description of a partial dromiceiomimus dinosauria theropoda skeleton with comments on the validity of the genus dromiceiomimus brevitertius is a north american ornithomimid diagnosed primarily by the ratio of tibia length to femur length it has recently and perhaps incorrectly been considered synonymous w

advection and dispersion of contaminant in a permeable medium embedding fractures in which advection velocity is comparatively slow abstract this paper concerns the advective migration of an aqueous contaminant in a fractured permeable formation calculation and analysis refer to fractures in which advection velocity is comparatively small the slow advective velocity is created by some local cavities or almost vertical orientation of the fractures it is shown that the advective contaminant transport is characterized by two dimensionless parameters 1 the ratio between the permeable block and fracture flow rates termed the mobility number 2 the ratio between the longitudinal advection velocity of the permeable block flow and that of the fracture flow termed the advection velocity ratio for a sufficiently large domain continuum parameters can be applied to characterization of the fractured permeable formation then the mixing between the permeable block flow and the fracture flow is a mechanism leading to contaminant dispersion for very small values of the advection velocity ratio the effective dispersivity is fully determined by the mobility number its value decreases with increase of the mobility number under such conditions the equivalent porosity is constant and its value is identical to that of the permeable blocks a significant value of the advection velocity ratio increases the equivalent porosity of the fractured permeable formation with regard to the effective dispersivity of the domain if the advection velocity ratio is equal to unity then the effective dispersivity vanishes the larger the deviation of the advection velocity from unity the larger is the effective dispersivity of the fractured permeable medium

an inverse problem for the determination of the stress tensor from polyphased fault sets and earthquake focal mechanisms abstract a new method for determining the stress tensor from fault slip data is presented the solution is obtained by minimizing the deviation between the stress ratio and a value corresponding to the maximum of a probability density function the method can be used to separate successively different tectonic phases and is developed for calculating the stress tensor from earthquake focal mechanisms

a nearly complete skeleton of a new troodontid dinosaur from the early cretaceous of the ordos basin inner mongolia people s republic of china an articulated skeleton of a 1 m long theropod from early cretaceous strata in inner mongolia is clearly referrable to the troodontidae representing the most complete specimen known of this group of small carnivorous dinosaurs the tail and neck of the animal were curled next to its body upon burial the upper surface of the skeleton was badly damaged by erosion previously unknown details of troodont morphology include a quadratic contact with the braincase wall forming part of a channel leading to the lateral depression a presacral vertebral count possibly similar to that of most theropods absence of ossified caudal tendons presence of a rod like clavicle and absence of sternal ossifications a new genus and species sinornithoides youngi n gen n sp is established for the specimen on the basis of its short skull laterally directed orbital rim of the frontal and elongated hind limb a reassessment of character distributions in other small theropods and primitive birds must be completed befor

preliminary interpretation of tracer experiments conducted in a discrete rock fracture under conditions of natural flow the authors present a preliminary analysis of tracer experiments conducted on a natural horizontal fracture system in shale and limestone at a depth of roughly 10 m an array of 27 boreholes on 5 m spacings was placed into this fracture system and apertures of the fractures were determined hydraulically at each hole a conservative tracer was injected into one borehole and monitored in the array the tracer transport process was modeled by a one dimensional model and indicates that transverse dispersion and diffusion in the matrix are the predominant processes which inhibit tracer migration and result in spreading

interpretation of field tracer tests of a single fracture using a transient solute storage model the results and interpretation of five induced gradient tracer tests performed at five different average interborehole fluid velocities in a single fracture in monzonitic gneiss are described the experiments were conducted using radioactive 82br and a fluorescent dye as conservative tracers where the tracers were pulse injected into radial convergent and injection withdrawal flow fields the flow fields were established between straddle packers isolating the fracture in three boreholes over distances of 12 7 29 8 m the tracer breakthrough curves were determined from samples of the withdrawn groundwater and were interpreted using residence time distribution rtd theory and two deterministic simulation models the rtd curves of the tracer experiments were interpreted by fitting to the field data a simple advection dispersion model and an advection dispersion model with transient solute storage in immobile fluid zones both models consider the different flow field geometries associated with injection withdrawal and radial convergent tests comparison of the fits obtained by the simulation models suggest that the initial period of solute transport in single fractures is advection dominated and with increasing tracer residence time or decreasing fluid velocity transport progresses toward more fickian like behavior during the advective dominated period the transient solute storage model is shown to adequately describe the asymmetries and long tails characteristic of the fracture rtds interpretation of the tracer experiments using both simulation models further suggests that induced gradient tracer experiments are likely to underestimate the dispersive characteristics of single fractures under natural flow conditions

reexamination of a primitive ornithomimosaur garudimimus brevipes barsbold 1981 dinosauria theropoda from the late cretaceous of mongolia the holotype of garudimimus brevipes discovered from the upper cretaceous sediments of mongolia and named by barsbold in 1981 is redescribed in detail in this paper reexamination of the holotype reveals a great deal of anatomical information which allows us to revise the original diagnosis of this taxon and make comparisons with other ornithomimosaur taxa to understand the evolution of ornithomimosaurs this paper suggests that characters used to differentiate this taxon in the original paper short ilia short metatarsals exposure of the proximal end of metatarsal iii presence of pedal digit i and absence of pleurocoels are not apomorphies but represent the primitive conditions in ornithomimosaurs and are symplesiomorphies revised diagnoses are assigned for g brevipes posteriorly positioned jaw articulation fossae at base of dorsal process of supraoccipital paired depressions on neural spines of proximal caudal vertebra and deep groove on lateral surface of pedal phalanges iii 1 and iii 2 metatarsals of garudimimus display a non arctometatarsalian condition as in an early cretaceous form harpymimus but the constriction of metatarsal iii in garudimimus is intermediate between harpymimus and the arctometatarsalian condition in gallimimus and other derived ornithomimosaurs ornithomimids garudimimus is the only non ornithomimid ornithomimosaur with edentulous jaws which were probably covered by rhamphothecae the loss of teeth with evolution of rhamphothecae and development of a cutting edge in the dentary of garudimimus suggest the acquisition of feeding habits that included plucking food at the anterior portion of the jaw and cutting at the middle portion similar to ornithomimids resume l holotype de garudimimus brevipes decouvert dans des roches sedimentaires du cretace superieur de mongolie et nomme par barsbold en 1981 est decrit a nouveau en detail un nouvel examen de l holotype revele une quantite considerable d information anatomique qui permet de reviser l interpretation taxonomique originale et de comparer le specimen a d autres taxons des ornithomimosaures afin de mieux comprendre leur evolution il est suggere que les caracteres utilises pour distinguer ce taxon dans l article original la faible longueur des os iliaques et des metatarsiens l exposition de l extremite proximale du metatarsien iii la presence du doigt i du pied et l absence de cavites pleurocoeles ne sont pas des caracteres apomorphiques mais bien des caracteres primitifs et symplesiomorphes des ornithomimosaures des diagnostics revises sont attribues a garudimimus brevipes articulation mandibulaire en

time intervals to assess active and capable faults for engineering practices in italy abstract the time span necessary to define a fault as active and capable can mainly be derived from the framework of the regulations and the literature produced since the 1970s on risk estimation in engineering planning of strategic buildings within this framework two different lines of thought can be determined which have mainly developed in the usa on the one side there is a tendency to produce narrow chronological definitions this is particularly evident in the regulatory acts for the planning of nuclear reactors the much more effective second line of thought anchors the chronological definitions of the terms active and therefore capable to the concept of seismotectonic domain as the domains are different in different regions of the world the chronological definition cannot be univocal i e different criteria are needed to define fault activity which will depend on the characteristics of the local tectonic domain and of the related recurrence times of fault activation current research on active tectonics indicates that methodological aspects can also condition the chronological choice to define fault activity indeed this practice implies the use of earth science methods the applications of which can be inherently limited for example limits and constraints might be related to the availability of datable sediments and landforms that can be used to define the recent fault kinematic history for the italian territory we consider two main tectonic domains a the compressive domain along the southern margin of the alpine chain and the northern and northeastern margins of the apennines which is characterised by the activity of blind thrusts and reverse faults and b the extensional domain of the apennines and the calabria region which is often manifest through the activity of seismogenic normal and normal oblique faults in case a the general geomorphic and subsurficial evidence of recent activity suggests that a reverse blind fault or a blind thrust should be considered active and potentially capable if showing evidence of activity during the quaternary i e over the last 2 6 myr unless information is available that documents its inactivity since at least the last glacial maximum lgm ca 20 ka the choice of the lgm period as the minimum age necessary to define fault inactivity is related to practical aspects the diffusion of the lgm deposits and landforms and to the evidence that ca 20 kyr to assess fault inactivity precautionarily includes a number of seismic cycles in the extensional domains of the apennines and calabria region the general geological setting suggests that the present tectonic regime has been active since the beginning of the middle pleistocene therefore we propose that a normal fault in the italian extensional domain should be considered active and capable if it displays evidence of activation in the last 0 8 myr unless it is sealed by deposits or landforms not younger than the lgm the choice of the lgm as the minimum age to ascertain fault inactivity follows the same criteria described for the compressive tectonic domain

field measurement of radial solute transport in fractured rock the results of a tracer experiment conducted in a single fracture are interpreted using a semianalytical model which accounts for advective dispersion matrix diffusion mixing in the test zones and for tortuosity the experiment was conducted using a conservative tracer which was injected into a steady divergent flow field arrival of tracer was monitored in an array of 13 boreholes intersecting the fracture over a square area of approximately 30 m on a side the arrival of tracer was detected in 11 of the 13 boreholes simulation of the transport process suggests that matrix diffusion may play a significant role in the migration of solutes contrary to previously published results the relative influence of advective dispersion was found to be increasingly diminished with increasing scale fracture apertures determined from the results of the tracer experiment were found to be in general agreement with apertures calculated from independent hydraulic tests the individual advective processes that contribute to advective dispersion remain unresolved on the basis of this experiment

the mineralization of dinosaur soft tissue in the lower cretaceous of las hoyas spain the mineralized soft tissue of a dinosaur only the second discovery of its kind is reported from the lower cretaceous of las hoyas spam cellular details of mineralized skin and muscle of pelecanimimus are replicated in an iron carbonate the outline of this ornithomimosaur is preserved by a phosphatized microbial mat that enshrouded the carcass it confirms the existence of either a throat pouch or dewlap and soft occipital crest this study confirms the importance of microbial mats hi the fossilization of soft tissues and emphasises the need for careful monitoring of vertebrate remains for mineralized soft tissues prior to acid preparation the multitoothed ornithomimosaur dinosaur pelecanimimus polyodon was recently described from the lower cretaceous lacustrine lithographic limestones of las hoyas cuenca spain perez moreno et al 1994 the only known specimen of this the first ornithomimosaur theropod found in europe preserves what were originally described as 9integumentary impressions9 these occur in the throat region flanking the more proximal neck vertebrae in the vicinity of the ribs and behind the elbow in addition a small triangular area at the rear of the skull was interpreted as a possible occipital crest perez moreno et al 1994 analyses confirm that these features represent mineralized traces of soft tissues they are preserved both as replicas of the original skin and muscle tissue and as impressions on microbial mats or veils that grew over them in addition to pelecanimimus the lacustrine limestones of las hoyas melendez 1995 have yielded a well preserved diverse biota of plants

seismotectonics of the calabrian arc abstract relocation of intermediate and deep earthquakes of tyrrhenian sea area through joint hypocenter determination for the period 1962 1979 has allowed a more detailed definition of the geometry of this peculiar benioff zone earthquakes dip along a quasi vertical plane to 250 km depth there is a 50 dip in the 250 340 km depth range and a low dip angle to 480 km depth the structure sketched from the hypocenters is almost continuous but most energy has been released in the 230 340 km depth interval an evaluation of fault plane solutions of intermediate earthquakes in this area indicates predominance of down dip compressions in the central part of the slab at the border strike slip motion occurs independent of depth some earthquakes that occurred at intermediate depth less than 100 km along the ionian margin of calabria show predominance of reverse faulting with the p axis oriented se nw however shallow earthquakes in the calabria sicily region indicate a more complex motion with predominance of normal faulting a possible interpretation of these features according to the available geological history which involves subduction of continental lithosphere is discussed

irpinia italy 1980 earthquake waveform modelling of strong motion data summary several strong motion records of the irpinia southern italy 1980 earthquake have been modelled for a total time duration of about 180 s with the use of the rnultimode summation of waves of p sv and sh type if waveform modelling is applied to unfiltered accelerations the best that can be done at present is amplitude envelope matching in time and frequency domain the early phase of the studied event can be synthesized by 12 main episodes of different sizes modelling the rupturing process the space time distribution of such episodes suggests that the rupturing process did propagate in a bilateral fashion this model of the seismic source gives rise to synthetic velocity records which match quite well the experimental ones to avoid the problems connected with the large instability of displacements obtained from direct numerical integration of observed accelerograms the synthetic signals can be first used to perform acceleration or velocity fitting of experimental data an estimate of the ground displacement above 1 hz can then be obtained by analytical integration of the synthetic velocities

convergent radial dispersion a laplace transform solution for aquifer tracer testing a laplace transform solution was obtained for the injection of a tracer in a well situated in a homogeneous aquifer where steady horizontal radially convergent flow has been established due to pumping at a second well the standard advection dispersion equation for mass transfer was used as the controlling equation for boundary conditions mass balances that account for mixing of the tracer with the fluid residing in the injection and pumped wells were used the derived solution which can be adapted for either resident or flux averaged concentration is of practical use only for the pumped well this problem is of interest because it is easily applied to field determination of aquifer dispersivity and effective porosity breakthrough curves were obtained by numerical inversion of the laplace transform solution it was found that tracer mixing with fluid in the pumped and injection wells especially in low porosity aquifers may have a significant influence on the shape of the tracer breakthrough curves

the interpretation of a tracer experiment conducted in a single fracture under conditions of natural groundwater flow the development of conceptual models to describe the hydrogeology of sparsely fractured media requires the characterization of the properties of discrete fractures at the field scale in this study a tracer experiment conducted under conditions of natural groundwater flow in a discrete fracture in an interbedded shale and limestone sequence is interpreted this experiment which was initiated by injecting a small quantity of tracer into the fracture plane involved monitoring tracer movement using 27 boreholes within a 35 40 m area test data revealed a tracer plume which spread both longitudinally and transversely in the direction of mean groundwater flow the field breakthrough curves were interpreted using a two dimensional finite element transport model that incorporated longitudinal and transverse dispersion diffusion into the rock matrix and constant fracture aperture additional simulations which incorporated the effects of aperture variability were conducted in a monte carlo format by varying the spatial correlation and variance of the aperture field the constant aperture analysis found that the mean aperture determined from the tracer experiment was approximately 20 greater than the mean aperture measured by hydraulic methods values of matrix porosity ranging between 1 and 3 a constant longitudinal dispersivity of 0 1 m and a large range in transverse dispersivity from 0 01 to 0 22 m were required to simulate the data trends of increasing aperture and matrix porosity with distance were observed suggesting that tracer transport followed increasingly tortuous pathways although the variable aperture simulations were not fitted to the field data the aperture field having an isotropic spatial correlation length of 0 5 m and variance of 10 000 m2 provided simulated plumes that appeared to be most similar to the shape and concentration of the field plume evidence from the hydraulic measurement of the aperture distribution suggests that this is a reasonable estimate of the natural aperture field

tracer movement in a single fissure in granitic rock some experimental results and their interpretation radionuclide migration was studied in a natural fissure in a granite core the fissure was oriented parallel to the axis in a cylindrical core 30 cm long and 20 cm in diameter the traced solution was injected at one end of the core and collected at the other breakthrough curves were obtained for the nonsorbing tracers tritiated water and a large molecular weight lignosulphonate molecule and for the sorbing tracers cesium and strontium from the breakthrough curves for the nonsorbing tracers it could be concluded that channeling occurs in the single fissure a dispersion model based on channeling is presented the results from the sorbing tracers indicate that there is substantial diffusion into and sorption in the rock matrix sorption on the surface of the fissure also accounts for a part of the retardation effect of the sorbing species a model which includes the mechanisms of channeling surface sorption matrix diffusion and matrix sorption is presented the experimental breakthrough curves can be fitted fairly well by this model by use of independently obtained data on diffusivities and matrix sorption

a solute transport model for channelized flow in a fracture recent experimental and theoretical investigations of transport in fractures indicate that water flows preferentially through channels in the fracture plane this channeling of flow may imply that solutes transported in large aperture channels have limited exposure to the bulk of the rock matrix surface which contacts the fracture we present a solute transport model for large aperture channels that includes both mass transfer to small aperture regions of the fracture and the adjacent rock matrix to investigate the interaction of solute in large aperture channels with the surrounding rock mass modeling channels similar to those observed in the crystalline rock at the stripa mine show that solute can be retarded considerably due to mass exchange between the channels the small aperture regions of the fracture and the rock matrix the extent of solute retardation is insensitive to the solute capacity in the small aperture regions and the areal spacing between channels in the fracture plane but is very sensitive to the mass transfer rates between the channel and the small aperture region

geomorphic evidence of quaternary tectonics within an underlap fault zone of southern apennines italy abstract a composite seismic source the irpinia agri valley fault zone located in the axial sector of the fold and thrust belt of southern apennines italy is investigated this composite source is made up of a series of nearly parallel nw striking normal fault segments which caused many historical earthquakes two of these fault segments known as the san gregorio magno and pergola melandro and the fault related mountain fronts form a wedge shaped right stepping underlap fault zone this work is aimed at documenting tectonic geomorphology and geology of this underlap fault zone the goal is to decipher the evidence of surface topographic interaction between two bounding fault segments and their related mountain fronts in particular computation of geomorphic indices such as mountain front sinuosity s mf water divide sinuosity s wd asymmetry factor af drainage basin elongation b s relief ratio r h hypsometry hi normalized steepness k sn and concavity is integrated with geomorphological analysis the geological mapping and structural analysis in order to assess the recent activity of the fault scarp sets recognized within the underlap zone results are consistent with the nw striking faults as those showing the most recent tectonic activity as also suggested by presence of related slope deposits younger than 38 ka the results of this work therefore show how the integration of a multidisciplinary approach that combines geomorphology morphometry and structural analyses may be key to solving tectonic geomorphology issues in a complex fold and thrust belt configuration

comment on the southern italy earthquake of 23 november 1980 an unusual pattern of faulting by r s crosson m martini r scarpa and s c key

quantifying diffusive mass transfer in fractured shale bedrock a significant limitation in defining remediation needs at contaminated sites often results from an insufficient understanding of the transport processes that control contaminant migration the objectives of this research were to help resolve this dilemma by providing an improved understanding of contaminant transport processes in highly structured heterogeneous subsurface environments that are complicated by fracture flow and matrix diffusion our approach involved a unique long term steady state natural gradient injection of multiple tracers with different diffusion coefficients br he ne into a fracture zone of a contaminated shale bedrock the spatial and temporal distribution of the tracers was monitored for 550 days using an array of groundwater sampling wells instrumented within a fast flowing fracture regime and a slow flowing matrix regime the tracers were transported preferentially along strike parallel fractures with a significant portion of the tracer plumes migrating slowly into the bedrock matrix movement into the matrix was controlled by concentration gradients established between preferential flow paths and the adjacent rock matrix observed differences in tracer mobility into the matrix were found to be a function of their free water molecular diffusion coefficients the multiple tracer technique confirmed that matrix diffusion was a significant process that contributed to the overall physical nonequilibrium that controlled contaminant transport in the shale bedrock the experimental observations were consistent with numerical simulations of the multitracer breakthrough curves using a simple fracture flow model the simulated results also demonstrated the significance of contaminant diffusion into the bedrock matrix the multiple tracer technique and ability to monitor the fracture and matrix regimes provided the necessary experimental constraints for the accurate numerical quantification of the diffusive mass transfer process the experimental and numerical results of the tracer study were also consistent with indigenous contaminant discharge concentrations within the fracture and matrix regimes of the field site these findings suggest that the secondary source contribution of the bedrock matrix to the total off site transport of contaminants is relatively large and potentially long lived

a field example of measuring hydrodynamic dispersion in a single fracture a field example of measuring the dispersive properties of a single fracture in fractured plutonic rock is presented the experimental technique involves injecting a slug of conservative tracer into a steady groundwater flow field established between a pumping and recharging borehole and monitoring the tracer breakthrough by sampling the withdrawal water directly the breakthrough curves from two experiments were analyzed with a model which describes the flow field geometry either analytically or numerically and solves for hydrodynamic dispersion analytically a longitudinal dispersivity of 1 40 m was estimated by fitting the model to each set of field data the magnitude of the dispersion was determined to be independent of dispersive effects created by flow through the borehole instrumentation and thought to be purely hydrodynamic in nature

beyond laboratory scale prediction for channeling flows through subsurface rock fractures with heterogeneous aperture distributions revealed by laboratory evaluation the present study evaluates aperture distributions and fluid flow characteristics for variously sized laboratory scale granite fractures under confining stress as a significant result of the laboratory investigation the contact area in fracture plane was found to be virtually independent of scale by combining this characteristic with the self affine fractal nature of fracture surfaces a novel method for predicting fracture aperture distributions beyond laboratory scale is developed validity of this method is revealed through reproduction of the results of laboratory investigation and the maximum aperture fracture length relations which are reported in the literature for natural fractures the present study finally predicts conceivable scale dependencies of fluid flows through joints fractures without shear displacement and faults fractures with shear displacement both joint and fault aperture distributions are characterized by a scale independent contact area a scale dependent geometric mean and a scale independent geometric standard deviation of aperture the contact areas for joints and faults are approximately 60 and 40 changes in the geometric means of joint and fault apertures m em joint and em fault with fracture length m l are approximated by em joint 1 102 l0 1 and em fault 1 103 l0 7 whereas the geometric standard deviations of both joint and fault apertures are approximately 3 fluid flows through both joints and faults are characterized by formations of preferential flow paths i e channeling flows with scale independent flow areas of approximately 10 whereas the joint and fault permeabilities m2 kjoint and kfault are scale dependent and are approximated as kjoint 1 10 12 l0 2 and kfault 1 10 8 l1 1

an early ostrich dinosaur theropoda ornithomimosauria from the early cretaceous sao khua formation of ne thailand postcranial remains of a small theropod dinosaur including vertebrae incomplete pubes tibiae an incomplete fibula metatarsals and phalanges from the early cretaceous sao khua formation of phu wiang khon kaen province ne thailand are described as a new taxonofornithomimosaur kinnareemimus khonkaenensis gen etsp nov thisearly ostrichdino saur is characterized by a fairly advancedmetatarsus in which metatarsal iii although still visible proximally between metatarsals ii and iv in cranial view is markedly pinched more distally and becomes triangular in cross section the condition of its metatarsus shows that kinnareemimus khonkaenensis is more derived than the geologically younger primitive ornithomimosaurs harpy mimus and garudimimus but less derived than archaeornithomimus its occurrence in the early cretaceous of thailand suggests that advanced ornithomimosaurs may have originated in asia

the campania lucania southern italy earthquake of 23 november 1980 abstract we present the main seismological results of our study of the campania lucania earthquake of 23 november 1980 a complete set of far field and local data has been analysed from long period body waves data we determine the fault plane solution 1 140 1 60 2 75 2 54 a depth of 15 km and calculate a seismic moment of 6 1025 dyne cm and a source duration of 6 s from data of a local network deployed immediately after the event we determine aftershock locations they are aligned in a direction nw se that fit extremely well with the focal solution determined above we can choose as fault plane the plane striking 140 and dipping at 60 and the event is a normal event with a large component of left lateral strike slip the source area evaluated from this aftershock distribution 14 km 40 km is quite suitable for an earthquake of a seismic moment of 6 1025 dyne cm

surface rupture of the 1857 southern italian earthquake in october 1862 robert mallet published an extensive study of a large earthquake that occurred on 16 december 1857 150 km south east of naples this event is one of the most destructive ever recorded in italy although continental earthquakes of similar size are almost invariably associated with surface faulting mallet did not identify any surface rupture and subsequent workers have also failed to find surface traces using satellite images and aerial photographs as a guide we examined two prominent quaternary normal fault systems in the field flanking the val d agri and the val di diano both trend nw se and dip to the sw the distribution of damage suggests that one or both moved in 1857 on one fault segment in val d agri we found a 2 5 m high scarp whose youthfulness and height suggest it is due to the 1857 earthquake comparison of the observed slip with rates derived from geomorphic evidence suggests a recurrence time for 1857 type events of about 3000 years while the new data we provide are consistent with the event having a magnitude of ms 7 0 there are also grounds for supposing it might have been bigger

faulting geometry for the complex 1980 campania lucania earthquake from levelling data summary the destructive 1980 campania lucania earthquake was a complex event consisting of at least three subevents while the main features of the first 0 s and of the last 40 s subevents are widely accepted the second subevent 20 s is still controversial fault geometries are here determined from levelling data using a global minimization technique even if uplifts of southernmost benchmarks the most sensitive to the 20 s subevent are small new proper statistical analysis allows us to draw a few robust conclusions our results agree with previously accepted models as regards the 0 and 40 s subevents as regards the 20 s subevent previous models always assumed a northeast dipping fault while levelling data show that it could have been equivalently caused by a rupture dipping either southwest or northeast the statistical significance of the two models is about the same and strike and dip of the two faults are consistent with the two focal planes previously obtained from teleseismic data aftershock distribution seems to favour the southwest dipping fault model

a unique multitoothed ornithomimosaur dinosaur from the lower cretaceous of spain the lower cretaceous lithographic limestones from las hoyas province of cuenca spain have yielded important vertebrate fossil remains we report here a new specimen the first ornithomimosaur theropod found in europe pelecanimimus polyodon gen et sp nov has some striking elements preserved such as the hyoid sternum and integumentary impressions the fossil has revealed other unexpected features including a derived hand in an ancient ornithomimosaur and a large number of teeth over 200 with a distinctive morphology this specimen suggests an alternative evolutionary process towards the toothless condition in ornithomi mosauria which could be explained by an exaptation pelecanimimus polyodon stresses the relationship between troodontidae and ornithomimosauria

first isotopic and multidisciplinary evidence for nonmarine coelacanths and pycnodontiform fishes palaeoenvironmental implications abstract the recent coelacanth latimeria chalumnae one of the best known living fossils dwells in deep marine water fossil coelacanths have been globally related to marine environments specially after the triassic an association that has led to a general belief that they have always been marine previous reports of fossil coelacanths in continental deposits have been largely neglected prior to this report uncontested cretaceous freshwater coelacanths were unknown in turn the pycnodontiform fishes have always been considered exclusively marine apart from a few controversial exceptions here we present the first multidisciplinary evidence for nonmarine coelacanths and pycnodonts our conclusions are based upon palaeogeographic sedimentologic taphonomic and palaeoecologic criteria strongly supported by strontium 87 sr 86 sr and stable carbon and oxygen isotopic studies the coelacanth provisionally attributed to the genus holophagus and the pycnodontiforms eomesodon sp and macromesodon aff bernissartensis were unearthed at the early cretaceous locality of las hoyas cuenca spain where they grew in and inhabited a freshwater environment without marine influence fossil coelacanths and pycnodonts cannot therefore be used as unambiguous indicators of a marine environment caution is needed when using a single or a few taxa as palaeoenvironmental indicators especially fish in this sense communities are much more reliable arguments based on actualism or taxonomic uniformitarianism morphologic convergence and functional morphology are truly significant only within the framework of a sound multidisciplinary approach to the study of the palaeoenvironment

detailed study of the potentino seismic zone in the southern apennines italy abstract most relevant macroseismic and instrumental data concerning past and current seismic activity of the potentino southern italy have been collected in order to study the seismic behaviour of this area ten among the most important recent and historical earthquakes occurred in the area from 1826 to 1990 have been studied by means of macroseismic methodologies macroseismic fields for all the events indicate a general isoseismal lengthening in the direction of the apennines chain northwest southeast a rapid attenuation of intensity westward of the studied area and a strong propagation eastwards this configuration is strongly dependent on the source mechanisms of the seismic events and the geological dishomogeneities of the concerned areas as regards earthquakes which have been instrumentally recorded in the campania basilicata area from 1980 to 1991 more than 1300 accurate hypocentral locations have been computed for events with m d 2 5 using data from osservatorio vesuviano o v and istituto nazionale di geofisica i n g seismic networks special emphasis is put on the potenza may 5 1990 earthquake m s 5 4 neic national earthquake information center i vii msk which was the strongest recent event in the area and was felt in a large sector of southern italy as regards the seismic sequence following this event about 110 aftershocks with m d 1 9 have been located very close to the town of potenza northeast of it with a clustering type space distribution the occurrence of the events is strongly time concentrated in so defining a main shock aftershocks typical sequence moreover the macroseismic investigation of the main event has allowed to map out isoseismal lines bounding vii vi v and iv msk areas the isoseismals pattern shows that attenuation and amplification of intensity are observed in the same areas as for the previous events beginning from may 26 1991 an increase of seismicity initiated by an earthquake of m l 4 7 neic and i vi vii msk was observed nearly in the same area as the 1990 sequence accurate locations of 84 events with m d 1 9 have been computed however this sequence seems to have a slightly different character from the 1990 one in that events are scattered in time and seismic energy release is comparable to a swarm type seismic sequence as regards the previous sequences fault plane solutions for the highest magnitude events and for appropriate groups of events have been worked out the mechanisms indicate normal faulting motion with t axes oriented orthogonal to the apenninic chain in conclusion detailed analyses on the historical and recent seismicity of the potentino area and adjacent ones have allowed to identify at least four seismogenic zones which show activity with different features such zoning represents a contribution to the seismic hazard assessment in the southern apennines on a regional scale

evolution of the late quaternary san gregorio magno tectono karstic basin southern italy inferred from geomorphological tephrostratigraphical and palaeoecological analyses tectonic implications the pantano di san gregorio magno is a 4 7 km 2 large tectono karstic basin located in the axial belt of the southern apennines an area affected by intense seismicity the basin was formed in the middle pleistocene and is presently undissected it is filled by lacustrine sediments clays silts and pyroclastic sands passing laterally into alluvial fan deposits geomorphological investigations were integrated with tephrostratigraphical palynological and palaeoecological analyses of a 61 m thick core not reaching the bedrock the multiproxy analysis of the s gregorio magno record shows that over the last 200k yr the basin hosted a freshwater lake with an oscillating level age constraints provided by the tephrostratigraphic record allowed estimation of the sedimentation rate which varied strongly through time evolution of the basin resulted from the complex combination of tectonic subsidence karst processes and changing amounts of sedimentary inputs the latter was influenced by allogenic contributions related both to primary and reworked volcanoclastic inputs and was climate driven the overall evidence which indicates that in the long term the accumulation rate substantially counterbalanced the accommodation space created by faulting suggests that the basin evolution was also modulated by changing subsidence rates copyright 2006 john wiley sons ltd

the geometrical evolution of normal fault systems abstract the purpose of this paper is to examine the kinematic behaviour of normal fault systems and see what general conditions govern their geometrical evolution we pay particular attention to seismological and surface data from regions of present day active normal faulting as the instantaneous three dimensional geometry at the time of fault movement is better known in active regions than in areas where the faults are now static most normal faults are concave upward or listric this shape can be produced by geometric constraints either because the faults reactivate curved thrusts or because they must be curved to accommodate rotations another effect which will produce curved faults is the variation of rheology with depth brittle failure at shallow depths produces less fault rotation than does distributed creep in the lower part of the crust an important geometric feature of normal faulting is the uplift of the footwall the amount of such uplift is related not only to the elastic properties of the lithosphere but also to the throw and dip of the fault a striking feature of active normal faults is that they occur in groups in which all the faults dip in the same direction this behaviour arises because the faults cannot intersect if they do one must cease to be active the rotation which such fault systems produce reduces the dip of the faults until a new steeply dipping fault is formed once a new fault cuts pre existing faults the earlier faults become locked and a new set of faults must propagate rapidly across the whole region involved many of these geometric constraints also apply to thrust faulting

new paleoseismic data from the irpinia fault a different seismogenic perspective for southern apennines italy abstract the irpinia fault i e mount marzano fault system mmfs was responsible for the devastating 1980 earthquake mw 6 9 that caused the longest surface faulting ever observed in italy 30 km early paleoseismological studies have revealed a 2 kyr recurrence time for 1980 like characteristic earthquakes on this fault system during the holocene however this appears to clash with both the catastrophic historical seismicity and high gps derived strain rate of the area to explain this apparent discrepancy we investigated the mmfs through a multidisciplinary approach first on the basis of recent archives and archaeological research we reassessed the historical seismicity of the area analysing the highest intensity distribution of the major earthquakes of the upper ofanto valley with respect to the mmfs hanging wall then we carried out a step by step survey along the entire 43 km long fault system through both high precision topographic levelling along the compound fault scarp and geostructural analyses finally we excavated trenches and pits across different fault segments to explore the recent paleoseismological history of the structure based on the combined results that we have obtained we propose a different point of view concerning the seismogenic behaviour of the mmfs from the holocene to the present at the end fault parameters have been compared with those of all the apennines active faults and cross checked with the newest gps results in peninsular italy providing some relevant observation of the relationships between seismogenesis and geodetic deformation

from aperture characterization to hydraulic properties of fractures abstract a methodology is suggested to measure the aperture and estimate the hydraulic properties of desiccation and tectonic fractures in heterogeneous soils the aperture of desiccation fractures is quantified by the fluctuating distance between two opposite faces and is modelled as a network of parallel plates of variable opening the aperture of tectonic fractures is modeled as a 2 dimensional network of elliptical channels with parameters the major and minor axis lengths scanning electron microscope sem images of the 2 dimensional cross sections of resin impregnated fractures are employed to estimate the statistics of the fracture aperture parameters in both cases this information is coupled with effective medium approximation for the calculation of the mean hydraulic fracture aperture which allows us to estimate approximately the permeability of the fracture networks over the various zones of the soil the estimated values of permeability are comparable to corresponding ones measured with gas permeation tests on the field invasion percolation models are used to simulate the quasi static and pressure controlled immiscible displacement of oil water drainage in single fractures and estimate the relevant capillary pressure and relative permeability curves which are similar to corresponding ones resulting from the inverse modelling of two phase flow experiments in planar glass etched networks of elliptical pores

use of long period surface waves for rapid determination of earthquake source parameters 2 preliminary determination of source mechanisms of large earthquakes ms 6 5 in 1980 an inversion method for fast retrieval of earthquake source parameters developed earlier has been applied to 28 large m s 6 5 shallow earthquakes which occurred in 1980 rayleigh waves recorded by the ida international deployment of accelerographs network were used for the analysis for very shallow events the inversion is ill conditioned and two of the moment tensor elements m zx and m zy are unresolvable of the 28 events a solution is obtained for 25 with the constraints m zx m zy 0 although these constraints limit the solution to be either vertical strike slip or 45 dip slip the method provides a useful first approximation to the mechanism solution for deeper events all of the elements of the moment tensor can be determined after the seismograms have been retrieved the solution can be obtained in 10 min for most events the method would be adequate for preliminary cataloging purposes

a large scale flow and tracer experiment in granite 2 results and interpretation water and tracer flow has been monitored in a specially excavated drift in the stripa mine several new experimental techniques and equipment were developed and used the whole ceiling and the upper part of the walls were covered with 375 individual plastic sheets where the water flow into the drift could be collected eleven different tracers were injected at distances between 11 and 50 m from the ceiling of the drift the flow rate and tracer monitoring was kept up for more than 2 years the tracer breakthrough curves and flow rate distributions were used to study the flow paths velocities hydraulic conductivities dispersivities and channeling effects in the rock in a companion paper the experimental design and performed experiments are described the present paper describes the interpretation of flow and tracer movement in the rock outside the drift the tracer movement was measured by the more than 160 individual tracer curves the tracer experiments have permitted the flow porosity and dispersion to be studied the possible effects of channeling and the diffusion of tracers into stagnant waters in the rock matrix and in stagnant waters in the fractures have also been addressed

assessing the validity of the channel model of fracture aperture under field conditions in recent investigations of fluid and solute movement in discrete fractures spatial heterogeneity of the fracture aperture has been conceptualized as a series of noninterconnecting constant aperture flow paths or channels two methods of estimating the distribution of the aperture sizes are presented using information from a single hole pumping test and a radially converging tracer test the first method uses the transmissivity of the fracture and mean arrival time of the tracer while the second method uses the mean and variance of the solute arrival time if the fracture can be conceptualized as a series of nonintersecting flow paths of constant aperture the two methods should yield identical estimates for the parameters of the distribution the validity of the channel model can be assessed by comparing the parameters of the distribution that are estimated by the two methods this technique was demonstrated using hydraulic and tracer tests conducted in a discrete areally extensive horizontal fracture in the silurian dolomite in the northeastern illinois a lognormal and a truncated gamma distribution were used to describe the distribution of constant aperture flow paths the lognormal distribution could not reproduce the abrupt rising limb and maximum rate of mass arrival that characterized the tracer tests the gamma distribution more accurately predicted the shape of the breakthrough curves however the two methods of estimating the parameters of the distribution provided significantly different estimates of the variances of the aperture sizes the mean aperture as estimated by the two methods was similar the difference in the variance of the aperture as estimated by the two methods indicates that alternative conceptual models of aperture heterogeneity are required to more accurately describe both fluid and solute movement in this field situation

unsaturated flow and transport through a fault embedded in fractured welded tuff 1 to evaluate the importance of matrix diffusion as a mechanism for retarding radionuclide transport in the vicinity of a fault located in unsaturated fractured rock we carried out an in situ field experiment in the exploratory studies facility at yucca mountain nevada this experiment involved the release of 82 000 l of water over a period of 17 months directly into a near vertical fault under both constant positive head at 0 04 m and decreasing fluxes a mix of conservative tracers pentafluorobenzoic acid pfba and bromide applied in the form of lithium bromide was released along the fault over a period of 9 days 7 months after the start of water release along the fault as water was released into the fault seepage rates were monitored in a large cavity excavated below the test bed after the release of tracers seepage water was continuously collected from three locations and analyzed for the injected tracers observations of bromide concentrations in seepage water during the early stages of the experiment and bromide and pfba concentrations in the seepage water indicate the significant effects of matrix diffusion on transport through a fault embedded in fractured welded rock

tracer transport in fractured crystalline rock evidence of nondiffusive breakthrough tailing extended tailing of tracer breakthrough is often observed in pulse injection tracer tests conducted in fractured geologic media this behavior has been attributed to diffusive exchange of tracer between mobile fluids traveling through channels in fractures and relatively stagnant fluid between fluid channels along fracture walls or within the bulk matrix we present a field example where tracer breakthrough tailing apparently results from nondiffusive transport tracer tests were conducted in a fractured crystalline rock using both a convergent and weak dipole injection and pumping scheme deuterated water bromide and pentafluorobenzoic acid were selected as tracers for their wide range in molecular diffusivity the late time behavior of the normalized breakthrough curves were consistent for all tracers even when the pumping rate was changed the lack of separation between tracers of varying diffusivity indicates that strong breakthrough tailing in fractured geologic media may be caused by advective transport processes this finding has implications for the interpretation of tracer tests designed to measure matrix diffusion in situ and the prediction of contaminant transport in fractured rock

euclidean and fractal models for the description of rock surface roughness accurate description of the topography of rock surfaces is essential because surface roughness affects frictional strength the flow of fluids in joints and fractures the seismic behavior of faults and the formation of gouge and breccia in fault zones real rock surfaces can be described using self similar and self affine fractal models of surface roughness if a surface is self similar a small portion of the surface when magnified isotropically will appear statistically identical to the entire surface if a surface is self affine a magnified portion of the surface will only appear statistically identical to the entire surface if different magnifications are used for the directions parallel and perpendicular to the surface at least two parameters are required to describe a fractal model one parameter typically describes how roughness changes with scale while the other specifies the variance or surface slope at a reference scale the divider method and the spectral method are in common use to determine the best fit fractal model from surface profile data power spectra from self similar surfaces have slopes of 3 on log log plots of power spectral density versus spatial frequency while spectra from self affine surfaces have slopes other than 3 power spectra can be interpreted with greater facility if dimensionless amplitude to wavelength ratios are contoured on plots of power spectral density versus frequency the topography of many natural rock surfaces including both fractures and faults is approximately self similar within the 6 5 order of magnitude wide wavelength band of 10 m to 40 m within smaller wavelength bands natural rock surfaces may exhibit self affine behavior

the southern italy earthquake of 23 november 1980 an unusual pattern of faulting abstract a complex rupture history for the 23 november 1980 magnitude 6 9 italian earthquake resulted in an unusual pattern of two high angle subperpendicular normal faults forming the corner of a down dropped crustal block evidence for this interpretation is from aftershocks the pattern of strong ground motion focal mechanism of the mainshock and two critically placed leveling profiles quantitative modeling of leveling profiles using smoothly varying dislocation segments provides confirmation of the fault pattern and specific verification of the existence of a secondary fault which is suborthogonal to the primary fault rupture began on the nw trending main fault with downward motion of the northeast block about 40 sec after initial motion began rupture initiated on an orthogonal ne trending subsidiary fault propagating away from the main fault this fault pattern is consistent with tectonic extension in a northeasterly direction

radionuclide transport in fast channels in crystalline rock recent field investigations in crystalline rock give strong indications that water flows in largely isolated channels in fissured rock the present paper sets out to investigate radionuclide transport in such channels including diffusion into the rock matrix it is shown that the uptake from a cylindrical hole in a matrix is much more effective per unit contact area than a flat surface semi infinite solid comparison of diffusion from cylindrical and slit formed channels shows that the differences in interfacial flux are minor a slit formed channel may therefore be approximated by a cylindrical one diffusional transport in the matrix is then treated as one dimensional instead of two dimensional which gives a considerable numerical simplification a simple estimate of the penetration depth into the cylindrical region i e the location of the diffusional front is proposed by using the integrated finite difference method a number of radionuclide transport calculations are performed for the case of flow and dispersion in a cylindrical channel coupled to diffusion and sorption in the matrix

late quaternary faulting within the southern apennines seismic belt new data from mt marzano area southern italy abstract an integrated geomorphological and geophysical investigation was performed in order to reconstruct the pliocene quaternary geomorphologic evolution and recent tectonics of mt marzano massif southern apennines italy the study area belongs to a region of high seismic energy release the last event being the strong ms 6 9 1980 irpinia earthquake most of the main faults of the area ceased their activity before development of the late pliocene age palaeosurfaces widely spread over the massif beginning in the lower part of the middle pleistocene strong extensional tectonics took place in the southern portion of the massif wnw trending faults created the buccino and s gregorio magno depressions which underwent subsidence until the holocene according to abundant morphostructural evidence during the late quaternary the n150 trending mt valva mt carpineta fault and the n110 100 trending mt ogna fault previously sealed by pliocene palaeosurfaces also were re activated morphostructural data were integrated with a high resolution seismic survey across the piano di pecore basin which is dammed by a fault that slipped 70 cm during the 1980 earthquake this fault produced no more than 50 60 m of throw during quaternary times most probably starting from 100 to 150 kyr bp

the rupture process of the 1980 irpinia italy earthquake from the inversion of strong motion waveforms abstract the distribution of slip and the behaviour of rupture propagation during the 23rd november 1980 irpinia earthquake ms 6 9 was investigated by analysing strong motion accelerograms the rupture was assumed to develop on a two dimensional purely normal fault whose geometry was constrained by geologic and geodetic data and by the aftershock space distribution theoretical seismograms have been computed using the isochron approach with a spatially variable slip intensity the asymptotic ray theory is used to evaluate the far field green functions the rupture model was updated following a trial and error approach the fit of observed waveforms with synthetic seismograms allowed several peculiarities in the rupture history to be pointed out the source model resulting from the solution of the forward waveform modelling was then used as starting model for the inversion of ground velocities therefore we performed a linearized inversion for slip velocity and rupture times on the fault by iteratively perturbing the assumed starting model the inverse problem is solved by means of a tomographic back projection technique the inferred source model shows a bilateral rupture which does not propagate uniformly away from the hypocentre the rupture velocity and the slip distribution on the fault plane are rather variable the solution confirms the shallow dislocation gap in the central part of the fault suggested by the behaviour of the surface rupture the results indicate that the rupture propagated northwestward along a further fault fragment for which no surface evidence is observed the aftershocks occurred mostly inside of or near to the edges of the source areas of maximum co seismic slip

moment and duration of shallow earthquakes from love wave modelling for regional distances abstract love waves from five earthquakes in southwest germany italy yugoslavia greece and algeria as recorded at the broadband grafenberg array in eastern bavaria are modelled in detail using an extended reflectivity method the focal mechanisms are taken from the literature or determined from long period wwnss data the theoretical double couple moment function used for modelling increases smoothly during the risetime t from zero to the seismic moment m0 t and m0 are determined by matching the observed and theoretical love wave seismograms in the long period wwnss frequency band t is approximately equal to the rupture duration values from 1 4 to 20 s are found seismic moments generally agree within a factor of about two with those found by other authors from larger data sets the earthquakes in southwest germany and greece were simple events and can be modelled very well by one double couple in the case of the other earthquakes the theoretical love wave seismograms are too short for these earthquakes there is some independent evidence for a multiple event nature this evidence is condensed into source models consisting of two or three double couples representing separate and complete sub earthquakes which then explain the observations quite well in the case of the algerian earthquake the long love wave duration may also be due to complications in structure along the wavepath across the mediterranean and the alps the present results show that accurate love wave modelling for a single station at regional distance from an epicentre is a reliable method for estimation of seismic moment and rupture duration use of a digitally recording station with large dynamic range allows events over a large magnitude interval to be studied the grafenberg array is well suited for such an investigation of european and north african earthquakes

block rotation in western turkey 1 observational evidence western turkey is a region of rapid continental extension where extension rate increasing westward causes counterclockwise vertical vorticity and hence counterclockwise rotation around vertical axes on a regional scale field observations and seismicity of the past century are used to deduce positions and slip senses of major active oblique normal faults in this region which take up extension in the upper crustal brittle layer and allow fault bounded blocks to rotate around vertical axes the principal active normal faults in western turkey strike roughly east west near the aegean coast turning gradually toward westnorthwest eastsoutheast strike across 200 km distance inland to the east slip vector azimuths indicate typical extension direction on these faults is s18 8w they truncate a second set of faults with smaller displacement and roughly orthogonal strike and slip vector azimuth as well as subdividing the brittle layer into blocks that show little internal deformation some major oblique normal faults subdivide it into domains that show different neogene rotation around vertical axes some domains contain sets of major active oblique normal faults that bound blocks that are elongated angular and shaped like tilted dominoes these faults take up extension and can also take up rotation around vertical axes provided they and the blocks between them rotate around vertical axes at the same rate where adequate paleomagnetic observations are available they indicate these domains have rotated counterclockwise as expected by up to 40 roughly equal to the change in strike of the principal set of active faults between the aegean coast and the eastern edge of the actively extending zone however evidence is scarce for the right lateral strike slip expected in some kinematic models on a set of oblique normal faults that takes up extension and counterclockwise rotation instead each fault appears to have the component of strike slip necessary to enable it given its local strike to slip in ue direction in which the region is extending two domains that have rotated clockwise are approximately circular in plan view with diameter 90 km and are bounded by faults with variable orientation each comprises a single block with no internal major active faults

source complexity of the 1980 southern italian earthquake from the analysis of strong motion s wave polarization strong motion records from 23 november 1980 earthquake in irpinia basilicata southern italy recorded less than 59 km to the source show strong s wave phases coherent up to 10 hz at more distant stations the signal is only coherent up to 5 hz even when recordings contain signal up to 10 hz hodogram plots of the coherent signal in the 5 to 10 hz range show lissajous figures of sh and sv waves radiated by the nearest point with strong seismic radiation by the terminations of the rupture or by other relatively compact features the largest acceleration recorded at the sturno station is due to high frequency pulses radiated by a source south of the station and 25 km from the epicenter hodogram plots of low frequencies show polarizations due to the propagation of the large scale rupture along the fault lissajous figures help to discriminate p and s arrivals and reveal their direction of propagation on the basis of this kind of analysis it is confirmed that the 1980 irpinia basilicata earthquake ml 6 5 was composed of three main sub events at 0 sec 19 sec and 39 sec in relative time the first and second events broke the same structure striking nw there is also evidence of bilateral propagation the third event broke a second smaller structure also striking nw and placed very close to the alignment of the previous ones

the analysis of tracer experiments conducted in divergent radial flow fields analytical models are developed to interpret tracer experiments conducted in divergent flow fields the models account for the mixing of tracer in both the source and observation wells and for the diffusion of tracer into adjacent aquitards a solution for the particular case of an observation well of infinitesimally small volume is also presented solutions are derived for both resident and flux concentrations and for macroscopically discontinuous conditions at both the inlet and outlet boundaries the solutions for resident and flux concentration are identical when the mixing volume in the observation well is of finite volume two tracer experiments were conducted in a horizontally fractured shale to demonstrate the application of the new analytical models experiments were conducted with observation wells of finite volume and using a new sampling packer which eliminates the volume of the observation well the results show that for experiments conducted in fractured media the analytical model developed in this paper provides an improved fit to the shape of the concentration curve relative to models which do not account for mixing in the source and observation wells alternatively by modifying the field method such that the volume of the observation well is eliminated using the sampling packer either conventional models or the new model for concentration in the formation will provide equally suitable fits to the concentration data

an articulated hindlimb of a basal iguanodont dinosauria ornithopoda from the early cretaceous las hoyas lagerstatte spain an isolated fully articulated hindlimb of a basal iguanodont from the spanish las hoyas lagerstatte is described it probably belonged to a juvenile or subadult individual despite some slight differences anatomical features as well as the late barremian age of this specimen would suggest that it belongs to mantellisaurus atherfieldensis the exquisite preservation of this specimen provides information on the foot anatomy of basal iguanodonts this is the first report of a non theropod dinosaur from las hoyas from a palaeoecological point of view this discovery indicates that potential prey of the carcharodontosaurian theropod concavenator were present at las hoyas thus complementing our knowledge of the trophic structure of this early cretaceous palaeocommunity

cretaceous tetrapod fossil record sampling and faunal turnover implications for biogeography and the rise of modern clades we use newly compiled data on global occurrences of cretaceous lepidosaurs mammals and crocodylomorphs and existing data on dinosaurs to investigate faunal turnover and fossil record heterogeneity statistically significant relationships between many clade specific fossil record sampling proxies within major continental areas e g european mammal bearing formations suggest that temporal patterns of fossil record sampling intensity of the most abundant tetrapod clades are similar to each other with a few exceptions that might reflect clade specific facies preferences or differences in worker effort especially in poorly sampled regions such as gondwana however the absence of strong statistical relationships between tetrapod sampling proxies from different continental areas suggests that there is no unified global sampling signal for terrestrial tetrapods the cretaceous witnessed substantial faunal turnover and the rise of many advanced clades that today dominate terrestrial faunas despite strong spatiotemporal heterogeneity in sampling of the cretaceous tetrapod record it is clear that this transition occurred in a spatiotemporally staggered fashion thus it cannot be attributed to a temporally localised early late cretaceous cenomanian turonian extinction event many advanced clades including eutherian mammals iguanian and gekkotan squamates and the main cryptodiran turtle crown clades first appeared or first attained high fossil diversities in asia however relatively poor sampling and dating of middle cretaceous terrestrial deposits means that hypotheses of asian rather than laurasian diversifications remain tentative differences between gondwanan and laurasian faunas became progressively greater during the cretaceous and although many gondwanan clades survived the end cretaceous extinction event these only survive to the present as relictual populations with narrow geographic ranges e g monotremes and rhynchocephalians

different styles of deformation in the calabrian arc southern italy implications for a seismotectonic zoning abstract the most recent seismic profiles in southern italy show the existence of a sudden thinning of the crust at the boundary between the chain and the tyrrhenian margin the abrupt change in thickness can be followed along a zone which has the same geometry in plan as the calabrian arc by considering these data and the gravimetric anomalies it is possible to associate this crustal anomaly with a deep seated shear zone which determines a crustal shortening of about 40 60 km which can only be a consequence of post tortonian tectonics the surface equivalents of the deep seated shear zone can be recognized from north to south in the alignment of the intra apenninic basins vallo di diano san arcangelo potenza in the crati mesima graben and in the mount kumeta alcantara fault zone the distribution of the seismicity and its connection with the surface structures shows that the largest earthquakes occur along the deep shear zone in particular shocks with the highest magnitude and the longest recurrence intervals are located in those areas where the deep shear zone is at an angle of about 90 with the direction of maximum shortening crati mesima graben the fault zones nearly parallel to the regional compression axis e g mount kumeta alcantara fault zone are characterized by earthquakes of lower magnitude taking into account the neotectonic evolution of the regional structures as well as the orientation of the stress field and its connection with the deep seated shear zone it is possible to distinguish the following seismotectonic zones upper crati mesima graben transverse throughs mount pollino mount raparo fault zone external ionian area san arcangelo basin zone of the external flysch sicani mountains mount kumeta alcantara fault zone caltanissetta basin and iblean plateau bradanic trough murge ridge the definition of the geometry of the shear zone at depth is one of the most important but still unresolved problems

dispersion in tracer flow in fractured geothermal systems interpretation of tracer tests is commonly based on the analysis of flow through a porous medium in geothermal reservoirs however the principal permeability arises from fractures and a porous medium approach is not applicable the dispersion of tracer material flowing in a fracture is shown to be dominated by molecular diffusion across the fracture a mechanism known as taylor dispersion for typical values of reservoir parameters this transverse diffusion will obliterate any transverse tracer concentration gradients caused by the velocity profile across the fracture the effective dispersivity is found to be a function of fracture aperture mean flow velocity and molecular diffusivity and is orders of magnitude greater than for porous medium flow typically peclet numbers are anticipated to lie between orders 1 and 100 and field results confirm this range

new constraints shed light on strike slip faulting beneath the southern apennines italy the 21 august 1962 irpinia multiple earthquake abstract on 21 august 1962 an earthquake sequence set off near the city of benevento in italy s southern apennines three earthquakes the largest having mw 6 1 struck virtually the same area in less than 40 min at 18 09 18 19 and 18 44 utc respectively several historical earthquakes hit this region and its seismic hazard is accordingly among the highest countrywide although poorly understood in the past the seismotectonics of this region can be revealed by the 1962 sequence being the only significant earthquake in the area for which modern seismograms are available we determine location magnitude and nodal planes of the first event 18 09 utc of the sequence the focal mechanism exhibits dominant strike slip rupture along a north dipping e w striking plane or along a west dipping n s striking plane either of these solutions is significantly different from the kinematics of the typical large earthquakes occurring along the crest of the southern apennines such as the 23 november 1980 irpinia earthquake mw 6 9 caused by predominant normal faulting along nw se striking planes the epicentre of the 21 august 1962 18 09 event is located immediately east of the chain axis near one of the three north dipping e w striking oblique slip sources thought to have caused one of the three main events of the december 1456 sequence io xi mcs the most destructive events in the southern apennines known to date we maintain that the 21 august 1962 18 09 earthquake occurred along the e w striking fault system responsible for the southernmost event of the 1456 sequence and for two smaller but instrumentally documented events that occurred on 6 may 1971 mw 5 0 and 27 september 2012 mw 4 6 further suggesting that normal faulting is not the dominant tectonic style in this portion of the italian peninsula

the tectonic geomorphology of bedrock scarps on active normal faults in the italian apennines mapped using combined ground penetrating radar and terrestrial laser scanning using combined datasets from ground penetrating radar gpr and terrestrial laser scanning tls we document the variety of tectono geomorphic features that contribute to the morphology of bedrock scarps associated with active extensional faulting in central italy measurement of faulted offsets across such scarps can provide important fault slip rate data relevant to seismic hazard analysis if ages can be established for offset features however interpretation of these offsets is challenging when geomorphic processes as well as fault slip contribute to exhumation of the bedrock during scarp development through the integration of surface tls and subsurface gpr datasets we show that the surface expression of three bedrock scarps results from the interaction between footwall incision hangingwall sedimentation channel incision and landsliding as well as fault slip and fault linkage we further illustrate how these processes can be differentiated to identify locations suitable for determining fault slip rates the identification of such features has important implications for our understanding of the relationship between bedrock faulting and geomorphic processes in turn contributing to improved assessment of fault slip rates in the central apennines the use of combined gpr and tls datasets here has shown that the tectono geomorphic features of the studied scarps vary greatly over short distances and we emphasise the need for detailed scarp analysis to elucidate the processes responsible for bedrock exhumation before estimating the rates of fault slip over the timescale of scarp formation

impact of coating and weathering on the properties of chalk fracture surfaces the surface topography of a natural fracture intersecting a chalk formation was mapped using a high resolution laser scanning device and its roughness was evaluated using five different criteria two coated and two uncoated slices of the natural fracture surface were encased in flow cells and exposed to short 24 and 8 hours interactions with percolating synthetic rainwater and industrial wastewater followed by long drying periods weeks these flow experiments simulated the intermittent infiltration of surface runoff and industrial effluents typical of the study area and resulted in erosion of the fracture surfaces and modification of their roughness the temporal variations in surface roughness were evaluated using three commonly used criteria standard deviation from mean heights differences between maximum and minimum heights and the root mean square roughness and two newly developed measures namely the slopes on the surfaces and a calculated roughness related ratio rrr the mean slope maps and rrr calculations were found to be good criteria for evaluating surface topography and its uniformity across the fracture surface the coated surfaces were significantly rougher had greater relief more heterogeneous topography and a larger surface area than the uncoated surfaces the results suggest that coating and fast weathering caused by intermittent flow events significantly change roughness surface area relief and the heterogeneity of a fracture surface these in turn may affect the spatial distribution of flow paths across that fracture surface consequently when exploring the properties of fracture surfaces and fracture flow the impact of surface skin and variations of the surface properties over short timescales should be taken into account

new information on cretaceous troodontids dinosauria theropoda from the people s republic of china troodontid specimens were recovered from three localities in china by the sino canadian expeditions between 1987 and 1990 these include a lower cretaceous form sinornithoides youngi which is the most complete troodontid skeleton ever found isolated bones from the iren dabasu formation turonian and partial skeletons of saurornithoides mongoliensis from djadokhta equivalent beds campanian these and other specimens recently described from north america allow a better assessment of the phylogenetic position of troodontids than has been possible before although troodontids have autapomorphies that eliminate them from consideration as bird ancestors they are nevertheless one of the closest avian outgroups within the theropoda

surface faulting in the southern italian campania basilicata earthquake of 23 november 1980 the campania basilicata earthquake of 23 november 1980 was the largest ms 6 9 and most destructive earthquake that has occurred in this region of southern italy for over 100 years killing more than 3 000 people the consensus among seismologists geologists and earthquake engineers who have studied1 10 this event is in keeping with previous italian earthquakes that it did not produce faulting at the surface this has led to the establishment of a number of models2 3 11 13 requiring an unusual tectonic setting for the southern apennines however on a recent visit to the epicentral region of the earthquake may 1984 we discovered more than 10 km of surface faulting that is consistent with focal mechanisms for this event based on first motion polarities2 4 5 12 and long period waveform studies14 16 which show that it involved normal faulting with one nodal plane dipping at 60 towards the north east our observations of this the first well documented earthquake fault break to be reported in italy suggest that the deformation associated with earthquakes in the southern apennines takes place in the upper 10 15 km of the earth s crust on steep planar normal faults which break the surface as is widely observed in other areas of active extension outside italy

active oblique extension in the central apennines italy evidence from the fucino region the fucino basin is a flat quaternary depression within the central apennines it is surrounded by active normal faults with small oblique slip components surface faulting was observed along the east side of the basin during the ms 7 0 avezzano earthquake of 1915 in order to understand the kinematics of recent strain better and to assess the seismic hazard of this region we carried out a detailed geomorphic and structural study of the faults around the basin fault scarp heights were accurately measured with total station profiles and vertical slip rates were estimated assuming slope offsets to post date the end of periglacial abrasion 14 4 kyr bp to the north the most prominent fault the magnola fault appears to have an average postglacial throw rate of 0 7 0 3 mm yr 1 and together with the velino fault to be capable of generating earthquakes of maximum magnitudes of 6 9 7 3 with recurrence intervals of 1000 3000 yr east of the basin the serrone parasano and ventrino faults form a right stepping horsetail of the giovenco fault current vertical slip rates on the three former faults appear to be between 0 5 and 1 4 0 5 and 1 0 and 0 3 and 1 1 mm yr 1 respectively infrequent maximum magnitude earthquakes on them may also exceed 7 particularly in the case of coupled rupture with loosely constrained recurrence intervals up to several thousand years the right lateral slip components implied by the most recent slickensides and by geomorphic offsets on the nw se trending normal faults of the area suggest that the blocks they bound rotate counterclockwise consistent with oblique left slip on the nnw sse trending giovenco and ovindoli faults to the east sinistral shear parallel to the latter faults the maximum relief across the magnola fault and the postglacial slope offsets measured suggest that the extension rate across the central apennines might be of the order of 6 3 mm yr 1 in a n20 10 e direction more northerly than hitherto inferred

present day kinematics of the plate boundary zone between africa and europe from the azores to the aegean anticlockwise rotation of africa relative to europe around an euler pole in the eastern atlantic causes plate convergence in the central mediterranean towards n20 w at rate considered a priori to be 5 10 mm yr 1 however previous summaries of the present day deformation sense in the central mediterranean are inconsistent with observations in southern italy recent investigations of italy and adjacent parts of north africa enable local deformation sense observed to be reconciled with sense predicted from relative plate motions suggested angular velocity of the african plate relative to europe is 0 07 myr 1 around a pole near 21 n 21 w this predicts 2 6 mm yr 1 maximum extension rate towards n64 e near the azores consistent with the minimum local accretion of new oceanic crust in the past few millions of years and 4 3 mm yr 1 plate convergence towards n20 w in the central mediterranean at 13 e further east the northern margin of the african plate can be regarded as the gargano seismic zone in the central adriatic sea the northern adriatic sea is a microplate rotating anticlockwise relative to europe at 0 3 myr 1 around a pole in northwestern italy causing northeastward shortening in yugoslavia and up to 4 mm yr 1 extension in central and northern italy the african plate is deforming internally in tunisia and northern libya extending obliquely in direction e10 s at rate up to 5 5 mm yr 1 the resultant velocity relative to europe in the ionian and southern adriatic seas 5 mm yr 1 towards n50 e explains the observed relative velocity across southern italy kinematic consistency requires present day shortening rate east of calabria associated with subduction on the tyrrhenian sea benioff zone and tyrrhenian sea extension rate to be both zero or equal to within 1 mm yr 1

high resolution non destructive measurement and characterization of fracture apertures abstract we measure at high resolution the fracture aperture of several consolidated materials and statistically characterize the aperture distribution for future studies on single and multiphase flow and transport through fractured porous media the images of the real fractures in granite and sandstone rocks are obtained with a computer aided tomography cat x ray scanner the minimum pixel size is 0 27 0 27 mm but fractures as small as 35 m can be accurately measured using a calibration standard for the variation in ct number due to the missing rock mass in a given pixel the distribution of fracture apertures is best described by a lognormal function this was also corroborated by comparing the theoretical to actual ratio of geometric mean to arithmetic mean apertures the mechanical roughness of the fractures ranged from 0 17 to 1 5 the variability in fracture aperture displayed only short range structure with correlation lengths of 0 8 to 7 mm at maximum which is at most one tenth of the minimum dimension width of the fracture plane fracture aperture distribution is rather heterogeneous potential flow channels can be deduced from the fracture aperture distribution

paleoseismicity of the ovindoli pezza fault central apennines italy a history including a large previously unrecorded earthquake in the middle ages 860 1300 a d geomorphic and trenching investigations along the ovindoli pezza fault show that this normal fault is one of the major seismogenic faults in the central apennines we found clear geological evidence for three holocene surface faulting earthquakes on this fault the most recent earthquake occurred in the middle ages between 860 and 1300 a d the penultimate occurred about 1900 b c or shortly after and the oldest probably occurred between 3300 and 5000 b c although the most recent surface faulting earthquake occurred during historical time no evidence for it have been found in the historical record slip per event ranges between 2 and 3 m and the length of the rupture is at least 12 20 km suggesting m 6 5 7 0 for the paleoearthquakes the dip slip rate determined from trenching is 0 7 1 2 mm yr and is consistent with the long term slip rate of 0 9 2 5 mm yr lower values preferred obtained from displaced geomorphic features trench data combined with long term slip rate estimates suggest the recurrence interval is longer than a millennium and possibly as long as 3300 years the time elapsed since the most recent earthquake is 700 1130 years the seismic behavior of the ovindoli pezza fault is consistent with other well known seismogenic faults of the central and southern apennines the lack of mention or mislocation of the most recent event on the ovindoli pezza fault in the historical record of the past two millennia should be attributed mainly to the unsettled cultural and social conditions and poor economic state that characterized the middle ages especially in thinly populated regions such as the central apennines this example highlights an intrinsic limit of the historical data and raises the possibility that other regions considered seismically quiet on the basis of a long historical record may in reality have had large earthquakes that were not recorded

late quaternary tectonics of the vallo di diano basin southern apennines italy italian ministry of university and research project firb research and development of new technologies for protection and defence of territory from natural risks w p c3 crustal imaging in italy

abruzzo italy earthquakes of april 2009 heterogeneous fault slip models and stress transfer from accurate inversion of envisat insar data abstract the seismic sequence that occurred in the abruzzo apennines near l aquila italy in april 2009 caused extensive damage and a large number of casualties more than 300 the earthquake struck an area in the italian apennines chain where several faults belonging to adjacent seismotectonic domains create a complex tectonic regime resulting from the interaction among regional stress buildup local stress changes caused by individual earthquakes and viscous elastic stress relaxation understanding such complex interaction in the apennines can lead to a large step forward in the seismic risk mitigation in italy the abruzzo earthquake has been very well recorded by interferometric synthetic aperture radar insar data much better than the first italian earthquake ever recorded by satellites namely the 1997 umbria marche earthquake envisat environmental satellite data for the abruzzo earthquake are in fact very clear and allow an accurate reconstruction of the faulting mechanism we present here an accurate inversion of vertical deformation data obtained by envisat images aimed to give a detailed reconstruction of the fault geometry and slip distribution the resulting fault models are then used to compute by a suitable theoretical model based on the elastic dislocation theory the stress changes induced on the neighboring faults the correlation of the subsequent mainshocks and aftershocks of the abruzzo sequence with the volumes undergoing increasing coulomb stress clearly evidence the triggering effect of coseismic stress changes on further seismicity moreover this analysis put in evidence which seismotectonic domains have been more heavily charged by stress released by the abruzzo mainshocks the most important faults significantly charged by the abruzzo sequence belong to the sulmona and avezzano tectonic domains taking into account the average regional stress buildup in the area the positive coulomb stress changes caused by this earthquake can be seen as anticipating the next earthquakes in the neighboring domains of 15 20 yr