litho1 0 an updated crust and lithospheric model of the earth we present the litho1 0 model which is a 1 tessellated model of the crust and uppermost mantle of the earth extending into the upper mantle to include the lithospheric lid and underlying asthenosphere the model is parameterized laterally by tessellated nodes and vertically as a series of geophysically identified layers such as water ice sediments crystalline crust lithospheric lid and asthenosphere litho1 0 is created by constructing an appropriate starting model and perturbing it to fit high resolution surface wave dispersion maps love and rayleigh group and phase over a wide frequency band 5 40 mhz we examine and discuss the model with respect to key lithospheric parameters such as average crustal velocity crustal thickness upper mantle velocity and lithospheric thickness we then compare the constructed model to those from a number of select studies at regional and global scales and find general consistency it appears that litho1 0 represents a reasonable starting model of the earth s shallow structure crust and uppermost mantle for the purposes in which these models are used such as traveltime tomography or in efforts to create a 3 d reference earth model the model matches surface wave dispersion over a frequency band wider than the band used in the inversion there are several avenues for improving the model in the future by including attenuation and anisotropy as well as making use of surface waves at higher frequency

the deep structure of the north anatolian fault zone abstract multi scale full waveform inversion of complete continental and regional scale seismograms reveals the crustal and upper mantle signature of the north anatolian fault zone which shapes the neotectonics of turkey and the eastern mediterranean within the crust the fault zone is mostly bounded by several high velocity blocks suggesting that it developed along the edges of continental fragments with high rigidity below the crust the surface expression of the eastern and central parts of the north anatolian fault zone correlate with a pronounced low velocity band that extends laterally over 600 km around 100 km depth the low velocity band merges into the shallow anatolian asthenosphere thereby providing a link to the kirka afyon isparta volcanic field and the central anatolian volcanics we interpret the low velocity band beneath the north anatolian fault zone as the upper mantle expression of the tethyan sutures that formed 60 15 ma ago as a result of africa eurasian convergence the structurally weak suture facilitated the formation of the younger less than 10 ma crustal fault zone in this sense the north anatolian fault zone is not only a crustal feature but a narrow zone of weakness that extends into the upper mantle

paleomagnetism and neogene clockwise rotation of the northern cady mountains mojave desert of southern california the early to middle miocene hector formation of the northern cady mountains consists of about 400 m of syntectonic alluvial fan and volcaniclastic sediments deposited in the central mojave desert paleomagnetic samples were collected from 60 sites throughout this unit samples from each site were treated using both alternating field and thermal demagnetization these studies and isothermal remanent magnetization experiments indicate that the natural remanent magnetization nrm is complex and that characteristic directions can be carried in either high coercivity or continuous unblocking temperature spectra depending upon the sample a positive reversals test and concordant directions of the alternating field af and low and high temperature components suggest a stable magnetization although a unique magnetostratigraphic correlation to the time scale is difficult the section studied may represent chrons c6b to c5c after screening of individual components and calculation of site means using fisher statistics 48 of the original 60 sites were used to calculate an overall formation mean direction i e declination 18 6 inclination 45 4 95 6 0 using a 20 m y paleomagnetic pole for north america irving and irving 1982 the hector formation has undergone 20 6 7 6 r r of clockwise rotation around a vertical axis this amount of rotation is considerably less than reported for some early miocene rocks elsewhere in the mojave block least squares regression of the 48 site mean declinations versus stratigraphic position indicates no trend throughout the section suggesting that there was no syndepositional rotation of this unit the late cenozoic structural history of the mojave block is considerably more complex than was originally believed and currently available paleomagnetic data indicate that many blocks within this region have experienced different degrees of rotation there were at least two phases of tectonic rotation in this region 1 early miocene about 25 ma probably related to the initiation of extension within the mojave rift and 2 post middle miocene pliocene between about 16 ma to the present possibly related to movement along principal structural features such as the san andreas fault zone the exact timing of the younger phase of tectonic activity cannot be better constrained until paleomagnetic data become available for late cenozoic rocks within the mojave block

alternative rupture scaling relationships for subduction interface and other offshore environments abstract alternative fault rupture scaling relationships are developed for m w 7 1 9 5 subduction interface earthquakes using a new database of consistently derived finite fault rupture models from teleseismic inversion scaling relationships are derived for rupture area rupture length rupture width maximum slip and average slip these relationships apply width saturation for large magnitude interface earthquakes approximately m w 8 6 for which the physical characteristics of subduction zones limit the depth extent of seismogenic rupture and consequently the down dip limit of strong ground motion generation on average the down dip rupture width for interface earthquakes saturates near 200 km 196 km on average accordingly the reinterpretation of rupture area scaling for subduction interface earthquakes through the use of a bilinear scaling model suggests that rupture asperity area is less well correlated with magnitude for earthquakes m w 8 6 consequently the size of great magnitude earthquakes appears to be more strongly controlled by the average slip across asperities the sensitivity of the interface scaling relationships is evaluated against geographic region or subduction zone and average dip along the rupture interface to assess the need for correction factors although regional perturbations in fault rupture scaling could be identified statistical significance analyses suggest there is little rationale for implementing regional correction factors based on the limited number of interface rupture models available for each region fault rupture scaling relationships are also developed for intraslab within the subducting slab extensional outer rise and offshore strike slip environments for these environments the rupture width and area scaling properties yield smaller dimensions than interface ruptures for the corresponding magnitude however average and maximum slip metrics yield larger values than interface events these observations reflect both the narrower fault widths and higher stress drops in these faulting environments although expressing significantly different rupture scaling properties from earthquakes in subduction environments the characteristics of offshore strike slip earthquake ruptures compare similarly to commonly used rupture scaling relationships for onshore strike slip earthquakes electronic supplement table of rupture parameters

paleomagnetism of middle miocene volcanic rocks in the mojave sonora desert region of western arizona and southeastern california paleomagnetic directions have been obtained from 190 early to middle miocene 12 20 ma mafic volcanic flows in 16 mountain ranges in the mojave sonora desert region of western arizona and southeastern california these flows generally postdate early miocene tectonic deformation accommodated by low angle normal faults but predate high angle normal faulting in the region after detailed demagnetization experiments 179 flows yielded characteristic directions interpreted as original thermal remanent magnetizations trm because of the episodic nature of basaltic volcanism in this region the 179 flows yielded only 65 time distinct virtual geomagnetic poles vgps the angular dispersion of the 65 vgps is consistent with the angular dispersion expected for a data set that has adequately averaged geomagnetic secular variation the paleomagnetic pole calculated from the 65 cooling unit vgps is located at 85 5 n 108 9 within a 4 4 circle of 95 confidence this pole is statistically indistinguishable at 95 confidence from reference poles calculated from rocks of similar age in stable north america and from a paleomagnetic pole calculated from rocks of similar age in baja california the coincidence of paleomagnetic poles from the mojave sonora desert region with reference poles from the stable continental interior indicates that 1 significant vertical axis net tectonic rotations have not accompanied post middle miocene high angle normal faulting in this region 2 there has been no detectable post middle miocene latitudinal transport of the region and 3 long term nondipole components of the middle miocene geomagnetic field probably were no larger than those of the recent 0 5 ma geomagnetic field in contrast paleomagnetic data indicate vertical axis rotations of similar age rocks in the transverse ranges the eastern transverse ranges and the mojave block we speculate that a major structural discontinuity in the vicinity of the southeastward projection of the death valley fault zone separates western areas affected by vertical axis rotations from eastern areas that have not experienced such rotations

correlation of the peach springs tuff a large volume miocene ignimbrite sheet in california and arizona the peach springs tuff is a distinctive early miocene ignimbrite deposit that was first recognized in western arizona recent field studies and phenocryst analyses indicate that adjacent outcrops of similar tuff in the central and easten mojave desert may be correlative this proposed correlation implies that outcrops of the tuff are scattered over an area of at least 35 000 km2 from the western colorado plateau to barstow california and that the erupted volume allowing for posteruption crustal extension was at least several hundred cubic kilometres thus the peach springs tuff may be a regional stratigraphic marker useful for determining regional paleogeography and the time and extent of tertiary crustal extension

mesozoic paleomagnetism and northward translation of the baja california peninsula paleomagnetic data from cretaceous igneous and sedimentary rocks of the peninsular ranges and continental borderland of the baja california peninsula yield an average pole position of 83 n 344 e a95 3 4 suggesting that the peninsula as a whole has moved northward 11 and rotated 32 clockwise with respect to the north american craton since cretaceous time only a small portion of this movement is due to the neogene opening of the gulf of california results from stratified rocks giving both positive and negative fold tests are included in the average cretaceous pole the rocks that fail fold tests have been deformed and remagnetized by nearby intrusives that are only slightly younger unconnected directions from these sites closely match corrected directions from sites where the fold tests are positive oceanic rocks were also sampled in the continental borderland from upper triassic and upper jurassic tectonostratigraphic terranes which are apparently allochthonous with respect to the western baja peninsula and each other these oceanic rocks show magnetizations indicating low paleolatitudes although the hemisphere of origin is presently unknown the cretaceous rocks of the baja california peninsula may have originally formed adjacent to the now truncated continental margin along the northern middle america trench northward transport of the peninsula probably occurred by transcurrent faulting associated with oblique subduction of the farallon plate beneath western north america between late cretaceous and late miocene time

faulting associated with historical and recent earthquakes in the eastern mediterranean region summary this paper summarizes evidence for surface faulting in historical and recent earthquakes in the eastern mediterranean region and in the middle east such information is particularly important for studies of active tectonics and for palaeoseismology we have found 78 cases of faulting pre 1900 and 72 post 1900 some of which show that faults that have apparently been inactive this century had already ruptured before 1900 for some cases faulting could not have been predicted from 20th century activity and in others it could have been expected but has not been observed during the instrumental period the data are suycient to allow the derivation of relationships between magnitude and rupture length

slip segmentation and slow rupture to the trench during the 2015 mw8 3 illapel chile earthquake the 2015 mw8 3 illapel chile earthquake is the latest megathrust event on the central segment of that subduction zone it generated strong ground motions and a large up to 11 m runup tsunami which prompted the evacuation of more than 1 million people in the first hours following the event observations during recent earthquakes suggest that these phenomena can be associated with rupture on different parts of the megathrust the deep portion generates strong shaking while slow large slip on the shallow fault is responsible for the tsunami it is unclear whether all megathrusts can have shallow slip during coseismic rupture and what physical properties regulate this here we show that the illapel event ruptured both deep and shallow segments with substantial slip we resolve a kinematic slip model using regional geophysical observations and analyze it jointly with teleseismic backprojection we find that the shallow and deep portions of the megathrust are segmented and have fundamentally different behavior we forward calculate local tsunami propagation from the resolved slip and find good agreement with field measurements independently validating the slip model these results show that the central portion of the chilean subduction zone has accumulated a significant shallow slip deficit and indicates that given enough time shallow slip might be possible everywhere along the subduction zone

the july 20 2017 m6 6 kos earthquake seismic and geodetic evidence for an active north dipping normal fault at the western end of the gulf of gokova se aegean sea on july 20 2017 22 31 utc a strong mw 6 6 earthquake occurred at shallow depth between kos island greece and bodrum turkey we derive a co seismic fault model from joint inversion of geodetic data gnss and insar assuming that the earthquake can be modelled by the slip of a rectangular fault buried in an elastic and homogeneous half space the gnss observations constrain well most of the model parameters but do not permit to discriminate between south and north dipping planes however the interferograms produced from c band esa sentinel 1 data give a clear preference to the north dipping plane we also map surface motion away from the satellite along the turkish coast from bodrum towards the east which reached about 17 cm onshore islet karaada the best fit model is obtained with a 37 north dipping n283 e striking normal fault in agreement with the published moment tensor solutions the resolved slip vector is dominantly normal with a slight component of left lateral motion 15 the surface projection of the seismic fault outcrops in the gokova ridge area a well developed bathymetric feature inside the western gulf of gokova our geodetic model fits the pattern of the shallow north dipping aftershocks obtained from rigorous relocation of all available recordings in the region about 1120 events relocated mainshock is at 36 955 n 27 448 e depth at 9 2 km 0 5 km the relocated aftershocks also indicate clustering at both ends of the rupture and seismicity triggering mainly towards the east and the north within 2 weeks following the mainshock we also analysed regional gps data interseismic velocities and obtained an extension rate of 3 2 mm yr across the gokova rift along a direction n165 e

distribution of interseismic coupling along the north and east anatolian faults inferred from insar and gps data the north anatolian fault naf has produced numerous major earthquakes after decades of quiescence the mw 6 8 elazig earthquake january 24 2020 has recently reminded us that the east anatolia

rupture kinematics of 2020 january 24 mw 6 7 doganyol sivrice turkey earthquake on the east anatolian fault zone imaged by space geodesy

aegean tectonics strain localisation slab tearing and trench retreat abstract we review the geodynamic evolution of the aegean anatolia region and discuss strain localisation there over geological times from late eocene to present crustal deformation in the aegean backarc has localised progressively during slab retreat extension started with the formation of the rhodope metamorphic core complex eocene and migrated to the cyclades and the northern menderes massif oligocene and miocene accommodated by crustal scale detachments and a first series of core complexes mccs extension then localised in western turkey the corinth rift and the external hellenic arc after messinian times while the north anatolian fault penetrated the aegean sea through time the direction and style of extension have not changed significantly except in terms of localisation the contributions of progressive slab retreat and tearing basal drag extrusion tectonics and tectonic inheritance are discussed and we favour a model 1 where slab retreat is the main driving engine 2 successive slab tearing episodes are the main causes of this stepwise strain localisation and 3 the inherited heterogeneity of the crust is a major factor for localising detachments the continental crust has an inherited strong heterogeneity and crustal scale contacts such as major thrust planes act as weak zones or as zones of contrast of resistance and viscosity that can localise later deformation the dynamics of slabs at depth and the asthenospheric flow due to slab retreat also have influence strain localisation in the upper plate successive slab ruptures from the middle miocene to the late miocene have isolated a narrow strip of lithosphere still attached to the african lithosphere below crete the formation of the north anatolian fault is partly a consequence of this evolution the extrusion of anatolia and the aegean extension are partly driven from below asthenospheric flow and from above extrusion of a lid of rigid crust

pliocene early pleistocene history of the euphrates valley applied to late cenozoic environment of the northern arabian plate and its surrounding eastern turkey abstract the pliocene quaternary paleogeography of the euphrates river valley changed due to sinistral movements on the east anatolian fault zone eafz and the taurus ridge rise by movements on the south taurus thrust evidence of these changes is based on studies of the pliocene quaternary deposits of the euphrates river basin to the north and to the south of the taurus ridge and the late cenozoic deformation including offsets on the eafz combination of methods was used to date the pliocene quaternary deposits it includes geological and geomorphic analysis and correlation of sections determination of remanent magnetization paleontological and archaeological finds pollen analysis and k ar dating of volcanic rocks to the north of the taurus ridge the late miocene tectonic depressions were filled by lakes connected by braided streams in the early pliocene the euphrates and murat river valleys formed and the euphrates flew to the south westwards of its recent position via the graben like trough of the sultan suyu river valley and farther to the erikdere that are recent euphrates tributaries the flow was interrupted later because of some desiccation and rise of the taurus ridge the flow recommenced in the end gelasian early calabrian via the goksu cayi and erikdere valleys consecutively and was interrupted again at the end of calabrian 0 8 0 9 ma the euphrates waters found the recent way via the taurus ridge and the former upstream bottoms of the euphrates and its tributaries valleys became a vast upper terrace after this the taurus ridge rose by more than 330 m lower terraces were formed because of the tectonic uplift that was more intense to the north of the taurus ridge 0 13 0 16 mm year than to the south of it 0 1 mm year the new formed segment of the euphrates valley was offset on the eafz at 12 km that gives the slip rate of 13 15 mm year

the relative contribution of accretion shear and extension to cenozoic tectonic rotation in the pacific northwest large cenozoic clockwise rotations defined by paleomagnetic data are an established fact in the pacific northwest and many tectonic models have been proposed to explain them including 1 rotation of accreted oceanic microplates during docking 2 dextral shear between north america and northward moving oceanic plates to the west and 3 microplate rotation in front of an expanding basin and range province stratigraphic onlap relations and local structure indicate that microplate rotation during docking was not a major contributor to the observed rotations coast range structures basin and range extension and paleomagnetic data from middle miocene 15 ma coast range rocks indicate that dextral shear is responsible for at least 40 of the post 15 ma rotation of the coast range and that basin and range extension is responsible for the remainder reconstructions based on extrapolation of this ratio back to 37 and 50 ma are consistent with reconstructions based on paleomagnetic and stratigraphic relations in older rocks and suggest that dextral shear has been a significant contributor to rotation during most of tertiary time changes in the dextral shear rotation rate over the past 50 m y correlate directly with changes in the velocity of the farallon plate parallel to the coast and provide a strong argument for oblique subduction as the driving mechanism continental reconstructions incorporating shear may provide constraints on the rate of extension in the northernmost basin and range region and suggest 17 extension since 15 ma 39 since 37 ma and 72 since 50 ma near latitude 42 n

paleomagnetic evidence for neogene clockwise tectonic rotations in the central mojave desert california paleomagnetic directions from early miocene volcanic flows indicate that a large part of the central mojave desert has been tectonically rotated stratigraphic relations and isotopic ages suggest that two separate clockwise rotations have occurred an early miocene rotation of 50 15 6 is coincident in time and space with opening of the daggett extensional terrane a post early miocene rotation of 30 to 50 may have affected the alvord mountains and the immediate vicinity

paleomagnetism of the roskruge and gringo gulch volcanics southeast arizona paleomagnetic data were obtained from nine cooling units of the late cretaceous 72 ma roskruge volcanics and from 25 flows in the lower paleocene gringo gulch volcanics both from southeastern arizona alternating field demagnetization successfully erased the infrequent secondary components of magnetization the paleomagnetic pole position obtained from the roskruge volcanics is at 73 6 n 176 0 e with dp 6 2 and dm 8 8 the gringo gulch volcanics pole position is at 77 0 n 201 0 e with dp 1 2 and dm 1 7 in conjunction with other recently published paleocene and eocene paleomagnetic poles these data provide details of north american apparent polar wander during the laramide orogeny 80 to 40 ma an episode of rapid apparent polar wander from the cretaceous pole position in the bering strait to the eocene pole position near the present rotation axis occurred during that interval of time the initiation of this episode of apparent polar wander appears to be coincident with the major plate reorganizations which occurred at the onset of the laramide orogeny

aftershock study and seismotectonic implications of the 8 march 2010 kovancilar elazig turkey earthquake mw 6 1 1 a destructive earthquake mw 6 1 occurred on the northeast end of the palu segment of the east anatolian fault system eafs eastern turkey on 8 march 2010 the spatial distribution of aftershocks suggests that the palu segment does not terminate to the east of palu town but extends in the n50 e direction where it has produced a 30 km right stepover aftershock depths indicate a seismogenic brittle zone of about 15 km depth the stress changes on the segments due to recorded events might have loaded more than 0 5 bars of stress on the ne end of the palu segment and the sw end of the goynuk segment therefore a future earthquake on both segments may occur sooner than was expected before the occurrence of the mw 6 1 earthquake on 8 march 2010

fault plane modelling of the 2003 august 14 lefkada island greece earthquake based on the analysis of envisat sar interferograms abstract on 2003 august 14 a mw 6 2 earthquake occurred offshore the lefkada island in the eastern ionian sea one of the most seismically active areas in europe the earthquake caused extended damages in the island and a number of ground failures especially along the north western coast seven ascending envisat asar images are used to process six co seismic interferograms the roi pac package is used for interferogram generation with the srtm dem applied in a two pass method the formation of the co seismic pairs is limited due to the existence of one pre seismic image only dense vegetation is covering the island which is an obstacle in getting good coherence since c band images are used nevertheless ground deformation of 56 mm two fringes in the line of sight of the satellite is detected in all six co seismic interferograms by inversion of the data from the observed fringes a best fitting model of the activated fault is calculated assuming a dislocation in an elastic half space the inferred fault is a pure dextral strike slip fault dipping 59 5 eastward 16 2 km long and 10 2 km wide it is located north of the fault of the mw 6 5 2015 november 17 earthquake and a 10 15 km gap remains between the two faults the 2003 fault does not reach the surface and its upper edge is at a depth of 3 5 1 km no evidence is found of slip south of the lefkada island as suggested by some seismological studies

kinematic earthquake source inversion and tsunami runup prediction with regional geophysical data rapid near source earthquake source modeling relying only on strong motion data is limited by instrumental offsets and magnitude saturation adversely affecting subsequent tsunami prediction seismogeodetic displacement and velocity waveforms estimated from an optimal combination of high rate gps and strong motion data overcome these limitations supplementing land based data with offshore wave measurements by seafloor pressure sensors and gps equipped buoys can further improve the image of the earthquake source and prediction of tsunami extent inundation and runup we present a kinematic source model obtained from a retrospective real time analysis of a heterogeneous data set for the 2011 mw9 0 tohoku oki japan earthquake our model is consistent with conceptual models of subduction zones exhibiting depth dependent behavior that is quantified through frequency domain analysis of slip rate functions the stress drop distribution is found to be significantly more correlated with aftershock locations and mechanism types when off shore data are included the kinematic model parameters are then used as initial conditions in a fully nonlinear tsunami propagation analysis notably we include the horizontal advection of steeply sloping bathymetric features comparison with post event on land survey measurements demonstrates that the tsunami s inundation and runup are predicted with considerable accuracy only limited in scale by the resolution of available topography and bathymetry we conclude that it is possible to produce credible and rapid kinematic source models and tsunami predictions within minutes of earthquake onset time for near source coastal regions most susceptible to loss of life and damage to critical infrastructure regardless of earthquake magnitude

magnitude scaling of the near fault rupture directivity pulse abstract current ground motion models all assume monotonically increasing spectral amplitude at all periods with increasing magnitude however near fault recordings from recent earthquakes confirm that the near fault fault normal forward rupture directivity velocity pulse is a narrow band pulse whose period increases with magnitude this magnitude dependence of the period of the near fault pulse is expected from theory because the period of the pulse is related to source parameters such as the rise time duration of slip at a point on the fault and the fault dimensions which generally increase with magnitude this magnitude dependence of the pulse period causes the response spectrum to have a peak whose period increases with magnitude such that the near fault ground motions from smaller earthquakes may exceed those of larger earthquakes at intermediate periods around 1 s this paper presents preliminary equations relating the period of the fault normal component of the forward rupture directivity velocity pulse to the earthquake magnitude and a preliminary model for the acceleration response spectra of near fault fault normal ground motions that includes the magnitude dependence of the period of the response spectral peak

the geodynamics of the aegean and anatolia introduction the complexity of the plate interactions and associated crustal deformation in the eastern mediterranean region is reflected in many destructive earthquakes that have occurred throughout its recorded history many of which are well documented and intensively studied the eastern mediterranean region including the surrounding areas of western turkey and greece is indeed one of the most seismically active and rapidly deforming regions within the continents fig 1 thus the region provides a unique opportunity to improve our understanding of the complexities of continental tectonics in an actively collisional orogen the major scientific observations from this natural laboratory have clearly been helping us to better understand the tectonic processes in active collision zones the mode and nature of continental growth and the causes and distribution of seismic volcanic and geomorphological events e g tsunamis and their impact on societal life and civilization the tectonic evolution of the eastern mediterranean region is dominated by the effects of subduction along the hellenic aegean arc and of continental collision in eastern turkey anatolia and the caucasus northward subduction of the african plate beneath western turkey and the aegean region is causing extension of the continental crust and volcanism in the overlying aegean extensional province eastern turkey has been experiencing crustal shortening and thickening as a result of northward motion of the arabian plate relative to eurasia and the attendant postcollisional magmatism taymaz et al 1990 1991a b mcclusky et al 2000 2003 dilek pavlides 2006 and references therein fig 2 the resulting combination of forces the pull from the subduction zone to the west and push from the convergent zone to the east is causing the turkish plate to move southwestward bounded by strike slip fault zones the north anatolian fault zone nafz to the north and the east anatolian fault zone eafz to the south interplay between dynamic effects of the relative motions of adjoining plates thus controls large scale crustal deformation and the associated seismicity and volcanism in anatolia and the aegean region taymaz et al 2004

some thoughts on the use of insar data to constrain models of surface deformation noise structure and data downsampling repeat pass interferometric synthetic aperture radar insar provides spatially dense maps of surface deformation with potentially tens of millions of data points here we estimate the actual covariance structure of noise in insar data we compare the results for several independent interferograms with a large ensemble of gps observations of tropospheric delay and discuss how the common approaches used during processing of insar data affects the inferred covariance structure motivated by computational concerns associated with numerical modeling of deformation sources we then combine the data covariance information with the inherent resolution of an assumed source model to develop an efficient algorithm for spatially variable data resampling or averaging we illustrate these technical developments with two earthquake scenarios at different ends of the earthquake magnitude spectrum for the larger events our goal is to invert for the coseismic fault slip distribution for smaller events we infer the hypocenter location and moment we compare the results of inversions using several different resampling algorithms and we assess the importance of using the full noise covariance matrix

neogene clockwise tectonic rotation of the eastern transverse ranges california suggested by paleomagnetic vectors results from a paleomagnetic study of neogene volcanic rocks situated within and around the pinto basin region of the eastern transverse ranges suggest that the ranges have undergone a clockwise tectonic rotation of 41 4 7 7 since late miocene time both normal and reversed polarities are observed and inclination data indicate no significant flattening the rotation was accompanied by progressive sinistral slip on the several east west trending faults which bound and transect the eastern transverse ranges a computation using the observed amount of cumulative left slip on the east west trending faults of the eastern transverse ranges 50 km and the spacing between the pinto mountain and salton creek faults which bound the region 70 km indicates that 35 of clockwise rotation is required which roughly agrees with the paleomagnetic data removal of the eastern transverse ranges rotation in a reconstruction shows that the distributed dextral shear across the mojave desert region to the north must have been on the order of 100 km since late miocene time from the results of this study we infer that crustal rotation of the eastern transverse ranges began later and is of less magnitude than that of the western transverse ranges

numerical simulation of 3 d mantle flow evolution in subduction zone environments in relation to seismic anisotropy beneath the eastern mediterranean region abstract seismic anisotropy is a key parameter in understanding subduction zone dynamics in relation to the recent deformation history it is usually controlled by the mantle flow patterns resulting from the dynamic interactions between a relatively dense subducting oceanic plate and the surrounding mantle a proper modelling of mantle flow in subduction systems helps our understanding of the seismic anisotropy source strength and evolution in time this study further examines shear wave splitting parameters one of the most well established measuring methods of seismic anisotropy and their anisotropy source based on 3 d geodynamic modelling applied to the eastern mediterranean sea and anatolia our model setting is chosen to be a first order representation of the present day tectonic setting as it consists of a deforming anatolian micro plate that is indented by slow moving african and arabian plates and an oceanic plate in between the retreat of the slab in the aegean region the alleged tear in the subducting slab close to the cyprus trench and the break off in the slab in eastern anatolia are considered in our modelling study in order to further explore their influence on mantle flow and splitting parameters the synthetically calculated fast polarization directions fpds mostly showed a reasonable matching with those inferred from previous seismological observations that are mainly sks splitting measurements regions of fpd similarities between synthetic and observed shear waves mostly indicate n s to ne sw orientations of fast shear waves which are parallel to the extension in the back arc region and in general perpendicular to the trench the pattern of fpds seems to be more complex nearby the trench our modelling results suggest that the development of a tear in the african slab and the detachment occurring within the arabian plate break off appear to have a significant influence on the fpds due to stronger mantle flow through the slab windows the mantle flow through the tear close to cyprus and the break off in the east can be identified clearly despite their recent appearances a circular pattern around the edges of the slab can be observed as well as disruptions of the overall general fast polarization direction due to the flow through the tear

the 2020 mw 6 8 elazig turkey earthquake reveals rupture behavior of the east anatolian fault the 2020 mw 6 8 elazig earthquake was the largest along the eastern anatolian fault eaf in over a century and so provides valuable insights into its rupture behavior because the eaf is of low to

the utility of gnss for earthquake early warning in regions with sparse seismic networks abstract real time global navigation satellite systems gnss data are on their way to being well integrated into earthquake early warning eew systems the strength of gnss data lies in the resolution of large dynamic and static displacements because of the limits in precision gnss data alone cannot resolve small ground displacements due to for instance p waves therefore their use is currently limited to refining early warnings with more precise earthquake characteristics such as magnitudes or ground motion predictions here we analyze 1 hz global positioning system gps data from the 24 january 2016 m w 7 1 iniskin earthquake which ruptured 125 km under cook inlet in alaska to motivate the inclusion of gnss derived s wave measurements into the trigger algorithms of eew systems in regions lacking dense early warning instrumentation networks we derive a relationship between earthquake depth and distance to help determine whether gnss s wave observations could expedite warnings to specific locations because the iniskin earthquake was deep by the time the s wave reached the surface the p wave had already been observed over a wide region limiting the potential for unique contributions from gnss data to this event for the same earthquake occurring near the surface however s waves derived from gnss data have the potential to increase the warning time regardless of the depth the iniskin earthquake is an excellent example of the utility of gnss in rapidly assessing the magnitude improving predictions of ground shaking and estimating the area of impact for the earthquake

structure and development of giant carbonate mounds at the sw and se rockall trough margins ne atlantic ocean abstract high resolution seismic reflection profiling carried out in 1997 1999 showed that giant carbonate mounds occur between 500 and 1200 m water depth along both the se and sw margins of rockall trough the mounds rise 5 300 m above the surrounding seafloor and have diameters at their bases of up to 5 km buried mounds at relatively shallow depths below the seafloor are also found both individual and complex clusters of mounds can be recognized smaller and individual sometimes buried mounds are found at the upper slope on the sw rockall trough margin higher steeper and individual mounds are found deeper downslope 900 1100 m at the middle slope the mounds merge into a complex structure and form complex clusters with a very irregular upper surface and an apparent lack of internal reflectors 600 1000 m depth initial results of high resolution 3d seismic profiling at 30 m line spacing in august 2000 in two boxes of 750 m 14 5 km covering a small central part of the sw rockall trough mound area indicate two stages of mound development here the latest probably of pliocene holocene age this age based on the presence of a regionally recognizable unconformity below the mounds is also assumed for the mounds of the se rockall trough porcupine bank margin

paleomagnetism and the motion of large and small plates the focus of paleomagnetic research during past decades has varied greatly the first generation in paleomagnetism might be defined as beginning with the pioneering studies aimed at discovering whether the geomagnetic field has been a reliable reference frame for measuring and timing continental displacements an enormous effort followed in the form of individual paleomagnetic studies of cratonic rocks culminating with the construction of apw apparent polar wander paths for the continents which could be used to test paleogeographic reconstructions coupled with parallel research in marine geophysics and geology the refined apwp which result from this effort have helped to develop a reasonable first order history of cenozoic mesozoic paleogeography for the major plates

rupture process of the 2004 parkfield earthquake from near fault seismic waveform and geodetic records 1 the 28 september 2004 parkfield earthquake arguably the best recorded earthquake ever allows for detailed investigation of finite source models and their resolution we have developed finite source models using gps and interferometric synthetic aperture radar geodetic data and seismic strong motion waveform data f 0 5 hz both independently and combined the preferred model shows that the rupture is predominantly unilateral to the nw with a small component to the se slip is concentrated into two primary patches one near the hypocenter and the other between 10 and 23 km to the nw within a narrow depth range 5 13 km the scalar seismic moment is 1 3 1018 n m mw 6 0 the overall rupture length is 23 km the peak slip is 0 45 m and the rupture velocity is 2 6 km s the average static stress drop obtained from the spatially distributed slip model is 2 3 mpa and peak values are 10 mpa a detailed sensitivity and resolution analysis shows that the recovered slip the average rupture velocity risetime and slip velocity are well resolved

temporary seismic quiescence se turkey summary the border zone that is the contact of the arabian plate with the three plates of turkey eurasia and iran to the north has been remarkably aseismic during this century by extending the period of observation backwards in time by a few centuries it is shown that this seismicity is atypical of the long term behaviour of the zone and due to a quiescent period in the activity of the area during the 20th century in turn this implies that short term data alone do not provide a reliable assessment of earthquake hazard

rapid modeling of the 2011 mw 9 0 tohoku oki earthquake with seismogeodesy 1 rapid characterization of finite fault geometry and slip for large earthquakes is important for mitigation of seismic and tsunamigenic hazards saturation of near source weak motion and problematic integration of strong motion data into displacements make this difficult in real time combining gps and accelerometer data to estimate seismogeodetic displacement waveforms overcomes these limitations by providing mm level three dimensional accuracy and improved estimation of coseismic deformation compared to gps only methods we leverage collocated gps and accelerometer data from the 2011 mw 9 0 tohoku oki japan earthquake by replaying them in simulated real time mode using a novel approach to account for fault finiteness we generate an accurate centroid moment tensor solution independently of any constraint on the slab geometry followed by a finite fault slip model the replay of gps and seismic data demonstrates that robust models could have been made available within 3 min of earthquake initiation

structure and deformation history of the bitlis suture near lake hazar southeastern turkey detailed mapping of the bitlis suture zone near lake hazar shows that it is composed of three tectonostratigraphic units which crop out as distinct north dipping thrust slices from south to north these are the puturge metamorphic complex the maden melange and the elazig igneous complex the puturge metamorphic complex consists of pre tertiary continental margin sediments metamorphosed to the greenschist facies during the campanian maastrichtian and deformed by four generations of structures these are in sequence 1 isoclinal folds and a transposition foliation 2 open folds crenulation cleavage and north dipping thrust faults 3 kink bands and 4 small displacement faults the maden melange represents middle eocene back arc basin sediments and volcanics metamorphosed to the greenschist facies and deformed by three generations of structures 1 a north dipping cleavage 2 kink bands and 3 small displacement faults the elazig igneous complex comprises an imbricated maastrichtian early eocene island arc and young marginal basin terrain thrust faults between units are north dipping listric and form a thin skinned system these features suggest the following deformational and tectonic history the puturge metamorphic complex was generated by isoclinal folding and metamorphism of sediments composing the arabian continental margin during campanian maastrichtian ophiolite obduction to the south the elazig arc developed on the deformed margin because of subsequent southward subduction of oceanic lithosphere the arc migrated to the north opening a back arc basin by the early eocene the back arc basin was filling with volcaniclastics of the maden melange and the elazig arc collided with a continent to the north during middle to late eocene convergence caused thrust stacking of the elazig maden and puturge complexes second generation deformation in the puturge complex and first generation deformation in the maden melange continued convergence with the arabian plate in the late miocene caused kink banding in the puturge and maden complexes since the late miocene this convergence has been accommodated by shortening and thickening along numerous internal faults

source characteristics of the 2015 m w 7 8 gorkha nepal earthquake and its m w 7 2 aftershock from space geodesy abstract on april 25 2015 a destructive m w 7 8 earthquake struck the capital of nepal kathmandu killing more than 8800 people and destroying numerous historical structures we analyze six coseismic interferograms from several satellites alos 2 sentinel 1 a and radarsat 2 as well as three dimensional displacements at six gps stations to investigate fault structure and slip distribution of the gorkha earthquake using a layered crustal structure the best fit slip model shows that the preferred dip angle of the mainshock fault is 6 3 5 and the major slip is concentrated within depths of 8 15 km the maximum slip of 6 0 m occurs at a depth of 11 km 70 km south east of the epicenter the coseismic rupture extends 150 km eastward of the epicentre with a cumulative geodetic moment of 7 8 10 20 nm equivalent to an earthquake of m w 7 84 we also investigate the m w 7 2 aftershock on 12 may 2015 using another three postseismic interferograms from alos2 radarsat 2 and sentinel 1 a the insar based best fit slip model of the largest aftershock implies that its major slip is next to the eastern lower end of the mainshock rupture with a similar maximum slip of 6 m at a depth of 13 km this study generates various coseismic geodetic measurements to determine the source parameters of the m w 7 8 gorkha earthquake and 12 may m w 7 2 afershock providing an additional chance to understand the local fault structure and slip extent

radar interferogram filtering for geophysical applications the use of sar interferometry is often impeded by decorrelation from thermal noise temporal change and baseline geometry power spectra of interferograms are typically the sum of a narrow band component combined with broad band noise we describe a new adaptive filtering algorithm that dramatically lowers phase noise improving both measurement accuracy and phase unwrapping while demonstrating graceful degradation in regions of pure noise the performance of the filter is demonstrated with sar data from the ers satellites over the jakobshavns glacier of greenland

systematic observations of the slip pulse properties of large earthquake ruptures in earthquake dynamics there are two end member models of rupture propagating cracks and self healing pulses these arise due to different properties of faults and have implications for seismic hazard rupture mode controls near field strong ground motions past studies favor the pulse like mode of rupture however due to a variety of limitations it has proven difficult to systematically establish their kinematic properties here we synthesize observations from a database of 150 rupture models of earthquakes spanning m7 m9 processed in a uniform manner and show the magnitude scaling properties of these slip pulses indicates self similarity further we find that large and very large events are statistically distinguishable relatively early at 15 seconds in the rupture process this suggests that with dense regional geophysical networks strong ground motions from a large rupture can be identified before their onset across the source region

source parameters of large earthquakes in the east anatolian fault zone turkey summary the east anatolian fault zone accommodates most of the motion between the arabian plate and the apparently little deforming interior of central turkey the direction of overall slip across this zone is crucial to the determination of the slip rate on the north anatolian fault we use long period p and sn waveforms to determine the source parameters of the four largest earthquakes that occurred in or near the east anatolian fault zone in the last 35 years only one of these actually involved left lateral strike slip motion on a ne sw fault but the other three and the nearby 1975 lice earthquake all had steeply dipping nodal planes with a nnw strike if these were the auxiliary planes then all the earthquakes had a slip vector direction within about 10 of 063 if this direction represents the arabia turkey motion then the slip rate on the north anatolian fault must be in the range 31 to 48 mm yr with a probable value of 38 mm yr and the overall slip rate across the east anatolian fault zone must be about 29mmyr with a range of 25

the east anatolian fault geometry segmentation and jog characteristics a detailed account is given of the fault geometry and segment structure of the east anatolian fault zone as a whole based on mapping of active faults supported by available seismological and palaeoseismological data we divide the east anatolian fault into two main strands southern and northern the main southern strand is c 580 km long between karliova and antakya and connects with the dead sea fault zone and the cyprus arc via the amik triple junction the northern strand termed the surgu misis fault system is c 350 km long and connects with the kyrenia misis fault zone beneath the gulf of iskenderun we infer that slip partitioning between the main and northern strands of the east anatolian fault accommodates 2 3 and 1 3 of the slip rate of the lateral motion between the arabian and anatolian plates respectively in the celikhan adana antakya region taking account of the time elapsed from the latest events on the east anatolian fault we suggest that the pazarcik and amanos segments have the potential to produce destructive earthquakes in the near future

gps constraints on continental deformation in the africa arabia eurasia continental collision zone and implications for the dynamics of plate interactions 1 the gps derived velocity field 1988 2005 for the zone of interaction of the arabian african nubian somalian and eurasian plates indicates counterclockwise rotation of a broad area of the earth s surface including the arabian plate adjacent parts of the zagros and central iran turkey and the aegean peloponnesus relative to eurasia at rates in the range of 20 30 mm yr this relatively rapid motion occurs within the framework of the slow moving 5 mm yr relative motions eurasian nubian and somalian plates the circulatory pattern of motion increases in rate toward the hellenic trench system we develop an elastic block model to constrain present day plate motions relative euler vectors regional deformation within the interplate zone and slip rates for major faults substantial areas of continental lithosphere within the region of plate interaction show coherent motion with internal deformations below 1 2 mm yr including central and eastern anatolia turkey the southwestern aegean peloponnesus the lesser caucasus and central iran geodetic slip rates for major block bounding structures are mostly comparable to geologic rates estimated for the most recent geological period 3 5 myr we find that the convergence of arabia with eurasia is accommodated in large part by lateral transport within the interior part of the collision zone and lithospheric shortening along the caucasus and zagros mountain belts around the periphery of the collision zone in addition we find that the principal boundary between the westerly moving anatolian plate and arabia east anatolian fault is presently characterized by pure left lateral strike slip with no fault normal convergence this implies that extrusion is not presently inducing westward motion of anatolia on the basis of the observed kinematics we hypothesize that deformation in the africa arabia eurasia collision zone is driven in large part by rollback of the subducting african lithosphere beneath the hellenic and cyprus trenches aided by slab pull on the southeastern side of the subducting arabian plate along the makran subduction zone we further suggest that the separation of arabia from africa is a response to plate motions induced by active subduction

high resolution surface velocities and strain for anatolia from sentinel 1 insar and gnss data measurements of present day surface deformation are essential for the assessment of long term seismic hazard the european space agency s sentinel 1 satellites enable global high resolution observation of crustal motion from interferometric synthetic aperture radar insar we have developed automated insar processing systems that exploit the first 5 years of sentinel 1 data to measure surface motions for the 800 000 km2 anatolian region our new 3d velocity and strain rate fields illuminate deformation patterns dominated by westward motion of anatolia relative to eurasia localized strain accumulation along the north and east anatolian faults and rapid vertical signals associated with anthropogenic activities and to a lesser extent extension across the grabens of western anatolia we show that automatically processed sentinel 1 insar data can characterize details of the velocity and strain rate fields with high resolution and accuracy over large regions these results are important for assessing the relationship between strain accumulation and release in earthquakes