on late miocene to recent vertical motions in the cretan segment of the hellenic arc abstract high resolution foraminiferal and calcareous nannoplankton biostratigraphy and reliable paleobathymetry estimates based on plankton benthos ratios in foraminifera make it possible to reconstruct in detail late neogene vertical motions along the central cretan segment of the hellenic arc these motions are considered to express the surficial effect of the roll back process of the hellenic subduction zone which started about 12 ma ago in contrast to earlier views there is no sustained uplift since the late middle miocene successive paleotopographic profiles for central crete show a predominance of subsidence coupled with an increase of differential reliefs from the latest serravallian until the messinian subsidence was most pronounced between the tortonian messinian boundary interval and the early part of the early pliocene locally up to a magnitude of more than 1000 m a two phased uplift history coupled with tilting to the north or northeast can be inferred from the late early pliocene recent record separated by a short early late pliocene episode of subsidence rates of uplift were highest in the early pliocene up to about 125 cm ka the central cretan late neogene to recent paleotopographic profiles are compared with those reconstructed from seismic interpretations and drilling data from the cretan sea the combined results show that paleotopographic configurations between the cyclades and crete were fairly similar to those on central crete until messinian time foundering of the cretan basin started in the course of the early pliocene but subsidence rates were less than the contemporaneous uplift rates of crete the timing and magnitude of the vertical motions along the cretan sea central cretan transect put detailed geological constraints on tectonophysical modelling of the surficial effects of the roll back process these vertical motions are discussed in view of the model of southward translation of a large supracrustal slab resulting in the origin of the cretan sea and in thrusting and uplift in the frontal parts of the slab where it thrusted over the northern limb of the subducted ionian plate

on the hellenic subduction zone and the geodynamic evolution of crete since the late middle miocene abstract in recent syntheses of the geodynamic evolution of the aegean area the hellenic subduction zone and in particular its initiation plays a central role two basic aspects of the recent comprehensive model put forward by le pichon angelier and co workers are a initiation of subduction along the hellenic arc is inferred to have taken place approximately 13 ma ago whereas several others have suggested approximately 5 ma and b migration of the trench system to the south southwest giving rise to an extensional regime in the back arc region which led to general subsidence and formation of the present day aegean sea new data on the structure of the upper mantle underneath the aegean area indicate that the former aspect requires modification the seismic velocity structure indicating a northward dipping slab down to a depth of at least 600 km and the depth distribution of earthquake hypocenters can not be reconciled with straightforward initiation of subduction approximately 13 ma ago estimates of about 5 ma for the time of initiation of the present subduction zone are even more difficult to reconcile assuming 400 km as an upper bound for the effect of stretching of the aegean sea and of other processes contributing to the separation of crete from the eurasian mainland we arrive at an age for the hellenic subduction zone of at least 26 ma as to aspect b geological data of crete lend strong support to the idea that on crete compressional tectonics is of much greater importance than current models imply combining geophysical and geological data we propose a modification of the tectonic evolution for the cretan segment of the hellenic arc whereas the basic process of extension caused by a migrating trench system roll back in a land locked basin remains a very useful and sound concept the tectonics of the margins of a region subject to stretching in this case crete may be more complicated than hitherto thought in our model the documented fragmentation of crete into several basins which started about 12 ma ago is not attributed to initiation of subduction but to inception of the roll back process compressional tectonics on crete is taken to be associated with deformation of the crust resulting from the overall tensional stress regime

geometry kinematics and deformation rates along the active normal fault system in the southern apennines implications for fault growth throw rates throws and kinematic data have been collected from a localised system of active normal faults in the southern apennines italy to assess how its growth history differs from that for a distributed fault system in the central apennines both show evidence for fault interaction in that 1 faults located centrally along strike have higher throws and throw rates than distal faults and 2 cumulative throw and throw rate profiles summed across strike show central maxima with values decreasing to zero at fault system tips however although throw rates increased through time in the central apennines we are unable to resolve such changes if they exist for the southern apennines specifically throw rates derived from offsets of 18 ka geomorphic surfaces are consistent with total throws in the southern apennines when extrapolated back through time but overestimate total throws in the central apennines by a factor of 2 4 suggesting an increase in throw rate through time for the latter we discuss why some fault systems appear to have throw rates that are constant through time whilst others accelerate during growth interaction

slickenside and fault surface kinematic indicators on active normal faults of the alpine betic cordilleras granada southern spain abstract twenty four mesoscopic slickenside kinematic indicators are described here for the pliocene quaternary active normal faults of the alpine betic cordilleras granada southern spain the indicators are classified into twelve groups depending on the down or up slope asymmetric orientation of features such as concavities damaged versus sharp grain borders or step edges v shaped markings fractures and trailed material seventeen of the indicators were not previously described in the literature the new kinematic indicators include two types of asymmetric grains a carrot shaped marking six substructures of congruous and incongruous steps trailed fault material a drop shaped figure a v shaped marking three types of synthetic hybrid fractures with congruous steps and two varieties of pluck holes we think that some of these kinematic indicators provide information on the amount of displacement aseismic versus seismic slip rates cataclastic flow frictional wear or surface polishing

thrust faults and extensional detachment faults in cretan tectono stratigraphy implications for middle miocene extension abstract the revised tectono stratigraphy of crete and especially of the phyllites quartzites complex demonstrated the distinction of the probable paleozoic low medium grade metamorphic rocks of the arna unit from the underlying permo triassic phyllites and associated carbonate sediments trypali facies of western crete unit as well as the overlying permo triassic phyllites and associated sediments of the tyros ravdoucha beds at the base of the tripolis unit the pre existing mixture of the above tectono stratigaphic units in a single complex created a number of misinterpretations as far as stratigraphy metamorphism and interpretation of low angle faults as thrusts or detachments especially in cases where the inferred tectonic contact concerns the transition between the tyros beds and the base of the tripolis carbonate platform there is no structural omission and therefore the contact represents a minor disharmonic sliding surface and not a detachment based on the revised tectono stratigraphic analysis the determination of the structural omission for each tectonic contact was possible and several detachments were described for the first time footwall rocks of the detachments comprised several tectonic units usually from the lower nappes and hanging wall rocks comprised several tectonic units usually from the upper nappes the detachment may separate not only metamorphosed units in the footwall mani western crete arna from non metamorphosed units in the hanging wall tripolis pindos and higher nappes but also all other possible combinations from the cretan nappe pile extension in crete started in the middle late miocene with the formation of extensional detachment faults the reported extensional structures of oligocene to early miocene age do not correspond to crustal extension of crete but to localized shear zones related to nappe stacking and the exhumation of metamorphic rocks extensional detachments in crete form a tectonic horst through two oppositely dipping e w trending zones one dipping north related to the opening of the cretan basin and the other dipping south related to the formation of the messara supra detachment basin the deformation history of units within crete can be summarized as i compressional deformation producing arc parallel east west trending south directed thrust faults in oligocene to early miocene time ii extensional deformation along arc parallel east west trending detachment faults in middle miocene time with hanging wall motion to the north and south and iii late miocene quaternary transtensional deformation along high angle normal and oblique normal faults that disrupt the older arc parallel structures

slickenside kinematic indicators abstract a new classification of slickenside kinematic indicators is presented based on 61 criteria these slickensides have been subdivided into eleven major groups v or crescentic markings steps fractures trains of inclined planar structures trailed material asymmetric elevations deformed elements mineralogical crystallographic orientations asymmetric plan view features asymmetric cavities and asymmetric folds this classification constitutes a useful tool for geologists interested in the determination of the shear sense in fault surfaces bearing slickensides examples of application of this classification to natural fault surfaces at different scales are presented

tsunami deposits on the coastline of west crete greece abstract the eastern mediterranean and the aegean sea in particular are the most active seismic regions in europe historically numerous earthquakes have occurred in this part of the world and comprehensive tsunami recordings exist nevertheless field evidence of tsunamis is rare although many neotectonic movements certainly must have triggered very strong tsunami waves along the coastlines of western crete we found evidence for tsunami impacts such as 1 bimodal deposits large clasts floating in sands comprised of shell fragments 2 dislocation of large boulders with tilting of biogenous notches and 3 boulders with lithophaga or cliona borings weighing up to 75 tons thrown onshore and imbedded in strata of marine shells this paper documents these deposits and discusses whether they originated from the sudden uplift that occurred in 365 ad moreover numerical radiocarbon ages reveal the occurrence of two tsunamis dated to 5660 yrs bp and 500 yrs bp evidence for other tsunami impacts is discussed but not supported by numerical dating due to the lack of suitable material

canary current and north equatorial current from an inverse box model 1 the large scale canary basin circulation is estimated from a box inverse model applied to hydrographic data from a quasi synoptic survey carried out in september 2003 the cruise consisted of 76 full depth ctd and oxygen stations circulation is required to nearly conserve mass and anomalies of salinity and heat within layers bounded by neutral surfaces it permits advective and diffusive exchange between layers and an adjustment of the ekman transport and the freshwater flux divergences the canary current at the thermocline layer transports a net mass of 4 7 0 8 sv southward north of the canary islands from the african coast to 19 w it is divided into a northward circulation at a rate of 1 1 0 5 sv between the african coast and lanzarote island and a southward transport of 5 8 0 6 sv it transports north atlantic central water and organic matters advected offshore by the filaments protruding from the upwelling system off northwest africa at 24 n the canary current feeds the north equatorial current that transports a mixture of north and south atlantic central waters westward in the intermediate layer a southwestward flow of 1 2 1 1 sv transports mediterranean water to the subtropical gyre though the highest salt flux is transported by a meddy oxygen distribution and mass transport suggest a northeastward deep flow of a water mass colder than 2 2 c consisting of diluted antarctic bottom water the heat and freshwater divergences and the average dianeutral velocity and diffusion between the sections and the african coast are negligible

paleostress states at the south western margin of the central european basin system application of fault slip analysis to unravel a polyphase deformation pattern abstract we analyse the deformation pattern along the south western margin of the central european basin system cebs where upper carboniferous mesozoic rocks are uplifted due to the late cretaceous basin inversion the geometry of mesoscale faults and associated striae are used to calculate the stress state s responsible for the observed deformation each reduced stress tensor obtained comprises i the directions of the principal stress axes 1 2 and 3 1 2 3 and ii the ratio of principal stress differences r 2 3 1 3 we present a stress inversion technique that allows each stress state inherent in a heterogeneous fault population to be identified by integrating the results of the pbt method turner f j 1953 nature and dynamic interpretation of deformation lamellae in calcite of three marbles american journal of sciences 251 4 276 298 sperner b ratschbacher l and ott r 1993 fault striae analysis a turbo pascal program package for graphical presentation and reduced stress tensor calculation computers geosciences 19 1361 1388 and the multiple inverse method yamaji a 2000 the multiple inverse method a new technique to separate stresses from heterogeneous fault slip data journal of structural geology 22 4 441 452 this comprehensive approach not only facilitates the separation of complex data sets into homogeneous subsets but also guarantees that each stress state derived fulfils both the criteria of low misfit angles wallace bott hypothesis and high shear to normal stress ratios mohr coulomb criterion the reliability of our technique is confirmed by the fact that irrespective of i the number of fault slip data from an outcrop ii the number of subsets they represent and iii the proportion of newly formed and reactivated faults we obtain consistent results from outcrops of variously aged rocks this consistency concerns both calculated stress states as well as locally observed deformation sequences such local chronologies are derived from cross cutting relationships and superimposition of different fault slip data which individually are assigned to a consistent stress state a synthesis of results from different locations of the study area argues for the superposition of two main deformation events most prominently the area was affected by a stress state with a horizontal n s to ne sw directed maximum compression 1 and a low stress ratio which induced reverse and strike slip faulting a pure strike slip regime of e w to nw se directed compression with moderate stress ratios is less prevalent and probably younger the age of the youngest rocks documenting these two phases proves the stress fields to correspond to the polyphase late cretaceous tertiary basin inversion of the cebs during post cenomanian times the youngest tectonic imprints detected in the study area correspond to locally appearing extensional stress states with varying directions of 3 at many sites the youngest derived paleostress state coincides with the present day stress field in terms of the direction of the maximum horizontal stress axis s hmax the only stress state detected which pre dates the basin inversion corresponds to an extensional regime with an wnw ese to nw se directed 3 axis observed only locally in the n s striking leine graben and its prolongation to the north the fact that the majority of variously aged rocks exhibit only the traces of the latest deformation phases indicates a high degree of fault plane reactivation in the study area

slip vector analysis with high resolution t lidar scanning abstract a palaeostress analysis of an active bedrock normal fault scarp based on kinematic indicators is reconstructed using terrestrial laser scanning tls for this purpose three key elements are necessary for a defined region i the orientation of the fault plane ii the orientation of the slickenside lineation or other kinematic indicators and iii the sense of motion of the hanging wall the paper specifies a workflow in order to obtain stress data from point cloud data using terrestrial laser scanning tls in an active tectonic environment the entire analysis was performed on a continuous limestone bedrock normal fault scarp on the island of crete greece at four different locations along the wnw ese striking spili fault at each location we collected data with the terrestrial light detection and ranging system t lidar we then validated the calculated three dimensional stress results at three of the locations by comparison with conventional methods using data obtained manually with a compass clinometer numerous kinematic indicators for normal faulting were discovered on the fault plane surface using t lidar data when comparing all reconstructed stress data obtained from t lidar to that obtained through manual compass measurements the degree of fault plane orientation divergence is 005 03 for dip direction and dip the degree of slickenside lineation divergence is 003 03 for dip direction and dip therefore the percentage threshold error of the individual vector angle at each investigation site is lower than 3 for the dip direction and dip for planes and lower than 6 for the strike the maximum mean variation of the complete calculated stress tensors is 005 03

postnappe stacking extension and exhumation of high pressure low temperature rocks in the island of crete greece the island of crete consists largely of nappes of contrasting lithologies and metamorphism that were stacked southward during an oligocene early miocene n s compression with the lower nappes undergoing a high pressure low temperature hp lt metamorphism this was followed by a n s miocene crustal extension that caused thinning of the nappes and uplift of the hp lt metamorphic rocks ductile conditions took place in the lower nappes associated with a retrograde greenschist metamorphism while semiductile to brittle conditions took place in the upper nappes a major normal detachment fault separates the lower and the upper nappes the quartz texture analyses and the symmetry of structures indicate bulk coaxial deformation while the results of strain analysis suggest both constrictional and flattening strains a younger ne sw compression affected both the thinned nappe pile and the late miocene pliocene sedimentary basins finally a pliocene ne sw extension led to further uplift and exhumation of the hp lt metamorphic rocks this cyclic tectonometamorphic process of alternate compression and extension took place during the migration of the hellenic orogenic belt toward the most external units including successive tectonic events

review of earth science research using terrestrial laser scanning abstract the application of advanced remote sensing technologies including terrestrial laser scanning tls to the earth sciences has increased rapidly in the last two decades improving the spatial and temporal resolution of data terrestrial laser scanning units have evolved into a common tool in studies of spectral and structural geology seismology natural hazards geomorphology and glaciology special consideration of the advantages and limitations of tls in each of these fields is discussed in depth in the context of important work published in each field the workflow used in a tls survey is crucial to the success of the survey and field specific earth science workflows are therefore also discussed products based on tls data such as triangulated irregular networks tin and digital surface models dsm are commonplace tools throughout the earth sciences and the use of these tools to measure slip distributions fault geometries aeolian transport river bed morphologies and flows and other research problems is expanded on where appropriate the review concludes with a discussion of recent trends in tls instrument development and their potential impact on the use of tls in the earth sciences in the future

scales of structural heterogeneity within neotectonic normal fault zones in the aegean region abstract structural heterogeneities within neotectonic normal fault zones in the aegean region are important controls on the geomorphic expression of their uplifted footwall blocks contrasting fault rocks and slip plane phenomena corrugations comb fractures slip parallel fractures and pluck holes are responsible for mesoscopic inhomogeneities within fault scarps along strike disruptions in the continuity of fault scarps step over zones step up zones step down zones footwall cross faults and hangingwall cross faults are products of perturbations in slip plane geometry or intersections with transverse faults large scale variations in range front morphology reflect contrasting patterns of deformation within fault zones some major fault zones and many minor fault zones are characterized by a migration of the active slip plane towards the hangingwall resulting in a distributed network of high angle faults and a range front which is stepped in profile the presence of a localized mass of uneroded bedrock hangingwall salients protruding from the hangingwall of some major fault zones results in intense deformation along a principal slip plane and a range front which is ramp like in profile as a consequence of structural heterogeneities within neotectonic normal fault zones fault scarps and range fronts in the aegean region are subject to a temporally and spatially variable pattern of degradation

coseismic and postseismic subsurface displacements and strains for a dip slip normal fault in a three layer elastic gravitational medium a three layer elastic gravitational fault displacement model has been developed using elastic dislocation and employed to examine the effects of rigidity layering gravity and stress relaxation on surface and subsurface displacements fields for a dip slip normal fault within our three layer model layer 1 represents the upper crust layer 2 the lower crust and layer 3 the upper mantle the fault is embedded in the upper crust horizontal as well as vertical displacement components have been determined displacement field changes due to postseismic stress relaxation have been calculated using both the correspondence principle and relaxed rigidity moduli and results are in close agreement the relaxed rigidity method provides an accurate and computationally efficient method of examining postseismic relaxation postseismic relaxation within the lower two layers only gives surface uplift increasing footwall uplift and decreasing hangingwall subsidence and also increases the wavelength of surface vertical displacement postseismic stress relaxation within all three layers i e uniform half space produces a shorter wavelength of surface vertical deformation with respect to the coseismic response moho topography created during coseismic deformation is initially amplified during postseismic relaxation the relaxed moho topography is dependent on the strength of the upper crust as well as the strength of the lower crust and mantle gravity has a significant influence on displacements only at the postseismic stage when the effective rigidity of the lower layers is small coseismic and postseismic normal strains associated with dip slip normal faulting have been examined for a large normal basement fault intersecting the free surface the coseismic horizontal surface strain perpendicular to fault strike is compressive adjacent to the fault and in the footwall and tensile in the hangingwall away from the fault coseismic stress redistribution may generate significant tensile brittle failure of the upper crust adjacent to large basement faults

characterization of fault roughness at various scales implications of three dimensional high resolution topography measurements accurate description of the topography of active fault surfaces represents an important geophysical issue because this topography is strongly related to the stress distribution along fault planes and therefore to processes implicated in earthquake nucleation propagation and arrest to date due to technical limitations studies of natural fault roughness either performed using laboratory of field profilometers were obtained mainly from 1 d profiles with the recent development of light detection and ranging lidar apparatus it is now possible to measure accurately the 3 d topography of rough surfaces with a comparable resolution in all directions both at field and laboratory scales in the present study we have investigated the scaling properties including possible anisotropy properties of several outcrops of two natural fault surfaces vuache strike slip fault france and magnola normal fault italy in limestones at the field scale digital elevation models of the fault roughness were obtained over surfaces of 0 25 m2 to 600 m2 with a height resolution ranging from 0 5 mm to 20 mm at the laboratory scale the 3 d geometry was measured on two slip planes using a laser profilometer with a spatial resolution of 20 m and a height resolution less than 1 m

kinematic indicators on active normal faults in western turkey quaternary normal fault zones in western turkey comprise multiple slip planes and zone parallel layers of fault breccia they also contain several little known kinematic indicators that are probably typical of many formed at shallow levels in extending terrains the recent exhumation by contractors of about 2000 m2 of slip planes in a sse dipping fault zone separating quaternary colluvium from bedrock carbonates at yavansu 7 km se of kusadasi permits an unusually complete inventory of the indicators to be compiled the most spectacular indicators are metre scale 69 w pitching corrugations in slip planes and recemented breccia sheets underlying them corrugations characterized by sinusoidal profiles normal to their long axes and less commonly culminations and depression along their axes possibly developed as a result of upwards propagating slip planes seeking undemanding pathways through heterogeneous fault precursor breccias that formed in advance of tip lines parallel to corrugation long axes are those of gutters flat floored sleep sided channels a few centimetres wide probably related to the abrasion of subslip plane breccia sheets centimetre scale tool tracks scored in the uppermost subslip plane breccia sheet by resistant colluvial clasts are irregular at their proximal ends but distally they swing into alignment with corrugation axes frictional wear striae centimetres long but only a few millimetres wide and pitching 78 w are superimposed on the other slip parallel lineations comb fractures nearly perpendicular to slip planes define an intersection lineation which is normal to corrugation axes fault plane solutions of earthquakes on sse dipping active faults in the west anatolian extensional province indicate that mainly normal combined with minor dextral slip is the dominant mode a conclusion in accord with the sense of slip inferred from the indicators exposed on the yavansu slip planes

faulting and effects of earthquakes on minoan archaeological sites in crete greece abstract examination of damages affecting the buildings of the archaeological sites of phaistos and agia triada southern crete suggests that these minoan settlements were probably destroyed by two major seismic events characterized by mks intensities of ix x and occurred at the end of the protopalatial 1700 bc and the neopalatial 1450 bc periods geological and morphological studies carried out in the neighbouring areas show the occurrence of e w trending quaternary normal fault segments spili and agia galini faults that control the present topography and morphology and exhibit steep young scarps mostly holocene in age these fault segments are related to a nw se extension direction which is consistent with that indicated by the available focal mechanisms of the earthquakes occurring in this area in the last 50 years combining structural and seismic data we can infer that the spili and agia galini fault segments could represent good candidates to be considered active faults generating large earthquakes m 6 5 that were responsible for the damages of phaistos and agia triada this hypothesis suggests that the minoan palatial centres were destroyed by several large earthquakes related to ruptures along distinct fault segments rather than by a single catastrophic event that caused the abrupt destruction of the minoan civilisation in the eastern mediterranean

along strike variations of the slip direction on normal faults insights from three dimensional finite element models normal faults in nature exhibit a systematic variation of the slip direction along strike with pure dip slip at their centres that changes gradually to oblique slip near their tips here we evaluate the variation of the slip direction along normal faults by three dimensional finite element modelling the model results reveal a nearly linear increase of the strike slip component over two thirds of the distance from the fault centre to its tips which results in an increasing obliqueness of the slip vector along strike excluding the fault tips the relationship between lateral slip and fault length can be approximated by a power law function which shows that the strike slip component is proportional to the dip slip and to the fault dip the development of the sinistral and dextral slip components is caused by the orientation of the minimum principal stress which is deflected toward the fault centre in both footwall and hanging wall a comparison with two faults in the central apennines italy shows good agreement between modelled and measured slip vectors the occurrence of converging slip patterns implies that caution is advised when inferring oblique extension regional stress trajectories and palaeostress fields from slip vectors measured away from the fault centre

active faulting on the island of crete greece in order to characterize and quantify the middle late quaternary and ongoing deformation within the southern aegean forearc we analyse the major tectonic structures affecting the island of crete and its offshore the normal faults typically consist of 4 30 km long dipslip segments locally organised in more complex fault zones they separate carbonate and or metamorphic massifs in the footwall block from loose to poorly consolidated alluvial and colluvial materials within the hangingwall all these faults show clear evidences of recent re activations and trend parallel to two principal directions wnw ese and nne ssw based on all available data for both onland and offshore structures morphological and structural mapping satellite imagery and airphotographs remote sensing as well as the analysis of seismic profiles and the investigation of marine terraces and holocene raised notches along the island coasts for each fault we estimate and constrain some of the principal seismotectonic parameters and particularly the fault kinematics the cumulative amount of slip and the slip rate following simple assumptions and empirical relationships maximum expected magnitudes and mean recurrence periods are also suggested summing up the contribution to crustal extension provided by the two major fault sets we calculate both arc normal and arcparallel long term strain rates the occurrence of slightly deeper and more external low angle thrust planes associated with the incipient continental collision occurring in western crete is also analysed although these contractional structures can generate stronger seismic events m 7 5 they are probably much rarer and thus providing a minor contribution to the overall morphotectonic evolution of the island and the forearc a comparison of our geologicallybased results with those obtained from gps measurements show a good agreement therefore suggesting that the present day crustal deformation is probably active since middle quaternary and mainly related to the seismic activity of upper crustal normal faults characterized by frequent shallow 20 km moderate to strong seismic events seldom alternating with stronger earthquakes occurring along blind low angle thrust planes probably ramping from a deeper aseismic detachment ca 25 km this apparently contradicting co existence of juxtaposed upper tensional and lower compressional tectonic regimes is in agreement with the geodynamics of the region characterised by continental collision with nubia and the aegean mantle wedging

neotectonic evolution of the central betic cordilleras southern spain abstract paleostress orientations were calculated from fault slip data of 36 sites located along a traverse through the central betic cordilleras southern spain heterogeneous fault sets which are frequent in the area have been divided into homogeneous subsets by cross cutting relationships observed in the field and by a paleostress stratigraphy approach applied on each individual fault population the state of stress was sorted according to main tectonic events and a new chronology is presented of the miocene to recent deformation in the central part of the betic cordilleras the deviatoric stress tensors fall into four distinct groups that are regionally consistent and correlate with three late oligocene aquitanian to recent major tectonic events in the betic cordilleras the new chronology of the neotectonic evolution includes from oldest to youngest the following main tectonic phases 1 late oligocene aquitanian to early tortonian 1 subhorizontal n s partly e w directed 3 subvertical compressional structures thrusting of nappes large scale folding and strike slip faulting in the alboran domain and the external zone of the betic cordilleras 2 early tortonian to pliocene pleistocene 1 subvertical 3 subhorizontal nw se partly n s directed or e w directed radial extension large scale normal faulting in the central betic cordilleras and in the oldest neogene formations of the granada basin related to the gravitational collapse of the betic cordilleras and the exhumation of the intensely metamorphosed rock series of the internal zones at the same time formation of the alboran basin and intramontane basins such as the granada basin 3 pleistocene to recent 3a 1 subvertical 3 subhorizontal ne sw with prominent normal faulting but coevally 3b 1 subhorizontal nw directed 3 ne sw subhorizontal with strike slip faulting extensional structures and strike slip faulting are related to the ongoing convergence of the eurasian and african plates and coeval uplift of the betic cordilleras reactivation of pre existing fractures and faults was frequently observed phase 3 is interpreted as periodic strike slip and normal faulting events due to a permutation of the principal stress axes mainly 1 and 2

identifying past earthquakes on carbonate faults advances and limitations of the rare earth element method based on analysis of the spili fault crete greece abstract recent work carcaillet et al 2008 manighetti et al 2010 has utilised a well established earthquake record on a normal fault in italy the magnola fault to successfully test a new method for identifying paleoearthquakes on carbonate rocks that of chemical analysis of their exhumed fault planes here we take the next natural step applying this novel method on a notionally active normal fault in greece the spili fault for which no paleoearthquake record exists despite the blind sampling data reveal an outstanding record of systematic fluctuations in the concentrations of rare earth elements ree and yttrium y upscarp which closely resemble those recorded on the magnola fault chemical analysis of 35 core samples extracted from a 10 m high section of the exhumed spili fault plane records upscarp depletion in the ree y concentrations at an average rate of ca 9 3 m depletion is overprinted by locally increased ree y concentrations upscarp a minimum of four such concentration fluctuations with wavelengths ranging from 0 5 to 3 m are recorded each fluctuation is interpreted to be generated by at least one paleoearthquake that episodically exhumed a zone of the fault plane each zone consists of an upper domain that is enriched in ree y and a lower un enriched domain ree y enrichment is due to the prolonged at least few 100 s of years contact of the limestone with the soil whereas the un enriched domain reflects instantaneous uplift from depths greater than the base of the soil during the same earthquake the ree y analytical method cannot resolve individual small sized earthquakes with slip less than the thickness of the soil cover and or individual large and small sized earthquakes which are clustered in time repeat time

the ad 365 crete earthquake and possible seismic clustering during the fourth to sixth centuries ad in the eastern mediterranean a review of historical and archaeological data abstract historical and archaeological data are used to test geological claims that in the fourth to sixth centuries ad the eastern mediterranean experienced an unusual clustering of destructive earthquakes the early byzantine tectonic paroxsym a review of historical accounts of a notable earthquake at this time that of 21 july ad 365 indicates that this event destroyed nearly all the towns in crete and was followed by a tsunami which devastated the nile delta the ad 365 event was also probably responsible for reported or observed destruction in ancient towns of west cyprus and libya this earthquake is most likely to be identified with a hellenic arc subduction zone event of great m 8 magnitude as testified by up to 9 m of uplift in western crete dated by previous geological studies to around this time historical and archaeological data also support the hypothesis that the fourth to sixth centuries ad was a period of abnormally high seismicity in the eastern mediterranean the high seismicity rates of this period may reflect a reactivation of all plate boundaries in the region dead sea transform east anatolian fault north anatolian fault hellenic arc cyprus arc fault

spatial and temporal variations in growth rates along active normal fault systems an example from the lazio abruzzo apennines central italy abstract the geometry kinematics and rates of active extension in lazio abruzzo italian apennines have been measured in order to gain a better understanding of the spatial and temporal variations in fault growth rates and seismic hazards associated with active normal fault systems we present fault map traces throws throw rates and slip directions for 17 parallel en echelon or end on active normal faults whose 20 40 km lengths combine to form a soft linked fault array ca 155 km in length and ca 55 km across strike throw rates derived from observations of faulted late glacial features and holocene soils show that both maximum throw rates and throw rate gradients are greater on centrally located faults along the strike of the array total throws and throw gradients show similar spatial variations but with weaker relationships with distance along strike when summed across strike throw rates are increasingly high towards the centre of the array relative to summed throws we interpret the above to suggest that throw rates have changed in the recent past ca 0 7 ma from spatially random fault growth rates initiating at 2 5 3 3 ma to growth rates that are greater on centrally located faults we interpret this as evidence for fault interaction producing throw rate variations that drive throw profile readjustment on these crustal scale soft linked faults the results are used to discuss seismic hazards in the region which are quantified in a second paper in this issue

field permeability of the weathered champlain clay crust this paper discusses methods for evaluating the coefficient of permeability k of the weathered and fissured champlain clay crust this parameter is important because losses due to seepage from fluid retaining structures are directly porportional to the value of k the presence of fissures complicates its evaluation and conventional techniques produce questionable results for two reasons clogging of fissures by the smearing of the clay on the walls of test holes during drilling and insertion of a probe leads to an underestimation of k and conversely hydraulic fracturing caused by the application of excessive heads leads to an overestimation of k a new technique is presented that prevents the smearing of the clay by reaming the walls of a prebored auger hole falling head and constant head tests were performed with feeding devices using a large range of heads including low values results confirm that hydraulic fracturing occurs when a critical value of head is reached as a result the use of the low