western hellenic subduction and cephalonia transform local earthquakes and plate transport and strain abstract focal parameters of local earthquakes in the region of the ionian islands of western greece are constrained with a temporary dense array of three component seismographs operated jointly offshore and onshore seismic deformation is documented to be confined to the east of the n20 e striking steep continental slope west of cephalonia island the right lateral cephalonia transform fault ctf inferred from large earthquakes the pre apulian continental material appears to be only deforming east of the transform fault where it is in upper plate position to the hellenic subduction east of the transform fault the transmission velocity tomography from local earthquakes compared in depth section with a previous marine reflection profile provides evidence in support of a shallow landward dipping boundary around 12 km deep under the ionian islands along which they may override the lower plate on either side of this interface local earthquakes occur with different focal mechanisms in support with its interpretation as the interplate under cephalonia island reverse faulting deforms the upper plate along nw se structures which may also be affected by left lateral bookshelf faulting small earthquakes show normal faulting along the western coast of cephalonia and its extension 20 km ssw the trace of the ctf as inferred from the occurrence of the large strike slip earthquakes another group of normal fault earthquakes locates in the lower plate from under cephalonia to zante just outboard of a possible change of interplate dip suggested from reflection seismics landward under the islands these normal fault earthquakes appear to coincide in position with that of the load imposed by the upper plate transported over them rather than occurring in an outer rise outboard the plate boundary and trench as observed in other subductions and attributed to the control by the flexural bending of the lower plate under the pull of the sinking slab interpretation has to consider several peculiar features of plate interaction in western greece with respect to a steady state model for major subduction zones in particular a fast deformation of the upper plate in front of an orogenically overthickened crust and of the southwestward push of extruding anatolia its transport which is the cause of the migration of the plate boundary rather than the roll back of a slab which has been proposed to be detached possibly a flat and ramp shape of the interplate the geometrical complexity of the shear limit across the ctf between subduction and collision and the nearby variation of the nature of the foreland crust

determining the growth rate of topographic relief using in situ produced 10be a case study in the black forest germany abstract to determine how topographic relief in mountainous regions evolves through time we present a new approach that uses in situ produced cosmogenic 10 be to quantify 1 spatially averaged denudation rates of small watersheds and 2 local denudation rates of the ridge crests bounding these basins the technique is applied to two catchments in the black forest a forested mountain range with a local relief of a few hundred meters which is typical for ranges in central europe both the acher and the gutach catchments expose predominantly carboniferous granite and only minor amounts of high grade gneiss and triassic sandstone the latter occurs on ridges defining the eastern boundaries of the catchments above a regional unconformity in the acher and northern gutach watersheds denudation rates of subcatchments derived from 10 be concentrations in stream sediment range from 52 to 87 mm ka and 59 to 91 mm ka respectively in contrast grus samples from the ridge crests bounding both watersheds yield lower denudation rates of 34 to 59 mm ka the differences in denudation rates for sample pairs from individual subcatchments and adjacent ridge crests reveals that topographic relief is growing at a mean rate of 24 12 mm ka with the exception of the flat southwestern part of the gutach catchment where catchment wide denudation rates are similar to the rate of ridge crest lowering the inferred rates of denudation and relief growth are consistent with erosion rates calculated from the known thickness of triassic to lower jurassic sediments which were once present above the regional unconformity but have been largely eroded during the exhumation of the black forest the onset of exhumation 19 ma ago is constrained by thermal modelling of apatite fission track data which suggest a cooling rate of 3 c ma combined with a geothermal gradient of 30 to 40 c km this cooling rate yields an average exhumation rate of 75 100 mm ka for the modelled apatite fission track data which is comparable to spatially averaged denudation rates derived from cosmogenic 10 be our new approach may help to determine whether tectonically active mountain ranges are in a topographic steady state in which rates of rock uplift and denudation are equal or if such a dynamic equilibrium has not yet been attained

cosmic ray labeling of erosion surfaces in situ nuclide production rates and erosion models a number of in situ cosmogenic radionuclides and stable nuclides have been measured in natural exposed rock surfaces with a view to study their in situ production and rock erosion rates 1 the in situ radionuclides can be used for a high resolution tomography of the erosional history of an exposed surface two stable nuclides 3he 21ne and five radionuclides 10be 26al 36cl 14c 39ar having half lives in the range of 300 1 5 106 yr half life are measurable in many rock types a prerequisite for the application of the in situ nuclides for the study of erosional histories of surfaces is a knowledge of their production rates under different irradiation conditions altitude latitude irradiation geometry and shielding relative nuclide production rates can be determined fairly accurately using the extensive available data on cosmic ray neutrons 2 absolute nuclide production rates cannot generally be predicted with any accuracy because of lack of data on excitation functions of nuclides unless some normalization is possible as was done in the case of several cosmic ray produced isotopes in the atmosphere 3 based on a recent natural calibration experiment in which erosion free surfaces exposed to cosmic radiation for 11 000 yrs were sampled the absolute production rates of 10be and 26al in quartz have been accurately estimated for mountain altitudes in sierra nevada 4 the absolute production rates of 10be and 26al in quartz can therefore be estimated fairly accurately for any given latitude and altitude some measurements of 14c in rocks of low erosion rate 5 similarly allow an estimate of its production rate attempts made to measure the in situ production rates of 3he in rocks have not yet led to a convergent production rate in view of the importance of knowing the production rates of isotopes of he ne and ar i present here theoretical estimates of their production rates based on available cross section data i discuss the information that can be extracted from the study of the in situ nuclides in rocks useful parameters characterizing the exposure history of a rock surface are 1 the effective surface exposure age and 2 the time averaged erosion rate the implications of these parameters for single and multiple nuclide studies are discussed in terms of the erosion models considered

transient landscapes at fault tips 1 fault growth produces patterns of displacement and slip rate that are highly variable in both space and time this transience is most pronounced near fault tips where along strike displacement gradients vary in time as the fault array lengthens we use a set of statistical and field observations to quantify the response of catchments and their associated fans in three large normal fault arrays to transient patterns of displacement and slip rate catchments near the fault tips show distinct scaling of channel slope with drainage area compared with catchments near the strike center this scaling becomes uniform beyond about 10 km from the fault tips and is therefore like footwall relief largely decoupled from the fault displacement profile the estimated catchment response times to a change in slip rate also vary between fault tips and strike center the response times for tip catchments are much longer than the inferred time since fault activity began indicating that they are unlikely to be in equilibrium with the current fault displacement field this disequilibrium combined with the decoupling of slope area scaling from displacement indicates that landscapes are most sensitive to fault activity near fault tips active faults characterized by along strike variation in slip rate thus provide excellent opportunities to explore the transient response of landscapes to tectonic forcing

pace of landscape evolution in the sierra nevada california revealed by cosmogenic dating of cave sediments we report 26 al 10 be based ages of sierra nevada caves that constrain detailed late pliocene and quaternary river incision his tories for five river canyons rapid incision of 0 2 mm yr from 2 7 to ca 1 5 ma slowed markedly to 0 03 mm yr thereafter likely reflecting the combined effects of a transient erosional re sponse to pliocene rock uplift and periodic mantling of riverbeds with glacially derived sediment in the late quaternary while 400 m of incision has occurred in the past 2 7 m y outpacing interfluve erosion and thereby increasing the local relief canyons as deep as 1 6 km existed prior to that time these new erosion rates strength en the case for tectonically driven late cenozoic uplift

evidence for transform faulting in the ionian sea the cephalonia island earthquake sequence of 1983 accurate locations of aftershocks of the january 17 1983 ms 7 0 main shock in the ionian islands have been determined as well as fault plane solutions for this main shock and its largest aftershock which are interpreted as a right lateral strike slip motion with a thrust component on a fault striking in about a ne sw direction

the length of pre existing fissure effects on the dilatancy behavior acoustic emission and strength characteristics of cracked sandstone under different confining pressures it is significant to study the dilatancy behavior and strength characteristic of cracked rock to ensure the stability and safety of engineering rock mass consequently the effects of the length of pre existing fissures and confining pressure on the strength characteristic of sandstone specimens were analyzed and the dilatancy and acoustic emission ae behaviors of sandstone specimens with different lengths of pre existing fissures under different confining pressures were discussed the rationality of the stress of dilatancy onset can be as the strength parameter of rock is explained from the cohesion and internal friction characteristics of rock material and its dilatancy behavior the results show that the strength parameters of sandstone specimens are negative related to the length of pre existing fissures but positive related to the confining pressure the difference between the stress of dilatancy onset and peak strength decreases with the increase of length of pre existing fissures but increases with confining pressure which is related to the internal friction characteristic of rock material under the condition of uniaxial compression or low confining pressure the obvious stress drop easily occurs after the dilatancy onset and the frequency of this phenomenon is positive related to the length of pre existing fissures however this phenomenon gradually decreases with the increase of confining pressure it correspondingly transforms to the emergence of yield platform no matter what occurrence of stress drop or yield platform all the cracked rock specimens show the special characteristics of drastic increase of volume dilatancy active ae signals and full evolution of cracks after the dilatancy onset it seems to be more insecure from the way to obtain the higher strength parameters by the frequent occurrence of cohesive particles fracture in rock and the rock material can still rely on crack friction to load in addition from the dilatancy behavior of rock material it seems that the large deformations always appear after the dilatancy onset which is more likely to cause the potential engineering danger

microseimicity and strain pattern in northwestern greece during a 7 week microearthquake experiment conducted in epirus akarnania and the ionian islands of western greece we located approximately 600 earthquakes with magnitudes between 2 and 4 2 no event was deeper than 40 km the seismicity cannot be clearly associated with any single fault except the lixourion right lateral fault located west of the ionian islands focal mechanisms of about 100 earthquakes show for a narrow band of earthquakes located along the coast ene wsw shortening consistent with the surface tectonics farther east focal mechanisms show nnw sse extension beneath the foothills of the pindus mountains which is unrelated to surface faulting but is consistent with the presently subsiding basins this strain pattern is seen far north and south of the lixourion fault and is similar to the one observed in the peloponnese it suggests that a large scale mechanism is responsible for the recent geodynamics of both the northwestern and southwestern aegean

the mw 6 3 2003 lefkada earthquake greece and induced stress transfer changes abstract a large earthquake of magnitude mw 6 3 occurred on 14 august 2003 nw of the lefkada island which is situated at the ionian sea western greece the source parameters of this event are determined using body wave modeling the focal depth was found equal to 9 km the constrained focal mechanism revealed dextral strike slip motion 15 80 and 170 the duration of the source time function was 8 s and the seismic moment 2 9 1025 dyn cm the earthquake occurred close to the northern end of the kefallinia transform fault where the 1994 moderate event and its aftershock sequence were also located the epicentral distribution of the 2003 aftershock sequence revealed the existence of two clusters the first one is located close to the epicentral area of the mainshock while the second southern close to the northwestern coast of the kefallinia island a gap of seismicity is observed between the two clusters the length of the activated zone is approximately 60 km the analysis of data revealed that the northern cluster is directly related to the mainshock while the southern one was triggered by stress transfer caused by the main event

distribution pattern of earthquake induced landslides triggered by the 12 may 2008 wenchuan earthquake abstract this paper presents the preliminary results of an extensive study of the mapping the distribution of landslides triggered by the wenchuan earthquake in sichuan province china on 12 may 2008 an extensive landslide interpretation was carried out using a large set of optical high resolution satellite images e g aster alos cartosat 1 spot 5 and ikonos as well as air photos for both the pre and post earthquake situation landslide scarps were mapped as points using multi temporal visual image interpretation taking into account shape tone texture pattern elevation and ridge and valley orientation nearly 60 000 individual landslide scarps were mapped the landslide distribution map was compared with the inventory map that was prepared directly after the earthquake which contains about 11 000 individual landslide points through the calculation of normalized landslide isopleths maps remarkable differences were observed as the earlier inventory mapping did not consider the pre earthquake situation and did not consider all individual landslides as part of the landslide inventory landslides were identified that had blocked the drainage and had formed landslide dams the landslide distribution was compared with a number of aspects such as the seismic parameters distance to epicenter distance to fault rupture co seismic fault geometry and co seismic slip distribution and geology the most remarkable correlation found was with the co seismic slip distribution and the fault geometry landslide distribution in the section of the fault that had mainly a thrust component with low angle fault plane was found to be much higher than the sections that had steeper fault angles and a major strike slip component

asperity break after 12 years the mw6 4 2015 lefkada greece earthquake the mw6 4 earthquake sequence of 2015 in western greece is analyzed using seismic data multiple point source modeling nonlinear slip patch and linear slip inversions reveal a coherent rupture image with directivity toward the southwest and several moment release episodes reflected in the complex aftershock distribution the key feature is that the 2015 earthquake ruptured a strong asperity which was left unbroken in between two large subevents of the mw6 2 lefkada doublet in 2003 this finding and the well analyzed cephalonia earthquake sequence of 2014 provide strong evidence of segmentation of the major dextral cephalonia lefkada transform fault ctf being related to extensional duplex transform zones we propose that the duplexes extend farther to the north and that the ctf runs parallel to the western coast of lefkada and cephalonia islands considerably closer to the inhabited islands than previously thought generally this study demonstrates faulting complexity across short time scales earthquake doublets and long time scales seismic gaps

determining the effect of topography on isotherms in the shallow crust using low temperature thermochronometry in tunnels apatite u th he and fission track age determinations of samples from a 20 km long near horizontal tunnel in the hochalm ankogel dome eastern tauem window austria are presented in order to determine the role of paleo topography in perturbing isotherms in the shallow crust apatite fission track ages 26 8 ma show no systematic correlation with distance along the tunnel or elevation two age components in the fission track data indicate cooling through 120 c at approximately 20 ma and 80 c at approximately 6 ma surface and tunnel u th he ages 17 9 ma and 13 5 ma respectively are consistently younger than the equivalent fission track ages u th he ages vary systematically along the tunnel with older ages at the northern and southern tunnel portals and younger ages in the central section geological factors faulting lithology appear to have had little effect on this age distribution the u th he age pattern is inconsistent with rock cooling underneath the present day hochalm ankogel dome topography the age minimum is interpreted to coincide with a paleotopographic maximum in the hochalm ankogel dome and suggests that the 40 60 c isotherms were warped sufficiently to affect apatite u th he ages the tunnel apatite u th he ages match synthetic he ages derived from a two dimensional numerical model of landscape evolution integrating the thermal model results with the data allows the relief development to be constrained and we calculate that the present day hochalm ankogel dome topography was formed at 7 to 10 ma copyright 2007 by the american geophysical union

large scale erosion rates from in situ produced cosmogenic nuclides in european river sediments abstract we have calculated long term erosion rates of 20 100 mm kyr from quartz contained 10be in the bedload of middle european rivers for catchments ranging from 102 to 105 km2 these rates average over 10 40 kyr and agree broadly with rock uplift incision and exhumation rates historic soil erosion rates and erosion rates calculated from the measured sediment loads of the same rivers moreover our new erosion rate estimates correlate well with lithology and relief however in the regen neckar loire and meuse catchments cosmogenic nuclide derived erosion rates are consistently 1 5 4 times greater than the equivalent rates derived from measured river loads this may be due to the systematic under representation of high magnitude low frequency transport events in the gauging records which cover less than a century alternatively the discrepancy may derive from spatially non uniform erosion and preferential tapping of deeper sections of the irradiation profile a third explanation relates the high cosmogenic nuclide derived erosion rates to inheritance of an elevated pleistocene erosion signal uncertainties associated with the cosmogenic nuclide derived erosion rate estimates are not greater than the potential errors in conventional estimates therefore the cosmogenic nuclide approach is an effective tool for rapid catchment wide assessment of time integrated rates of bedrock weathering and erosion and we anticipate its fruitful application to the quaternary sedimentary record

triassic evaporites and plio quaternary diapirism in western greece wide triassic evaporite outcrops run parallel to the strike of hellenide thrust faults in western greece they crop out along the leading edges of thrust sheets emplaced as part of the foreland migrating fold and thrust belt the evaporites acted as the plane of decollement for thrust sheet emplacement over much of the external hellenides plio quaternary diapirs occur locally within the broad outcrops of triassic evaporite they are the result of local mobilization of evaporite after its emplacement their rise may have been initially triggered by hellenide thrust sheet loading and subsequently accentuated by plio quaternary subsidence geophysical records and onland exposures show that diapiric rise controlled local sedimentation patterns above the sites of earlier hellenide thrusts the subsequent intrusion of diapirs into these cover sediments caused localized extensional structures to develop this is best seen in se zakinthos where strain hardened conjugate faults developed in friable pliocene sandstones early in the intrusion history principal strains calculated from these sets demonstrate patterns of extension sub orthogonal to intrusion margins they are comparable with patterns known from other field and experimental examples but contrast with some recent studies on diapir related strains

initiation and displacement of landslide induced by earthquake a study of shaking table model slope test landslide researches often focus on factor of safety critical acceleration and displacement for an earthquake induced landslide the initiation and displacement of the landslide were important factors for definition of failure in this research the shaking table model slope test is adopted for study of slope failure initiation based on analyses of limit equilibrium particle image velocimetry piv analysis and acceleration time history recorded within the model slope based on the analyses landslide initiation could be defined as surface and local movement of the slope slope failure could be defined based on the massive movement of the slope the piv analysis provides good information for identifying both surface movement and massive movement the landslide displacement determined from the slope movement provides consistent results compared to observed displacements

experimental and theoretical study of the fault slip events of rock masses around underground tunnels induced by external disturbances abstract fault slip events of rock masses around underground tunnels such as irreversible displacements and slip type rock bursts can easily occur after external disturbances to investigate the mechanism and threshold conditions of fault slip events triggered by external disturbances a series of slip experiments using red sandstone blocks were performed with various horizontal pulling forces and vertical dynamic disturbances the experimental results show that the relative vertical displacements of the adjacent blocks were the main reasons for anomalously low friction phenomenon the initial stress state strongly affected the final residual horizontal displacements and the threshold conditions of fault slip events as the shear force ratio increased the stabilities of the rock blocks became increasingly sensitive to disturbance energies and the threshold disturbance energies for causing fault slip events decreased and when was close to 1 even a considerably small disturbance triggered a sustained slip failure based on energy analyses a theoretical model was developed and a dimensionless energy parameter i was introduced to quantifiably characterize the threshold conditions of different types of fault slip events the threshold condition for rock blocks to start slipping was that the i value should reach a threshold value while the threshold conditions of a sustained slip failure were that the i value should reach a larger threshold value and should simultaneously exceed a certain value the expression for the i value was given and can reflect the dependency relationships between the disturbance energies shear force ratios and rock parameters i e the yield strain the length to height ratio and the ratio of the elastic coefficients the experimental results and the threshold conditions derived from the theoretical model are essential when carrying out stability analyses and geohazard predictions in rock engineering

intensity estimation for the 2001 bhuj earthquake india on esi 07 scale and comparison with historical 16th june 1819 allah bund earthquake a test of esi 07 application for intraplate earthquakes abstract on 26th january 2001 an earthquake of magnitude mw 7 7 occurred near bhuj in northwestern india resulting in severe environmental effects no unequivocal primary surface rupture was observed for the earthquake but it caused widespread liquefaction and lateral spreading in the rann of kachchh and little rann after the earthquake several researchers collected field evidence of secondary surface rupture rockfall dry craters and surface manifestations of liquefaction including the formation of mud volcanoes and lateral spreads in the meizoseismal area analysis of pre and post earthquake satellite images suggests that several dry streams in the rann of kachchh began to flow due to extensive liquefaction induced by the earthquake in this present study the macroseismic intensity of the bhuj earthquake is evaluated by considering these environmental effects and applying the esi 07 intensity scale to the affected area as an outcome the epicentral intensity of the 2001 bhuj earthquake was determined to be xi according to historical records and seismic catalogs 16th june 1819 allah bund earthquake caused prominent surface rupture which was not so clear in the case of 2001 bhuj earthquake but the secondary effects were similar for both earthquakes considering the environmental effects caused by the 1819 allah bund earthquake an intensity of xi was estimated for the epicentral area for both earthquakes the esi scale yields a significant difference of one to two degrees with the traditional intensity scales the 2001 bhuj earthquake and 1819 allah bund earthquake shows similar esi 07 intensity of xi despite of different epicentral locations this implies the reliability of esi 07 scale application for different earthquakes of similar dimensions in the same geological setting this study contributes to the application of esi 07 scale for indian earthquakes especially reverse faulting events and to the future improvement of the esi scale with emphasis on its applicability to historical earthquakes on the indian subcontinent also this study may help in future land use planning in the meizoseismal area of 1919 allah bund and 2001 bhuj earthquakes

low temperature thermochronology of the flanks of the southern upper rhine graben the upper rhine graben urg is the most perceptible part of the european cenozoic rift system uplifted variscan basement of the black forest and the vosges forms the flanks of the southern part of the graben apatite and zircon fission track ft analyses indicate a complex low temperature thermal history of the basement that was deciphered by inverse modelling of ft parameters the models were tested against the observed data and independent geological constraints the zircon ft ages of 28 outcrop samples taken along an e w trending transect across the black forest and the vosges range from 136 to 312 ma the apatite ft ages from 20 to 83 ma the frequency distributions of confined track lengths are broad and often bimodal in shape indicating a complex thermal history cooling below 120 c in the early cretaceous to palaeogene was followed by a discrete heating episode during the late eocene and subsequent cooling to surface temperature the modelled time temperature t t paths point to a total denudation of the flanks of urg in the range of 1 0 1 7 km for a paleogeothermal gradient of 60 c km and 1 3 2 2 km for a paleogeothermal gradient of 45 c km since the late eocene

qualitative and quantitative analysis on landslide influential factors during wenchuan earthquake a case study in wenchuan county abstract the 2008 wenchuan earthquake with a surface wave magnitude of 8 0 triggered numerous landslides along the longmenshan thrust fault belt in sichuan province of china the authors investigated various influential factors on the slope stability of 119 landslides in wenchuan county such as the horizontal peak ground acceleration slope angle slope height rock type and geological structure we separately developed acceleration attenuation laws for both the hanging wall and footwall side from 183 seismic stations these formulae confirmed the hanging foot wall effect had notable influence on landslide distribution density and occurrence probability further we explored the qualitative tendency of landslide distribution and occurrence probability related with each influential factor the results from the quantitative analysis by a multivariable method demonstrated that slope height horizontal peak ground acceleration and geological structure had a stronger effect on the sliding area and volume than slope angle and rock type

slip distribution of the 2015 lefkada earthquake and its implications for fault segmentation this work was partially supported by the uk natural environmental research council nerc through ne k011006 1 ne p008828 1 and the centre for the observation and modelling of earthquakes volcanoes and tectonics comet ga 13 m 031 http comet nerc ac uk

estimates of the rate of regolith production using and from an alpine hillslope abstract the production of regolith is a fundamental geomorphic process because most surface processes transport only unconsolidated material we use concentrations of the cosmogenic radionuclides crns 10 be and 26 al in regolith and bedrock to deduce the rate of production of regolith on an alpine hillslope in the wind river range wy these calculations are based on a theoretical model which we develop here this model shows that it is important to consider dissolution of regolith in regolith production and in basin averaged erosion rate studies rates of production of regolith are uniform along the hillslope and the mean rates for the entire hillslope deduced from 10 be and 26 al are 14 3 4 0 and 13 0 4 0 m ma 1 respectively rates of production of regolith deduced from 10 be concentrations in regolith mantled bedrock support the rates deduced from regolith concentrations in the alpine environment examined here the rate of production of regolith beneath 90 cm of regolith is nearly twice as fast as the average rate of production of regolith on bare rock surfaces which small et al small e e anderson r s repka j l finkel r 1997 erosion rates of alpine bedrock summit surfaces deduced from in situ 10 be and 26 al earth and planetary science letters 150 413 425 previously documented rock mantled with regolith probably weathers more rapidly than bare rock because the water required for frost weathering is limited on bare rock surfaces because the hillslope examined here is convex with constant curvature and regolith production and thickness are uniform down the slope the regolith volume flux must be proportional to the local slope of the hillside therefore our results are consistent with gilbert s gilbert g k 1909 the convexity of hilltops journal of geology 17 344 350 steady state hillslope hypothesis if tor height and the difference between rates of weathering on bare and regolith mantled rock provide a fair estimate of the age of summit flats steady state hillslope conditions have been attained in less than several million years

thermochronology of lower cretaceous source rocks in the idaho wyoming thrust belt lower cretaceous organic rich source rocks that are thermally mature to postmature crop out on the absaroka darby and prospect plates in linear belts that run parallel to the trace of the thrusts in the idaho wyoming portion of the idaho wyoming utah thrust belt although the common assumption is that burial by thrust plates and the synorogenic sediments derived from them have been responsible for thermal maturation of the organic rich strata commercial amounts of hydrocarbons have not been found in structural traps in this portion of the thrust belt in a companion paper burtner and nigrini demonstrated that gravity driven fluid flow in the idaho wyoming portion of the thrust belt was responsible for moving large amounts of heat from the depths of the early cretaceous foreland basin eastward toward the stable platform in this paper we demonstrate through the application of organic maturation indicators and a new refinement of the apatite fission track technique that this process heated lower cretaceous organic rich source rocks to temperatures sufficient to generate hydrocarbons hydrocarbon generation and migration occurred prior to the development of the thrusts that are often assumed to have played a major role in the generation and entrapment of hydrocarbons in this portion of the thrust belt

seismic structure and the active hellenic subduction in the ionian islands in the region of the ionian islands of western greece the active margin of the hellenic domain passes from oceanic subduction in the south to continental collision in the north linked by the right lateral cephalonia transform fault a slightly landward dipping interface revealed at 13 km depth by a single previous line in the channel between cephalonia and zante has been suggested as the interplate subduction boundary new marine multichannel reflection profiles and obs refraction and wide angle reflection data confirm the reflector as a regional feature these data evidence its extension to the south where large low angle thrust earthquakes occur offshore to zante the new profiles establish a coincidence between the focal depths of these large subduction events and the imaged bright reflective level confirming its tentative interpretation as the interplate boundary which generally appears with a positive reflection polarity in this context the ionian islands outcrop corresponds to a shallowing of the interplate boudary from south to north in the south offshore zante the interplate boundary comprises a stratified zone that may be considered as the sedimentary cover of the ionian basin oceanic like crust which forms the lower plate here the shallower position and single cycle reflection character of the interplate further north suggest that the lower plate could there be the apulian paleomargin to that basin

dating topography of the sierra nevada california using apatite u th he ages the upward motion of rock masses relative to the earth s surface has been documented for most of the main mountain belts using thermochronological and petrological techniques more fundamental to the physical processes of mountain building however is the motion of the earth s surface itself which remains elusive here we describe a technique for estimating the age of topographic relief by mapping the low temperature thermal structure imparted by river incision using the ages of apatites determined from their uranium thorium and helium contents the technique exploits horizontal variations in temperature in the shallow crust that result from range normal river drainages because cooling beneath ancient river valleys occurs earlier than beneath intervening ridges our results from the sierra nevada california indicate that two of the modern transverse drainages the kings and the san joaquin had developed deep canyons by the late cretaceous period suggesting that the high topography of the range is 50 60 million years older than generally thought

stress drop at the kephalonia transform zone estimated from the 2014 seismic sequence abstract the kephalonia transform zone ktz is a seismically active dextral transform fault decoupling the extensional deformed area of the ionian abyssal plain and the compressional deformed area of the mediterranean ridge we estimate a prominent steady state strain rate of 225 20 nstrain year across the ktz from the mean velocities of permanent global navigation satellite system gnss stations in east italy and west greece which confirms previous estimates based on the regional statistical seismicity and using the local gutenberg richter relation we investigate the energetic balance between stress accumulated as a consequence of the continuous dextral shear deformation and the average stress released by shallow seismicity if the maximum expected magnitude is mw 7 4 the estimated a and b parameters of the local gutenberg richter relation and the geodetically determined shear strain rate set an upper limit to the regional stress drop 0 4 mpa we verify these values by analyzing a seismic sequence on the ktz between january and february 2014 which culminated in the mw 6 09 event of jan 26 and the mw 6 14 event of feb 3 the estimated epicenters lie within a few kilometers from each other on the western side of the kephalonia island at a hypocentral depth 10 km the measured coseismic displacements of gnss stations in this area fit the expected surface dislocation which can be predicted for an elastic half space using the measured fault plane solutions as input if the hypocenters of the aftershocks are taken as indicator of optimal dextral shear stress orientation then a low regional deviatoric stress of 0 4 mpa that is comparable with the maximum regional stress drop estimated above is required for the coulomb stress to match the pattern of the aftershocks of the 2014 sequence as a consequence we conclude that the regional deviatoric stress and the seismically released shear stress are in close balance in the ktz seismic province

field observations of geological effects triggered by the january february 2014 cephalonia ionian sea greece earthquakes abstract on jan 26 and feb 3 2014 cephalonia island ionian sea greece was struck by two strong shallow earthquakes noa local magnitudes ml5 8 and ml5 7 respectively the earthquakes ruptured two sub parallel strike slip faults with right lateral kinematics during both earthquakes ground shaking phenomena such as liquefaction road failures rock falls small medium size landslides and stonewall failures were widespread all over the western part of the island no primary fault surface ruptures were observed however one patch of the rupture of the second event may have nearly reached the surface because of the abundance of surface cracks with cm size offsets mapped in the field in north paliki peninsula liquefaction phenomena were mainly triggered in reclaimed lands in the waterfront areas of argostoli and lixouri inducing structural damages to quays sidewalks and piers we also present evidence for liquefaction induced ground disruption in the recently constructed marina of argostoli which is situated at the opposite eastern shore to the town

evaluation of the macroseismic intensities triggered by the january february 2014 cephalonia greece earthquakes based on esi 07 scale and their comparison to 1867 historical event abstract on january 26th and february 3rd 2014 two earthquakes occurred onshore the island of cephalonia inducing severe environmental effects the main types of earthquake induced failures were liquefaction and slope failures and were mainly widespread at the western and central part of the island at paliki peninsula although the fact that the generated strong motions by the second event were the highest ever recorded in greece medium severity structural damages were induced few days after the occurrence of the events two post earthquake field surveys took place in order to document the generated environmental effects by taking into account these field observations it was decided to evaluate the macroseismic intensity of the february 3rd 2014 earthquake by applying the esi 07 scale as an outcome the epicentral intensity of feb 3rd 2014 was evaluated as vii esi 07 by taking into account the total affected area furthermore as it is pointed out in primary contemporary sources and seismic catalogues similar environmental failures such as liquefaction phenomena at coastal areas and large scale rockfalls were triggered by historical earthquakes at the island of cephalonia the most accurately described effects are the ones triggered by the 1867 earthquake therefore it was decided to assess the macroseismic intensities of this historical event based on the esi 07 scale and compare it with the relevant ones of feb 3rd 2014 event as an outcome it is concluded that similar intensities were assessed for both events viii esi 07 for 1867 event and vii esi 07 for the february 2014 one despite the fact that the relevant earthquake magnitudes strongly differ outlining the results of this study it is reconfirmed the importance of the recording and documentation of earthquake environmental effects in order to maintain the consistency with the historical earthquake catalogues moreover a re evaluation of historical earthquake magnitudes at the area of cephalonia island could be realized in order to accurately update the seismic hazard

methods for assessing the stability of slopes during earthquakes a retrospective abstract during the twentieth century several methods to assess the stability of slopes during earthquakes were developed pseudostatic analysis was the earliest method it involved simply adding a permanent body force representing the earthquake shaking to a static limit equilibrium analysis stress deformation analysis a later development involved much more complex modeling of slopes using a mesh in which the internal stresses and strains within elements are computed based on the applied external loads including gravity and seismic loads stress deformation analysis provided the most realistic model of slope behavior but it is very complex and requires a high density of high quality soil property data as well as an accurate model of soil behavior in 1965 newmark developed a method that effectively bridges the gap between these two types of analysis his sliding block model is easy to apply and provides a useful index of co seismic slope performance subsequent modifications to sliding block analysis have made it applicable to a wider range of landslide types sliding block analysis provides perhaps the greatest utility of all the types of analysis it is far easier to apply than stress deformation analysis and it yields much more useful information than does pseudostatic analysis

footwall topographic development during continental extension 1 we examine the progressive development of footwall topography associated with a set of active normal faults in the northeastern basin and range province of the western united states fault length and displacement increase monotonically from northeast to southwest in the study area allowing us to track both variations in footwall morphology with increasing displacement and along strike changes in morphology on a single fault we show that patterns of catchment area footwall relief and catchment outlet spacing vary predictably and are related to the growth of the range bounding normal fault array in this semiarid region full parsing of footwall drainage area and removal of antecedent topography do not occur until fault arrays grow beyond two crustal scale segments multiple segment faults with lengths of up to 150 km have footwall relief that is limited to 1000 m in the center of the footwall and that decays to zero at the fault tips over a length scale of 15 km we hypothesize that this relatively uniform footwall relief is erosionally limited and reflects the efficacy of surface processes in removing footwall material in the center of the footwall if the fault array grows by relatively steady propagation of the tips we suggest that the 15 km length scale required to reach uniform relief is related to a timescale of relief generation by the fault tip propagation rate while such propagation rates are poorly known an average rate of 10 mm yr 1 would imply footwall relief generation over a timescale of 1 myr

evaluation of factors controlling earthquake induced landslides caused by chi chi earthquake and comparison with the northridge and loma prieta events over 10 000 landslides were triggered by the september 21 1999 chi chi earthquake a large number of these landslides have been mapped from spot images and a smaller number were described in a detailed field investigation geographic information systems gis was used to conduct a spatial characterization of the slope failures including distribution of type size slope angle bedrock geology ground motion and distance from earthquake source the most abundant landslides were shallow disaggregated rock and soil slides landslides occurred primarily in tertiary sedimentary rocks which are well known for their susceptibility to landsliding in many parts of the world landslide concentration values diminish beyond epicentral distances of 40 and 70 km from the epicenter and the surface projection of the fault plane respectively ground motion was found to be the most significant factor in triggering the shallow landslides in the chi chi earthquake overall 74 of all slope failures occurred in regions with vertical ground motions greater than 0 2g and 81 of all slope failures occurred in the region with mean horizontal peak ground accelerations pga greater than 0 15g these factors were used to compare landslides generated by the chi chi earthquake to the landslides triggered by the 1989 loma prieta earthquake and the 1994 northridge earthquake the major difference in distribution of landslides between the chi chi earthquake and the two california earthquakes was the distribution of slope angles in the chi chi earthquake 90 of the failures occurred on slopes steeper than 45 while more than 80 of failures occurred on slopes less than 50 in california apparently reflecting much steeper and tectonically more active geologic setting in taiwan

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

mapping an earthquake induced landslide based on uav imagery case study of the 2015 okeanos landslide lefkada greece abstract on november 17 2015 07 10 utc an earthquake of mw 6 5 induced slope failures mainly at the western part of the island of lefkada ionian sea greece the most characteristic one is the okeanos site deep seated landslide near village athani that affected the man made environment part of the site including a dirt road moved downwards along the coastal cliff and a luxury hotel suffered heavy damage the goal of this study is to map in detail the okeanos landslide and to provide relevant quantitative data i e structural data and volume of both the accumulated and removed material in order to achieve this a comparison between pre earthquake and post earthquake point clouds generated from aerial imagery and uav acquired photos took place using structure from motion the steep coastal cliff site was surveyed in detail even in areas that are difficult to approach results from this study show that the total landslide area covers a surface of 36 000 m2 while a removed volume of 93 000 m3 of landslide material was evaluated using change detection techniques in addition fieldwork and survey data revealed that the sliding surface was a pre existing fault surface upon which the geological material moved downwards the coastal cliff the sliding surface dips west and is exposed along a 115 m long and 25 30 m high section scarp as a conclusion this study underlines the importance of a thorough geological study in order to identify landslide prone areas prior to any building activity and shows that a uav survey is capable to provide adequate information during a post earthquake field survey for co seismic landslide mapping and modeling

bridging onshore and offshore present day kinematics of central and eastern mediterranean implications for crustal dynamics and mantle flow we present a new kinematic and strain model of an area encompassing the calabrian and hellenic subduction zones western anatolia and the balkans using haines and holt s 1993 method we derive continuous velocity and strain rate fields by interpolating geodetic velocities including recent gps data in the balkans relative motion between stable eurasia and the western aegean sea is gradually accommodated by distributed n s extension from southern balkans to the eastern corinth gulf so that the westward propagation of the north anatolian fault naf throughout continental greece or peloponnesus is not required we thus propose that the naf terminates in north aegean and that n s extension localized in the corinth gulf and distributed in southern balkans is due to the retreat of the hellenic slab the motion of the hyblean plateau apulia peninsula south adriatic sea ionian basin and sirte plain can be minimized by a single rigid rotation around a pole located in the sirte plain compatible with the opening the pelagian rifts 2 2 5 mm yr and seismotectonics in libya we interpret the trenchward ultraslow motion of the calabrian arc 2 2 5 mm yr as pure collapse the calabrian subduction being now inactive in the absolute plate motion reference frame our modeled velocity field depicts two toroidal crustal patterns located at both ends of the hellenic subduction zone clockwise in nw greece and counter clockwise in western anatolia we suggest the nw greece toroidal pattern is the surface expression of a slab tear and consequent toroidal asthenospheric flow

holocene sediment budgets in two river catchments in the southern upper rhine valley germany abstract the holocene sediments of two catchments in the southern upper rhine valley have been quantified as part of the german lucifs programme rheinlucifs which aims to quantify sediment fluxes in the rhine catchment since the onset of agriculture in the neolithic about 7500 years ago the spatial distribution of the alluvial and colluvial sediments was derived using geological maps with information on the thickness of these sediments from various sources including auger profiles and data from excavations the sediments were subdivided into characteristic sedimentary storage types according to the different types of landscapes for each of the sedimentary storage types an average thickness was assessed so that an integral sediment balance for the holocene could be derived for the different types of landscapes in the study area 32 holocene sedimentary storage types were determined 21 in the elz catchment 1500 km 2 and 11 in the mohlin catchment 230 km 2 by adding up the sediment volumes of all single sedimentary storage types the total holocene sediment volumes for the two catchments were calculated erosion depths were determined by dividing the sediment volumes through the potential erosion areas slope 2 and by assuming a sediment delivery ratio sdr between 0 and 0 4 the total erosion for the potential erosion areas during the holocene was calculated as 31 61 cm in the elz catchment and 44 79 cm in the mohlin catchment

seismically induced mass movements and volumetric fluxes resulting from the 2010 mw 7 2 earthquake in the sierra cucapah mexico the observation that sediment flux from mountain ranges struck by high magnitude earthquakes can be strongly influenced by coseismic mass movements brings into question the nature of coseismic deformation as a net contributor to mountain building to better constrain the role of high magnitude earthquakes in orogenesis high resolution data of earthquake induced mass wasting is required for areas of differing tectonic morphological and climatic settings here we compare the erosional flux to the tectonic flux associated with the 2010 mw 7 2 sierra el mayor earthquake in mexico and examine the landslide patterning of coseismic mass movements associated with this event the ruptured fault system has a significant strike slip component with subsidence along the eastern flank and uplift on the western flank of the range peak ground acceleration was highest along the steepest sections of the range such that the frequency of landslide occurrence was strongly correlated to slope gradient both vertical and horizontal coseismic displacement demonstrated a strong control over landslide initiation this result suggests that strike slip systems experience very different landslide patterning to thrust faults during earthquakes based on interferometric analysis of synthetic aperture radar images the earthquake resulted in a total uplifted volume of 41 6 106 m3 and a loss of 95 2 106 m3 due to subsidence this suggests a net tectonic volumetric flux of 53 6 106 m3 sediment mobilisation by coseismic landslides is estimated at 2 7 106 m3 derived from a manually mapped inventory using spot 5 multispectral imagery thus the net volume loss through coseismic subsidence of the mountain range generated a strongly negative mass flux which was only marginally enhanced by mass wasting

bedrock incision rock uplift and threshold hillslopes in the northwestern himalayas the topography of tectonically active mountain ranges reflects a poorly understood competition between bedrock uplift and erosion dating of abandoned river cut surfaces in the northwestern himalayas reveals that the indus river incises through the bedrock at extremely high rates 2 12 mm yr 1 in the surrounding mountains the average angles of hillslopes are steep and essentially independent of erosion rate suggesting control by a common threshold process in this rapidly deforming region an equilibrium is maintained between bedrock uplift and river incision with landsliding allowing hillslopes to adjust efficiently to rapid river down cutting

properties of the 2003 lefkada ionian islands greece earthquake seismic sequence and seismicity triggering on 14 august 2003 lefkada island central ionian was strongly af fected by an mw 6 2 earthquake a dense temporary seismic network was installed one day after and accurately located hundreds of aftershocks that defined in detail the main rupture as well as the activity distribution in the neighboring fault segments the main rupture occupied the northwestern part of the coastline and trends north northeast south southwest in agreement with regional tectonics regional network locations were appropriately calibrated using the local network data allowing the relocation of the mainshock and strong m 4 5 or larger aftershocks during the first day intense aftershock activity took place up to 40 km beyond the southern end of the main rupture theoretical static stress changes from the mainshock give a preliminary explanation for the aftershock distribution aside from the main rupture as well as triggering of seismicity in the nearby kefalonia fault providing evidence for future seismic hazard ensuing from this fault

using in situ produced cosmogenic isotopes to estimate rates of landscape evolution a review from the geomorphic perspective the application of in situ produced cosmogenic isotopes to problems in geomorphology has increased rapidly over the past decade at least 57 papers and numerous abstracts have been published since the mid 1980s when the first mass spectrometric measurements of terrestrially produced cosmogenic isotopes were made taken at face value these studies provide quantitative information about rates of landscape evolution and landform age however the significance of calculated erosion rates and exposure ages depends strongly on the models used to interpret isotopic data the validity of assumptions inherent to these models and the geologic surroundings in which the samples were collected this paper attempts to place cosmogenic isotope studies in a geomorphic context by reviewing fundamentals of the method and evaluating the validity of assumptions under which these data have been interpreted at present the establishment of high precision cosmogenically based glacial and alluvial chronologies is stymied by the evolution of geomorphic surfaces the erosion of rock from sampled boulders the potential for isotope inheritance from previous exposure and the uncertainty of isotopic measurements uncertainties in isotope production rates and the observed variability of exposure ages on individual geomorphic surfaces limit the confidence with which cosmogenic ages can be correlated reliably with those obtained by other techniques estimation of erosion rates at single points on the landscape gives useful small scale information extrapolation of these rates over longer time and larger spatial scales is less sure and most likely biased toward lower erosion rates by die inadvertent selection of resistant sample sites however because erosion rates are so poorly constrained at present even estimates to within a factor of 2 may be of significant value to geomorphologists and tectonicists

plio pleistocene transpressional reactivation of paleozoic and paleogene structures in the rhine bresse transform zone northern switzerland and eastern france pliocene to recent uplift and shortening in the southern rhinegraben is documented by deformation of pliocene fluvial gravels deposited on a nearly planar surface as well as by progressive deflection and capture of rivers this deformation is suggested to result from thick skinned tectonic movements as evidenced by ob servations on seismic records which demonstrate a spatial coincidence between en chelon anticlines at the surface and faults located in the crystalline basement these findings contradict the often invoked thin skinned tectonism in the recent tectonic history of the rhine graben in particular the transfer zone between the rhinegraben and the bressegraben is very suitable for reactivation under the present day stress field thick skinned reactivation of faults in the basement is also expressed by focal plane mechanisms of recent earth quakes showing strike slip rather than reverse faulting characteristics this is of importance for the densely populated and industrialised southern rhinegraben pre viously affected by large earthquakes in historical times e g basel 1356

the 1953 earthquake in cephalonia western hellenic arc coastal uplift and halotectonic faulting summary geomorphological marine biological and radiometric data in combination with earlier reports reveal that the m 7 2 1953 cephalonia earthquake the most destructive but least studied earthquake in greece this century was associated with a 0 3 0 7m quasi rigid body uplift and westward tilting of the central part of the island another palaeoseismic event around 1500 yr bp associated with coastal uplifts was also identified structural data indicate that the 1953 uplift is bounded by two subparallel east dipping major reverse faults and corresponds to a piston like motion this structurally unusual pattern of seismic deformation is detached from the deformation of the basement conspicuously a thrust and different from the long term deformation pattern of the area it is probably due to the particularities of salt tectonics a 1500m thick salt layer acts as a regional dccollement while thinner layers are sandwiched between the carbonate thrust sheets that compose the overburden and reduce their friction during fault movement this crustal anisotropy is responsible for the observed anomalous attenuation of seismic waves during the 1953 and historical earthquakes the 1953 seismic surface deformation mimics long term halotectonic patterns but is not directly indicative of the regional stress field for it reflects uplift induced stresses only

abrupt glacial valley incision at 0 8 ma dated from cave deposits in switzerland glacial erosion dramatically alters mountain landscapes but the pace at which glaciers carve a previously fluvial landscape remains poorly defined because long term valley incision rates are difficult to measure here we reconstruct the lowering history of the aare valley switzerland over the past 4 m y by dating cave sediments with cosmogenic 26al and 10be incision accelerated from 120 m m y to 1200 m m y at 0 8 1 0 ma at least 1 m y after the onset of local glaciation rapid incision may have been triggered by lowering of the equilibrium line altitude at the mid pleistocene climate transition

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

spatial distribution of landslides triggered from the 2007 niigata chuetsu oki japan earthquake abstract understanding the spatial distribution of earthquake induced landslides from specific earthquakes provides an opportunity to recognize what to expect from future events the july 16 2007 mw 6 6 mjma 6 8 niigata chuetsu oki japan earthquake triggered hundreds of landslides in the area surrounding the coastal city of kashiwazaki and provides one such opportunity to evaluate the impacts of an offshore magnitude 6 earthquake on a steep coastal region as part of a larger effort to document all forms of geotechnical damage from this earthquake we performed landslide inventory mapping throughout the epicentral area and analyzed the resulting data for spatial seismic motion and geologic correlations to describe the pattern of landsliding coupled with examination of a third party aerial photo based landslide inventory our analyses reveal several areas of high landslide concentration that are not readily explained by either traditional epicentral and fault plane distance metrics or by recorded and inferred ground motions whereas average landslide concentrations averaged less than 1 landslide per square kilometer ls km2 some areas reached up to 2 ls km2 in the nishiyama hills to the northeast of kashiwazaki and between 2 and 11 ls km2 in coastal areas to the north and south of the city correlation with seismometer based and monument overturning back calculated ground motions suggests that a minimum peak ground acceleration pga of approximately 0 2 g was necessary for landsliding throughout the region but does not explain the subregional areas of high landslide concentration however analysis of topographic slope and the distribution of generally weak dip slope geologic units does sufficiently explain why on a sub regional scale high landslide concentrations occurred where they did these include 1 an inland region of steep dip slope anticlinal sedimentary strata with associated fold belt compression and uplift of the anticline and 2 coastal areas with generally weaker weathered outcrop lithology and steeper slopes resulting from active marine and terrestrial cliff processes the results offer lessons for understanding the effects of earthquakes on both regional and subregional scales with regard to the spatial distribution of landsliding

relation between rock uplift and denudation from cosmogenic nuclides in river sediment in the central alps of switzerland 1 a north south traverse through the swiss central alps reveals that denudation rates correlate with recent rock uplift rates in both magnitude and spatial distribution this result emerges from a study of in situ produced cosmogenic 10be in riverborne quartz in central alpine catchments as a prerequisite we took care to investigate the potential influence of shielding from cosmic rays due to snow glaciers and topographic obstructions to calculate a possible memory from last glacial maximum lgm glaciation and to identify a watershed size that is appropriate for systematic sampling mean denudation rates are 0 27 0 14 mm a for the alpine foreland and 0 9 0 3 mm a for the crystalline central alps the measured cosmogenic nuclide derived denudation rates are in good agreement with post lgm lake infill rates and are about twice as high as denudation rates from apatite fission track ages that record denudation from 9 to 5 ma in general denudation rates are high in areas of high topography and high crustal thickness the similarity in the spatial distribution and magnitude of denudation rates and those of rock uplift rates can be interpreted in several ways 1 postglacial rebound or climate change has introduced a transient change in which both uplift and denudation follow each other with a short lag time 2 the amplitude of glacial to interglacial changes in both is small and is contained in the scatter of the data 3 both are driven by ongoing convergence where their similarity might hint at some form of long term quasi steady state or 4 enhanced continuous quaternary erosion and isostatic compensation of the mass removed accounts for the distribution of present day rock uplift

erosion rates on different timescales derived from cosmogenic 10 be and river loads implications for landscape evolution in the rhenish massif germany we determined erosion rates on timescales of 101 104 years for two catchments in the northeastern rhenish massif in order to unravel the quaternary landscape evolution in a variscan mountain range typical of central europe spatially averaged erosion rates derived from in situ produced 10be concentrations in stream sediment of the aabach and mohne watersheds range from 47 6 to 65 14 mm ka and integrate over the last 9 13 ka these erosion rates are similar to local rates of river incision and rock uplift in the quaternary and to average denudation rates since the mesozoic derived from fission track data this suggests that rock uplift is balanced by denudation i e the landscape is in a steady state short term erosion rates were derived from suspended and dissolved river loads subsequent to 1 correcting for atmospheric and anthropogenic inputs 2 establishing calibration curves that relate the amount of suspended load to discharge and 3 estimating the amount of bedload the resulting solid mass fluxes suspended and bedload agree with those derived from the sediment volume trapped in three reservoirs however resulting geogenic short term erosion rates range from 9 to 25 mm ka and are only about one third of the rates derived from 10be model simulations in combination with published sediment yield data suggest that this discrepancy is caused by at least three factors 1 phases with higher precipitation and or lower evapotranspiration 2 rare flood events not captured in the short term records and 3 prolonged periods of climatic deterioration with increased erosion and sediment transport on hillslopes

dynamic equilibrium among erosion river incision and coastal uplift in the northern and central apennines italy erosion river incision and uplift rates in the northern and central apennines italy since 0 9 ma are determined from new cosmogenic nuclide data beryllium 10 concentrations in modern and middle pleistocene sediments indicate erosion rates from 0 20 to 0 58 mm yr these rates are similar to estimates of sediment yield 0 12 0 44 mm yr river incision 0 35 mm yr and uplift 0 01 1 0 mm yr rates inferred from other methods that integrate landscape process rates since the early pleistocene these rates of landscape change are significantly lower than long term exhumation rates of 1 2 mm yr since ca 4 5 ma inferred from thermochronometry collectively these data suggest that hillslope erosion and river incision rates in the northern and central apennines have balanced local uplift rates for 1 my but that exhumation rates have slowed significantly since emergence of the mountain chain in the pliocene this condition of dynamic equilibrium was potentially achieved within ca 3 ma similar to some model predictions of hillslope and fluvial system adjustment

paleoelevation reconstruction using pedogenic carbonates paleoelevation reconstruction using stable isotopes although a relatively new science is making a significant contribution to our understanding of the recent growth of the world s major orogens in this review we examine the use of both light stable isotopes of oxygen and the new clumped isotope 47 carbonate thermometer in carbonates from soils globally the oxygen isotopic composition 18 o of rainfall decreases on average by about 2 8 km of elevation gain this effect of elevation will in turn be archived in the 18 o value of soil carbonates and paleoelevation can be reconstructed provided 1 temperature of formation can be estimated 2 the effects of evaporation are small 3 the effects of climate change can be accounted for and 4 the isotopic composition of the carbonate is not diagenetically altered we review data from modern soils to evaluate some of these issues and find that evaporation commonly elevates 18 o values of carbonates in deserts an effect that would lead to underestimates of paleoelevation some assessment of paleoaridity using qualitative indicators or carbon isotopes from soil carbonate is therefore useful in evaluating the oxygen isotope based estimates of paleoelevation sampling from deep 50 cm in paleosols helps reduce the uncertainties arising from seasonal temperature fluctuations and from evaporation the new clumped isotope 47 carbonate thermometer expressed as 47 offers an independent and potentially very powerful approach to paleoelevation reconstruction in contrast to the use of 18 o values nothing need be known about the isotopic composition of water from which carbonate grew in order to estimate of temperature of carbonate formation from 47 values using assumed temperature lapse rates with elevation paleoelevations can thereby be reconstructed case studies from the andes and tibet show how these methods can be used alone or in combination to estimate paleoelevation in both cases the potential for diagenetic alteration of primary carbonate values first has to be assessed clear examples of both preservation and alteration of primary isotopic values are available from deposits of varying ages and burial histories 47 values constitute a relatively straightforward test since any temperature in excess of reasonable surface temperatures points to diagenetic alteration for 18 o values preservation of isotopic heterogeneity between different carbonate phases offers a check on diagenesis results of these case studies show that one area of south central tibet attained elevations comparable to today by the late oligocene whereas 2 7 0 4 km of uplift occurred in the bolivian altiplano during the late miocene

fault model for the 2015 leucas aegean arc earthquake analysis based on seismological and geodetic observations the 17 november 2015 m w 6 6 earthquake in leucas leukas lefkas or lefkada island in the ionian sea western aegean arc was modeled using teleseismic long period p and sh waveforms and global positioning system gps slip vectors detailed fault modeling in this region characterized by intense seismicity and deformation rates usually assigned to the cephalonia transform fault is a challenge because of the unfavorable observation system to overcome this problem we independently analyzed seismological and geodetic data and then jointly evaluated the results the adopted model indicates that the 2015 earthquake can be assigned to a shallow strike slip fault with a minor component of thrusting along the southwest coasts of leucas and with relatively high slip for the area additionally mostly low angle fault solutions satisfying geodetic observations were identified but were not further investigated the preferred fault model permits recognition that recent m w 6 0 earthquakes in the area some marked by extreme peak ground accelerations are associated with a string of strike slip or oblique slip occasionally overlapping fault segments with variable characteristics along or close to the west coasts of leucas and cephalonia keffalinia kefalonia islands whereas the catastrophic 1953 m w 7 2 cephalonia and other previous major earthquakes were associated with thrust faulting electronic supplement 1 table of the global positioning system gps derived displacements and figures of p wave first motion polarities comparison of earthquake source parameters gps time series 2d projections of geodetic solutions the variance covariance matrix of the geodetic solution and the geodetic variable slip model 1 http www bssaonline org lookup suppl doi 10 1785 0120160080 dc1

late cretaceous reactivation of major crustal shear zones in northern namibia constraints from apatite fission track analysis abstract namibia s passive continental margin records a long history of tectonic activity since the proterozoic the orogenic belt produced during the collision of the congo and kalahari cratons in the early proterozoic led to a zone of crustal weakness which became the preferred location for tectonism during the phanerozoic the pan african damara mobile belt forms this intraplate boundary in namibia and its tectonostratigraphic zones are defined by ductile shear zones where the most prominent is described as the omaruru lineament waterberg thrust oml wt the prominance of the continental margin escarpment is diminished in the area of the central and northern zone of the damara belt where the shear zones are located this area has been targeted with a set of 66 outcrop samples over a 550 km long 60 km broad coast parallel transect from the top of the escarpment in the south across the damara sector to the kamanjab inlier in the north apatite fission track age and length data from all samples reveal a regionally consistent cooling event thermal histories derived by forward modelling bracket this phase of accelerated cooling in the late cretaceous maximum palaeotemperatures immediately prior to the onset of cooling range from ca 120 to ca 60 c with the maximum occurring directly south of the omaruru lineament because different palaeotemperatures indicate different burial depth at a given time the amount of denudation can be estimated and used to constrain vertical displacements of the continental crust we interpret this cooling pattern as the geomorphic response to reactivation of basement structures caused by a change in spreading geometry in the south atlantic and south west indian oceans

landslide inventories the essential part of seismic landslide hazard analyses abstract a detailed and accurate landslide inventory is an essential part of seismic landslide hazard analysis an ideal inventory would cover the entire area affected by an earthquake and include all of the landslides that are possible to detect down to sizes of 1 5 m in length the landslides must also be located accurately and mapped as polygons depicting their true shapes such mapped landslide distributions can then be used to perform seismic landslide hazard analysis and other quantitative analyses detailed inventory maps of landslide triggered by earthquakes began in the early 1960s with the use of aerial photography in recent years advances in technology have resulted in the accessibility of satellite imagery with sufficiently high resolution to identify and map all but the smallest of landslides triggered by a seismic event with this ability to view any area of the globe we can acquire imagery for any earthquake that triggers significant numbers of landslides however a common problem of incomplete coverage of the full distributions of landslides has emerged along with the advent of high resolution satellite imagery

slip model of the 17 november 2015 mw 6 5 lefkada earthquake from the joint inversion of geodetic and seismic data we inferred the rupture process of the 2015 lefkada earthquake by combining teleseismic and near field strong motion data together with static and dynamic gps displacements the joint inversion of all data sets revealed a relatively complex slip pattern with a heterogeneous distribution slip is confined in the upper 10 km two principal asperities with peak slip amplitude of 2 35 m which released 65 of the total seismic moment were recovered southwest of the epicenter remarkably the 2015 earthquake ruptured the part of the cephalonia transform fault zone that remained unbroken during the 2003 event revealing a pattern of rupture segmentation along the fault zone in this context the lefkada segment can be divided into a northern and southern part preseismic deformation onshore southern lefkada revealed that since the 2003 rupture the northern part of the lefkada segment continuously loaded the southern part which eventually broke during the 2015 event

engineering geological mapping of earthquake induced landslides in south lefkada island greece evaluation of the type and characteristics of the slope failures a moderate shallow depth earthquake mw 6 5 occurred onshore lefkada island on november 17 2015 with the focal depth estimated at 11 km the seismic fault is a near vertical strike slip fault running along the western coast part of the cephalonia transform fault landslides and ground cracks were mainly reported at the western part of the island inducing structural damages high severity slope failures occurred at egremnoi and gialos areas that both are located at coastal regions this study aims to investigate the engineering geological conditions at these areas and assess the characteristics and physical quantities e g type area m2 and volume m3 of the instabilities to achieve this engineering geological mapping was implemented in egremnoi and gialos area aiming to a classify the geological units mapped on the heavily damaged areas and b to correlate them with the type of slope failures furthermore type and dimensions of slope failures were evaluated to estimate the total volume of the mass movement all the data originated from the engineering geological mapping have been digitized and rasterized at 5 m grid spacing using the arc info gis software to perform a newmark s sliding block analysis the outcome arisen by this analysis is that the generated by the earthquake peak ground acceleration at these areas should be at least 0 45 g to trigger these kinds of slope failures

denudation rates determined from the accumulation of in situ produced 10be in the luquillo experimental forest puerto rico we present a simple method for estimation of long term mean denudation rates using in situ produced cosmogenic 10be in fluvial sediments procedures are discussed to account for the effects of soil bioturbation mass wasting and attenuation of cosmic rays by biomass and by local topography our analyses of 10be in quartz from bedrock outcrops soils mass wasting sites and riverine sediment from the icacos river basin in the luquillo experimental forest puerto rico are used to characterize denudation for major landform elements in that basin the 10be concentration of a discharge weighted average of size classes of river sediment corresponds to a long term average denudation of 43 m ma 1 consistent with mass balance results

advances and problems in understanding the seismic response of potentially unstable slopes abstract the influence of site effects on landslide triggering during earthquakes has been inferred in several studies but its evaluation is made difficult by the complexity of factors controlling the dynamic response of potentially unstable slopes and also by the lack of local ground motion instrumental observations this work explores this problem and reports new findings based on an ongoing long term accelerometric monitoring conducted on a landslide prone test area in the apennine mountains italy where the presence of site effects enhancing seismic susceptibility of local slopes has been invoked on the basis of historic accounts of landsliding triggered at large epicentral distance the recordings relative to low to moderate magnitude earthquakes showed significant amplifications affecting hillslope portions covered by thick 5 m colluvia and pronounced amplification maxima oriented along the local maximum slope direction on a recent deep seated landslide while the amplifications seem most likely linked to high impedance contrast between surface materials and underlying substratum the causes of directivity are less clear the case of the monitored test site together with evidence of site response directivity identified on other hillslopes suggest that the directivity phenomena can result from a combination of topographic lithological and structural factors that act together to re distribute shaking energy focusing it on site specific directions thus it is difficult to single out the critical factors controlling such phenomena and no general criterion for the identification of sites affected by directivity is proposed here nevertheless the presence and orientation of site response directivity can be revealed through reconnaissance techniques by using recordings of seismic weak motion and or ambient microtremors and calculating azimuthal variation of shaking energy and horizontal to vertical ground motion spectral ratios a comparison with the recordings obtained during the recent m w 6 3 earthquake that hit the abruzzo region in april 2009 demonstrated that analysis relying on data from low energy events can furnish valid indications for slope behaviour also under stronger shaking provided the data are well differentiated in terms of distance azimuth and source characteristics furthermore the comparative analysis of the abruzzo earthquake recordings at a landslide and reference sites showed that directivity properties of strong shaking had been correctly anticipated using earlier weak motion observations however under the complex slope conditions the identification of resonance frequencies from horizontal to vertical spectral ratios estimated from weak motion accelerometric recordings does not seem reliable and better results have been obtained by velocimetric microtremor recordings

active tectonics of the southeastern upper rhine graben freiburg area germany the upper rhine graben has two plio quaternary depocentres usually interpreted as resulting from tectonic reactivation the southern basin near freiburg im breisgau germany contains up to 250 m of sediments beneath the younger alluvial deposits related to the current drainage system a former river network deeply entrenched in the substratum reveals a very low regional base level of early pleistocene age the offset of channels at faults allows us to infer a pleistocene reactivation of the syn rift fault pattern and the estimation of slip rates maximum vertical movements along the faults have not exceeded 0 1 mm yr since the middle pleistocene current activity is concentrated along the westernmost faults morphologic markers indicate late pleistocene reactivation of the rhine river fault and geophysical prospecting suggests a near surface offset of young sedimentary deposits the size of the fault segments potentially reactivated suggests that earthquakes with magnitude larger than mw 6 3mw 6 3 could be expected in the area with a return interval of about 8000 years extrapolated to the duration of the plio pleistocene the strain rate estimates reveal that the tectonic forcing may account for only one third to one half of the whole thickness of the plio pleistocene sediments of the basin fill thus other processes must be invoked to understand the growth of the plio pleistocene basin especially the piracy of the rhine river to the north during the early pleistocene could explain these effects

spatially averaged long term erosion rates measured from in situ produced cosmogenic nuclides in alluvial sediment spatially averaged erosion rates of small catchments can be accurately inferred from the concentrations of cosmogenic nuclides in stream sediment here we test this technique at two catchments by comparing erosion rates inferred from cosmogenic nuclides with rates of alluvial fan deposition over the past 16 000 years these two independent estimates agree within one standard error demonstrating that cosmogenic nuclide signatures of stream sediment can be used to measure spatially averaged long term erosion rates using this technique we show that long term erosion rates are an exponential function of average hillslope gradient at these sites

complex rupture mechanism and topography control symmetry of mass wasting pattern 2010 haiti earthquake the 12 january 2010 mw 7 0 haiti earthquake occurred in a complex deformation zone at the boundary between the north american and caribbean plates combined geodetic geological and seismological data posited that surface deformation was driven by rupture on the leog ne blind thrust fault while part of the rupture occurred as deep lateral slip on the enriquillo plantain garden fault epgf the earthquake triggered 4490 landslides mainly shallow disrupted rock falls debris soil falls and slides and a few lateral spreads over an area of 2150 km2 the regional distribution of these slope failures defies those of most similar earthquake triggered landslide episodes reported previously most of the coseismic landslides did not proliferate in the hanging wall of the main rupture but clustered instead at the junction of the blind leog ne and epgf ruptures where topographic relief and hillslope steepness are above average also low relief areas subjected to high coseismic uplift were prone to lesser hanging wall slope instability than previous studies would suggest we argue that a combined effect of complex rupture dynamics and topography primarily control this previously rarely documented landslide pattern compared to recent thrust fault earthquakes of similar magnitudes elsewhere we conclude that lower static stress drop mean fault displacement and blind ruptures of the 2010 haiti earthquake resulted in fewer smaller and more symmetrically distributed landslides than previous studies would suggest our findings caution against overly relying on across the board models of slope stability response to seismic ground shaking

statistical analysis of an earthquake induced landslide distribution the 1989 loma prieta california event the 1989 loma prieta california earthquake moment magnitude m 6 9 generated landslides throughout an area of about 15 000 km2 in central california most of these landslides occurred in an area of about 2000 km2 in the mountainous terrain around the epicenter where they were mapped during field investigations immediately following the earthquake the distribution of these landslides is investigated statistically using regression and one way analysis of variance anova techniques to determine how the occurrence of landslides correlates with distance from the earthquake source slope steepness and rock type the landslide concentration defined as the number of landslide sources per unit area has a strong inverse correlation with distance from the earthquake source and a strong positive correlation with slope steepness the landslide concentration differs substantially among the various geologic units in the area the differences correlate to some degree with differences in lithology and degree of induration but this correlation is less clear suggesting a more complex relationship between landslide occurrence and rock properties

palaeo altimetry of the late eocene to miocene lunpola basin central tibet the elevation history of the tibetan plateau provides direct insight into the tectonic processes associated with continent continent collisions here we present oxygen isotope based estimates of the palaeo altimetry of late eocene and younger deposits of the lunpola basin in the centre of the plateau which indicate that the surface of tibet has been at an elevation of more than 4 kilometres for at least the past 35 million years we conclude that crustal but not mantle thickening models combined with plate kinematic solutions of india asia convergence are compatible with palaeo elevation estimates across the tibetan plateau

using the inqua scale for the assessment of intensity case study of the 2003 lefkada ionian islands greece earthquake abstract a new scale has been introduced by the inqua subcommission on paleoseismicity for evaluating the intensity of an earthquake by examining the earthquake environmental effects the definitions of the intensity degrees provided by the inqua scale are based solely on the ground effects such as liquefaction rockfalls and ground fissures the lefkada western greece earthquake of 2003 mw 6 2 ms 6 4 has been selected as a case study for testing the accuracy and reliability of the inqua scale the evaluated intensity parameters of the 2003 earthquake based on the mm and ems scales are compared with the one assessed using the inqua intensity scale furthermore these degrees of inqua intensity were compared with the values of intensity of past events from this comparison we conclude that in greece in urban areas developed according to the provisions of the upgraded seismic codes the evaluated intensities based on ems scale may underestimate the ground shaking in order to assess accurately the seismic hazard of an area the use of the inqua scale in combination with the ems scale is suggested

the 2003 lefkada earthquake field observations and preliminary microzonation map based on liquefaction potential index for the town of lefkada abstract a strong earthquake mw 6 2 occurred offshore the island of lefkada or lefkas on august 14 2003 the maximum intensity has been evaluated io viii ems at lefkada municipality while vi to vii intensities were evaluated at many other villages of the island the offshore nne ssw oriented strike slip right lateral fault was activated by the main shock this fault is the northern termination of the cephalonia transform fault the most characteristic macroseismic effects were extensive typical ground failures like rock falls soil liquefactions subsidence densification ground cracks and landslides these macroseismic effects are remarkably similar to those reported from some historical lefkada shocks e g 1704 1914 ms 6 3 and 1948 ms 6 5 sand boils and ground fissures with ejection of mud were observed at the seaside of the town of lefkada and in the villages of nydri and vassiliki in situ soil profiles are obtained based mainly on borings after the earthquake boreholes records with spt values standard penetration test are obtained and the simplified procedure originally developed by seed and idriss was employed to evaluate the liquefaction resistance of soils the results indicated that the silty sandy layer which lies beneath the artificial fill in the coastal zone in lefkada town had liquefied during the 14 august earthquake an attempt was also made to establish a preliminary microzonation map for lefkada town using the data from liquefaction potential index analyses our map was validated by the occurrence of liquefaction phenomena inside the town

lithology landscape dissection and glaciation controls on catchment erosion as determined by cosmogenic nuclides in river sediment the wutach gorge black forest cosmogenic nuclides measured in quartz from recent river bedload provide a novel tool to quantify catchment wide erosion rates at geologically meaningful time scales here we present an analysis of the geomorphological evolution of the 350 km2 wutach catchment in the uplands of the south west german black forest the robustness of the method is demonstrated by the fact that although the area was affected by river capture at 18 kyr bp the formed gorge is so narrow that spatially averaged erosion rates were not resolvably perturbed however because cosmogenic nuclides preserve an erosion memory of several thousand years the only perturbation introduced was detected in the minor areas that have been subject to the last maximum glaciation in unglaciated areas an important relationship between lithology and erosion can by quantified sandstone lithologies erode at 12 18 mm kyr 1 granite lithologies at 35 47 mm kyr 1 and limestone lithologies as deduced from river load gauging at 70 90 mm kyr 1

the november 17th 2015 lefkada greece strike slip earthquake field mapping of generated failures and assessment of macroseismic intensity esi 07 abstract on november 17 2015 a strong shallow earthquake mw 6 5 occurred on the island of lefkada along a n20 5 e east dipping strike slip fault with right lateral sense of slip the event triggered environmental effects that were mainly mapped at the western part of the island while moving towards the eastern part the severity of the earthquake induced failures decreased the most characteristic geological effects that were triggered by the earthquake were slope failures including rock falls rock slides and landslides the spatial density of the failures follows an exponential increase with slope angle and decreases for values larger than 55 small size liquefaction phenomena such as sand craters and ejection of fine grained sand through ground cracks were documented at the coastal area of vassiliki the epicentral intensity was assessed based on the definitions of environment seismic intensity scale as viii esi 07 and the macroseismic epicenter viii up to ix was located at the coastal area of egremnoi west of athani village south lefkada in addition comparing the severity of earthquake induced failures on the main road network triggered by the 2003 and 2015 events it is concluded that the behavior of the protection measures such as fences and walls could be generally characterized as satisfactory on the contrary the similarity of the structural failures triggered by the 2003 event with the ones triggered by the 2015 earthquake documented at the port of vassiliki indicates that the post 2003 constructed port facilities failed to guarantee the functionality of the port of vassiliki

low long term erosion rates in high energy mountain belts insights from thermo and biochronology in the eastern pyrenees abstract we relate the high elevation of flat topography in the eastern pyrenees to the resurrection of a mountain belt which prior to 12 ma was a low relief landscape or peneplain bevelling eroded stumps of the pyrenean compressional orogen new apatite fission track and u th he data together demonstrate the consistently young age

deciphering the rate of mountain growth during topographic presteady state an example from the ne margin of the tibetan plateau 1 we use field investigations topographic profiles and 10be exposure dating to constrain the growth rate of the yumu shan a thrust bounded mountain range at the northeastern margin of tibet wind gaps fault scarps at the mountain front and hanging paleocatchments indicate that the yumu shan is growing both laterally and vertically scarp profiles and 10be ages yield rock uplift rates of 500 and 800 mm ka 1 for the eastern and central parts of the range respectively the fact that the rock uplift rate in the high center of the yumu shan exceeds catchment wide 10be denudation rates which range from 180 to 280 mm ka 1 indicates that the mountain range continues to rise and has not yet reached a topographic steady state combining the total structural relief of the range with the rates of rock uplift and denudation suggests that the growth of the yumu shan started 3 7 0 9 ma ago

formation of joints in cooling plutons abstract the geometry age and mineralogy of steeply dipping joints in the lake edison granodiorite of california indicate that thermal stresses played a key role in the formation of the joints joint traces curve to approach the pluton boundary at high angles at both large and small scales and they generally terminate at or near the contact with an older pluton radiometric dates and the epidote and chlorite fillings of the joints tie jointing to the initial cooling of the pluton a thermo mechanical stress analysis assuming two dimensional conductive cooling predicts thermal stresses of several tens of mpa the same order of magnitude as plausible fluid pressures regional stresses and lateral normal stresses associated with the overburden the orientation of the joints can be accounted for rather well by the stress field formed by superposing a uniform regional stress field on the predicted thermal stresses the large scale pattern of the early joints in many plutons should be predictable based on a pluton s geometry its age relative to the adjacent rock and knowledge of the regional stress at the time of initial cooling these findings bear on issues pertinent to mining petroleum recovery nuclear waste repository siting and ground water flow

recurrent liquefaction induced failures triggered by 2014 cephalonia greece earthquakes spatial distribution and quantitative analysis of liquefaction potential abstract two earthquakes occurred on january 26 and february 3 2014 of mw 6 1 and mw 6 0 respectively onshore the island of cephalonia greece the environmental effects e g rockfalls liquefaction and ground cracks triggered by the events were widespread at the western part of the island and mainly in the peninsula of paliki the most remarkable characteristics of these two events were the generation of strong ground motion the highest ever recorded in greece and the recurrent liquefaction phenomena at the waterfront areas of lixouri and argostoli in addition the grain size distribution curves of soil samples collected along the seafront area at lixouri indicated a sandy ejecta and are plotted in the range of possibility of liquefaction defined by tsuchida 1971 by taking into account the data provided by three post earthquake field trips that took place immediately after the first and the second earthquake and the information provided by geotechnical boreholes drilled along the shoreline in lixouri a quantitative description of the liquefaction induced deformations and a preliminary failure mode of the waterfront structures in lixouri are presented in this study as an outcome a post liquefaction induced settlement of 16 cm at two sites was computed

coseismic deformation field observations and seismic fault of the 17 november 2015 m 6 5 lefkada island greece earthquake abstract on november 17 2015 07 10 07 utc a strong shallow mw6 5 earthquake occurred on the island of lefkada along a strike slip fault with right lateral sense of slip the event triggered widespread environmental effects at the south and western part of the island while the intensity and severity of these earthquake induced deformations is substantially decreased towards the eastern part of the island relocation of seismicity and inversion of geophysical gps insar data indicate that the seismic fault runs parallel to the west coast of lefkada along the aegean apulia plate boundary the fault plane strikes n20 5 e and dips to east with an angle of about 70 5 coseismic deformation was measured in the order of tens of centimeters of horizontal motion by continuous gps stations of noanet the noa gps network and by insar sentinel 1 a image pairs a coseismic uniform slip model was produced from inversion of insar data and permanent gps stations the earthquake measured mw 6 5 using both the geodetic moment produced by the slip model as well as the pgd relation of melgar et al 2015 grl in the field we observed no significant vertical motion of the shoreline or surface expression of faulting this is consistent with the predictions of the model the interferograms show a large decorrelation area that extends almost along all the western coast of lefkada this area correlates well with the mapped landslides the 2003 2015 pattern of seismicity in the ionian sea region indicates the existence of a 15 km seismic gap offshore nw cephalonia