex evolution of the erzincan basin eastern turkey abstract two new tectonic models are presented to explain the pull apart opening of the erzincan basin our field studies indicated that the erzincan basin is not a typical rhombic pull apart basin instead it has a rather complex single or two stage pull apart opening mechanism the basin was initially formed as a result of a 4 km wide releasing stepover and a 15 divergence angle between segments 1 and 2 of the north anatolian fault zone nafz along which the westward tectonic escape of the anatolian block has been taking place the single stage model refers to the partitioning of the transtensional deformation by coeval normal and strike slip displacements on parallel trending faults which remained since their initiation the two stage model infers that the basin opening was modified later by the formation of the left lateral ovacik fault which caused fragmentation of the anatolian block the two stage pull apart basin opening mechanism accounts for the observed geometry of the erzincan basin the present day geometry of the basin indicates that there had been 35 5 km of right lateral displacement along the nafz and 5 2 km of left lateral displacement along the ovacik fault

the erzincan turkey earthquake ms 6 8 of march 13 1992 and its aftershock sequence the erzincan strike slip earthquake of march 13 1992 ruptured a section of the north anatolian fault naf at the northern margin of the erzincan basin the focal depth of about 10 km was less than given by isc and neic erzincan and the surrounding villages were considerably damaged in the erzincan basin and in the neighbouring mountains a seismic network of ten stations was installed it was operating continuously from march 21 through june 16 1992 more than 3 000 aftershocks were recorded of which 505 could be located the spectral parameters of 394 and the fault plane solutions of 53 aftershocks were determined for the given region the frequency dependent coda q was derived as qc 122 f 0 68 the aftershock area increased with time reflecting the process of stress redistribution some events clustered in the immediate vicinity of the town of erzincan close to the epicentre of the main event and seem to trace the naf their source mechanism is similar to that of the main event strike slip about 150 aftershocks clustered in the southeastern part of the erzincan basin where a concentration of the events in a small volume of 5 5 3 km3 was observed the majority of fault plane solutions available for these aftershocks showed a normal faulting mechanism with an east west directed extension most of the aftershocks southeast of the basin clustered between two lineaments that were mapped by satellite images the p wave velocity below the erzincan basin derived from travel time residual analysis is lower compared to areas ne and sw of the basin three dimen sional stress modelling of the erzincan region qualitatively explains the occurrence of the aftershocks southeast of the basin the calculated displacement distribution which exhibits the north westward motion of the basin and tension at its southeastern margin caused by the erzincan earthquake is in agreement with derived fault plane solutions

tomographic pn velocity and anisotropy structure beneath the anatolian plateau eastern turkey and the surrounding regions an edited version of this paper was published by the american geophysical union agu copyright 2003 agu see also http www agu org pubs crossref 2003 2003gl017391 shtml http atlas geo cornell edu turkey publications al lazki et al 2003 htm

cassini imaging of jupiter s atmosphere satellites and rings the cassini imaging science subsystem acquired about 26 000 images of the jupiter system as the spacecraft encountered the giant planet en route to saturn we report findings on jupiter s zonal winds convective storms low latitude upper troposphere polar stratosphere and northern aurora we also describe previously unseen emissions arising from io and europa in eclipse a giant volcanic plume over io s north pole disk resolved images of the satellite himalia circumstantial evidence for a causal relation between the satellites metis and adrastea and the main jovian ring and information on the nature of the ring particles

three dimensional vp and vp vs structure of the upper crust in the erzincan basin eastern turkey 1 using aftershocks of the 13 march 1992 erzincan earthquake ms 6 8 three dimensional vp and vp vs velocity structure of the erzincan basin and its surroundings were modeled by local earthquake tomography travel times of body waves belonging to 1025 selected high quality events recorded by 58 temporary stations were inverted iteratively and simultaneously by using the simul2000 algorithm synthetic and resolution tests were performed to analyze the sensitivity of tomographic results and model parameterization the resulting 3 d vp and vp vs tomographic images show velocity anomalies related to geologic and tectonic structures beneath the erzincan basin while low vp anomalies down to 2 3 km depths are associated to thick neogene sediments deposited in the erzincan basin high vp anomalies indicate bed rocks and intrusive magmatic rocks beneath the mountain ranges vp vs anomalies are an important indicator of local tectonic structures and the physical mechanical and compositional variations in the rocks the low vp vs anomalies 1 7 observed at shallow depths 0 4 km track the main fault systems and thus the weakness zones in the basin the high vp vs anomalies 1 9 located between 4 and 6 km depth in the southeast of the erzincan basin may correspond to fluid saturation high pore pressure and carbonate content in the rock matrix the high vp vs ratios play an important role for increasing seismicity in this area because of the fluid saturation and the high pore pressure finally on the basis of the 3 d tomographic images basement of the erzincan basin deepens down to about 10 km depth and possesses an irregular and asymmetric shape the thick and unconsolidated sedimentary layer increases seismic risk to erzincan and other cities located on the basin as it magnifies ground motion caused by large earthquakes

dynamics of saturn s polar regions we analyze data retrieved by the imaging science system onboard the cassini spacecraft to study the horizontal velocity and vorticity fields of saturn s polar regions latitudes 60 90 n in june december 2013 and 60 90 s in october 2006 and july december 2008 including the northern region where the hexagonal wave is prominent with the aid of an automated two dimensional correlation algorithm we determine two dimensional maps of zonal and meridional winds and deduce vorticity maps we extract zonal averages of zonal winds providing wind profiles that reach latitudes as high as 89 5 in the south and 89 9 in the north wind measurements cover the intense polar cyclonic vortices that reach similar peak velocities of 150 m s 1 at 88 5 the hexagonal wave lies in the core of an intense eastward jet at planetocentric latitude 75 8 n with motions that become nonzonal at the hexagonal feature in the south hemisphere the peak of the eastward jet is located at planetocentric latitude 70 4 s a large anticyclone the south polar spot sps similar to the north polar spot nps observed at the voyager times 1980 1981 has been observed in images from april 2008 to january 2009 in the south polar region at latitude 66 1 close to the eastward jet the sps does not apparently excite a wave on the jet we analyze the stability of the zonal jets finding potential instabilities at the flanks of the eastward jets around 70 and we measure the eddy wind components suggesting momentum transfer from eddy motion to the westward jets closer to the poles

accurate hypocentre determination in the seismogenic zone of the subducting nazca plate in northern chile using a combined on offshore network the coupled plate interface of subduction zones commonly called the seismogenic zone has been recognized as the origin of fatal earthquakes a subset of the after shock series of the great antofagasta thrust type event 1995 july 30 mw 8 0 has been used to study the extent of the seismogenic zone in northern chile to achieve reliable and precise hypocentre locations we applied the concept of the minimum 1 d model which incorporates iterative simultaneous inversion of velocity and hypocentre parameters the minimum 1 d model is complemented by station corrections which are influenced by near surface velocity heterogeneity and by the individual station elevations by relocating mine blasts which were not included in the inversion we obtain absolute location errors of 1 km in epicentre and 2 km in focal depth a study of the resolution parameters ale and dspr documents the importance of offshore stations on location accuracy for offshore events based on precisely determined hypo centres we calculate a depth of 46 km for the lower limit of the seismogenic zone which is in good agreement with previous studies for this area for the upper limit we found a depth of 20 km our results of an aseismic zone between the upper limit of the seismogenic zone and the surface correlates with a detachment zone proposed by other studies the results are also in agreement with thermal studies for the antofagasta forearc region

patterns and processes of wood debris accumulation in the queets river basin washington field surveys in the 724 km 2 queets river basin on the west slope of the olympic mountains in nw washington reveal basin wide patterns of distinctive wood debris wd accumulations that arise from different mechanisms of wd recruitment hydraulic geometry and physical characteristics of wd individual pieces of wd in an accumulation or jam can be separated into key racked and loose members ten types of wd accumulations are identified based on the mode of recruitment and the orientation of key racked and loose debris relative to the channel axis although some types of wd accumulation have few geomorphic effects others form stable in stream structures that influence alluvial morphology at both subreach and reach length scales ranging from less than 1 to greater than 10 channel widths in the queets river stable accumulations of wd directly influence channel anabranching planform geometry flood plain topography and establishment of long term riparian refugia for old growth forest development the classification of wood debris accumulations in the queets river basin is based on physical observations that offer a template potentially applicable to other forested mountain regions d 2002 elsevier science b v all rights reserved

quantification of braided river channel change using archival digital image analysis historical archives of grey scale river channel imagery are extensive here we present and test a methodology to extract detailed quantitative topographic date from such imagery of sand bed rivers extracting elevation information from rivers is difficult as they are characterized by a low relative relief less than 4 m the area of interest may be spatially extensive e g active channel widths 500 m in large braided rivers the rate of change of surface elevation is generally low except in the vicinity of individual channel banks where the rate of change is very high there is the complication that comes from innundation and there may be an added complication caused by blockage of the field of view by vegetation here we couple archival photogrammetric techniques with image processing methods and test these for quantification of sand bed braided river dynamics illustrated for a 500 m wide 3 km long reach of the spouth sasketchewan river canada digitial photogrammetry was used to quantify dry areas and water edge elevations a methodology was then used to calibrate the special signature of inundated areas by combining established two media digital photogrammetric methods and image matching this allowed determination of detailed depth maps for inundated area and when combined with dry area data creation of depths detectable from sequential digital elevation models the result was a series of elevation models that demonstrate the potential for acquiring detailed and precise elevation data from any historical aerial imagery of rivers without needing associated calibration data provided that imagery is of the necessary scale to capture the features of interest we use these data to highlight several aspects of channel change on the south saskatchewan river including bar movement bank erosion and channel infilling

the crustal structure of the east anatolian plateau turkey from receiver functions an edited version of this paper was published by the american geophysical union agu copyright 2003 agu see also http www agu org pubs crossref 2003 2003gl018192 shtml http atlas geo cornell edu turkey publications zor et al 2003 htm

geophysical analysis of fault geometry and volcanic activity in the erzincan basin central turkey complex evolution of a mature pull apart basin abstract the erzincan basin is one of several neogene sedimentary basins developed by prolonged right lateral strike slip along the north anatolian fault zone nafz the intracontinental transform defining the present boundary between the eurasian plate to the north and accreted anatolian terranes to the south the basin has a strong asymmetry and young

large woody debris physical process and riparian forest development in montane river networks of the pacific northwest abstract we present a conceptual biogeomorphic model of riparian forest development in montane river networks the role of physical process in driving the structure composition and spatial distribution of riparian forests is examined we classify the drainage network into disturbance process based segments including 1 debris flow and avalanche channels 2 fluvial and debris flow channels and 3 fluvial channels riparian forests are shown to be significant in the development of channel morphology through the stabilization of active floodplains and as sources of large woody debris olwd lwd is operationally defined as wood 0 1 m diameter and 1 m length lwd plays a key role in the development of montane riparian forests lwd deposited in the active channel and floodplain provides sites for vegetation colonization forest island growth and coalescence and forest floodplain development riparian forest patterns parallel the distribution of hillslope and fluvial processes through the network riparian forest structure composition and spatial distribution through the network are driven by the major disturbance processes including 1 avalanches 2 debris flows and 3 flooding riparian forest patterns also reflect the action of lwd in the organization and development of forested floodplains in gravel bedded montane river networks the focus of our examples are montane river networks of the pacific northwest usa

parametrization of momentum transport by convection ii tests in single column and general circulation models diagnostics derived from cloud resolving model simulations in part i of this study relating to the vertical transport of horizontal momentum by convection are used to develop a parametrization of convective momentum transports for deep convection based upon the mass flux convection scheme discussed by gregory and rowntree the importance of cloud pressure gradients to the flow within the cloud is emphasised and a simple method of representing their effect is suggested the scheme is able to reproduce the fluxes derived from the cloud resolving model studies where cloud organization by the flow is unimportant inclusion of the parametrization in a version of the meteorological office unified model demonstrates that convective momentum transports play a large role in the momentum balance of the atmosphere generally simulation of the mean atmospheric circulation by the unified model is improved by the inclusion of such transports

constraints on saturn s tropospheric general circulation from cassini iss images abstract an automated cloud tracking algorithm is applied to cassini imaging science subsystem high resolution apoapsis images of saturn from 2005 and 2007 and moderate resolution images from 2011 and 2012 to define the near global distribution of zonal winds and eddy momentum fluxes at the middle troposphere cloud level and in the upper troposphere haze improvements in the tracking algorithm combined with the greater feature contrast in the northern hemisphere during the approach to spring equinox allow for better rejection of erroneous wind vectors a more objective assessment at any latitude of the quality of the mean zonal wind and a population of winds comparable in size to that available for the much higher contrast atmosphere of jupiter zonal winds at cloud level changed little between 2005 and 2007 at all latitudes sampled upper troposphere zonal winds derived from methane band images are 10 m s 1 weaker than cloud level winds in the cores of eastward jets and 5 m s 1 stronger on either side of the jet core i e eastward jets appear to broaden with increasing altitude in westward jet regions winds are approximately the same at both altitudes lateral eddy momentum fluxes are directed into eastward jet cores including the strong equatorial jet and away from westward jet cores and weaken with increasing altitude on the flanks of the eastward jets consistent with the upward broadening of these jets the conversion rate of eddy to mean zonal kinetic energy at the visible cloud level is larger in eastward jet regions 5 2 10 5 m 2 s 3 and smaller in westward jet regions 1 6 10 5 m 2 s 3 than the global mean value 4 1 10 5 m 2 s 3 overall the results are consistent with theories that suggest that the jets and the overturning meridional circulation at cloud level on saturn are maintained at least in part by eddies due to instabilities of the large scale flow near and or below the cloud level

stress history controls the spatial pattern of aftershocks case studies from strike slip earthquakes earthquake ruptures perturb stress within the surrounding crustal volume and as it is widely accepted now these stress perturbations strongly correlates with the following seismicity here we have documented five cases of the mainshock aftershock sequences generated by the strike slip faults from different tectonic environments of world in order to demonstrate that the stress changes resulting from large preceding earthquakes decades before effect spatial distribution of the aftershocks of the current mainshocks the studied mainshock aftershock sequences are the 15 october 1979 imperial valley earthquake mw 6 4 in southern california the 27 november 1979 khuli boniabad mw 7 1 the 10 may 1997 qa enat mw 7 2 and the 31 march 2006 silakhor mw 6 1 earthquakes in iran and the 13 march 1992 erzincan earthquake mw 6 7 in turkey in the literature we have been able to find only these mainshocks that are mainly characterized by dense and strong aftershock activities along and beyond the one end of their ruptures while rare aftershock occurrences with relatively lower magnitude reported for the other end of their ruptures it is shown that the stress changes resulted from earlier mainshock s that are close in both time and space might be the reason behind the observed aftershock patterns the largest aftershocks of the mainshocks studied tend to occur inside the stress increased lobes that were also stressed by the background earthquakes and not to occur inside the stress increased lobes that fall into the stress shadow of the background earthquakes we suggest that the stress shadows of the previous mainshocks may persist in the crust for decades to suppress aftershock distribution of the current mainshocks considering active researches about use of the coulomb stress change maps as a practical tool to forecast spatial distribution of the upcoming aftershocks for earthquake risk mitigation purposes in near real time it is further suggested that the background mainshocks along the neighbouring faults should be taken into account in producing the stress change maps for commenting on aftershock occurrences

crustal structure of the north anatolian and east anatolian fault systems from magnetotelluric data abstract magnetotelluric mt studies can map subsurface resistivity structure and have located zones of low resistivity high conductivity within major strike slip fault zones worldwide which have been interpreted as regions of elevated fluid content this study describes mt data from the eastern part of the north anatolian and the east anatolian fault systems nafs and eafs and presents the results of the first mt studies of these faults the inversion of the mt data produced 2 d resistivity models which showed that both fault systems are underlain by a broad low resistivity zone that extended into the lower crust however the resistivity beneath the east anatolian fault system was much lower than beneath the eastern part of the north anatolian fault system these conductors begin at a depth of 10 km not at the surface as on the central san andreas fault safs this difference is interpreted as being due to the fact that the eafs and nafs are young fault systems characterized in the upper crust by multiple fault traces as opposed to the safs that has evolved into a single through going fault different stages of the seismic cycle may also influence the resistivity structure although this is difficult to constrain without knowledge of time variations in resistivity structure at each location

saturn s northern hemisphere ribbon simulations and comparison with the meandering gulf stream voyager observations of saturn in 1980 81 discovered a wavy feature engirdling the planet at 47 n planetographic latitude its latitude coincides with that of an eastward jet stream which is the second fastest on saturn after the equatorial jet the 47 n jet s wavy morphology is unique among the known atmospheric jets on the gas giant planets since the voyagers it has been seen in every high resolution image of this latitude for over 25 years and has been termed the ribbon the ribbon has been interpreted as a dynamic instability in the jet stream this study tests this interpretation and uses forward modeling to explore the observed zonal wind profile s stability properties unforced initial value numerical experiments are performed to examine the nonlinear evolution of the jet stream parameter variations show that an instability occurs when the 47 n jet causes reversals in the potential vorticity pv gradient which constitutes a violation of the charney stern stability criterion after the initial instability development the simulations demonstrate that the instability s amplitude nonlinearly saturates to a constant when the eddy generation by the instability is balanced by the destruction of the eddies when the instability saturates the zonal wind profile approaches neutral stability according to arnol d s second criterion and the jet s path meanders in a ribbon like manner it is demonstrated that the meandering of the 47 n jet occurs over a range of tropospheric static stability and background wind speed the results here show that a nonlinearly saturated shear instability in the 47 n jet is a viable mechanism to produce the ribbon morphology observations do not yet have the temporal coverage to confirm the creation and destruction of eddies but these simulations predict that this is actively occurring in the ribbon region similarities exist between the behaviors found in this model and the dynamics of pv fronts studied in the context of meandering western boundary currents in earth s oceans in addition the simulations capture the nonlinear aspects of a new feature discovered by the cassini visual and infrared mapping spectrometer vims the string of pearls which resides in the equatorward tip of the 47 n jet the explicit planetary isentropic coordinate epic model is used herein

one dimensional thermal modeling of the eastern pontides orogenic belt ne turkey the eastern pontides orogenic belt is one of the most complex geodynamic settings in the alpine himalayan belt due to the lack of systematical geological and geophysical data in this study 1d crustal structure and p wave velocity distribution obtained from gravity modeling and seismological data in the area has been used for the development of the thermal model of the eastern pontides orogenic belt the computed temperature depth profiles suggest a temperature of 590 60 c at a moho depth of 35 km indicates the presence of a brittle ductile transition zone this temperature value might be related to water in the subducted crust of the tethys oceanic lithosphere the curie temperature depth value of 29 km which may correspond to the crustal magma chambers is found 5 7 km below the moho depth surface heat flow density values vary from 66 5 and 104 7 mw m 2 high mantle heat flow density value of 48 mw m 2 is obtained for the area should be related to melting of the lithospheric mantle caused by upwelling of asthenosphere

seismicity in the rotorua and kawerau geothermal systems taupo volcanic zone new zealand based on improved velocity models and cross correlation measurements abstract we analyze earthquakes occurring in and around the rotorua and kawerau geothermal systems taupo volcanic zone new zealand the two data sets contain 504 and 1875 shallow 20 km deep earthquakes respectively and span the 21 year period between 1984 and 2004 the arrival time data for these earthquakes are first used to calculate 1 d p and s wave seismic velocity models and accompanying station correction terms for both areas in order to address the non uniqueness of the joint hypocenter velocity model estimation problem we analyze suites of 1000 velocity models computed from random initial models the final velocity models are well constrained particularly at depths between 4 and 15 km and consistent with the results obtained in previous seismic refraction studies of the central taupo volcanic zone using a combination of cross correlation derived and catalog based arrival times we relocate subsets of the rotorua and kawerau data sets in rotorua the relocated earthquakes cluster near the geothermally active parts of rotorua city and beneath the mount ngongotaha rhyolite dome earthquake clusters and alignments reveal seismogenic structures in the mid crust whose positions and geometries are consistent with previously published fault mechanisms and known near surface faults in kawerau the earthquakes within the geothermal field align along northeast trending lineations consistent with the predominant alignment of surface mapped faults in the area

geophysical images of the north anatolian fault zone in the erzincan basin eastern turkey and their tectonic implications the collision between the arabian and eurasian plates in eastern turkey causes the anatolian block to move westward the north anatolian fault naf is a major strike slip fault that forms the northern boundary of the anatolian block and the erzincan basin is the largest sedimentary basin on the naf in the last century two large earthquakes have ruptured the naf within the erzincan basin and caused major damage m s 8 0 in 1939 and m s 6 8 in 1992 the seismic hazard in erzincan from future earthquakes on the naf is significant because the unconsolidated sedimentary basin can amplify the ground motion during an earthquake the amount of amplification depends on the thickness and geometry of the basin geophysical constraints can be used to image basin depth and predict the amount of seismic amplification in this study the basin geometry and fault zone structure were investigated using broadband magnetotelluric mt data collected on two profiles crossing the erzincan basin a total of 24 broadband mt stations were acquired with 1 2 km spacing in 2005 inversion of the mt data with 1d 2d and 3d algorithms showed that the maximum thickness of the unconsolidated sediments is 3 km in the erzincan basin the mt resistivity models show that the northern flanks of the basin have a steeper dip than the southern flanks and the basin deepens towards the east where it has a depth of 3 5 km the mt models also show that the structure of the naf may vary from east to west along the erzincan basin

saturn s zonal wind profile in 2004 2009 from cassini iss images and its long term variability abstract five years of cassini imaging science subsystem images from 2004 to 2009 are analyzed in this work to retrieve global zonal wind profiles of saturn s northern and southern hemispheres in the methane absorbing bands at 890 and 727 nm and in their respective adjacent continuum wavelengths of 939 and 752 nm a complete view of saturn s global circulation including the equator at two pressure levels in the tropopause 60 mbar to 250 mbar with the mt filters and in the upper troposphere from 350 mbar to 500 mbar with the cb filter set is presented both zonal wind profiles available at the supplementary material section show the same structure but with significant differences in the peak of the eastward jets and the equatorial region including a region of positive vertical shear symmetrically located around the equator between the 10 c

one dimensional crustal structure of the erzincan basin eastern turkey and relocations of the 1992 erzincan earthquake ms 6 8 aftershock sequence abstract in this study one dimensional 1 d p and s wave velocity structures of upper crust in the erzincan basin and precise hypocentre locations of aftershocks of 13 march 1992 erzincan earthquake ms 6 8 have been determined by using 1 d inversion algorithm velest and relocation algorithm hyp2000 interactively 22 291 p and 10 192 s arrival times of 1561 aftershocks recorded at 58 temporary stations have been used six layers have been defined within upper 20 km of the crust in the uppermost crust about 2 km thick sedimentary cover of the erzincan basin has very low p wave velocity as well as low vp vs ratio the p wave velocity reaches 6 3 km s at 7 km depth with an increasing gradient a thick crustal layer with a p wave velocity of 6 9 km s has been defined in the 7 20 km depth range several tests have been applied to check the stability of the velocity structure and the accuracy of the aftershock locations the general geometry of the aftershock distribution given by previous studies has not been drastically changed but more accurate aftershock locations have provided evidences for more reliable correlation to tectonic features and clues for new proposals on the recent deformation examination of well constrained aftershock cluster between pulumur and the southeast of the erzincan basin as well as very recent local seismic activity after 27 january 2003 pulumur earthquake ms 6 0 imply that a new antithetic fault activity to the north anatolian fault naf zone similar to the ovacik fault and the avcidag fault has developed the yedisu fault segment naf 1 of the naf displays relatively inactive character as defined in the previous studies

dynamics of saturn s great storm of 2010 2011 from cassini iss and rpws saturn s quasi periodic planet encircling storms are the largest convecting cumulus outbursts in the solar system the last eruption was in 1990 sanchez lavega a 1994 chaos 4 341 353 a new eruption started in december 2010 and presented the first ever opportunity to observe such episodic storms from a spacecraft in orbit around saturn fischer g et al 2011 nature 475 75 77 sanchez lavega a et al 2011 nature 475 71 74 fletcher l n et al 2011 science 332 1413 here we analyze images acquired with the cassini imaging science subsystem iss which captured the storm s birth evolution and demise in studying the end of the convective activity we also analyze the saturn electrostatic discharge sed signals detected by the radio and plasma wave science rpws instrument the storm s initial position coincided with that of a previously known feature called the string of pearls sops at 33 n planetocentric latitude intense cumulus convection at the westernmost point of the storm formed a particularly bright head that drifted at 26 9 0 8 m s 1 negative denotes westward motion on january 11 2011 the size of the head was 9200 km and up to 34 000 km in the north south and east west dimensions respectively rpws measurements show that the longitudinal extent of the lightning source expanded with the storm s growth the storm spawned the largest tropospheric vortex ever seen on saturn on january 11 2011 the anticyclone was sized 11 000 km by 12 000 km in the north south and east west directions respectively between january and september 2011 the vortex drifted at an average speed of 8 4 m s 1 we detect anticyclonic circulation in the new vortex the vortex s size gradually decreased after its formation and its central latitude shifted to the north the storm s head moved westward and encountered the new anticyclone from the east in june 2011 after the head vortex collision the rpws instrument detected that the sed activities became intermittent and declined over 40 days until the signals became undetectable in early august in late august the sed radio signals resurged for 9 days the storm left a vast dark area between 32 n and 38 n latitudes surrounded by a highly disturbed region that resembles the mid latitudes of jupiter using iss images we also made cloud tracking wind measurements that reveal differences in the cloud level zonal wind profiles before and after the storm

the erzincan earthquake of 13 march 1992 in eastern turkey the 13 march 1992 erzincan earthquake m 6 8 occurred in the eastern half of the erzincan basin the largest aftershock took place near pulumur on 15 march 1992 no clear surface breaks were observed although teleseismic studies suggested that it was a strike slip earthquake striking parallel to the north anatolian fault with a focus of approximately 10 2 km depth 30 km rupture length 95 cm of slip and a 1 16 1026 dyn cm seismic moment the aftershock distribution concentrated at an area of the intersection between the north anatolian fault and the ovacik fault these results indicate that the previously suggested seismic gap along the north anatolian fault east of erzincan still remains unruptured

cassini imaging of saturn southern hemisphere winds and vortices high resolution images of saturn s southern hemisphere acquired by the cassini imaging science subsystem between february and october 2004 are used to create maps of cloud morphology at several wavelengths to derive zonal winds and to characterize the distribution frequency size morphology color behavior and lifetime of vortices nonequatorial wind measurements display only minor differences from those collected since 1981 and reveal a strong prograde flow near the pole the region just southward of the velocity minimum at 40 7 s is especially active containing numerous vortices some generated in the proximity of convective storms the two eastward jets nearest the pole display periodicity in their longitudinal structure but no direct analogs to the northern hemisphere s polar hexagon or ribbon waves were observed characteristics of winds and vortices are compared with those of saturn s northern hemisphere and jupiter s atmosphere

the seismic velocity and fault structure of the erzincan basin turkey using local earthquake tomography summary we present a detailed 3 d seismic velocity model for the upper crust beneath the erzincan basin using tomographic inversion applied to the bodywave arrivals of the 1992 march 13 erzincan earthquake ml 6 9 aftershock sequence high quality digital data collected by various institutions is used consisting of 1240 hypocentres with rms errors less than 0 10 s recorded by 25 stations on average this provides a total of approximately 21 000 p and 10 000 s arrival times the final solution is well constrained and reveals sharp boundaries bordering the basin the shape of the basin is found to be deeper on the north and narrower at the eastern border the velocity contrast related to the basin extends down to a depth of 3 km but is hardly perceptible at 6 km and completely disappears at 9 km the thickness of low velocity unconsolidated soft sediments vp 2000 m s 1 is estimated to be shallower than 3 km the hypocentres were relocated using the inferred 3 d model and correlated with the fault segments that were observed in field studies in addition to the main segment of the north anatolian fault naf on the north of the basin we identified a secondary faulted zone located along the southern border of the basin and merging with the pulumur fault zone we observed that this southern zone has a limited extension towards east 20 km and therefore played only a minor role in the evolution of the basin despite the complex interaction between the north anatolian fault the ovacik fault and the pulumur fault zone it is clear that the erzincan basin has developed predominantly by the pull apart mechanism we conclude that the main continuation of naf to the east is the branch on the north following the euphrates valley and constitutes locally the primary seismic hazard factor

reconstructing the development of sampled sites on fluvial island surfaces of the tagliamento river italy from historical sources in parallel with research on surface sediment characteristics of evolving island features patches along an island braided reach of the tagliamento river italy the present research reconstructed the development of the sampled sites using historical information coupled with field measurements since any field sediment sampling programme inevitably focuses on small areas of the order of a few metres the historical sources were assessed bearing in mind their spatial resolution and geographical accuracy in relation to the size of the sampled sites and the information they could provide regarding the historical evolution of those sites the analysis combined four sources of information i river stage records revealed flood events that had the potential to reset bar surfaces and float in wood and seeds to initiate vegetation colonization ii oblique ground photographs identified areas of the river s active corridor where riparian vegetation colonization appeared to have been initiated by specific flood events iii dendrochronology was used to estimate the age of sampled sites iv field measured geographical locations of the sampled sites were combined with historical vertical areal imagery to further establish sampling site age and changes in vegetation cover from 1944 to 2012 a chronosequence of sampled sites 0 2 8 12 40 years was established vegetation colonization and island development showed a statistically significant development trajectory among sites of each age across the 40 year period following formative floods in 1965 1966 2000 2004 and a flow pulse in 2010 the trajectory progressed through pioneer and building island stages until vegetated areas became part of established islands evidence from the younger sites indicates that the pioneer island phase lasts up to eight years evidence from the oldest site indicates a building island phase lasting a maximum of 30 years but probably a lot less copyright 2014 john wiley sons ltd

lithospheric structure of the arabian and eurasian collision zone in eastern turkey from s wave receiver functions summary crustal and upper mantle seismic discontinuities beneath eastern turkey are imaged using teleseismic s to p converted phases three crustal phases are observed the moho with depth ranging between 30 and 55 km indicating variable tectonic regimes within this continental collision zone an upper crustal discontinuity at approximately 10 km depth and various crustal low velocity zones possibly associated with recent quaternary volcanism imaging of the upper mantle is complicated by the 3 d geometry of the region in particular due to the bitlis zagros suture zone however several upper mantle s to p converted phase are identified as being the signature of the lithosphere asthenosphere boundary lab the inferred lab for the eastern anatolian accretionary complex indicates that eastern turkey has an anomalously thin between 60 and 80 km lithosphere which is consistent with an oceanic slab detachment model the observed lab phases for the arabian shield and iranian plateau indicate that lithospheric thickness for these stable regions is on the order of 100 to 125 km thick which is typical of continental margins

atmospheric dynamics of saturn s 2010 giant storm great white spot a rare planet encircling storm raged on saturn in 2010 2011 analyses of high resolution spacecraft imagery and numerical modelling reveal a dynamic storm head powered by sustained convection in the zonal flow of saturn s atmosphere

cloud tracked winds from pioneer venus ocpp images abstract analysis of ultraviolet image sequences obtained from the pioneer venus orbiter cloud photopolarimeter and covering five 80 day periods from 1979 1985 provides the first climatological description of the cloud top circulation on venus the average zonal winds can be characterized as a 5 day retrograde rotation of the whole cloud level atmosphere with weak jets at middle to high latitudes both the midlatitude and equatorial zonal winds vary by about 5 8 m s 1 over time spans of 1 6 years the average meridional circulation is poleward in both hemispheres up to at least 60 latitude consistent with the presence of a thermally direct hadley circulation associated with the clouds the strength of the hadley circulation also varies with time four wave modes are clearly identified a diurnal solar tide a semi diurnal solar tide a 4 day equatorial wave and a 5 day midlatitude wave the semidiurnal tide appears to have an amplitude of about 5 m s 1 and to be approximately constant with time

contribution to understanding the historical evolution of meandering rivers using dendrochronological methods example of the mala panew river in southern poland the mala panew is a meandering river that flows 20 km through a closed forest during times of high discharge the riverbed and floodplain are transformed under the influence of riparian trees the changes provide the opportunity to measure the intensity of erosion and sediment accumulation based on tree ages the dating of coarse woody debris cwd in the riverbed and the dating of eccentric growth of tilting trees and exposed roots the bed and floodplain in reaches of the mala panew river with low banks were greatly altered as a result of long periods of flooding between 1960 and 1975 banks were undercut during these floods and black alders tilted those parts of alder crowns or stems which tilt and sink generate small sand shadows when erosion is intensive alder clumps are undercut from concave banks and become mid channel islands while on the other side of the channel meandering bar levels are created the reaches with higher banks were altered by large floods especially in 1985 and 1997 the concave banks are undercut and sediment with cwd is deposited within the riverbed forming sand shadows behind the cwd copyright 2006 john wiley sons ltd