quantitative subsidence analysis and forward modelling of the vienna and danube basins thin skinned versus thick skinned extension abstract we present the results of a quantitative study of the tectonic evolution of the vienna and danube basins by comparing tectonic subsidence histories derived from backstripping of more than 90 wells from slovakia hungary and austria with the predictions from forward tectonic modelling subsidence analysis and forward modelling using a modified non uniform extension model address the tectonic relations between different depocentres and the nature of tectonic subsidence we derived stretching values for the vienna basin between 1 04 and 1 30 for the crustal extension and between 1 00 in the northern part and 1 60 southern part for the lithospheric extension the danube basin is characterized by crustal extension values between 1 09 and 1 30 and lithospheric extension values between 1 00 northern part and 1 60 southern part the vienna basin shows a trend from thin skinned extension in the northwestern part to whole lithospheric extension in the central southern part the subsidence history of the northwestern part of the danube basin also reflects a thin skinned extensional basin formation mechanism the central and southern parts of the danube basin show an important component of lithospheric extension the basin evolution is strongly influenced by the rotating stress field through miocene times expressed in different phases of fault reactivation that are observed in the subsidence history

shear in the lower crust during extension not so pure and simple abstract as lower crustal reflectivity appears to be related to extension it is sensible to consider the role of the lower crust in the extension of the lithosphere and in particular the way the lower crust deforms the occurrence of transparent zones wrapped around by reflective bands can be interpreted as low strain regions enclosed within anastomosing shear zones suggesting that deformation in the lower crust is by the relative movements of low strain lozenges along acoustically reflective high strain zones although this deformation can easily accommodate bulk pure shear it can also develop during bulk simple shear a component of subhorizontal simple shear within the lower crust is necessary if deformation in the mantle is localised into shear zones with the geometry and distribution imaged on birps profiles the lower crust may be the critical link in the lithosphere transferring deformation between the relatively strong upper crust and upper mantle and being strongly sheared in the process the form of this shearing is a direct consequence of the way the entire lithosphere extends

geological and geotechnical constraints for urban planning and natural environment protection a case study from mekelle city northern ethiopia the study was conducted in the rapidly expanding city of mekelle located in the northern part of ethiopia east africa an integrated approach including geomorphological geological and engineering geological geotechnical and hydrogeological methods were used to characterize the natural urban environment to be used as a baseline for protection and rational planning of development conventional field observation test pits and drilled boreholes were used to collect soil rock and water samples and standard laboratory procedures were applied the results revealed that the main geologic constraints to sustainable development of the city are active erosion instability of slopes flood hazard cyclic alternating hard and weak rock layers high swelling shrinkage soils shallow and unconfined groundwater with variable composition and high susceptibility to corrosion and pollution it is recommended to avoid development and expansion of the city in areas of steep land forms at the foot of steep slopes and in areas covered by black alluvial soil deposits development of a systematic multidisciplinary database aided by gis with continuous monitoring and updating is also highly recommended and will be useful for further refined geotechnical microzonation it is the authors belief that this study highlights the basic constraints and hazards the city is facing and provides baseline information and awareness to the city planners decision makers geo environmentalists engineers and the community for future expansion and rehabilitation plans and to tackle the existing hazards

the 17 march 2005 kuzulu landslide sivas turkey and landslide susceptibility map of its near vicinity landslides are common natural hazards in the seismically active north anatolian fault zone of turkey although seismic activity heavy rainfall channel incisions and anthropogenic effects are commonly the main triggers of landslides on march 17 2005 a catastrophic large landslide in sivas northeastern of turkey the kuzulu landslide was triggered by snowmelt without any other precursor the initial failure of the kuzulu landslide was rotational following the rotational failure the earth material in the zone of accumulation exhibited an extremely rapid flow caused by steep gradient and high water content the agnus creek valley where kuzulu village is located was filled by the earth flow material and a landslide dam was formed on the upper part of agnus creek the distance from the toe of the rotational failure down to the toe of the earth flow measured more than 1800 m with about 12 5 million m3 of displaced earth material the velocity of the kuzulu landslide was extremely fast approximately 6 m s the main purposes of this study are to describe the mechanism and the factors conditioning the kuzulu landslide to present its environmental impacts and to produce landslide susceptibility maps of the kuzulu landslide area and its near vicinity for this purpose a detailed landslide inventory map was prepared and geology slope aspect elevation topographic wetness index and stream power index were considered as conditioning factors during the susceptibility analyses the conditional probability approach was used and a landslide susceptibility map was produced the landslide susceptibility map will help decision makers in site selection and the site planning process the map may also be accepted as a basis for landslide risk management studies to be applied in the study area

lateral variations in lithosphere strength in the romanian carpathians constraints on basin evolution lithospheric strength profiles constructed through extrapolation of rock mechanics data and constrained by crustal geophysics data demonstrate the existence of important spatial variations of thermomechanical properties in different domains of the romanian carpathians the pannonian basin and the transylvanian depression these models show important lateral variations in lithospheric rigidity along the southern and eastern carpathian foreland compatible with inferences from flexural modelling studies the modelling predicts an absence of mantle strength and the presence of weak lithosphere in the pannonian and transylvanian basins a nw se trending rheological transect is presented connecting the moesian platform the vrancea region of the carpathians the transylvanian basin and the apuseni mountains with the romanian part of the pannonian basin this transect demonstrates the existence of a close correlation of the inferred spatial variations in mechanical properties of the romanian lithosphere with observed patterns in large scale gravity anomalies and with tectonic units a notable feature of the rheological models is the presence of an intra carpathian weak zone the combination of a strong foreland lithosphere with a weak lithosphere in the inner part of the carpathian transylvanian pannonian system sheds light on a number of key features observed in the evolution of sedimentary basins in these areas remarkable differences in rheology predictions between flexural models and depth dependent rheology models indicate that the crustal lithosphere is detached from the mantle part of the lithosphere in the carpathian foreland

crustal structure of the alpine pannonian transition zone a combined seismic and gravity study the crustal structure of the transition zone between the eastern alps and the western part of the pannonian depression danube basin is traditionally interpreted in terms of subvertical tertiary strike slip and normal faults separating different alpine tectonic units reevaluation of approximately 4000 km long hydrocarbon exploration reflection seismic sections and a few deep seismic profiles together with data from approximately 300 wells suggests a different structural model it implies that extensional collapse of the alpine orogene in the middle miocene was controlled by listric normal faults which usually crosscut alpine nappes at shallow levels but at depth merge with overthrust planes separating the different alpine units the alternative structural model was tested along a transect across the danube basin by gravity model calculations and the results show that the model of low angle extensional faulting is indeed viable regarding the whole lithosphere of the western pannonian basin gravity modelling indicates a remarkable asymmetry in the thickness minima of the attenuated crust and upper mantle the approximately 160 km lateral offset between the two minima suggests that during the miocene extension of the pannonian basin detachment of the upper crust from the mantle lithosphere took place along a rheologically weak lower crust

landslide susceptibility mapping of vicinity of yaka landslide gelendost turkey using conditional probability approach in gis on 19 february 2007 a landslide occurred on the alaardic slope located 1 6 km south of the town of yaka gelendost turkey subsequently the displaced materials transformed into a mud flow in eglence creek and continued 750 m downstream towards the town of yaka the mass poised for motion in the yaka landslide source area and its vicinity which would be triggered to a kinetic state by trigger factors such as heavy or sustained rainfall and or snowmelt poise a danger in the form of loss of life and property to yaka with its population of 3 000 this study was undertaken to construct a susceptibility mapping of the vicinity of the yaka landslide s source area and to relate it to movement of the landslide mass with the goal of prevention or mitigation of loss of life and property the landslide susceptibility map was formulated by designating the relationship of the effecting factors that cause landslides such as lithology gradient slope aspect elevation topographical moisture index and stream power index to the landslide map as determined by analysis of the terrain through the implementation of the conditional probability method it was determined that the surface area of the goksogut formation which has attained lithological characteristics of clayey limestone with a broken and separated base and where area landslides occur possesses an elevation of 1 100 1 300 m a slope gradient of 15 35 and a slope aspect between 0 67 5 and 157 247 loss of life and property may be avoided by the construction of structures to check the debris mass in eglence creek the cleaning of the canal which passes through yaka the broadening of the canal s base area elevating the protective edges along the canal and the establishment of a protective zone at least 10 m wide on each side of the canal to deter against damage from probable landslide occurrence and mud flow

intraplate volcanism in the danube basin of nw hungary 3d geophysical modelling of the late miocene pasztori volcano three dimensional geophysical modelling of the early late miocene pasztori volcano ca 11 10 ma and adjacent area in the little hungarian plain volcanic field of the danube basin was carried out to get an insight into the most prominent intra crustal structures here we have used gridded gravity and magnetic data interpreted seismic reflection sections and borehole data combined with re evaluated geological constraints based on petrological analysis of core samples from available six exploration boreholes the volcanic rocks consist of a series of alkaline trachytic and trachyandesitic volcanoclastic and effusive rocks the measured magnetic susceptibilities of these samples are generally very low suggesting a deeper magnetic source the age of the modelled pasztori volcano buried beneath a 2 km thick late miocene to quaternary sedimentary sequence is 10 4 0 3 ma belonging to the dominantly normal c5 chron our model includes crustal domains with different effective induced magnetizations and densities uppermost 0 3 1 8 km thick layer of volcanoclastics underlain by a trachytic trachyandesitic coherent and volcanoclastic rock units of a maximum 2 km thickness with a top situated at minimal depth of 2 3 km and a deeper magmatic pluton in a depth range of 5 15 km the 3d model of the danube basin is consistent with observed high z magnetic anomalies above the volcano while the observed bouguer gravity anomalies correlate better with the crystalline basement depth our analysis contributes to deeper understanding of the crustal architecture and the evolution of the basin accompanied by alkaline intraplate volcanism

alpine tectonics of the pannonian basin the neogene evolution of the pannonian basin is fairly well understood in terms of back arc extension behind the carpathian thrust fold belt this middle miocene holocene basin however is superimposed on an earlier middle eocene early miocene basin traditionally called the paleogene basin of hungary although the paleogene stratigraphy of the basin is well known its structural evolution is not clear however a transtensional origin is assumed analogous to the overlying pannonian basin the existing data set on the paleogene basin can be integrated easily into a compressional basin model other intra carpathian paleogene basins such as the transylvanian and slovenian basins are now considered to be flexural in origin systematic interpretation of reflection seismic data shows that these tertiary basins are superimposed on a cretaceous alpine thrust fold belt the internal geometry of this belt in the basement of the pannonian basin indicates a close relationship to the surrounding mountain belts alps carpathians and dinarides whereas the neogene pannonian basin is in a mature stage of exploration the underlying paleogene flexural basins are much less explored furthermore the cretaceous thrust fold belts should be regarded as frontier areas for future oil and gas exploration efforts

towards a mechanical model for the formation of the pannonian basin abstract new maps showing crustal and lithospheric thickness variations in the pannonian basin and the surrounding east alpine carpathian and dinaric mountains have been prepared on the basis of recent seismic seismologic and electromagnetic data a map presenting miocene faults of regional significance has been also constructed for the same region by using a wealth of recently available national and or more local studies it is suggested that observed crustal and lithospheric structural contrasts have been controlled primarily by neogene kinematic history of the region kinematic history is characterized by the following main patterns 1 1 indentation by adria and large scale backthrusting in the southern alps 2 2 eastward escape and extension of the eastern alps 3 3 extensional collapse in the pannonian basin area 4 4 formation of broad wrench fault systems along strike in the dinarides and southern carpathians and the western carpathians with dextral and sinistral shear respectively 5 5 compression and accretion of the external thrust and fold belt in the eastern carpathians these kinematic patterns are thought to be interrelated and all are manifestations of the late stage evolution of an overthickened orogenic wedge in order to arrive at a better understanding of the mechanism of extension which formed the pannonian basin deep crustal seismic profiles hydrocarbon exploration reflection lines and borehole data have been analyzed in the little hungarian plain this plain represents the transition zone between the alps and the pannonian lowlands and the results are illustrated by eight interpreted cross sections one result of regional importance is the clear recognition that the transdanubian central range at the southeastern flank of the little hungarian plain is composed of alpine pre senonian thrust sheets this finding marks the end of a century of debate the allochthony of the substrata of the pannonian basin can be now considered proven another result of more general interest is that these cross sections document the mode of lithospheric extension preexisting compressional detachment planes reactivate as low angle normal faults and lead to tectonic unroofing of deeply buried metamorphic terranes characterized by ductile flow along subhorizontal lineation

landslide hazard mapping using an expert system and a gis this paper presents a rule based expert system used to create landslide warning and alert maps using as input change of landuse data from earth observation as well as geological rainfall and earthquake data stored in a geographic information system the difference with other systems is in the use of change differential input data the system is tested with 16 documented landslides it can predict 11 of the 16 landslides to be among the 10 most at risk pixels in the area of study which covers 100 km2

tectonic control of complex slope failures in the ameka river valley lower gibe area central ethiopia implications for landslide formation abstract even though major faults represent important landslide controlling factors the role the tectonic setting in actively spreading rifts plays in the development of large complex landslides is seldom discussed the ameka complex landslide area is located on the eastern scarp of the gibe gorge approximately 45 km to the west of the main ethiopian rift and 175 km to the southwest of addis ababa investigation of the complex landslide failures required a combination of satellite and airborne data based geomorphology geological field survey complemented with structural analysis radiocarbon geochronology and vertical electric sounding the obtained observations confirmed the multiphase evolution of the landslide area we have documented that apart from climatic and lithological conditions the main triggering factor of the ameka complex landslide is the tectonic development of this area the e w extension along the nne ssw trending main ethiopian rift is associated with the formation of numerous parallel normal faults such as the gibe gorge fault and the almost perpendicular scissor faults the geometry of the slid blocks of coherent lithology have inherited the original tectonic framework which suggests the crucial role tectonics play in the fragmentation of the compact rock masses and the origin and development of the ameka complex landslide area similarly the main scarps were also parallel to the principal tectonic features the local tectonic framework is dominated by faults of the same orientation as the regional structures of the main ethiopian rift such parallel tectonic frameworks display clear links between the extension of the main ethiopian rift and the tectonic development of the landslide area the ameka complex landslide developed in several episodes over thousands of years according to the radiocarbon data the last of the larger displaced blocks representing only 2 of the total area most likely slid down in the seventh century ad the main scarps namely the high scarps in the western part are unstable over the long term and toppling and falling type slope movements can be expected here in the future

inventory of landslides and susceptibility mapping in the dessie area northern ethiopia abstract a comprehensive study of landslide processes was carried out in the city of dessie and its environs in northern ethiopia the study area consists of a graben bounded by steep fault scarps and characterized by highly weathered tertiary basaltic rocks covered with quaternary deposits a method of landslide susceptibility mapping that adapts to the area of the hillside about 16 km2 is presented first a preliminary zoning was made by dividing the area into a discrete number of smaller units having similar susceptibility to sliding followed by semi quantitative field investigation of the geological geotechnical geomorphological hydrogeological and anthropogenic factors that contribute to the susceptibility of the units to landslide activity the final landslide susceptibility map was accomplished by using classical overlay procedures of established maps representing the different influencing factors the validity of the method was checked by means of a landslide hazard map that showed the actual distribution of landslide episodes that have occurred in the past finally four broad landslide susceptibility zones and 22 specific active landslide sites were identified the most important landslide types were complex earth and debris slides and flows in silty clay soils associated with alluvial and colluvial deposits overlying highly weathered basalts intact basaltic rocks experienced rock fall and toppling in steep slope areas large scale landslides have been initiated mostly by surface water and groundwater during the wet season

two phase cement grout propagation in homogeneous water saturated rock fractures abstract modeling of cement grout flow in rock fractures is important for the design monitoring and execution of rock grouting that is widely used in a variety of rock engineering applications this study presents a mathematical model based on the reynolds flow equation for cement grout flow in a homogeneous water saturated rock fracture the model is based on two phase flow i e grout as a bingham fluid and groundwater as a newtonian fluid and is used for investigating the importance of the water phase in rock grouting the modeling results for the two phase flow generally show the importance of the water phase that can significantly affect the pressure distribution and grout penetration in the fracture especially under the condition of grout hardening such effects depend on the viscosity ratio between the grout and groundwater which becomes increasingly important for cases with smaller values of the viscosity ratio the grout density also affects the grout penetration length applying an analytical solution based on single phase flow i e neglecting the impact of groundwater flow for modeling grout injection will generally overestimate the penetration length

geologic topographic and climatic controls in landslide hazard assessment using gis modeling a case study of souk ahras region ne algeria abstract landslides are the most common hazard in mountainous regions of northeast algeria in this study landslide hazard zonation of souk ahras province was carried out using a raster based gis and statistical processing landslide locations were defined from interpretation of aerial photographs and field surveys rotational planar and complex landslides were identified to reveal the controlling factors of landslides a temporal distribution of 603 recognized landslides 1981 2011 is compared with the monthly precipitation variation indicating a strong correlation between precipitation and landslide occurrence the correlation between landslide and lithology slope angle and elevation shows the same results tabular data maps and satellite images were collected processed and constructed into a spatial database in a gis platform the factors that influence landslide occurrence such as slope angle slope exposition and elevation were derived from the dem lithology soil deposits and faults were digitalized from the geologic maps roads streams and timber were extracted from landsat image precipitation was krigged from pluviometric measurement dataset different classes of thematic layers were assigned a corresponding rating value as attribute information and an attribute map was generated for each data layer in the gis landslide hazard areas were assessed and mapped using the landslide occurrence and permanent factor maps by applying a probabilistic method with a logistic regression approach the results of the analysis were verified using landslides location map compared with the probability model the resulting map can be used to mitigate this hazard and to plan land use and urbanization

modelling recent deformation of the pannonian lithosphere lithospheric folding and tectonic topography article i nfo we investigated the role of lithospheric folding in the quaternary inversion of the pannonian basin by a series of analogue models to this aim build up of stresses due to intraplate compression in the hot and weak pannonian lithosphere changes in the style of deformation and related surface processes were modelled the primary response of the lithosphere to compression appears to be deformation in the form of large scale folding as a consequence of the folding differential crustal motions occur affecting present day surface morphology and landscape processes the analogue experiments examined folding mechanisms of the hot pannonian lithosphere characterised by extremely low strengths except for a thin layer of brittle upper crust modelling results confirmed the existence of a large wavelength 350 400 km component of deformation accounting for large scale vertical crustal motions the amplitude of folding is sufficient to generate the amount of observed uplift and subsidence our analogue models supported by the results of stress analyses suggest that despite the low rate of convergence between the adriatic microplate adria push and the european plate the weak pannonian lithosphere has been an efficient transmitter of compression during the basin inversion crustal thickness variations are of key importance in governing regional deformation pattern and influence the timing and extent of the basin inversion effects of alternating strong and weak units in the brittle crust were also examined by means of two series of conceptual models in which the order of thin and thick crustal blocks was opposite strain localisation in the brittle crust was strongly controlled by the moderate initial thickness variations the concept gives a plausible explanation for the presence of anomalous rates of uplift and subsidence and multi wavelength folding inside the basin models taking into account horizontal movements due to lateral extrusion were constructed with an oblique face of the indenter this kinematic boundary condition resulted in a complex internal structure of the folded layers the presented analogue experiments together with previous numerical modelling studies demonstrate the link between large scale lithospheric folding and topography evolution in the pannonian basin system

crustal structure in the carpatho pannonian region insights from three dimensional gravity modelling and their geodynamic significance a three dimensional gravity modelling of the carpatho pannonian region was carried out to get a better image of the moho boundary and the most prominent intra crustal density heterogeneities at first only the major density boundaries were considered the bottom of the tertiary basin fill the moho discontinuity and the lithosphere to asthenosphere boundary density contrasts were represented by relative densities the improved density model shows a transitional unit of high density at the base of the crust along the teisseyre tornquist zone in the western carpathians an extensive relatively low density unit was inferred in mid crustal levels the border zone between the southern carpathians and the transylvanian basin is characterized by a sharp step like contact of the two crustal units the moho configuration reveals important information on the tectonic evolution of the region zones of continental collision are represented by thick moho roots eastern alps eastern carpathians transpressional orogenic segments however are different in the western carpathians the moho is a flat surface in the dinarides a medium moho root is observed the southern carpathians are characterized by a thick crustal root the differences are explained with the presence or absence of subductible oceanic crust along the carpathians during the extrusion of pannonian blocks

on the origin and fluid content of some rare crustal xenoliths and their bearing on the structure and evolution of the crust beneath the bakony balaton highland volcanic field w hungary rarely occurring clinopyroxene plagioclase bearing felsic granulite and skarn xenoliths were studied from the mantle and crustal xenolith bearing alkaline basaltic and pyroclastic localities of the bakony balaton highland volcanic field w hungary geobarometry and geothermometry of the xenoliths made it possible to categorise them in three groups according to their depth of formation the first group formed in the lower crust together with mafic and metasedimentary granulites the second group represents magmatic intrusions of the middle crust and the third one comprises contact metamorphic rocks of relatively shallow origin the calculated pressure difference from the core and rim compositions of plagioclase and clinopyroxene as well as garnet breakdown reactions in some xenoliths show evidence for pressure decrease due to crustal thinning both in lower crustal and middle crustal xenoliths during formation of the pannonian basin fluid inclusion studies reveal the dominance of the co2 rich fluids in the whole crustal section in contrast with fluids found in mafic garnet bearing xenoliths crustal stratigraphy was constructed for the periods prior to the extension and after the extension on the basis of geobarometry and geophysical data on the basis of mineral stabilities and geothermo barometry we estimated that the pre extensional thickness of the lower and upper crust may have been 27 34 and 26 28 km respectively comparison of pre extensional and present day thickness of the lower and upper crust indicate that thinning affected both the lower and the upper portion of the crust but on a different scale the calculated thinning factors are between 2 25 and 3 4 for the lower crust and 1 3 1 56 for the upper crust

shear enhanced nonlinear flow in rough walled rock fractures abstract nonlinear flow in 3d rough walled rock fractures is simulated by solving the navier stokes equations the emphasis is on the impact of shear caused aperture changes variable apertures and asperity contacts and flow conditions inertial term upon nonlinear flow behavior in order to compare shear effects two 3d fracture models with and without shear were established with identical initial rough walled surfaces topographies of a realistic rock sample five groups of simulations with different inflow boundary conditions of flowrates reynolds numbers re were conducted to demonstrate shear enhanced nonlinearity of flow fields and limitations of local cubic law lcl approach the flow results clearly show channeling flow along the preferential paths transverse flow around the contact spots and eddy flows behind contact spots with increasing re which cannot be observed in 2d models the effective transmissivity of the 3d fracture model was calculated from the modeling results of velocity and pressure fields the results showed that the effective transmissivity is a function of local apertures with important uncertainties even when re is small i e re 0 4 in this study thus the validity of the transmissivity evaluation using lcl approach for nonlinear flow in 3d rough walled rock fractures is questionable

numerical simulations examining the relationship between wall roughness and fluid flow in rock fractures understanding how fracture wall roughness affects fluid flow is important when modeling many subsurface transport problems computed tomography scanning provides a unique view of rock fractures allowing the measurement of fracture wall roughness without destroying the initial rock sample for this computational fluid dynamics study we used several different methods to obtain three dimensional meshes of a computed tomography scanned fracture in berea sandstone these volumetric meshes had different wall roughnesses which we characterized using the joint roughness coefficient and the fractal dimension of the fracture profiles we then related these macroscopic roughness parameters to the effective flow through the fractures as determined from navier stokes numerical models thus we used our fracture meshes to develop relationships between the observed roughness properties of the fracture geometries and flow parameters that are of importance for modeling flow through fractures in field scale models fractures with high joint roughness coefficients and fractal dimensions were shown to exhibit tortuous flow paths be poorly characterized by the mean geometric aperture and have a fracture transmissivity 35 times smaller than the smoother modeled fracture flows

transform faulting extension and subduction in the carpathian pannonian region the carpathian arc formed during the cretaceous to miocene continental collision of europe with a smaller continental fragment following southward and westward subduction of an oceanic terrane during and after the last stages of thrusting in the outer carpathians a set of discrete basins opened up inside the carpathian loop these basins are regions of local extension which appear to be associated with strike slip faults in general northeast and northwest trending sets of conjugate shears reflect east west extension of the intra carpathian region during the middle and late miocene palinspastic reconstruction of the basins indicates approximately 75 to 100 km of extension comparable to the magnitude of synchronous crustal shortening in the east carpathians extension may have occurred to accommodate continued westward a type subduction after plate convergence was prohibited by geometrical constraints and suggests that in this region miocene subduction is driven by forces acting on the downgoing plate

a new approach to the electrical conductivity anomalies in the drauzug bakony geological unit abstract a major electrical conductivity anomaly has been detected in transdanubia west hungary in the eastern part of the drauzug bakony geological unit dbu a collision zone of the alpine orogeny assuming the source of the conductivity anomaly to be a characteristic formation of the whole dbu long period magnetotelluric mt measurements were made in two regions of the western part of the dbu in the gail valley and in the karawanken the general features of this formation were studied also in order to elucidate the cause of the transdanubian conductivity anomaly the conductivity anomaly detected by long period mt in the western dbu lies much deeper 12 17 km than in transdanubia 5 9 km as the anomaly in both regions is associated with a well known tectonic zone its origin was initially explained by ionic conduction arising from the presence of pore fluids the very low resistivity values the great anisotropy the effect of charges on the h polarized mt curves and the anomalous magnetic field variations also indicated an increase of electronic conduction possibly caused by graphitic rocks or ores nearer to the surface in the gail valley audiomagnetotelluric measurements made in 1986 have led to the discovery of these standing blocks of graphitic shales lifted up gradually to the surface by tectonic forces from below the dolomites of the carnic alps it is suggested that the same plate collision arranged the paleozoic graphitic shales to narrow dikes in the gail valley as well as in transdanubia along the balaton line and zones parallel to it

neotectonic control on river sinuosity at the western margin of the little hungarian plain abstract this study investigates the influence of neotectonic activity on river channel patterns in low relief areas our study area the westernmost part of the little hungarian plain belongs to the danube catchment in the transition zone between the eastern alps and western carpathians this area evolved within the pannonian back arc basin during the neogene and was also affected by the major lateral tectonic extrusion of the eastern alps water course analysis has been carried out on the leitha repce rabca ikva and wulka rivers to detect a possible relationship between their river courses and any on going tectonic activity that is otherwise difficult to detect in this poorly exposed low relief area in order to derive channel geometries hardly modified by human activity i e prior to the major river control works of the last 150 years calculations of river channel properties were based on georeferenced historical map sheets of the second military survey of the habsburg empire these recorded the channel patterns and geomorphologic situation around 1840 classic sinuosity values from the reconstructed river courses have been derived using several window sizes the calculated values show surprisingly strong local variations considering the low relief and lithological homogeneity of the area the spatial distribution of the pronounced sinuosity variations coincides with the location of late miocene faults well known from seismic data on going active tectonic activity along these faults is further indicated by the local earthquake record and geomorphic parameters derived from high resolution digital elevation models in conclusion river sinuosity calculations represent a sensitive tool for recognizing neotectonic activity in low relief areas

slab behaviour and its surface expression new insights from gravity modelling in the se carpathians abstract we use lithosphere scale gravity models to calculate gravity anomalies resulting from oceanic subduction continental collision slab steepening delamination and break off local isostasy was assumed for determining vertical movements caused by mass changes related to these tectonic processes our results show that subduction is accompanied by basin subsidence on the upper plate caused by the heavy lithospheric root of the subducting slab the basin evolution goes parallel with the slab evolution and shows considerable modifications when the processes at depth change slab steepening delamination break off characteristic gravity anomaly curves were acquired for the different tectonic scenarios these curves together with other data e g basin evolution on the upper and the lower plate were used for the reconstruction of the tectonic evolution of the se carpathians which includes tertiary subduction and collision followed by slab steepening and delamination

electrical resistivity tomography technique for landslide investigation a review abstract in the context of in situ geophysical methods the electrical resistivity tomography ert is widely used for the near surface exploration of landslide areas characterized by a complex geological setting over the last decade the technological improvements in field data acquisition systems and the development of novel algorithms for tomographic inversion have made this technique more suitable for studying landslide areas with a particular attention to the rotational translational and earth flow slides this paper aims to present a review of the main results obtained by applying ert for the investigation of a wide spectrum of landslide phenomena which affected various geological formations and occurred in different geographic areas in particular significant and representative results obtained by applying 2d and 3d ert are analyzed highlighting the advantages and drawbacks of this geophysical technique finally recent applications of the time lapse ert tl ert for landslide investigation and the future scientific challenges to be faced are presented and discussed

joint analysis of sar interferometry and electrical resistivity tomography surveys for investigating ground deformation the case study of satriano di lucania potenza italy abstract we have jointly applied microwave remote sensing imaging and ground based geophysical methodologies for investigating ground deformation in particular the differential interferometric synthetic aperture radar dinsar technique referred to as small baseline subset sbas algorithm and the electrical resistivity tomography ert method have been applied the former is a tool for investigating large areas allowing us to detect deformation phenomena and to analyse their spatial patterns and temporal evolution the latter permits us to reconstruct with high spatial resolution the geometry of near surface geological structures and to estimate the electrical resistivity of outcropping terrains the starting point of our analysis has been a dinsar survey carried out on an area of about 400 km2 centred around the town of potenza basilicata region italy for which sar data acquired by the ers 1 2 sensors in the time interval 1992 2000 were available the dinsar analysis allowed us to detect an unknown ground deformation effect which involves the urban area of satriano di lucania located close to potenza an on site ert survey was then carried out in order to characterize in detail the physical properties of the terrains involved in the main deformation pattern detected via the dinsar processing the integration of the dinsar and ert measurements permitted us to investigate areas where the deformation have space variant characteristics and allowed us to formulate a hypothesis on the origin of the detected displacement processes that although not fully conclusive is consistent with the overall dinsar and ert analysis

reduced carbonic fluids in mafic granulite xenoliths from the bakony balaton highland volcanic field w hungary abstract amphibole bearing and amphibole free garnet granulite xenoliths clinopyroxene plagioclase garnet orthopyroxene amphibole from two localities of the bakony balaton highland volcanic field sabar hegy and szentbekkalla were investigated by means of textural analysis mineral chemistry mineral equilibria geothermobarometry and fluid inclusion studies we have determined the p t path of these lower crustal xenoliths which begins at peak pressure between 0 9 and 1 4 gpa the peak pressure was followed by temperature increase of about 200 300 c and 0 3 0 7 gpa pressure decrease which is marked by breakdown reactions of garnet and pargasitic amphibole garnet broke down first to orthopyroxene anorthite spinel type 1 then to olivine plagioclase spinel type 2 symplectite amphibole broke down to form clinopyroxene plagioclase fe ti oxide melt orthopyroxene olivine mineral assemblage these changes in p t conditions were caused by crustal thinning the present day crustal thickness max 32 km indicates that garnet granulites are no longer stable in the lower crust of the pannonian basin the calculated crustal thinning factor is between 1 6 and 1 8 in accordance with the values calculated from tectonic methods a unique co2 co c fluid system which has not been described from the lower crust so far occurs in inclusions of the rock forming minerals mainly in plagioclase and clinopyroxene a primary and two secondary fluid inclusion fi generations were identified on the basis of textural analyses and distribution of homogenization temperatures primary fis are connected to the formation of garnet granulite the older secondary generation was trapped after the main temperature increase and some pressure decrease during crustal thinning the younger secondary generation trapped within the depth limits of the present lower crust at pressures between 0 6 0 7 gpa the overall composition of the fluid system has not changed during crustal thinning the calculated oxygen fugacity values are slightly above and under qfm between 10 8 5 and 10 10 1 at 1200 c

landslide susceptibility mapping for a part of tectonic kelkit valley eastern black sea region of turkey considering damage to man made structures by natural hazards in turkey landslides are the second most important hazard after earthquakes for this reason a large scale study titled turkish landslide inventory project has been carried out since 1998 during this project some special susceptibility hazard and risk assessments have been performed in this study a landslide susceptibility map of a part of tectonic kelkit valley in the north of central turkey was produced employing binary logistic regression analyses to achieve the most appropriate results some sensitivity analyses were also carried out for this purpose four different data sets were constructed considering conditioning factors used and sampling strategies applied for the training data sets in this study as a consequence of the analyses the most proper outcomes were obtained by using the data set in which continuous topographical parameters and lithological dummy variables were implemented together and 50 of training data set was taken from seed cells at random correct classification percentage and root mean square error rmse values for the validation data for that case were estimated as 84 16 and 0 36 respectively this prediction capability shows that the landslide susceptibility map produced in this research paper can be used for the planning of protective and mitigation measures in the region

tectonic conditioning revealed by seismic refraction facilitates deep seated landslides in the western escarpment of the main ethiopian rift abstract landslide is a geo hazard phenomenon that has been taking lives and causing severe property damages all over the world mostly in mountainous areas the main ethiopian rift has a unique tectonic setting with complex geological and geomorphological features coupled with continuously deteriorating environmental conditions which made its escarpments vulnerable for landslides the study area is located near the debre sina town within the yizaba wein locality which has been severely affected by frequent landslide problems this work was carried out using a multidisciplinary approach based on geological geomorphological kinematic analysis and geophysical survey seismic refraction investigations were carried out along the yizaba wein landslide main scarp to determine the depth to the bedrock and to the failure plane to assess the stability of the slope to locate possible structural features and to identify the extent of recent landslide activity and to study the subsurface situation the seismic measurements were made along three nearly orthogonal survey lines in the recently affected area a high resolution 2d p wave survey was conducted using a 24 channel seismic unit the seismic refraction results revealed four layers of geomaterials with distinct physical characteristics that contained a subsurface landslide anomaly within the layers the layers were interpreted according to the major lithological units from top to bottom i clay loosely cemented colluvial sediments and highly weathered agglomeratic basalt ii highly to moderately fractured porphyritic basalt ignimbrite volcanic ash and rhyolite trachyte iii moderately to slightly fractured ignimbrite rhyolite trachyte and basalt and iv very strong massive fresh rock bedrock faults and weak zones have also been identified in the bedrock based on the abundance of fractures and subsidiary faults resulting from damage of rocks and change of lithology due to variable fault rock formation strongly influencing the wavefield distribution which usually causes a local decrease of the velocity value the main findings show that the landslide in the yizaba wein locality was caused by its complex geological structural setting and downslope movement of the underlying pyroclastic sediment facilitated by heavy rainfall considering the similar geological and tectonic settings similar mechanisms can be assumed for other landslides along the rift margins and associated highlands of ethiopia

landslide displacement prediction based on multi source data fusion and sensitivity states abstract owing to the complexity of the coupling relationship between multiple external triggering factors and the internal sensitivity state of landslides it is difficult to accurately predict the displacement response of landslides to triggering factors using existing methods to overcome this setback two new concepts namely the trend sequence and sensitivity states were introduced to quantificationally characterize landslide displacement caused by external factors and the landslide internal states respectively the support vector regression method was used to predict the trend sequence while the long short term memory neural network was employed to predict the sensitivity state thereafter by fusing the predicted trend sequence and the sensitivity state a non linear model for landslide displacement prediction was proposed moreover with the baishuihe landslide located in the three gorges reservoir area as a case study the proposed model was evaluated and validated using a large quantity of rainfall reservoir water level and displacement monitoring data spanning a period of over 11 years based on the results obtained the performance of the proposed model with respect to landslide displacement prediction was satisfactory furthermore compared with three existing traditional prediction models of landslide displacement the proposed model achieved a higher accuracy therefore this study is helpful because it provides new insights that can be used to develop deep data mining approaches for landslide displacement prediction

mesozoic and tertiary evolution of the alpine carpathian foreland in eastern austria abstract the bohemian massif partly covered by mesozoic sediments extends southward some 50 km under the alpine carpathian nappe complex a major basement spur devoid of mesozoic sediments and referred to as the south bohemian basement spur separates the jurassic cretaceous upper austrian basin from the lower austrian basin the latter came into evidence during the middle jurassic under a tensional setting late jurassic shelf carbonates and basinal shales were deposited under a tectonically quiet regime early cretaceous uplift of the south bohemian basement spur induced the truncation of jurassic strata along its margins transgressive late cretaceous elastics overlap the truncated jurassic series and locally onlap on basement upper austria latest cretaceous to paleocene foreland deformations may have caused a renewed uplift of the south bohemian basement spur the eocene to late miocene evolution of the molasse foredeep went hand in hand with the emplacement of the alpine carpathian nappe system differential movements between the eastern alpine nappes and the carpathian nappes combined with tensional stresses in the basement caused the subsidence of the vienna basin

gravity constraints on the crustal structure and slab evolution along a transcarpathian transect abstract a new unified bouguer anomaly map of the carpathian arc and the pannonian basin has been compiled from previously prepared and recently published gravity maps in order to constrain the crustal structure and the tectonic evolution of the area a two dimensional gravity model is presented along a western carpathians pannonian basin southern carpathians transect the model is based on deep seismic lines where available and on detailed geological sections the results confirm that the extensional crustal structure of the pannonian basin revealed by deep seismic surveys agrees with the gravity data furthermore they suggest that the western and southern carpathians area at different stages of their evolution the subducted oceanic slab under the western carpathians has already been assimilated to the asthenosphere while a crustal slab is still present under the southern carpathians these findings are compatible with the observation that the last major phase of crustal shortening terminated at the early middle miocene in the western carpathians but continued throughout the pliocene in the southern carpathians

rheology predictions across the western carpathians bohemian massif and the pannonian basin implications for tectonic scenarios on the basis of extrapolation of failure criteria lithology and temperature models we predict the rheology of the lithosphere for several sections through the carpathians and surrounding regions our models show significant lateral variations in rheology for the different tectonic units with important implications for the tectonic evolution the theologically strong lithosphere of the polish platform area contrasts with the weak lithosphere of the pannonian basin indicating that the arcuate shape of the carpathian orogen is primarily caused by an inherited curvature of an ancient embayment in the foreland with the pannonian units passively filling the space the polish platform and the moesian platform exhibit a similar rheological anisotropy caused by nw se trending weakness zones paralleling the tornquist teisseyre zone this anisotropy was the main controlling factor on the behavior of the lithosphere in this area since cadomian times as documented by the geological evolution of the sudety mountains and the mesozoic polish trough including the late cretaceous alpine inversion and the neogene development of the carpathian foreland this rheological anisotropy appears to have a major controlling impact on the development of at least the eastern part of the european lithosphere rheology predictions for the bohemian massif support the idea that the rigid lithosphere of the bohemian massif governed the bending of the alpine carpathian transition zone expressed in the large scale wrench movements opening the vienna basin in the foreland area detachment levels are predicted for upper and lower crustal levels leading to a decoupling of crustal and subcrustal flexure in most areas comparison with basin formation models indicates that our predictions for effective elastic thickness eet are similar to those derived from flexural models for the foreland area also eet predictions from extensional basin models in the pannonian region yield values close to our findings

a new parameter to assess hydromechanical effects in single hole hydraulic testing and grouting grouting or filling of the open voids in fractured rock is done by introducing a fluid grout through boreholes under pressure the grout may be either a newtonian fluid or a bingham fluid the penetration of the grout and the resulting pressure profile may give rise to hydromechanical effects which depend on factors such as the fracture aperture the pressure at the borehole and the rheological properties of the grout in this paper we postulate that a new parameter a which is the areal integral of the fluid pressure change over the fracture plane is an appropriate measure to describe the change in fracture aperture volume due to a change in effective stress in many cases analytic expressions are available to calculate pressure profiles and the a parameter the approach is verified using a fully coupled hydromechanical simulator for the case of a newtonian fluid results of the verification exercise show that the new approach is reasonable and that the a parameter is a good measure for the fracture volume change i e the larger the a parameter the larger the fracture volume change in an almost linear fashion to demonstrate the application of the approach short duration hydraulic tests and constant pressure grouting are studied it is concluded that using analytic expressions for penetration lengths and pressure profiles to calculate the a parameter provides a possibility to describe a complex situation and compare discuss and weigh the impact of hydromechanical couplings for different alternative grouting strategies further the analyses identify an effect of high pressure grouting that of uncontrolled grouting of larger fractures and insufficient or less than expected sealing of finer fractures under certain grouting conditions

latest pannonian and quaternary evolution at the transition between eastern alps and pannonian basin new insights from geophysical sedimentological and geochronological data the transition zone between eastern alps and pannonian basin is a key area for the investigation of the interplay between regional uplift local tectonic subsidence and depositional environment our study area the western margin of the little hungarian plain is characterized by gentle hills plateaus and depressions of which several are filled by lakes including one of austria s largest and shallowest lakes lake neusiedl geological investigation is hampered by the scarcity of outcrops and thus direct observation of sedimentological or structural features is difficult despite a long research history in the area a consistent landscape evolution model considering all relevant constraints is lacking so far in this study we apply multidisciplinary methods to decipher the complex tectonic and fluvial depositional evolution of the region local data from shallow lake drilling and seismic investigation are combined with regional data from industrial seismics and core data to gain new insights into the latest pannonian late miocene and quaternary evolution shallow lake seismic data show the erosionally truncated pannonian sediments dipping and thickening toward southeast toward the modern depocenter of the little hungarian plain overlying quaternary fluvial sediments show a very similar thickening trend except for the area on the plateau north of the lake indicating ongoing subsidence in major parts of the basin drill cores from locations along the lake seismic lines were analyzed concerning their age mineralogy and heavy minerals and compared with outcrop samples from the surrounding plains and the plateau to derive indications on sediment provenance a key observation is the apparent lack of a significant gravel layer on top of the tilted pannonian sediments beneath lake neusiedl small scale faults can be observed in the lake seismic sections along with key sedimentary features significant differences of the current elevation of the top pannonian between the surrounding plains and the plateau indicate post pannonian normal faulting which is a key process in shaping the present day morphology of the region luminescence ages of samples from the quaternary fluvial gravels on top of the pannonian sediments are a significantly higher 300 ka compared to the gravels in the plain 102 11 and 76 8 ka suggesting ongoing tectonic subsidence

a preliminary stripped gravity map of the pannonian basin abstract by removing the gravity effects of the known near surface sources from the gravity map we obtain a stripped gravity map that enables a better interpretation of the deep seated geological structures of the earth s crust the total gravity effect of anomalous bodies is acquired by summation of the gravity effects of n sided vertical prisms with horizontal bases the stripping procedure has a more accurate physical foundation than any other mathematical method of gravity field analysis provided that the geometry and density of the disturbing bodies are known with sufficient accuracy this method was applied to the pannonian basin

spatial patterns causes and consequences of landslides in the gilgel gibe catchment sw ethiopia abstract the gilgel gibe catchment in sw ethiopia is one of the areas in east africa affected by landslides to better understand the patterns and the causal factors of these landslides all landslides in a small study area 14 km in the hilly parts of the gilgel gibe catchment were mapped and analyzed in total 60 landslides were mapped these landslides caused a displacement of 1 million m slope material which corresponds to a mean displaced volume of 50 ton ha 1 y 1 in the last 20 years moreover many landslides deliver directly sediment to the rivers and hence increase the sediment load in the rivers this soil loss to the rivers was estimated at 11 ton ha 1 y 1 during the same period high annual rainfall ca 2000 mm y 1 lithological and pedological properties and to a lesser extent steep 16 slopes turn the area into an inherent unstable situation and can be indicated as preconditions for the landslides in the study area distance to rivers is significantly the most important precondition as slopes near rivers are less stable than slopes further away from the rivers this is mainly caused by river incision and bank erosion which often occur in the area and which can be attributed to increased runoff due to deforestation over the past 20 years therefore recent deforestation caused more shallow landslides but also indirectly more deep seated landslides close to the rivers heavy rainfall is indicated as the main triggering factor for almost all landslides

channeling with diffusion into stagnant water and into a matrix in series numerous field observations show that most water flow in fractured rocks takes place in only a small part of the fractures we call these channels solutes in the flowing water can diffuse in and out of stagnant water in the porous rock matrix that the flowing water contacts via the so called flow wetted surface fws in addition the solutes can diffuse into stagnant water in the fractures themselves and from this water further into the rock matrix for narrow channels with small fws the transport via the stagnant water in the fracture can considerably add to the exchange of solutes between flowing water and matrix water for sorbing solutes that interact with the micropore surfaces in the matrix the effect can be very strong some models that account for these processes are developed and solved using laplace transforms some examples are presented that show the effects of first diffusion into stagnant waters in fractures with subsequent diffusion into the rock matrix effects of slit like and tube like channels are considered as well as the presence of intersecting fractures the solutions are especially useful to model solute transport in complex three dimensional channels networks where wide and narrow or even tube like channels with widely varying flow rates combine into a multitude of different paths

geomorphic expression of neotectonic activity in a low relief area in an airborne laser scanning dtm a case study of the little hungarian plain pannonian basin abstract the nw corner of the little hungarian plain which lies at the junction of the eastern alps the pannonian basin and the western carpathians is a neotectonically active region linking the extrusional tectonics of the eastern alps with the partly subsiding little hungarian plain the on going deformation is verified by the earthquake activity in the region an extremely flat part of the area east of neusiedlersee the so called seewinkel has been investigated with airborne laser scanning als also known as airborne lidar techniques resulting in a digital terrain model dtm with a 1 m grid resolution and vertical precision of better than 10 cm the dtm has been compared with known and inferred neotectonic features potential neotectonic structures of the dtm have been evaluated together with geological maps regional tectono geomorphic studies geophysical data earthquake foci as well as geomorphological features and the quaternary sediment thickness values of the seewinkel and the adjacent parndorfer plateau a combined evaluation of these data allows several tectonic features with a relief of

lithospheric memory and stress field controls on polyphase deformation of the pannonian basin carpathian system abstract the pannonian basin carpathian system displays pronounced lateral variation in lithopsheric structure and sedimentary basin configuration the tectonic history of the system is characterised by a polyphase history with late miocene extension in the pannonian basin and simultaneously occurring compression in the carpathian arc pre existing structures play a key role in subsequent basin reactivation explaining anomalous features in subsidence characteristics and inferred thinning factors the area exhibits a relatively high level of neotectonic activity imaged by high resolution seismic data intraplate seismicity and stress indicator data major parts of the system have experienced a rapid late neogene uplift and erosion amounting up to several kilometres in the romanian carpathians a major part of the present basin configuration previously primarily attributed to basin formation mechanisms such as stretching in the pannonian basin and lithospheric flexure in the carpathians appears to be strongly affected by recent deformation postdating basin formation of the pannonian basin and the carpathian foredeep these findings affect modelling predictions of basin subsidence sediment sourcing thermal evolution and hydrodynamic regime with implications for hydrocarbon play concepts in the area

tectonic units of the alpine collision zone between eastern alps and western turkey abstract we present a map that correlates tectonic units between alps and western turkey accompanied by a text providing access to literature data explaining the concepts used for defining the mapped tectonic units and first order paleogeographic inferences along strike similarities and differences of the alpine eastern mediterranean orogenic system are discussed the map allows 1 for superimposing additional information such as e g post tectonic sedimentary basins manifestations of magmatic activity onto a coherent tectonic framework and 2 for outlining the major features of the alpine eastern mediterranean orogen dinarides hellenides anatolides and taurides are orogens of opposite subduction polarity and direction of major transport with respect to alps and carpathians and polarity switches across the mid hungarian fault zone the dinarides hellenides taurides and apennines consist of nappes detached from the greater adriatic continental margin during cretaceous and cenozoic orogeny internal units form composite nappes that passively carry ophiolites obducted in the latest jurassic earliest cretaceous or during the late cretaceous on top of the greater adriatic margin successions the ophiolites on top of composite nappes do not represent oceanic sutures zones but root in the suture zones of neotethys that formed after obduction suturing between greater adria and the northern and eastern neotethys margin occupied by the tisza and dacia mega units and the pontides occurred in the latest cretaceous along the sava izmir ankara erzincan suture zones the rhodopian orogen is interpreted as a deep crustal nappe stack formed in tandem with the carpatho balkanides fold thrust belt now exposed in a giant core complex exhumed in late eocene to miocene times from below the carpatho balkan orogen and the circum rhodope unit its tectonic position is similar to that of the sakarya unit of the pontides we infer that the rhodope nappe stack formed due to north directed thrusting both rhodopes and pontides are suspected to preserve the westernmost relics of the suture zone of paleotethys

roughness decomposition and nonlinear fluid flow in a single rock fracture abstract the objective of this paper is to investigate the effects of wall surface roughness on fluid flow through rock fractures a wavelet analysis technique was developed to define a mathematical criterion for decomposing the original wall surface roughness profiles of a fracture into a high frequency secondary roughness profile and a low frequency primary roughness profile in order to examine their impacts on fluid flow by solving the navier stokes equations nse without linearization using a self developed 2d finite volume method fvm code the results indicate that the high frequency secondary roughness is the main cause for dynamic evolution of eddy flow regions in the fracture flow field besides the reynolds number re in the original fracture model with the high frequency secondary roughness our results show that fluid flow fields are not only generally non linear but also with non stop generation and motions of eddies in the boundary layer regions of rough fractures when the re 1000 in this study which will affect the solute transport processes in fractured rock masses the complete nse were solved without removing acceleration and inertial terms so that the impacts of surface roughness on the nonlinear and dynamic flow behavior of rock fractures were calculated and visualized more accurately which is important for modeling mass and energy transport processes in fractures and fractured rock masses

cement grout propagation in two dimensional fracture networks impact of structure and hydraulic variability abstract analysis of cement grout propagation in water saturated two dimensional discrete fracture networks is presented in this study a two phase flow model for bingham fluids flow in a single saturated fracture is extended to simulate cement grouts propagation in saturated networks using this extended model the impacts of network structure and hydraulic variability i e network geometry and aperture distribution on the propagation process are investigated through numerical simulations cement grout propagation in 50 realizations of a two dimensional discrete fracture network 2d dfn are simulated with different cases of aperture variability i e constant aperture uncorrelated and length correlated heterogeneous apertures following a truncated lognormal distribution the results indicate that network structure and hydraulic variability significantly affect the grout propagation in 2d dfn systems the randomized network structure and uncorrelated heterogeneous apertures significantly delay the propagation rate and largely increase the variability range of the propagation volume fraction in contrast in the case with length correlated heterogeneous apertures the propagation rate increases while the variability range and rate of change of the propagation volume fraction decreases the extended two phase flow model for fracture networks and the simulation results presented in this work are useful for basic understanding of the processes relevant for design monitoring and execution of rock grouting

application of logistic regression for landslide susceptibility zoning of cekmece area istanbul turkey as a result of industrialization throughout the world cities have been growing rapidly for the last century one typical example of these growing cities is istanbul the population of which is over 10 million due to rapid urbanization new areas suitable for settlement and engineering structures are necessary the cekmece area located west of the istanbul metropolitan area is studied because the landslide activity is extensive in this area the purpose of this study is to develop a model that can be used to characterize landslide susceptibility in map form using logistic regression analysis of an extensive landslide database a database of landslide activity was constructed using both aerial photography and field studies about 19 2 of the selected study area is covered by deep seated landslides the landslides that occur in the area are primarily located in sandstones with interbedded permeable and impermeable layers such as claystone siltstone and mudstone about 31 95 of the total landslide area is located at this unit to apply logistic regression analyses a data matrix including 37 variables was constructed the variables used in the forwards stepwise analyses are different measures of slope aspect elevation stream power index spi plan curvature profile curvature geology geomorphology and relative permeability of lithological units a total of 25 variables were identified as exerting strong influence on landslide occurrence and included by the logistic regression equation wald statistics values indicate that lithology spi and slope are more important than the other parameters in the equation beta coefficients of the 25 variables included the logistic regression equation provide a model for landslide susceptibility in the cekmece area this model is used to generate a landslide susceptibility map that correctly classified 83 8 of the landslide prone areas

influence of fracture scale heterogeneity on the flow properties of three dimensional discrete fracture networks dfn while permeability scaling of fractured media has been so far studied independently at the fracture and network scales we propose a numerical analysis of the combined effect of fracture scale heterogeneities and the network scale topology the analysis is based on 2 106 discrete fracture network dfns simulations performed with highly robust numerical methods fracture local apertures are distributed according to a truncated gaussian law and exhibit self affine spatial correlations up to a cutoff scale lc network structures range widely over sparse and dense systems of short long or widely distributed fracture sizes and display a large variety of fracture interconnections flow bottlenecks and dead ends at the fracture scale accounting for aperture heterogeneities leads to a reduction of the equivalent fracture transmissivity of up to a factor of 6 as compared to the parallel plate of identical mean aperture at the network scale a significant coupling is observed in most cases between flow heterogeneities at the fracture and at the network scale the upscaling from the fracture to the network scale modifies the impact of fracture roughness on the measured permeability this change can be quantified by the measure a2 which is analogous to the more classical power averaging exponent used with heterogeneous porous media and whose magnitude results from the competition of two effects i the permeability is enhanced by the highly transmissive zones within the fractures that can bridge fracture intersections within a fracture plane ii it is reduced by the closed and low transmissive areas that break up connectivity and flow paths citation de dreuzy j r y meheust and g pichot 2012 influence of fracture scale heterogeneity

navier stokes flow and transport simulations using real fractures shows heavy tailing due to eddies 1 two dimensional navier stokes flow and transport simulations are conducted for a 15 cm long fracture mapped via x ray computed tomography 1 the actual fracture with irregular aperture 2 a truncated fracture where the largest aperture area is excluded from the domain 3 the truncated fracture with further thinning of other large aperture areas and 4 a fracture with uniform vertical aperture equal to the actual fracture s mean aperture are subjected to the same pressure gradient slight variations in fracture characteristics result in significantly different flow and transport behavior flux is much larger for the uniform aperture fracture compared to the actual fracture a pronounced eddy is present at the largest aperture zone of the actual fracture resulting in a power law tail absent in other cases the uniform aperture fracture has the largest effective dispersion coefficient estimated via inversion of a 1d analytical model the analytical model fit to the other cases is not as robust as in the uniform aperture case

are the alps collapsing abstract orogenic collapse is a process that transfers gravitational potential energy from regions of high potential energy to regions of lower potential energy this transfer is classically considered to be accomplished by extension in the orogenic core and by synchronous shortening in foreland regions of the orogen not all extensional features in collisional mountain belts need however reflect orogenic collapse normal faulting thrust faulting and strike slip faulting are all active in different parts of the alps today and reflect complex local responses to ongoing europe adria convergence the western alps is the only area today where extension and shortening radial to orogen trend occur synchronously and where orogenic collapse may be an important process elsewhere in the alps normal faults are oriented at a high angle to orogen trend and were primarily active in oligocene and miocene time most present day activity in the central and eastern alps is on strike slip faults that are accommodati

producing a landslide inventory map using pixel based and object oriented approaches optimized by taguchi method abstract landslides are considered one of the most important natural hazards mapping landslides and producing landslide inventory maps have received special attention from a wide range of specialists the main objective of this study was to produce landslide inventory maps using advanced pixel based ann and svm and object oriented approaches the most important challenge in this case is to determine the optimum structure of classification methods the taguchi method was to perform optimization of the structure of ann and svm and segmentation process in the object oriented classification method results showed that the taguchi method can be effectively used to cope with this problem it significantly reduces the number of classification tests we also showed that there were no significant differences existed between ann and svm approaches 2 value of 3 33 however we demonstrated that object oriented approaches significantly outperformed the pixel based classification methods z value of 5 70 in producing a landslide inventory map the accurate map produced using an object oriented approach overall accuracy of 0 90 effectively determines the shape of landslides and also efficiently shows the intensifying effects of land use changes in the occurrence of landslides

geomorphological evolution and present day processes in the dessie graben wollo ethiopia abstract this paper presents a detailed geomorphological overview of the landforms and processes characterizing the dessie basin a small graben located on the western afar margin ethiopia which is a physiographic province characterized by small closed basins and mountain ranges produced by regional extension large scale geomorphological survey and mapping of the basin allowed to point out the noteworthy morphodynamic role of the present day slope processes including numerous landslides of different typology and size these processes heavily interact with the built up area of dessie town one of the most important cities of ethiopia with ca 200 000 inhabitants which occupies a large part of the basin floor the potential incidence of landslides of different typology in the basin and their possible impact on the urban settlement are put in relation with the distribution of the different landform units which make up the basin surface

application of the discrete fracture network concept with field data possibilities of model calibration and validation the uneven flow distribution observed in a migration experiment in the stripa research mine is analyzed with a discrete fracture network model data on the measured inflow distribution and trace geometry in the experimental drift are the basic sources for estimation of the model parameters direct estimates cannot provide a unique definition of input data to the model thus different combinations of input data need to be analyzed in the network model detailed measurements of the inflow distribution in the experimental drift provided an opportunity to determine the model parameters through calibration in the network model calibration was performed on the mean inflow distribution of flow and trace geometry observed in the roof of the experimental drift the simulation results show that the model can be calibrated to produce an areal flow distribution that is consistent with the measured one the uncertainties in the input parameters are thus reduced but different combinations of input data are still possible the calibration simulations show that the length of conductive fractures per area might be used as a calibration parameter simulations based on different combinations of fracture size and density but with the same length of conductive fracture traces produced similar flow distributions the validity of the calibrated model is explored by predicting the flow into the boreholes at the experimental site the resulting inflow distributions accord well with those measured in two of the three boreholes the properties of the third borehole which differ substantially from the other two could not be explained by the simulation results

hydraulic properties of fractured rock masses with correlated fracture length and aperture permeability of fractured rocks is investigated considering the correlation between distributed fracture aperture and trace length based on a newly developed correlation equation the influence of