the dead sea transform fault system abstract a new map showing the major features of the dead sea transform fault system based on seismicity satellite imagery geological maps and bathymetric charts is presented special attention is given to the possible northward continuation of the transform system beneath the mediterranean sea near ed damur south of beirut the map shows the dead sea transform system to be a series of offset overlapping left lateral transform faults with a rhombochasm between each pair the system has similarities with the equatorial fracture zones in the atlantic ocean throughout the dead sea transform system is considered in its regional setting i e as extending from the red sea spreading centre in the south to the eurasian collision zone in the north it is suggested that it may intersect the latter somewhere east of cyprus making that area the northernmost termination of the dead sea transform system

historical earthquake activity of the northern part of the dead sea fault zone southern turkey abstract the northern part of the dead sea fault zone is one of the major active neotectonic structures of turkey the main trace of the fault zone called hacipasa fault is mapped in detail in turkey on the basis of morphological and geological evidence such as offset creeks fault surfaces shutter ridges and linear escarpments three trenches were opened on the investigated part of the fault zone trench studies provided evidence for 3 historical earthquakes and comparing trench data with historical earthquake records showed that these earthquakes occurred in 859 ad 1408 and 1872 field evidence palaeoseismological studies and historical earthquake records indicate that the hacipasa fault takes the significant amount of slip in the northern part of the dead sea fault zone in turkey on the basis of palaeoseismological evidence it is suggested that the recurrence interval for surface faulting event is 506 42 years on the hacipasa fault

geometric changes of plate boundaries along part of the northern dead sea transform geochronologic and paleomagnetic evidence the korazim block an elevated pressure ridge along with the faults bounding the sea of galilee and hula pull apart basins are internal structures of the dead sea transform plate boundary k ar dates and paleomagnetic data from basalt flows and sedimentary strata are utilized to determine the stratigraphy and the deformation of the region the integration of the two methods together with structural data yield high resolution age determination of the stratigraphic sequence and provides insight into the timing and style of deformation the korazim block is covered in its southern and central areas by pliocene basalt flows the cover basalt 5 1 3 6 ma and ruman basalt 2 9 2 2 ma formations and in its northern area by basalts yarda basalt 0 9 0 8 ma and sediments 3 0 2 3 and 1 6 0 9 ma of plio pleistocene age the magnetic polarity of a total of 29 lava flows and intercalated sedimentary strata is mixed the mean magnetic declination of the 29 sites shows an anomalous direction which yields 11 4 4 0 counterclockwise rotation with respect to the expected field the mean inclination of 46 0 4 1 does not significantly deviate from the expected field the anomalous declination is interpreted as the consequence of faulting and block rotation accommodating internal deformation this deformation did not begin before late pliocene to early pleistocene probably not before 0 9 ma and may still be active simultaneous right lateral slip of 50 175 m with a small reverse component of 30 90 m along nw trending faults and 11 counterclockwise rotation created internal deformation of the korazim pressure ridge this deformation is the consequence of left lateral slip along the almagor strand of the dead sea transform subparallel to the plate slip vector thus a compression component was formed which presumably led to the internal deformation of the korazim block the recent deformation of the korazim block in relation to the age of adjacent structures and to the age of the dead sea transform permits temporal resolution of geometric changes which must typify transform boundaries such as the dead sea transform internal structures within transforms may change along with the transform internal geometry and become inactive while new structural features may develop

active faulting in the gulf of aqaba new knowledge from the mw 7 3 earthquake of 22 november 1995 abstract on 22 november 1995 the largest earthquake instrumentally recorded in the area with magnitude m w 7 3 occurred in the gulf of aqaba the main rupture corresponding to the strike slip mechanism is located within the gulf of aqaba which forms the marine extension of the levantine fault also known as the dead sea fault the levantine fault accommodates the strike slip movement between the african plate and the arabian plate the gulf of aqaba itself is usually described as the succession of three deep pull apart basins elongated in the n s direction concerning historical seismicity only two large events have been reported for the last 2000 years but they are still poorly constrained the seismicity recorded since installation of regional networks in the early 1980s had been characterized by a low background level punctuated by brief swarmlike activity a few months in duration three swarms have already been documented in the gulf of aqaba in 1983 1990 and 1993 with magnitudes reaching at most 6 1 m w we suggest that the geometry of the rupture for the 1995 event is related to the spatial distribution of these previous swarms body wave modeling of broadband seismograms from the global network along with the analysis of the aftershock distribution allow us to propose a well constrained model for the rupture process northward propagation of the rupture has been found we have demonstrated that three successive subevents are necessary to obtain a good fit between observed and synthetic wave forms the total seismic moment released was 7 42 10 19 n m the location of the subsevents shows that the three stages of the rupture involve three different segments within the gulf substantial surface breakage showing only normal motion up to 20 cm affecting beachrock was observed along the egyptian coast we show that these ruptures are only a secondary feature and are in no case primary ruptures the stress tensor derived from striations collected in quaternary sediments shows radial extension this result supports landsliding of the beach terraces under the action of the earthquake shaking

crustal shortening in the palmyride fold belt syria and implications for movement along the dead sea fault system an edited version of this paper was published in tectonics by the american geophysical union agu copyright 1990 agu see also http www agu org journals tc http atlas geo cornell edu syria chaimov tectonics 1990 html

comparison of frequency of occurrence of earthquakes with slip rates from long term seismicity data the cases of gulf of corinth sea of marmara and dead sea fault zone summary in this article through the comparison of knowledge relating to historical earthquakes with the understanding of present day earthquake mechanics and overall gps slip rates in the eastern mediterranean region it has been possible to obtain an idea of how frequently large earthquakes may be expected in some parts of the region it has also been possible to make an assessment from these early events of slip rates over a long period of time for the gulf of corinth in greece the marmara sea in turkey and the dead sea fault system as well as deriving long term magnitude frequency relations for these same regions it has been demonstrated that slip rates calculated from historical data are in general comparable to those calculated from gps measurements and field observations while the size of historical earthquakes and their uncertainty can be quantified this permits a more reliable estimation of the long term hazard the calculation of which is the concern of the engineering seismologist it has also been shown that in most cases large earthquakes are less frequent when they are estimated from long term data sets rather than from the instrumental period making the notion of recurrence time and of hazard assessment questionable this study focuses on some of the few areas in the world for which long term macroseism information exists and which facilitate this kind of analysis

reconciliation of san andreas slip discrepancy by a combination of interior basin and range extension and transrotation near the coast measurements of net translation along the neogene san andreas transform boundary between pacific and north american plates as indicated by the global correlation of sea floor magnetic anomalies and by total neogene displacements along strands of the onshore san andreas fault system differ by hundreds of kilometres the apparent motion discrepancy is reconciled for post mid miocene time if both transrotational deformation along the coastal belt of california and basin range extension east of the sierra nevada are taken into account

evidence for prehistoric earthquakes on the superstition hills fault from offset geomorphic features offset geomorphic features along the superstition hills fault show evidence for at least one slip event prior to the 1987 surface rupture and possibly as many as four to five earlier prehistoric earthquakes we documented several geomorphic features that appeared offset by multiple events by making detailed topographic maps offset features were abundant along reaches of the fault with high topographic relief and large displacement slip distribution for the penultimate event as recorded by offset rills streams and shrub coppice dunes is very similar to the slip distribution from the 1987 earthquake through april 1988 this similarity may prove to be fortuitous if afterslip from the 1987 event continues to increase the total slip for this earthquake but if afterslip associated with the 1987 event ceases in the near future then the past two earthquakes were nearly identical in slip and the superstition hills fault may be expected to produce characteristic earthquakes of roughly magnitude 6

field evidences from northern dead sea fault zone south turkey new findings for the initiation age and slip rate abstract the left lateral strike slip dead sea fault zone dsfz extends from the red sea in the south to the east anatolian fault zone eafz in the north this study examines the northern part of the dsfz around amik basin and presents surface and subsurface geological evidence for the quaternary activity and initiation age of the northernmost dsfz the dsfz extends n s in the south of the amik basin where clear geological and morphological evidence exists for faulting geological observations around amik basin analyses of borehole data and electrical resistivity profiles within the amik basin indicate that the activity of the northern dsfz started after pliocene in the amik basin subsurface data in the basin suggest that the dsfz offsets a pre quaternary basin sinistrally by about 7 9 km the offset pre quaternary basin suggests at least 4 94 0 13 mm year slip rate for the northern part of the dsfz the karasu fault zone kfz extends in an en echelon pattern along the western margin of the karasu valley and it transfers the significant amount of slip from dsfz to the eafz

kinematics of the amanos fault southern turkey from ar ar dating of offset pleistocene basalt flows transpression between the african and arabian plates

strain partitioning of active transpression within the lebanese restraining bend of the dead sea fault lebanon and sw syria this material has been published in the journal of the geological society of london the only definitive repository of the content that has been certified and accepted after peer review copyright and all rights therein are retained by the geological society of london copyright 2001 the geological society of london see also http atlas geo cornell edu deadsea publications gomez2007 gsl htm

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

the rachaya serghaya fault system lebanon evidence of coseismic ruptures and the ad 1759 earthquake sequence 1 the rachaya and serghaya faults are the easternmost fault branches of the dead sea transform fault within the lebanese restraining bend they lie east of the yammouneh fault the main strand of the dead sea transform fault within the restraining bend extend along the western and eastern flanks of the anti lebanon range respectively and show left lateral strike slip movement manifested as offset drainage we studied both faults through combined field investigations in geomorphology and paleoseismology young fault scarps mole tracks pressure ridges and offset streams detected along the faults traces attest to recent coseismic ruptures two paleoseismic investigations highlight their seismogenic potential and indicate earthquake recurrence along them the rachaya and serghaya faults are active and the sources of recent historical earthquakes the last of which might be the 30 october 25 november 1759 ms 6 6 and 7 4 earthquake sequence that caused severe damage in the eastern mediterranean region such a possible correlation suggests that the two faults are probably structurally interconnected as movement on one fault may stimulate movement on the other fault in addition both faults may define together an active seismogenic fault system that accommodates some of the regional displacement that takes place within the lebanese restraining bend our results highlight that the seismogenic potential of the rachaya and serghaya faults must be included in any seismic hazard assessment of the region

the somalia plate and the east african rift system present day kinematics summary the motion of the somalia plate relative to the nubia africa arabia and antarctica platcs is re evaluated using a new inversion method based on a monte carlo technique and a least absolute value misfit criterion a subset of the nuvel 1 data set with additional data along the levant fault and in the red sea is used the results confirm that the motion of arabia with respect to africa is significantly different from the motion relative to somalia it is further shown that the data along the sw indian ridge are compatible with a pole of relative motion between africa and somalia located close to the hypothetical diffuse triple junction between the ridge and thc east african rift the resulting africa somalia motion is then compatible with the geological structures and seismological data along the east african rift system assuming a separate somalia plate thus solves kinematic and geological problems around the afar triple junction and along the east african rift

high resolution stratigraphy and multiple luminescence dating techniques to reveal the paleoseismic history of the central dead sea fault yammouneh fault lebanon abstract continuous sedimentation and detailed stratigraphy are key parameters for a complete paleo earthquake record here we present a new paleoseismological study across the main strike slip fault branch of the dead sea fault in lebanon we aim to expand the current knowledge on local paleoseismicity and seismic behavior of strike slip plate boundary faults and to explore the limitations of paleoseismology and dating methods the trench dug in the jbab el homr basin reveals a succession of remarkable very thin 0 1 to 5 cm palustrine and lacustrine layers ruptured by at least 17 earthquakes absolute ages of 4 samples are obtained from three luminescence dating techniques targeting fine grain minerals blue green stimulated luminescence bgsl on quartz and post infrared infrared stimulated luminescence at 225 c on polymineral aliquots led to consistent ages while ages from infrared stimulated luminescence at 50 c on polymineral aliquots appeared underestimated the quartz bgsl ages are 26 9 2 3 ka at 0 50 m depth and 30 8 2 9 ka at 3 65 m depth during this time period of 3 9 ka 0 9 1 ka 14 surface rupturing events occurred with a mean return time of 280 years 0 650 years and probable clustering this return time is much shorter than the 1127 135 years return time previously determined at the yammouneh site located 30 km south although fault segmentation and temporal variations in the earthquake cycle remain possible causes for such different records we argue that the high resolution stratigraphy in jbab is the main factor enabling us to record small deformations related to smaller magnitude events that may have been missed in the rougher strata of yammouneh indeed focusing only on larger events of jbab we obtain a mean return time of 720 years 0 1670 years that is compatible with the yammouneh record

holocene faulting and earthquake recurrence along the serghaya branch of the dead sea fault system in syria and lebanon an edited version of this paper was published in geophysical journal international by blackwell publishing blackwell publishing retains the copyright copyright 2003 blackwell publishing see also http www blackwell synergy com doi abs 10 1046 j 1365 246x 2003 01933 x http atlas geo cornell edu deadsea publications gomez2003 gji htm

new empirical relationships among magnitude rupture length rupture width rupture area and surface displacement source parameters for historical earthquakes worldwide are compiled to develop a series of empirical relationships among moment magnitude m surface rupture length subsurface rupture length downdip rupture width rupture area and maximum and average displacement per event the resulting data base is a significant update of previous compilations and includes the additional source parameters of seismic moment moment magnitude subsurface rupture length downdip rupture width and average surface displacement each source parameter is classified as reliable or unreliable based on our evaluation of the accuracy of individual values only the reliable source parameters are used in the final analyses in comparing source parameters we note the following trends 1 generally the length of rupture at the surface is equal to 75 of the subsurface rupture length however the ratio of surface rupture length to subsurface rupture length increases with magnitude 2 the average surface displacement per event is about one half the maximum surface displacement per event and 3 the average subsurface displacement on the fault plane is less than the maximum surface displacement but more than the average surface displacement thus for most earthquakes in this data base slip on the fault plane at seismogenic depths is manifested by similar displacements at the surface log linear regressions between earthquake magnitude and surface rupture length subsurface rupture length and rupture area are especially well correlated showing standard deviations of 0 25 to 0 35 magnitude units most relationships are not statistically different at a 95 significance level as a function of the style of faulting thus we consider the regressions for all slip types to be appropriate for most applications regressions between magnitude and displacement magnitude and rupture width and between displacement and rupture length are less well correlated and have larger standard deviation than regressions between magnitude and length or area the large number of data points in most of these regressions and their statistical stability suggest that they are unlikely to change significantly in response to additional data separating the data according to extensional and compressional tectonic environments neither provides statistically different results nor improves the statistical significance of the regressions regressions for cases in which earthquake magnitude is either the independent or the dependent parameter can be used to estimate maximum earthquake magnitudes both for surface faults and for subsurface seismic sources such as blind faults and to estimate the expected surface displacement along a fault for a given size earthquake

palaeozoic gas charging in the ahnet timimoun basin algeria the ahnet timimoun basin southern algeria contains significant gas reserves expelled from originally oil prone silurian and frasnian shales the gas is reservoired in devonian and carboniferous clastics in inversion anticlines formed primarily during the hercynian orogeny integration of organic and inorganic geochemical techniques such as afta zfta fluid inclusion analysis vitrinite and chitinizoan reflectance is entirely consistent with gas generation 300 30my immediately prior to or synchronous with the hercynian orogeny data from gas fields has shown the remobilisation of gas during post hercynian tectonics a open quotes two event close quotes heating cooling history is proposed 1 maximum burial and palaeotemperature at ca 300 30my prior to or synchronous with hercynian uplift and cooling 2 cooling from a secondary peak lower than maximum palaeotemperature at ca 30 60my following creataceous burial calibrated thermal modelling indicates that palaeozoic source rocks were heated above 200 degrees c in the late carboniferous such high temperatures are consistent with the widespread occurrence of pyrophyllite in silurian shales two end member thermal models can account for the observed maturities the first is a constant high pre hercynian heat flow which rapidly decreases during hercynian uplift to remain at present day values of 50 75mw m sup 2 gas expulsion in this case commences much earlier thanmore trap formation the second is open quotes normal close quotes heat flow of ca 50mw m sup 2 until ca 310my with a rapid increase at ca 290my followed by an equally rapid drop to constant present day values in this model petroleum generation and expulsion is late in relation to structuring less

a long lived hydrothermal system in bushveld granites at the zaaiplaats tin mine lead isotope evidence tin mineralization at zaaiplaats is hosted in alkali feldspar granites of the lebowa granite suite which intrude the rashoop granophyre suite from the upper contact downward the alkali feldspar granites include the marginal pegmatite fine grained lease granite and the coarse grained bobbejaankop granite the major mineralization styles consist of subhorizontal tabular low grade orebodies in the lease granite a lower zone of disseminated cassiterite mineralization in the bobbejaankop granite and shallowly plunging and branching pipe orebodies in both granites fluid inclusion data show a continuous evolution of the magmatic hydrothermal system from 600 degrees to 200 degrees c with cassiterite and scheelite precipitation above 400 degrees c mineral compositions and oxygen isotope fractionations indicate reequilibration of minerals within the granites during pervasive alteration at temperatures generally between 200 degrees and 300 degrees c the emplacement age of these and other bushveld granites is ca 2050 ma yet pb pb whole rock isochron ages for the different variably mineralized granite bodies at zaaiplaats show a relatively restricted range from 961 or 129 ma for the rashoop granophyre to 1187 or 51 ma for the lease granite thus the analyzed sample suites consistently record an event approximately 1 b y after the emplacement of the granites modeling their pb isotope evolution indicates that each suite evolved independently between 2050 and ca 1100 ma suggesting that hydrothermal fluid circulation was essentially confined within each granite body and or fluid rock ratios were low and that the overall 238 u 204 pb within each suite from 2050 to ca 1100 ma was not unusually high or low for fractionated granites suggesting largely closed system behavior of u and pb within each suite during this interval the ca 1100 ma event which caused closure of the u pb systems at zaaiplaats is interpreted to reflect a blocking temperature age related to uplift and cooling of a long lived hydrothermal system and precipitation of the latest stage minerals e g galena at 200 degrees to 300 degrees c the high steady state temperature required to maintain the hydrothermal system at zaaiplaats at temperatures above 200 degrees c for ca 1 b y was provided by radioactive decay current heat production characteristics calculated from present day u th and k 2 o concentrations range from 4 2 mu w m 3 for the rashoop granophyre to 11 5 mu w m 3 for the lease granite preweathering heat production of 30 3 mu w m 3 is inferred for the mineralized bobbejaankop granite after accounting for dramatic recent losses of u and th the low level of hydrothermal fracturing combined with stable and pb isotope evidence effectively rules out convective cooling by external fluids as a significant heat loss mechanism at zaaiplaats fluid pathways within the granites were controlled dominantly by grain boundaries microfractures and vugs which allowed internal circulation and elevated subsolidus temperatures to be maintained indefinitely under a thermal blanket of an estimated 4 km of postemplacement cover uplift and erosion of the terrain caused cooling through the pb exchange blocking temperatures at ca 1100 ma

quantitative refinement of calibrated 14c distributions abstract a new method is presented for using known ordering or other relationships between 14c samples to reduce 14c dating uncertainty the order of sample formation is often known from for example stratigraphic superposition dendrochronology or crosscutting field relations constraints such as a minimum time between dates and limits from historical information are also readily included dendrochronologically calibrated calendric date histograms initially represent each date the method uses bayes theorem and the relational constraints to upweight date ranges in each date distribution consistent with the other date distributions and the constraints and downweight unlikely portions the reweighted date distributions retain all dating possibilities present in the initial calibrated date distributions but each date in the result now reflects the extra information such as ordering supplied through the constraints in addition one may add information incrementally and thus analyze systematically its effect on all the date distributions thus the method can be used to assess the consistency of the quantitative data at hand the bayesian approach also uses the empirical calibrated date distributions directly so information is not lost prematurely by summarized dates to a mean and variance or confidence intervals the approach is illustrated with data from two densely sampled paleoseismic sites on the san andreas fault in southern california an average reduction in 14 c date distribution variance of 59 is achieved using ordering information alone and 85 is achieved by also applying sedimentation rate constraints and historical information

discontinuous ephemeral streams abstract many ephemeral streams in western north america flowed over smooth valley floors before transformation from shallow discontinuous channels into deep arroyos these inherently unstable streams of semiarid regions are sensitive to short term climatic changes and to human impacts because hillslopes supply abundant sediment to infrequent large streamflow events discontinuous ephemeral streams appear to be constantly changing as they alternate between two primary modes of operation either aggradation or degradation may become dominant attainment of equilibrium conditions is brief disequilibrium is promoted by channel entrenchment that causes the fall of local base level and by deposition of channel fans that causes the rise of local base level these opposing base level processes in adjacent reaches are maintained by self enhancing feedback mechanisms the threshold between erosion and deposition is crossed when aggradational or degradational reaches shift upstream or downstream extension of entrenched reaches into channel fans tends to create continuous arroyos upvalley migration of fan apexes tends to create depositional valley floors with few stream channels less than 100 years is required for arroyo cutting but more than 500 years is required for complete aggradation of entrenched stream channels and valley floors discontinuous ephemeral streams have a repetitive sequence of streamflow characteristics that is as distinctive as sequences of meander bends or braided gravel bars in perennial rivers the sequence changes from degradation to aggradation headcuts concentrate sheetflow a single trunk channel conveys flow to the apex of a channel fan braided distributary channels end in an area of diverging sheetflow and converging sheetflow drains to headcuts the sequence is repeated at intervals ranging from 15 m for small streams to more than 10 km for large streams lithologic controls on the response of discontinuous ephemeral streams include 1 amount and size of sediment yielded from hillslopes 2 infiltration capacity of valley floor alluvium that influences both the unit stream power available for upstream headcut migration and the attenuation of flashy streamflow events by riparian vegetation in sheetflow reaches and 3 cohesiveness of alluvium which affects headcut and streambank morphology and rates of arroyo extension downcutting and widening initiation of arroyo cutting may be too complex to be attributed to a single cause such as change in mean annual precipitation or grazing by livestock but is most likely associated with a decrease in density of protective plant cover on hillsides and along valley floors relatively larger unit stream power makes downstream reaches more susceptible to initial entrenchment during floods than headwaters reaches and favors persistent arroyos entrenchment continues until an equilibrium longitudinal profile is briefly attained then channel widening occurs streambanks are undercut and aggradation begins

transcurrent fault activity on the dead sea transform in lebanon and its implications for plate tectonics and seismic hazard fault activity within the lebanese transpression zone one of the classic examples of restraining bend development on a continental transform is here investigated using dated geomorphological features the northern part of the yammouneh fault commonly considered to be the principal active strand on this part of the dead sea transform has been inactive for the past 5 ma field observations show that basalts dated as late pliocene hi age apparently offset by the yammouneh fault unconformably overlie it the active transcurrent structure is principally perhaps exclusively the roum fault the lebanese transpressive zone has evolved through tune with migration of fault activity these results confirm the overlapping transform hypothesis for the dead sea system require the active triple junction between the transform and the tethyan collision belt to lie offshore se cyprus and have profound implications for assessing seismic hazard hi the levant

present day kinematics of the middle east and eastern mediterranean the middle east and eastern mediterranean regions contain three major strike slip fault zones the dead sea fault zone dsfz and the north and east anatolian fault zones nafz and eafz these accommodate northward motion of the african and arabian plates relative to eurasia and westward motion of the small turkish plate this study deduces an internally consistent solution for the present day kinematics of these plates which is accurate to better than 20 and applicable throughout time since 5 ma by constraining the slip senses and rates on these strike slip fault zones the 7 0 5 mm yr 1 left lateral slip rate on the dsfz is associated with counterclockwise rotation of arabia relative to africa at 0 33 m y 1 around an eulcr pole near 33 n 23 e the nafz takes up counterclockwise rotation of the turkish plate relative to eurasia at 0 83 m y 1 13 around a pole at 31 n 35 5 e with right lateral slip rate 15 mm yr 1 the resulting prediction for the eafz involves 14 mm yr 1 left lateral motion and 2 mm yr 1 of shortening between arabia and turkey the triple junction of africa arabia and turkey is near the city of kahramanmaras this locality contains a narrow promontory bounded by ssw trending left lateral faults at the edges of the arabian and turkish plates which is loosely attached to the african plate moving westward relative to its interior at 4 mm yr 1

high resolution geological record of historic earthquakes in the dead sea basin a 2000 year paleoseismic record of the dead sea area was recovered from a lacustrine sedimentary section the section is being exposed at the ze elim terrace on the shores of the dead sea due to the fast retreat of the lake the section consists of laminated detrital and chemical mainly aragonite sediments that were deposited in the holocene paleo dead sea eight layers in the section show deformed sedimentary structures and are identified as seismites their chronology was determined by radiocarbon dating on organic remains the seismite ages are well correlated with the historically documented earthquakes of 64 and 31 b c and 33 363 1212 1293 1834 and 1927 a d the few historically documented earthquakes that have no correlatives in the ze elim seismite record occurred in times of sedimentary hiatuses at this site e g 749 a d based on modern analogues and the association of similar disturbed layers with syndepositional faults the ze elim terrace seismites indicate m 5 5 earthquakes the average recurrence interval is estimated as 100 300 years and represents slip events on different faults in the dead sea area the ze elim section provides a unique opportunity to correlate two independent and extensive data sets the historical and sedimentary records this study opens the way for better understanding of spatial and temporal distribution of earthquakes along the dead sea transform and elsewhere

episodic behavior of the jordan valley section of the dead sea fault inferred from a 14 ka long integrated catalog of large earthquakes the continuous record of large surface rupturing earthquakes along the dead sea fault brings unprecedented insights for paleoseismic and archaeoseismic research in most recent studies paleoseismic trenching documents the late holocene faulting activity while tectonic geomorphology addresses the long term behavior 10 ka with a tendency to smooth the effect of individual earthquake rupture events m w 7 here we combine historical archaeological and paleoseismic investigations to build a consolidated catalog of destructive surface rupturing earthquakes for the last 14 ka along the left lateral jordan valley fault segment the 120 km long fault segment limited to the north and the south by major pull apart basins the hula and the dead sea respectively is mapped in detail and shows five subsegments with narrow stepovers width 3 km we conducted quantitative geomorphology along the fault measured more than 20 offset drainages excavated four trenches at two sites and investigated archaeological sites with seismic damage in the jordan valley our results in paleoseismic trenching with 28 radiocarbon datings and the archaeoseismology at tell saydiyeh supplemented with a rich historical seismic record document 12 surface rupturing events along the fault segment with a mean interval of 1160 yr and an average 5 mm yr slip rate for the last 25 ka the most complete part of the catalog indicates recurrence intervals that vary from 280 yr to 1500 yr with a median value of 790 yr and suggests an episodic behavior for the jordan valley fault our study allows a better constraint of the seismic cycle and related short term variations late holocene versus long term behavior holocene and late pleistocene of a major continental transform fault

the 1759 earthquake in the bekaa valley implications for earthquake hazard assessment in the eastern mediterranean region analysis of macroseismic data based on primary sources for large though infrequent historical earthquakes ms 6 5 that occurred along an approximately 350 km long segment of the northern part of the dead sea fault system primarily in lebanon and syria for the period 1100 1988 reveals the following 1 ten events occurred in three relatively short periods tens of years with repeat times of 200 350 years 2 the events most probably broke this north segment of the dead sea fault system possibly including the westernmost segment of the east anatolian fault system near the border between syria and turkey 3 the lack of such large events during the past 100 years should not be interpreted to minimize potential earthquake hazard in this region and 4 the ms 7 plus earthquake on november 25 1759 almost certainly produced surface faulting probably along the yammouneh fault in the bekaa valley and caused heavy destruction with great loss of life in numerous villages and towns including safad damascus beirut and baalbek this main event was preceded by a ms 6 plus foreshock on october 30 1759 in the southern part of the epicentral area of the main shock near the towns of safad and qunaitra which were almost totally destroyed with considerable loss of life

seismic behaviour of the dead sea fault along araba valley jordan the dead sea fault zone is a major left lateral strike slip fault south of the dead sea basin the wadi araba fault extends over 160 km to the gulf of aqaba the dead sea fault zone is known to have produced several relatively large historical earthquakes however the historical events are unequally distributed along the fault and only four events have been reported in the araba valley over the last few thousands of years magnitudes estimated from the historical record are probably slightly smaller than that of the m w 7 3 earthquake that struck the gulf of aqaba in 1995 the fault cuts straight across pleistocene to holocene alluvium and shows morphologic evidence for essentially pure strike slip motion regional seismic monitoring reveals little microseismicity along the fault except around the dead sea and gulf of aqaba where the fault splays into complex pull apart basin fault systems we have investigated the fault zone at several sites selected from spot images and the study of aerial photography at the site of the now destroyed tilah castle a well preserved wall dated to be about 1200 yr bp 14 c age on charcoal is cut by the fault and offset by 2 2 m comparison with offset gullies at a nearby site 3 km to the north and at three other sites respectively 25 50 and 65 km to the south reveals that this specific fault displacement is probably related to the last seismic event that ruptured that fault segment possibly in ad 1458 moreover the offset gullies suggest a characteristic slip behaviour with recurring slip of about 1 5 m on average given the 4 2 mm yr 1 slip rate derived for this fault segment we infer that the fault should produce m w 7 earthquakes along some segment in the araba valley about every 200 years the historical period with only four well documented large earthquakes in ad 1068 ad 1212 ad 1293 and ad 1458 thus appears to have been relatively quiescent with a 20 per cent deficit of m w 7 earthquakes however our data do not exclude the possibility of larger m w 7 6 earthquakes or time clustering of earthquakes over longer timespans an alternative seismic behaviour involves m w 7 6 earthquakes about every 6000 years and m w 7 earthquakes about every 250 years the historical catalogue would then appear to be complete for m w 7 earthquakes

coseismic displacements along the serghaya fault an active branch of the dead sea fault system in syria and lebanon examination of the serghaya fault a branch of the dead sea fault system in western syria and eastern lebanon documents late quaternary and recent left lateral fault movements including the probable remnant of a historic coseismic surface rupture carbon 14 dating and the presence of fault scarp free faces in soft late pleistocene lake deposits suggest coseismic slip during the past two or three centuries possibly corresponding with one of the well documented earthquakes of 1705 or 1759 with an estimated holocene slip rate of 1 2 mm a 1 the serghaya fault accommodates a significant part of the active deformation along the arabian african plate boundary these results suggest that multiple active fault branches are involved in the transfer of strain through the lebanese restraining bend

interaction between fault and off fault seismic sources in hazard analysis a case study from israel abstract in this study seismic source characterization ssc for purpose of seismic hazard analysis sha is explored with a focus on the moment balance and interaction between on fault and off fault seismicity for the purpose of this study a homogenous uniform earthquake catalog for israel is first compiled and de clustered gridded seismicity is calculated based on the de clustered catalog using a fixed kernel as well as an adaptive kernel the main faults are represented as planar features and their magnitude frequency distribution is adjusted to match both the geological and the seismological available data a full probabilistic seismic hazard analysis psha is then conducted for the entire state of israel results are presented both in terms of the full spatial distribution in the form of hazard maps as well as at specific point locations near and far from the main sources our results show that based on the available data and balancing seismic moment the characteristic portion of the main seismic sources in israel is larger than the classical 94 suggested by youngs and coppersmith 1985 and is about 96 98 depending on the fault this suggests that the exponential model as currently used in the building code leads to a significant underestimation of hazard we further show that as long as the moment is balanced hazard results are only mildly sensitive to model choices such as size of kernel or type of cutoff between on fault and off fault sources finally we suggest using the adaptive kernel with the fault extract interaction which we believe is the best representation of the currently available geological seismological and geodetic information

late cenozoic uplift of the amanos mountains and incision of the middle ceyhan river gorge southern turkey ar ar dating of the duzici basalt using the ar ar technique we have obtained the first numerical dates for the pleistocene volcanism along the valley of the river ceyhan in the duzici area of southern turkey in the western foothills of the amanos mountains our six dates indicate a single abrupt episode of volcanism at 270 ka we have identified a staircase of 7 fluvial terraces at altitudes of up to 230 m above the present level of the ceyhan using the disposition of the basalt as an age constraint we assign these terraces to cold climate stages between marine oxygen isotope stages 16 and 2 indicating rates of fluvial incision equated to surface uplift that increase upstream through the western foothills of this mountain range at between 0 25 and 0 4 mm a 1 extrapolation of these uplift rates into the axis of the range suggests that the entire 2300 m of present day relief has developed since the mid pliocene a view that we confirm using numerical modelling since 3 7 ma the amanos mountains have formed a transpressive stepover along the northern part of the dead sea fault zone where crustal shortening is required by the geometry using a physics based technique we have modelled the overall isostatic response to the combination of processes occurring including crustal thickening caused by the shortening erosion caused by orographic precipitation and the resulting outward flow of mobile lower crustal material in order to predict the resulting history of surface uplift this modelling suggests that the effective viscosity of the lower crust in this region is in the range 1 2 1019 pa s consistent with a moho temperature of 590 10 c the latter value being in agreement with heat flow data this modelling shows that the nature of the active crustal deformation is now understood to first order at least in this key locality within the boundary zone between the african and arabian plates the structure and geomorphology of which have been fundamentally misunderstood in the past

multimodal method for coseismic landslide hazard assessment abstract regional scale coseismic landslide hazard assessments have traditionally been based on infinite slope analyses considering only a single mode of failure inventories and landslide reconnaissance work have shown a diverse range of coseismic landslide modes with significantly different consequences of failure this paper presents a multimodal approach for regional scale coseismic landslide hazard assessment through a two step procedure the multimodal method explicitly accounts for four general landslide types commonly observed during earthquakes rock slope failures disrupted soil slides coherent rotational slides and lateral spreads first the susceptibility to each landslide mode is evaluated based on topography second coseismic landslide hazards are assessed using mode specific geotechnical models a trial multimodal landslide assessment is presented for the seismically active country of lebanon results show that the computed coseismic landslide hazard closely matches field verified slope activity across different regions of the country exhibiting a range of failure modes these results qualitatively demonstrate the efficacy of the procedure and suggest that multimodal coseismic landslide hazard analysis is especially well suited for regions with varying terrain and where landslide inventories are not available

slip rate on the dead sea transform fault in northern araba valley jordan the araba valley lies between the southern tip of the dead sea and the gulf of aqaba this depression blanketed with alluvial and lacustrine deposits is cut along its entire length by the dead sea fault in many places the fault is well defined by scarps and evidence for left lateral strike slip faulting is abundant the slip rate on the fault can be constrained from dated geomorphic features displaced by the fault a large fan at the mouth of wadi dahal has been displaced by about 500 m since the bulk of the fanglomerates were deposited 77 140 kyr ago as dated from cosmogenic isotope analysis 10 be in chert of pebbles collected on the fan surface and from the age of transgressive lacustrine sediments capping the fan holocene alluvial surfaces are also clearly offset by correlation with similar surfaces along the dead sea lake margin we propose a chronology for their emplacement taken together our observations suggest an average slip rate over the late pleistocene of between 2 and 6 mm yr 1 with a preferred value of 4 mm yr 1 this slip rate is shown to be consistent with other constraints on the kinematics of the arabian plate assuming a rotation rate of about 0 396 myr 1 around a pole at 31 1 n 26 7 e relative to africa

active faulting in the dead sea rift abstract manifestations of late quaternary and holocene faulting were studied in a 500 km long segment of the dead sea transform rift most prominent are left slip faults whose characteristic physiographic features are recognizable along most of the studied segment where these faults bend or are stepped to the left rhomb shaped grabens or pull aparts are produced forming depressions in the reverse situation compressional features such as pressure ridges domes and folds form positive topographic features such structures are combined on a variety of scales ranging from a few hundred meters long to tens of kilometers normal faults sub parallel to the left slip faults produce a trough like valley along much of the dead sea transform but are most prominent along the margins of the large rhomb grabens e g the dead sea trough they apparently record a small component of transverse extension generally their motion is slow young slip did not occur along some segments during the last few 10 4 y elsewhere throws of 10 20 m at least occurred in this period the dead sea transform is seismically active the instrumental and historic records indicate a seismic slip rate of 0 15 0 35 cm y during the last 1000 1500 y while estimates of the average pliocene pleistocene rate are 0 7 1 0 cm y either much creep takes place or the slip rate varies over periods of a few 10 3 y

earthquake deformations in the lisan deposits and seismotectonic implications summary earthquake deformations and induced sedimentary structures preserved in quaternary sediments include faults folds fissures slumps sand boils and other effects of liquefaction such deformations and structures are well preserved in the lisan deposits of the dead sea of most importance are the fold type deformations known as decollement structures which are present all along the eastern side of the lisan and seem to decrease gradually westwards to disappear in the middle of the lisan these may indicate that palaeoearthquakes originating along the araba fault have triggered such structures due to shaking of elastoplastic unconsolidated sediments over gentle slopes dipping to the west preliminary results from studies on decollement structures preserved in a section representing some 1733 years of continuous deposition in the uppermost pleistocene in the vicinity of wadi araba indicate that 1 seismic activity has fluctuated with time average recurrence period is about 340 20yr for earthquakes with magnitudes greater than or equal to 6 5 earthquakes with magnitude greater than 7 seem to have occurred along the araba fault 2 deduced earthquake magnitudes conform to the frequency magnitude relationship log n 5 24 0 68m 3 the deduced seismic slip rate along the araba fault seems to be not less than 0 64 0 04 cm yr 1

slip rate and locking depth from gps profiles across the southern dead sea transform 1 the dead sea transform is a major strike slip fault bounding the arabia plate and the sinai subplate on the basis of two gps campaign measurements 6 years apart at 17 sites distributed in israel and jordan complemented by israeli permanent stations we compute the present day deformation across the southern segment of the dead sea transform the wadi araba fault elastic locked fault modeling of fault parallel velocities provides a slip rate of 4 9 1 4 mm a and a best fit locking depth of 12 km this slip rate is slightly higher than previous results based only on israeli permanent gps stations data which are located west of the fault it is in good agreement with results based on offset geomorphologic and geologic features that average longer periods of time 10 ka to 1 ma projection in itrf2000 reference frame allows using our data combined with results published earlier to further study the kinematics between arabia nubia and sinai systematic combination of euler poles available in the literature in addition to our new set of data shows that a wide range of arabia sinai pole positions and angular velocities predict reasonable slip rate on the dead sea fault we highlight uncertainties of calculating such poles due to the small size of the blocks and their slow relative motion along a short and almost straight strand of the transform fault which lead to a large trade off between pole location and angular velocity

crusader castle torn apart by earthquake at dawn 20 may 1202 the crusader castle of vadum jacob an outpost overlooking the jordan river was deformed during a destructive earthquake triggered by motion along the dead sea transform the m 7 earthquake occurred at dawn 20 may 1202 and offset the castle walls by 1 6 m this exceptional precision in dating and estimating displacement was achieved by combining accounts from primary historical sources by excavating the dead sea transform where it bisects the castle and by dating faulted archaeological strata the earthquakes of october 1759 and or january 1837 may account for the remaining 0 5 m out of a total 2 1 m of offset our study exploits the potential embodied in interdisciplinary historical archaeological geological research and illustrates how detailed histories of seismogenic faults can be reconstructed

current stress and strain rate fields across the dead sea fault system constraints from seismological data and gps observations abstract the stress and strain rate fields characterizing the dead sea fault system are investigated by using seismological and geodetic observations in order to assess spatial variations in the regional stress field we compiled a multidisciplinary dataset of well constrained horizontal indicators by merging all available data reported in literature with the data obtained in this study through weighted stress inversions of focal plane solutions our findings indicate that the state of stress is characterized by the coexistence of a normal faulting stress regime with the primarily strike slip one according to the regional frame illustrated by previous geological and seismological observations an updated velocity field computed from new observations and earlier published data depicts the general left lateral motion of the dead sea fault system well in agreement with previous studies we detected some differences in the slip rate pattern between the northern and the southern sectors of the fault system the geodetic strain rate field highlights how much of the deformation is accommodated along the fault system itself in a narrow region the comparison between the stress and the strain rate directions reveals that both orientations are near parallel clearly indicating that present day crustal stress and ground deformation patterns are chiefly driven by the same tectonic processes

gps constraints on africa nubia and arabia plate motions summary we use continuously recording gps cgps and survey mode gps sgps observations to determine euler vectors for relative motion of the african nubian arabian and eurasian plates we present a well constrained eurasia nubia euler vector derived from 23 igs sites in europe and four cgps and three sgps sites on the nubian plate 0 95 4 8 n 21 8 4 3 e 0 06 0 005 myr 1 we see no significant 1m m yr 1 internal deformation of the nubian plate the gps nubian eurasian euler vector differs significantly from nuvel 1a 21 0 4 2 n 20 6 0 6 e 0 12 0 015 myr 1 implying more westward motion of africa relative to eurasia and slower convergence in the eastern mediterranean the arabia eurasia and arabia nubia gps euler vectors are less well determined based on only one cgps and three sgps sites on the arabian plate the preliminary arabia eurasia and arabia nubia euler vectors are 27 4 1 0 n 18 4 2 5 e 0 40 0 04 myr 1 and 30 5 1 0 n 25 7 2 3 e 0 37 0 04 myr 1 respectively the gps arabia nubia euler vector differs significantly from nuvel 1a 24 1 1 7 n 24 0 3 5 e 0 40 0 05 myr 1 but is statistically consistent at the 95 per cent confidence level with the revised euler vector reported by chu gordon based on a re evaluation of magnetic anomalies in the red sea 31 5 1 2 n 23 0 2 7 e 0 40 0 05 myr 1 the motion implied in the gulf of aqaba and on the dead sea fault dsf by the new gps nubia arabia euler vector i e ignoring possible sinai block motion and possible internal plate deformation grades from pure left lateral strike slip in the gulf and on the southern dsf with increasing compression on the central and northern dsf with relative motion increasing from 5 6 to 7 5 mm yr 1 1m m yr 1 from south to north along the northern dsf i e north of the lebanon restraining bend motion is partitioned between 6 1m m yr 1 left lateral motion parallel to the fault trace and 4 1m m yr 1 faultnormal compression relative motions on other plate boundaries including the anatolian and aegean microplates derived from the gps euler vectors agree qualitatively with the sense of motion indicated by focal mechanisms for large crustal earthquakes m 6 where data are available on fault slip rates on plate bounding faults north anatolian fault east anatolian fault dead sea fault red sea rift they are generally lower than but not significantly different from the full plate motion estimates suggesting that the majority of relative plate motion is accommodated on these structures

constraints on arabian plate motion and extensional history of the red sea analysis of the geologic and geophysical data from the western and northern margin of the arabian plate combined with data from the red sea gulf of aden leads to an interpretation of arabian plate motion that supports an episodic extensional history in the red sea and gulf of aden phase 1 extension began in medial to late eocene and was caused by the nw propagation of the reoriented central indian ridge spreading center it stretched and thinned continental crust along numerous wrench and normal faults that reactivated preexisting structures first phase extension stopped when the arabian plate terminally sutured to eurasia in the medial miocene and halted northward movement of arabia relative to africa the combined african arabian plates moved north more slowly constricting and thickening continental crust in the bitlis zagros sutures while the red sea remained technically quiescent and accumulated salt by the early pliocene continued northward movement was accommodated by lateral extrusion of large continental wedges north of the bitlis zagros sutures this allowed arabia to move northward faster than africa and reopen the red sea where phase 2 extension was expressed by seafloor spreading extension within the red sea gulf of aden rift system has been controlled by the interactions and effects of two factors 1 convergent processes between the north margin of the arabian plate and the eurasian plate to the north and 2 northwest propagation of extension associated with the medial eocene reorganization of the central indian spreading center

changes in holocene paleoseismic activity in the hula pull apart basin dead sea rift northern israel abstract paleoseismic analysis of the azaz fault segment of the dead sea fault northern israel indicates that this region was subjected to intermittent periods of strong seismicity and quiescence during the latest pleistocene and the holocene the azaz fault forms the eastern margin of the hula valley a pull apart basin between two left stepping segments of the dead sea fault the fault is currently inactive but it displaces a 25 30 ka travertine in the northeastern corner of the hula valley and near surface marsh sediments inside the valley two trenches excavated across a 15 20 m high fault scarp near kefar szold expose fluvial and colluvial sequences showing clear evidence of recent tectonics one trench exposes well sorted bedded alluvial sediments comprising two upward fining units each capped by a weakly developed paleosol the sediments were deposited on the down faulted block and are bounded in the east by the fault scarp the second trench uncovers fine colluvial sediments cross cut by a wide fault parallel fissure filled by collapsed sediments in both trenches the lower sedimentary unit is capped by a coarse colluvium containing boulders up to 1 5 m in size the colluvium shows no clear bedding and has a weakly developed paleosol on top optically stimulated luminescence dating of the lower fluvial sequence shows that its age ranges between 12 ka at the base to 6 ka at the top while the middle part of the overlying colluvium is ca 4 8 ka the relation between the lower fluvial units and the fault indicates that at least two large scale earthquakes occurred in the early holocene each one resulting in a 1 1 5 m high fault scarp during this seismically active period no coarse colluvial sediments were deposited along the fault trace and thus the region must have had low tectonic relief the clear contact with the overlying coarse colluvium reflects a middle holocene rapid change to the present high steep relief this change was achieved by frequent strong seismic events which triggered colluvial processes and prevented stratification and soil formation on the slope the soil on the present slope reflects a quiescent period that has lasted at least several hundred years during which stress has accumulated and seismic risk increased

long term earthquake clustering a 50 000 year paleoseismic record in the dead sea graben the temporal distribution of earthquakes in the dead sea graben is studied through a 50 000 year paleoseismic record recovered in laminated sediments of the late pleistocene lake lisan paleo dead sea the lisan represents more than 10 times the 4000 years of historical earthquake records it is the longest and most complete paleoseismic record along the dead sea transform and possibly the longest continuous record on earth it includes unique exposures of seismite beds earthquake induced structures associated with slip events on syndepositional faults the seismites are layers consisting of mixtures of fragmented and pulverized laminae the places where the seismites abut syndepositional faults are interpreted as evidence for their formation at the sediment water interface during slip events on these faults thicker sediment accumulation above the seismites in the downthrown blocks indicates that a seismite formed at the water sediment interface on both sides of the fault scarps modern analogs and the association with surface ruptures suggest that each seismite formed during a m l 5 5 earthquake the 230 th 234 u ages of a columnar section obtained by thermal ionization mass spectrometry give a mean recurrence time of 1600 years of m l 5 5 earthquakes in the dead sea graben the earthquakes cluster in 10 000 year periods separated by quiet periods of similar length this distribution implies that a long term behavior of the dead sea transform should be represented by a mean recurrence of at least 20 000 year record this observation has ramifications for seismic hazard assessment based on shorter records

fault behavior and characteristic earthquakes examples from the wasatch and san andreas fault zones paleoseismological data for the wasatch and san andreas fault zones have led to the formulation of the characteristic earthquake model which postulates that individual faults and fault segments tend to generate essentially same size or characteristic earthquakes having a relatively narrow range of magnitudes near the maximum analysis of scarp derived colluvium in trench exposures across the wasatch fault provides estimates of the timing and displacement associated with individual surface faulting earthquakes at all of the sites studied the displacement per event has been consistently large measured values range from 1 6 to 2 6 m and the average is about 2 m on the basis of variability in the timing of individual events as well as changes in scarp morphology and fault geometry six major segments are recognized along the wasatch fault on the basis of the most likely number of surface faulting events 18 that have occurred on segments of the wasatch fault zone during the past 8000 years an average recurrence interval of 400 666 years with a preferred average of 444 years is calculated for the entire zone geologic data on the distribution of slip associated with prehistoric earthquakes and slip rates along the south central segment of the san andreas fault suggest that the m 8 1857 earthquake is a characteristic earthquake for this segment comparisons of earthquake recurrence relationships on both the wasatch and san andreas faults based on historical seismicity data and geologic data show that a linear constant b value extrapolation of the cumulative recurrence curve from the smaller magnitudes leads to gross underestimates of the frequency of occurrence of the large or characteristic earthquakes only by assuming a low b value in the moderate magnitude range can the seismicity data on small earthquakes be reconciled with geologic data on large earthquakes the characteristic earthquake appears to be a fundamental aspect of the behavior of the wasatch and san andreas faults and may apply to many other faults as well

earthquake damage history in israel and its close surrounding evaluation of spatial and temporal patterns abstract israel was hit by destructive earthquakes many times in the course of history to properly understand the hazard and support effective preparedness towards future earthquakes we examined the spatial and temporal distribution of the resulted damage we described in detail our systematic approach to searching the available literature collecting the data and screening the authenticity of that information we used gis geographic information system to map and evaluate the distribution of the damage and to search for recurring patterns overall it is found that 186 localities were hit 54 of them at least twice we also found that israel was affected by 4 17 8 and 2 damaging earthquakes that originated respectively from the southern central central northern and northern parts of the dead sea transform dst the temporal appearance of the northern earthquakes is clustered the central earthquakes are more regular in time whereas no damage from the north central and the central quakes with the exception of the year 363 earthquake seems to have occurred south of the dead sea region analyzing the distribution of the damage we realized that the number of the damage reports reflects only half of the incidents that actually happened attesting to incompleteness of the historical catalogue jerusalem is the most reported city with 14 entries followed by akko acre tiberias nablus and tyre with 8 7 7 and 6 reports respectively in general localities in the galilee and north of it suffered more severely than localities in central israel with the exception of nablus and the localities along the coastal plain of israel most probably due to local site effects for the sake of hazard management these observations should be considered for future planning and risk mitigation

global positioning system constraints on plate kinematics and dynamics in the eastern mediterranean and caucasus we present and interpret global positioning system gps measurements of crustal motions for the period 1988 1997 at 189 sites extending east west from the caucasus mountains to the adriatic sea and north south from the southern edge of the eurasian plate to the northern edge of the african plate sites on the northern arabian platform move 18 2 mm yr at n25 5 w relative to eurasia less than the nuvel 1a circuit closure rate 25 1 mm yr at n21 7 w preliminary motion estimates 1994 1997 for stations located in egypt on the northeastern part of africa show northward motion at 5 6 2 mm yr also slower than nuvel ia estimates 10 1 mm yr at n2 4 e eastern turkey is characterized by distributed deformation while central turkey is characterized by coherent plate motion internal deformation of 2 mm yr involving westward displacement and counterclockwise rotation of the anatolian plate the anatolian plate is de coupled from eurasia along the right lateral strike slip north anatolian fault naf we derive a best fitting euler vector for anatolia eurasia motion of 30 7 0 8 n 32 6 0 4 e 1 2 0 1 myr the euler vector gives an upper bound for naf slip rate of 24 1 mm yr we determine a preliminary gps arabia anatolia euler vector of 32 9 1 2 n 40 3 1 1 e 0 8 0 2 myr and an upper bound on left lateral slip on the east anatolian fault eaf of 9 1 mm yr the central and southern aegean is characterized by coherent motion internal deformation of 2 mm yr toward the sw at 30 1 mm yr relative to eurasia stations in the se aegean deviate significantly from the overall motion of the southern aegean showing increasing velocities toward the trench and reaching 10 1 mm yr relative to the southern aegean as a whole

long dormancy low slip rate and similar slip per event for the emerson fault eastern california shear zone excavations in a playa along the 1992 rupture of the emerson fault reveal evidence of two paleoseismic events with only one large prehistoric rupture in the past 15 millennia accelerator mass spectrometer radiocarbon ages of charcoal from playa sediments and from fault scarp colluvium directly beneath the playa beds indicate that the last large prehistoric slip event occurred about 9000 ka trench wall exposures revealed clear evidence of at least one pre 9 ka rupture at the playa site the event horizon of this earthquake is between two pedogenic carbonate layers that have radiocarbon ages of 14 8 ka and 24 1 ka implying that the earthquake occurred about 20 000 years b p the actual bracketing ages for this rupture are likely a few thousand years older because of the mean residence time for the pedogenic carbonate and calibration of the 14c ages by 230th dating despite the large uncertainties a dormant period of at least 6 kyr to as much as 13 kyr separates the older event from the 9 ka event because the scarp formed by the penultimate event is similar in height to the scarp formed by the 1992 mw 7 3 landers earthquake the penultimate rupture was at least locally similar in size to the most recent rupture this similarity supports the concept of characteristic slip for the emerson fault preliminary results from paleoseismic studies at other sites on the 1992 rupture suggest that large ruptures occurred on other nearby faults within a few hundred years of this penultimate event on the emerson fault the interseismic period that preceded the 1992 earthquake on the emerson fault was about 40 times longer than the average interval between large events on the nearby san andreas fault therefore in comparison to events on the san andreas fault the 1992 landers earthquake was an exceedingly rare event

a braided strike slip model for the northern continuation of the dead sea fault and its implications for levantine tectonics abstract the assumption that the 100 110 km sinistral displacement on the dead sea fault is transmitted northwards along a single structure the yammouneh fault which runs ne sw across lebanon is here reviewed a number of valid objections to this concept exist a more attractive model supported by the limited data available from the area is that the motion is transmitted along a number of faults on this basis the temporary rightward flexure of the levant fracture through lebanon has given rise to a braided strike slip fault complex the yammouneh serrhaya fault system this model overcomes the objections against the older concept and allows the explanation of the mt lebanon bekaa valley anti lebanon complex in terms of transpressive and transtensive blocks a tentative outline of the cenozoic structural evolution of the area in terms of two or more phases of motion along the levant fracture is presented

geological and geomorphological evidence for the southwestern extension of the east anatolian fault zone turkey abstract the left lateral strike slip east anatolian fault zone eafz is the main structural link between the north anatolian fault zone nafz in north and subduction in the mediterranean sea and the transform dead sea fault zone dsfz in south we studied the southwestern continuation of the eafz using combined field investigations including geomorphology geology and paleoseismology mapping of offset drainages lineaments shutter ridges and fault planes in young geological units suggests existence of active faults between the mediterranean coast and turkoglu where it intersects with the dsfz yumurtalik and toprakkale faults are the main tectonic structures and detailed examination of geological and geomorphological evidences suggest their quaternary activity paleoseismic trenching on these faults provided evidence for at least two surface rupturing events in the last 9 000 yr detailed examination of paleo valleys of the ceyhan river suggests that the course of the river migrated due to the activity of the toprakkale fault obtained geological and geomorphological data indicates that the eafz continues across the amanos mountains and the slip transfer is mainly accommodated by the toprakkale and yumurtalik faults

late holocene relative sea level changes in lebanon eastern mediterranean twenty nine 14 c dates of precise biological sea level indicators from the lebanese coast show evidence for two significant regional crustal uplift episodes during the past 6000 years we elucidate 1 an upper shoreline at ca 120 to 140 cm which lasted from ca 6000 to 3000 bp and 2 a lower shoreline at 80 40 cm developed between the fifth century bc and the sixth century ad these movements are associated with 1 two major seismic crises along the yammuneh fault and the roum tripoli thrust rtt and 2 subsequent seismic events on a series of second order ene trending dextral transpressive faults vertical movements affected north lebanon whilst the coasts of south lebanon generally underwent crustal downlift this is in contrast with relative stability in northern israel suggesting an area of stationary tectonic conditions west of the dead sea rosh hanikra ras nakoura fault the main 14 c age cluster corresponding to the second uplift event may have resulted from fault movements during the early byzantine tectonic paroxysm ebtp between ca 1750 and 2000 bp relative sea level stabilised to present level around 1000 bp 2006 elsevier b v all rights reserved

constraints on the post 25 ka slip rate of the yammouneh fault lebanon using in situ cosmogenic 36cl dating of offset limestone clast fans the most active seismogenic structure along the eastern shore of the mediterranean is the n s trending left lateral levant fault system lfs the plate boundary between arabia and africa in lebanon it forms a 160 km long restraining bend responsible for the uplift of mount lebanon the resulting transpression is partitioned between the offshore tripoli roum thrust and the yammouneh strike slip fault there are few quantitative constraints on the quaternary slip rate along the lfs here we present a direct estimate of the 25 ka mean slip rate on the yammouneh fault mapped offsets of alluvial fans at two sites 50 km apart on the eastern flank of mount lebanon range between 24 2 and 80 8 m about 30 limestone cobbles sampled on these fans yield in situ cosmogenic 36cl exposure ages mostly between 6 and 27 ka a statistical assessment of offsets versus ages provides bounds on the late pleistocene holocene slip rate on the fault 3 8 6 4 mm yr these results are consistent with long term geological inferences confirming that the yammouneh fault is the main strike slip branch of the lfs in lebanon they illustrate both the potential and the difficulties of using in situ cosmogenic 36cl dating of limestone clast fan deposits for deciphering tectonic and geomorphic processes in the mediterranean

12 000 year long record of 10 to 13 paleoearthquakes on the yammouneh fault levant fault system lebanon we present results of the first paleoseismic study of the yammouneh fault the main on land segment of the levant fault system within the lebanese restraining bend a trench was excavated in the yammouneh paleolake where the fault cuts through finely laminated sequences of marls and clays first order variations throughout this outstanding stratigraphic record appear to reflect climate change at centennial and millennial scales the lake beds are offset and deformed in a 2 m wide zone coinciding with the mapped fault trace ten to thirteen events are identified extending back more than 12 kyr reliable age bounds on seven of these events constrain the mean seismic return time to 1127 135 yr between 12 ka and 6 4 ka implying that this fault slips in infrequent but large m 7 5 earthquakes our results also provide conclusive evidence that the latest event at this site was the great a d 1202 historical earthquake and suggest that the yammouneh fault might have been the source of a less well known event circa a d 350 these findings combined with previous paleoseismic data from the zebadani valley imply that the parallel faults bounding the beqaa release strain in events with comparable recurrence intervals but significantly different magnitudes our results contribute to document the clustering of large events on the levant fault into centennial episodes such as that during the eleventh through twelfth centuries separated by millennial periods of quiescence and raise the possibility of a m 7 event occurring on the yammouneh fault in the coming century such a scenario should be taken into account in regional seismic hazard assessments and planned for accordingly

evidence for 830 years of seismic quiescence from palaeoseismology archaeoseismology and historical seismicity along the dead sea fault in syria an edited version of this paper was published in earth and planetary science letters by elsevier science elsevier science retains the copyright to this paper copyright 2003 see also http dx doi org 10 1016 s0012 821x 03 00144 4 http atlas geo cornell edu deadsea publications meghraoui2003 epsl htm

the repetition of large earthquake ruptures abstract this survey of well documented repeated fault rupture confirms that some faults have exhibited a characteristic behavior during repeated large earthquakes that is the magnitude distribution and style of slip on the fault has repeated during two or more consecutive events in two cases faults exhibit slip functions that vary little from earthquake to earthquake in one other well documented case however fault lengths contrast markedly for two consecutive ruptures but the amount of offset at individual sites was similar adjacent individual patches 10 km or more in length failed singly during one event and in tandem during the other more complex cases of repetition may also represent the failure of several distinct patches the faults of the 1992 landers earthquake provide an instructive example of such complexity together these examples suggest that large earthquakes commonly result from the failure of one or more patches each characterized by a slip function that is roughly invariant through consecutive earthquake cycles the persistence of these slip patches through two or more large earthquakes indicates that some quasi invariant physical property controls the pattern and magnitude of slip these data seem incompatible with theoretical models that produce slip distributions that are highly variable in consecutive large events

what can we learn from 20 years of interseismic gps measurements across strike slip faults i use gps interseismic velocities and classic 2d elastic half space models with a screw dislocation to estimate the long term fault slip rate locking depth and the offset between the surface fault trace and the location of the dislocation below the seismogenic zone for 13 segments along 8 major strike slip faults using deduced strike slip rates and the position of the dislocation to normalize the interseismic velocities to facilitate comparison of spatial patterns of deformation i show that no substantial differences can be detected ruling out a large asymmetry in interseismic velocities across the 8 faults used in this study only the carrizo plain segment of the san andreas fault shows a significant asymmetry that cannot be explained by shifting the position of the dislocation at depth relative to the fault trace however the resulting perturbation is less than 10 of total strike slip rate fault traces are usually curved defining a concave side when the dislocation at depth is significantly offset from the fault trace the shift is always toward the block on the concave side of the fault trace this suggests that the fault zone in the lower crust may develop a simpler geometry more consistent with relative motion across the fault than its upper seismogenic part constrained by the structural complexity of the brittle crust since the faults used in this study are at different times in their interseismic period comparing the interseismic velocity fields across them allows identification of possible variations of the interseismic velocities with time when normalized by slip rate and dislocation location all the faults show the same interseismic strain with no significant differences between deduced locking depths these comparisons suggest that if temporal variations occur as suggested by some dynamic earthquake cycle models they are small and below the accuracy of the available geodetic measurements

deformation along the yammuneh the restraining bend of the dead sea transform paleomagnetic data and kinematic implications a simple geometrical model shows that the plate margin along the restraining bend segment of the transform plate boundary be deformed in order to accommodate overlap of the crust this model predicts both the maximum width of the deformed zone and the magnitude of deformation when the general geometry of the plate margin is known as well as the plate slip vector and the amount of cumulative displacement this idea has been tested along the plate margin of the yammuneh restraining bend of the dead sea transform the plate margin has been deformed by nne folding parallel to the restraining bend and by east west trending right lateral strike slip faults paleomagnetic measurements yield counterclockwise rotation of r r 61 0 9 6 and f f 23 4 17 2 the paleomagnetic rotational data and fault kinematic suggest that the mechanism which accommodates regional left lateral shear is simultaneous right lateral strike slip faulting on secondary faults and block rotation the magnitude of deformation is the same as that predicted by the model which is 100 shortening in a direction parallel to the plate slip vector and negligible deformation in a direction parallel to the transform the large amount of rotation implies that probably more than one fault set is involved and present day seismic activity is the current manifestation of this crustal deformation process if this prediction is correct then the current deformation of the plate margin is accommodated by more favorable newly formed nnw right lateral strike slip faults

sources of the large a d 1202 and 1759 near east earthquakes the sources of the may 1202 and november 1759 m 7 5 near east earthquakes remain controversial because their macroseismal areas coincide straddling subparallel active faults in the lebanese restraining bend paleoseismic trenching in the yammouneh basin yields unambiguous evidence both for slip on the yammou neh fault in the twelfth thirteenth centuries and for the lack of a posterior event this conclusion is supported by comparing the freshest visible fault scarps which imply more recent slip on the r chaiya serghaya system than on the yammouneh fault our results suggest that the recurrence of an a d 1202 type earthquake might be due this century as part of a sequence similar to that of a d 1033 1202 possibly heralded by the occurrence of the 1995 mw 7 3 aqaba earthquake the seismic behavior of the levant fault might thus be characterized by millennial periods of quiescence separated by clusters of large earthquakes

source inversion of the 1993 and 1995 gulf of aqaba earthquakes abstract the teleseismic body waves of two earthquakes were inverted to their sources so as to obtain a rupture process for each the events of august 3 1993 m s 6 1 and november 22 1995 m s 7 2 took place at the southern end of the dead sea fault system dsfs which has been seismically quiet for the last few centuries the inversion results show that the rupture of the 1995 event originated in the vicinity of the 1993 event and propagated to the north where the major moment release of two subevents took place the first being 20 km and the second being 40 km away the seismic moment of the first and second subevents were m o 7 4 10 18 nm and m o 38 10 18 nm respectively despite their proximity they show completely different focal mechanisms the first subevent has a predominantly normal faulting mechanism like the 1993 event which probably took place on the faults forming the pull apart basins beneath the gulf of aqaba the major subevent shows a predominantly left lateral strike slip mechanism which clearly identifies the dsfs as accommodating the motion between africa and arabia we attribute the abrupt change of the mechanisms of the 1993 and 1995 events to segmentation of the dsfs beneath the gulf of aqaba which probably gave rise to an extensional regime the locations of the 1993 and 1995 earthquakes their aftershock distribution and the spatial distribution of the subevents of the 1995 earthquake show end to end migration of sources from south to north taking into account the long seismic quiescence of the dsfs and the source inversion results one may conclude that the area to the north of the rupture zone of the 1995 event is prone to a large earthquake