lithologic controls on morphology of pressure dissolution surfaces stylolites and dissolution seams in paleozoic carbonate rocks from the mideastern united states abstract examination of pressure dissolution surfaces stylolites and dissolution seams in carbonate rocks from the mideastern u s demonstrates that the morphology of these surfaces varies with rock fabric one can quantify the morphology of these pressure dissolution surfaces using four parameters thickness t of the insoluble residue defining the surface amplitude of irregularity i of the surface between vertical offsets amplitude of vertical offsets o of the surface and frequency f of vertical offsets along the surface i and o increase with t reflecting progressive development of stylolites whereas f is proportional to 1 t apparently because the physical strength of a stylolite inhibits the formation of offsets mean values of f o and t are greater in grainstones and packstones than in mudstones and wackestones and the abundance of dissolution seams relative to that of stylolites decreases through the lithologic spectrum from mudstones to grainstones these relationships suggest that development of pressure dissolution surfaces to form large stylolites depends on the heterogeneity of the limestone fabric maximum values of t and o in grainstones correlate with cement abundance t and o are low in grain rich cement poor grainstones even though grains are favored as leading or penetrating elements of stylolite columns dissolution seams surfaces with o and f near zero are found only in rocks containing fine grained dolomite t and i of those seams decrease with increasing dolomite abundance in dolomitic limestones and t and o are lower in dolostones than in limestones taken together these relationships suggest that extreme abundance of pressure resistant components such as carbonate grains and dolomite inhibit development of pressure dissolution surfaces in contrast stylolites are most extensively developed i e i t o and f are greatest in carbonate rocks in which these pressure resistant elements are mixed with less resistant components such as cement and carbonate mud the latter rocks which include packstones well cemented grainstones and slightly dolomitic limestones may undergo preferential removal from the stratigraphic record by pressure dissolution

tectonic stylolites in the undeformed cumberland plateau of southern tennessee abstract numerous tectonic stylolites i e stylolitic planes most of which are nearly vertical and strike about n30e cut through otherwise undeformed carbonates in the cumberland plateau of southeastern tennessee these stylolites confirm previous arguments that tectonic stylolites should form in flat lying strata in front of foldthrust belts the uniform trend of the teeth of the stylolites at n50w to n70w suggests that they formed as the result of alleghanian compression but the stylolites lie beyond the geographic limits of other larger scale alleghanian structures field evidence shows that the monteagle stylolites which are evenly spaced formed along pre existing fractures illustrating that even spacing is not necessarily evidence of self organization

a new stylolite classification scheme to estimate compaction and local permeability variations we modeled the geometrical roughening of bedding parallel mainly layer dominated stylolites in order to understand their structural evolution to present an advanced classification of stylolite shapes and to relate this classification to chemical compaction and permeability variations at stylolites stylolites are rough dissolution seams that develop in sedimentary basins during chemical compaction in the zechstein 2 carbonate units an important lean gas reservoir in the southern permian zechstein basin in germany stylolites influence local fluid flow mineral replacement reactions and hence the permeability of the reservoir our simulations demonstrate that layer dominated stylolites can grow in three distinct stages an initial slow nucleation phase a fast layer pinning phase and a final freezing phase if the layer is completely dissolved during growth dissolution of the pinning layer and thus destruction of the stylolite s compaction tracking capabilities is a function of the background noise in the rock and the dissolution rate of the layer itself low background noise needs a slower dissolving layer for pinning to be successful but produces flatter teeth than higher background noise we present an advanced classification based on our simulations and separate stylolites into four classes 1 rectangular layer type 2 seismogram pinning type 3 suture sharp peak type and 4 simple wave like type rectangular layer type stylolites are the most appropriate for chemical compaction estimates because they grow linearly and record most of the actual compaction up to 40 mm in the zechstein example seismogram pinning type stylolites also provide good tracking capabilities with the largest teeth tracking most of the compaction suture sharp peak type stylolites grow in a non linear fashion and thus do not record most of the actual compaction however when a non linear growth law is used the compaction estimates are similar to those making use of the rectangular layer type stylolites simple wave like stylolites are not useful for compaction estimates since their growth is highly non linear with a very low growth exponent in the case where sealing material is collected at the tooth during dissolution stylolites can act as barriers for local fluid flow as they intensify sealing capabilities of pinning layers however the development of teeth and spikes offsets and thus destroys continuous stylolite seams so that the permeability across the stylolite becomes very heterogeneous and they are no continuous barriers this behavior is best shown in rectangular layer and seismogram pinning type stylolites that develop efficient fluid barriers at teeth tips but destroy sealing capabilities of layers by offsetting them at the flank leading to a permeability anisotropy along 2 d stylolite planes suture sharp peak stylolites can create fluid barriers if they collect enough sealing material however if the collecting material does not seal or if spikes offset the sealing material the stylolite leaks we propose that our classification can be used to realistically estimate chemical compaction in reservoirs and gives an indication on how heterogeneous the permeability of stylolites can be

experimental determination of the diffusion rate of deuterated water vapor in ice and application to the stable isotopes smoothing of ice cores abstract the stable isotope records of d and 18o in ice cores show that the isotopic gradients are smoothed out with time by diffusion transport of hydrogen and oxygen atoms through solid ice is slow whereas water vapor diffusion through the interconnected porosity is much faster smoothing occurs preferentially in the upper layers of firn where the density is lowest and is responsible for the gradual alteration of the isotopic stratigraphy results for the diffusion of water vapor in ice are presented they were obtained from laboratory experiments with diffusion couples prepared using artificial snow with different d h values the samples were allowed to diffuse for about one year at a controlled temperature before being cut into thin sections and analyzed with a mass spectrometer the effects of both temperature and density were investigated the measured diffusion coefficients are fully consistent with water vapor diffusion through the ice porosity the computed values are less than the diffusion coefficient of hdo in free air and imply a tortuosity factor in the range 3 2 6 5 depending on the sample density the influence of the grain sizes on the timescale of the isotopic homogenization between the vapor phase and the ice matrix was studied we show that for grain sizes up to 1 mm in diameter solid diffusion within the grains is not a limiting factor and therefore the isotopic equilibrium between the vapor and the solid phases can be considered as immediate the diffusion model developed to compute the diffusion coefficients was further applied to investigate the real case of isotope smoothing in ice cores the smoothing rate is highly dependent on the wavelength of the isotopic signal linked to the accumulation rate and on temperature finally the model was applied to tritium deposition in antarctica from a continuous record of artificial fallout at the south pole 1954 1978 the result shows that in spite of large gradients the initial distribution underwent only limited smoothing that did not exceed 10

kinematics of stylolite formation and physics of the pressure solution process abstract a kinematical model for stylolite formation is proposed which is consistent with the geometry of all types of observed stylolites the model is based on the assumption that every surface element of an evolving stylolite behaves as a bistable system i e dissolution operates only on alternate sides of the rock bodies in contact along the stylolitic surface the proposed kinematics of stylolite production leads to the suggestion of a new physical process in some way different from the pressure solution phenomenon as it is currently conceived transfer of material from the solid state into an activated state in a supposed thin fluid film should be promoted and controlled by a spontaneous polarization of the contact region the search for conditions responsible for the setting up of this inferred process and the identification of its nature are beyond the aim of the present paper

fingerprinting stress stylolite and calcite twinning paleopiezometry revealing the complexity of progressive stress patterns during folding the case of the monte nero anticline in the apennines italy in this study we show for the first time how quantitative stress estimates can be derived by combining calcite twinning and stylolite roughness stress fingerprinting techniques in a fold and thrust belt first we present a new method that gives access to stress inversion using tectonic stylolites without access to the stylolite surface and compare results with calcite twin inversion second we use our new approach to present a high resolution deformation and stress history that affected meso cenozoic limestone strata in the monte nero anticline during its late miocene pliocene growth in the umbria marche arcuate ridge northern apennines italy in this area an extensive stylolite joint vein network developed during layer parallel shortening lps as well as during and after folding stress fingerprinting illustrates how stress in the sedimentary strata did build up prior to folding during lps the stress regime oscillated between strike slip and compressional during lps before ultimately becoming strike slip again during late stage fold tightening our case study shows that high resolution stress fingerprinting is possible and that this novel method can be used to unravel temporal relationships that relate to local variations of regional orogenic stresses beyond regional implications this study validates our approach as a new powerful toolbox to high resolution stress fingerprinting in basins and orogens combining joint and vein analysis with sedimentary and tectonic stylolite and calcite twin inversion techniques

fractal structure of stylolites abstract the recognition of fractal structure in stratigraphic systems is becoming increasingly widespread within the plethora of scale invariant sedimentary structures stylolites are one of the most visually suggestive of fractal form traces of stylolites viewed in vertical section have been studied by standard fourier spectral analysis and are found to possess spectra typical of 1 f fractional noises the power distribution is significantly shifted towards the low frequency end of the spectrum this red shifted spectrum is best modeled as a persistent fractional noise such noise spectra are those where successive positions along the data series in this case the trace of the stylolite are strongly positively correlated therefore stylolites are readily modeled as strongly persistent brownian trails regression of the noise spectrum shows the fractal dimension of the stylolite trace to be 1 346

on the use of fractal surfaces to understand seismic wave propagation in layered basalt sequences the aim of this study is to better understand how a layered basalt sequence affects the propagation of a seismic wave which has implications for sub basalt seismic imaging this is achieved by the construction of detailed realistic models of basalt sequences using data derived directly from outcrop analogues field data on the surface roughness of basaltic lava flows were captured using terrestrial laser scanning and satellite remote sensing the fractal properties of the surface roughness were derived and it can be shown that the lava flow surface is fractal over length scales up to approximately 2 km the fractal properties were then used to construct synthetic lava flow surfaces using a von karman power spectrum and the resulting surfaces were then stacked to create a synthetic lava flow sequence p wave velocity data were then added and the resulting model was used to generate synthetic seismic data the resulting stacked section shows that the ability to resolve the internal structure of the lava flows is quickly lost due to scattering and attenuation by the basalt pile a further result from generating wide angle data is that the appearance of a lower velocity layer below the basalt sequence may be caused by destructive interference within the basalt itself

isotopic diffusion in cold snow and firn molecular mixing in cold snow and firn is ordinarily controlled by vapor diffusion diffusion through or along the ice matrix is slow whereas diffusion from the air to within separate grains is comparatively rapid thus mixing occurs in the vapor phase and exchange with the local ice involves all the water molecules a quantification of these concepts is applied to the diffusion of oxygen isotopic depth profiles in southern greenland and at dome c antarctica it successfully describes the smoothing of measured profiles the smoothing rate is strongly dependent on temperature and density of the firn

anisotropic scaling of tectonic stylolites a fossilized signature of the stress field 1 vertical stylolites are pressure solution features which are considered to be caused by horizontal tectonic loading with the largest principal compressive stress being sub parallel to the earth s surface in the present study we analyze the roughness of such tectonic stylolites from two tectonic settings in southern germany and northeastern spain aiming to investigate their scaling properties with respect to the stress during formation high resolution laser profilometry was carried out on opened stylolite surfaces of nine samples these data sets were then analyzed using one and two dimensional fourier power spectral approaches we found that tectonic stylolites show two self affine scaling regimes separated by a distinct crossover length l as known for bedding parallel stylolites in addition tectonic stylolites exhibit a clear in plane scaling anisotropy that modifies l since the largest and smallest crossover lengths are oriented with the sample vertical and horizontal directions i e 2 and 3 and l is a function of the stress field during formation as analytically predicted we conclude that the scaling anisotropy of tectonic stylolites is possibly a function of the stress field knowledge of this crossover length anisotropy would enable the reconstruction of the full three dimensional stress tensor if independent constraints of the depth of formation can be obtained

the fractal geometry of some stylolites from the calcare massiccio formation italy stylolites are serrated surfaces that form by stress enhanced dissolution though their geometry and morphology reflects their formation and evolution only a few studies have attempted to quantify them here we present results indicating that stylolites in limestone of the calcare massiccio formation jurassic italy are fractal over 4 5 orders of magnitude in spatial bandwidth with an average fractal dimension obtained by spectral and scaled windowed variance analyses clustering at 1 47 some stylolites from the skene cambrian usa and tamar cenomanian israel formations are fractal over 3 orders of magnitude with fractal dimensions of 1 26 and 1 43 these values are high relative to other natural surfaces and reflect the jagged topography of the stylolites preliminary results indicate that the fractal dimension and power are constant throughout the stylolite surface and are not orientation dependent furthermore we show that stylolite contours are fractal too the grain size does not register in our analyses implying that the grain is not a cutoff between processes rather stylolite generating processes operate similarly below and above the grain size our results suggest that the geometry of these stylolites especially at long wavelengths may not be sensitive to the immediate fabric surrounding them

late cretaceous intraplate thrusting in central europe effect of africa iberia europe convergence not alpine collision a well established event of intraplate basin inversion and basement thrusting affected central europe in late cretaceous time it is widely accepted to have resulted from the collision of the alpine orogen with europe s margin at that time an early alpine orogen located on the leading edge of the adria microplate still lay far southeast of its present day position and had entered a phase of extension after a first orogenic event characterized by w to nw directed thrusting this configuration is not likely to have induced ssw nne directed thrusting and folding in the future european foreland that was still separated from the alpine wedge by a strip of oceanic lithosphere by contrast the onset of intraplate contraction coincides with an important change in relative motion between the european and african plates at ca 90 ma africa s sse directed sinistral transform motion relative to europe changed to ne directed convergence this agrees well with the timing and kinematics of intraplate thrusting in central europe structures of similar age and kinematics occurring in southern france spain and north africa suggest that the late cretaceous pulse of contraction was caused by pinching west central europe s thin lithosphere between baltica and africa only since the onset of n directed thrusting in the alps in paleocene or eocene time are the kinematics of the alps and their european foreland compatible indicating that mechanical coupling between africa europe and the adria microplate had been achieved

the influence of rock heterogeneity on the scaling properties of simulated and natural stylolites abstract stylolites are among the most prominent deformation patterns in sedimentary rocks that document localized pressure solution recent studies revealed that stylolite roughness is characterized by two distinct scaling regimes the main goal of the present study is to decipher whether this complex scaling behavior of stylolites is caused by the composition of the host rock i e heterogeneities in the material or is governed by inherent processes on respective scales namely the transition from a surface energy to an elastic energy dominated regime as theoretically predicted for this purpose we have developed a discrete numerical technique based on a lattice spring model to simulate the competition between stress strain and dissolution during stylolite roughening we varied systematically the quenched noise initially present in the material which controls the roughening we also changed the size amount and dissolution rate of the heterogeneities introduced in our model and evaluated the influence on the scaling exponents our findings demonstrate that the roughness and growth exponents are independent of the exact nature of the heterogeneities we discovered two coinciding crossover phenomena in space and time that separate length and time scales for which the roughening process is either balanced by surface or elastic energies our observations are consistent with analytical predictions and with investigations quantifying the scaling laws in the morphology of natural stylolites the findings presented here can further be used to refine volume loss compaction estimates from the finite strain pattern of stylolites

stress sensitivity of stylolite morphology abstract stylolites are rough surfaces that form by localized stress induced dissolution using a set of limestone rock samples collected at different depths from a vertical section in cirque de navacelles france we study the influence of the lithostatic stress on the stylolites morphology on the basis of a recent morphogenesis model we measured the roughness of a series of bedding parallel stylolites and show that their morphology exhibits a scaling invariance with two self affine scaling regimes separated by a crossover length l at the millimeter scale consistent with previous studies the importance of the present contribution is to estimate the stylolite formation stress from the sample position in the stratigraphic series and compare it to the crossover length l using the expected relationship l 2 we obtained a successful prediction of the crossover behavior and reasonable absolute stress magnitude estimates using relevant parameters depth of stylolite formation between 300 to 600 m with corresponding normal stress in the range of 10 18 mpa accordingly the stylolite morphology contains a signature of the stress field during formation and we thus suggest that stylolites could be used as paleo stress gauges of deformation processes in the upper crust

bedding parallel stylolites as a tool to unravel maximum burial depth in sedimentary basins application to middle jurassic carbonate reservoirs in the paris basin france in recent years stylolites which are rough dissolution surfaces commonly found in carbonates have been used for paleopiezometry estimates the stylolite roughness inversion technique srit applied on sedimentary bedding parallel stylolites bps grants access to the maximum principal vertical stress experienced by the host carbonates and thus to their maximum burial paleo depth this study reports the results of srit applied to a bps population hosted in carbonate platform reservoirs of the paris basin sub surface france middle jurassic carbonates from two well cores from the depocenter and margin of the basin for which the burial and thermal history are known based on a thermally calibrated 3 d basin model were analyzed by defining a consistency criterion and using two signal treatment methods we propose a new approach to select which bps can be reliably used to reconstruct the maximum vertical stress undergone by the host carbonates which then can be converted into maximum burial depth the study of a bps population shows that there is a control operated by the host rock texture and the stylolite morphology on the burial depth recorded especially suture and sharp peak bps are better suited to estimate the real maximum depth whereas seismogram pinning bps record preferentially intermediate depths median values of maximum depth derived from our data set 1300 and 1650 m for the margin and depocenter cores respectively are in line with maximum burial estimates provided by conventional basin modeling 1450 and 1800 m respectively thus showing that srit is a standalone robust depth gauge in sedimentary basins provided sample selection and data treatment are carried out in a rigorous and thoughtful manner

oxygen and hydrogen isotopic ratios of water in precipitation beyond paleothermometry paleoclimatologists face a dilemma no sedimentary proxy is a pure recorder of quantitative climate information yet climate modelers and policy makers increasingly seek quantitative comparisons between instrumentally documented possibly anthropogenic climate changes and those produced naturally in the past in the second edition of his influential book bradley 1999 p 6 discussed the calibration of proxy records to learn past climate changes calibration involves using modern climatic records and proxy materials to understand how and to what extent proxy materials are climate dependent it is assumed that the modern relationships observed have operated unchanged throughout the period of interest the principle of uniformitarianism in other words one relates the characteristics of sediment to climate at different places for one time or at a place for short times and then uses that relation plus characteristics of older sediments to estimate the climatic conditions that produced those sedimentary characteristics bradley 1999 then extensively discussed the difficulties in applying this methodology in a complex world with imperfect recorders nonetheless the goal of using calibrated proxies for quantitative as well as qualitative paleoclimatic reconstruction is clear a prominent recent use of calibrated paleoclimatic data is the assessment of whether the probably anthropogenic warming of the latter 20th century moved beyond the band of natural variability of the prevailing climate bradley 2000 combined recent instrumental records with several longer proxy based reconstructions of surface temperature including that of mann et al 1999 based on this composite data set bradley 2000 argued that temperatures in the late 20th century were unique in the context of the entire millennium the proxy records were primarily based on tree ring data but included isotopic and major element geochemistry of corals and occurrence of melt layers and isotopic ratios of water in ice cores however broecker 2001 questioned the basis for the reconstruction of

growth of stylolite teeth patterns depending on normal stress and finite compaction abstract stylolites are spectacular rough dissolution surfaces that are found in many rock types they are formed during a slow irreversible deformation in sedimentary rocks and therefore participate to the dissipation of tectonic stresses in the earth s upper crust despite many studies their genesis is still debated particularly the time scales of their formation and the relationship between this time and their morphology we developed a new discrete simulation technique to explore the dynamic growth of the stylolite roughness starting from an initially flat dissolution surface we demonstrate that the typical steep stylolite teeth geometry can accurately be modelled and reproduce natural patterns the growth of the roughness takes place in two successive time regimes i an initial non linear increase in roughness amplitude that follows a power law in time up to ii a critical time where the roughness amplitude saturates and stays constant we also find two different spatial scaling regimes at small spatial scales surface energy is dominant and the growth of the roughness amplitude follows a power law in time with an exponent of 0 5 and reaches an early saturation conversely at large spatial scales elastic energy is dominant and the growth follows a power law in time with an exponent of 0 8 in this elastic regime the roughness does not saturate within the given simulation time our findings show that a stylolite s roughness amplitude only captures a very small part of the actual compaction that a rock experienced moreover the memory of the compaction history may be lost once the roughness growth saturates we also show that the stylolite teeth geometry tracks the main compressive stress direction if we rotate the external main compressive stress direction the teeth are always tracking the new direction finally we present a model that explains why teeth geometries form and grow non linearly with time why they are relatively stable and why their geometry is strongly deterministic while their location is random

modeling the growth of stylolites in sedimentary rocks stylolites are ubiquitous pressure solution seams found in sedimentary rocks their morphology is shown to follow two self affine regimes analyzing the scaling properties of their height over their average direction shows that at small scale they are self affine surfaces with a hurst exponent around 1 and at large scale they follow another self affine scaling with hurst exponent around 0 5 in the present paper we show theoretically the influence of the main principal stress and the local geometry of the stylolitic interface on the dissolution reaction rate we compute how it is affected by the deviation between the principal stress axis and the local interface between the rock and the soft material in the stylolite the free energy entering in the dissolution reaction kinetics is expressed from the surface energy term and via integration from the stress perturbations due to these local misalignments the resulting model shows the interface evolution at different stress conditions in the stylolitic case i e when the main principal stress is normal to the interface two different stabilizing terms dominate at small and large scales which are linked respectively to the surface energy and to the elastic interactions integrating the presence of small scale heterogeneities related to the rock properties of the grains in the model leads to the formulation of a langevin equation predicting the dynamic evolution of the surface this equation leads to saturated surfaces obeying the two observed scaling laws analytical and numerical analysis of this surface evolution model shows that the cross over length separating both scaling regimes depends directly on the applied far field stress magnitude this method gives the basis for the development of a paleostress magnitude marker we apply the computation of this marker i e the morphological analysis on a stylolite found in the dogger limestone layer located in the neighborhood of the andra underground research laboratory at bure eastern france the results are consistent with the two scaling regimes expected and the practical determination of the major principal paleostress from the estimation of a cross over length is illustrated on this example

pressure solution features in a shallow buried limestone abstract three distinct types of pressure solution features are found in the alpena limestone devonian michigan stylolites solution seams and fitted fabric texture the style of pressure solution is different in grainstones packstones and wackestones the difference is interpreted to be the result of preferential cementation of the grainstones well cemented grainstones typically have stylolites whereas solution seams and fitted fabric texture are more common in poorly cemented grainstones packstones and wackestones pressure solution occurs at e80 percent of the lithologic transitions this is probably due to competency contrasts between adjacent units that material dissolved at pressure solution surfaces is not locally reprecipitated is indicated by porous allochems which abut against stylolites and units of abundant intergranular pressure solution fitted fabric texture which lack cement the style of pressure solution in the alpena limestone and its relationship to cementation is also observed in the tuscarora quartz arenite silurian appalachian basin

analysis of solution lineations in pebbles kinematical vs dynamical approaches abstract solution lineations in conglomerates resulting from indentation of non soluble grains of the matrix into the surface of soluble pebbles make up a morphological and genetic continuum with gradual transition between orthogonal stylolites oblique slickolites and parallel striations the distributions of incidence angles of matrix grains have been analyzed in individual pebbles in order to discern their kinematical or dynamical meaning as a general rule they fit theoretical models of flow trajectories determined by the bulk strain kinematical hypothesis in contrast they are not consistent with dynamical hypotheses based upon relationships with stress vectors in particular they do not fit the model of frictional sliding which would give rise to a sharp discontinuity between slickolites parallel to the maximum principal stress 1 and true striations parallel to the resolved shear stress therefore solution lineations all around a pebble cannot be considered as an analogue of multiple fault slip data and they should not be generally analysed by methods of stress inversion based upon bott s principle under certain conditions high pebble solubility active pressure solution processes able to accommodate the strain rate earlier cementation the solution lineations tend to be parallel to each other and to the maximum shortening compression axis they therefore assume a double kinematical and dynanical meaning and the deformation involves maximum volume reduction

high resolution 3d laser scanner measurements of a strike slip fault quantify its morphological anisotropy at all scales 1 the surface roughness of a recently exhumed strike slip fault plane has been measured by three independent 3d portable laser scanners digital elevation models of several fault surface areas from 1 m2 to 600 m2 have been measured at a resolution ranging from 5 mm to 80 mm out of plane height fluctuations are described by non gaussian distribution with exponential long range tails statistical scaling analyses show that the striated fault surface exhibits self affine scaling invariance with a small but significant directional morphological anisotropy that can be described by two scaling roughness exponents h1 0 7 in the direction of slip and h2 0 8 perpendicular to the direction of slip

the jabal akhdar dome in the oman mountains evolution of a dynamic fracture system the mesozoic succession of the jabal akhdar dome in the oman mountains hosts complex networks of fractures and veins in carbonates which are a clear example of dynamic fracture opening and sealing in a highly overpressured system the area underwent several tectonic events during the late cretaceous and cenozoic including the obduction of the samail ophiolite and hawasina nappes followed by uplift and compression due to the arabia eurasia convergence this study presents the results of an extensive tectonic survey and correlates subseismic scale structures in jabal akhdar faults fractures veins and stylolites with the main tectonic events in the northeastern arabian plate as some of the studied formations host large oil reserves in neighboring areas determining the relative timing of these events in the exhumed rocks is important to understand hydrocarbon distribution and fracture patterns in these reservoirs the formation of early veins and stylolites in the oman mountains is followed by top to the south layer parallel shearing that may be associated with the obduction of the samail and hawasina nappes this compressional tectonic event is followed by normal dip slip to oblique slip faults and veins top to the northeast layer parallel shearing which corresponds to the first stage of exhumation of the autochthonous rocks offsets these structures our new data indicate that this first phase of events is overprinted by complex strike slip networks of veins and fractures as well as by the reactivation and onset of seismic scale faults strike slip structures belong to three distinct events the first one nw se oriented compression is probably associated with the oblique collision of the indian plate against the arabian platform during the late campanian to the mid eocene the second event e w oriented compression is likely to have been formed during the late oligocene middle miocene during uplift the last event ne sw oriented compression probably took place during the miocene pliocene structures of the first two strike slip events have the same orientation as seismic scale faults observed in the subsurface of oman and abu dhabi in addition increasing vein intensity towards the top of the autochthonous formations in the oman mountains as well as the small angle between conjugate vein sets indicate that high fluid pressures that are thought to be present during strike slip deformation

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

stylolites a review abstract stylolites are ubiquitous geo patterns observed in rocks in the upper crust from geological reservoirs in sedimentary rocks to deformation zones in folds faults and shear zones these rough surfaces play a major role in the dissolution of rocks around stressed contacts the transport of dissolved material and the precipitation in surrounding pores consequently they play an active role in the evolution of rock microstructures and rheological properties in the earth s crust they are observed individually or in networks in proximity to fractures and joints and in numerous geological settings this review article deals with their geometrical and compositional characteristics and the factors leading to their genesis the main questions this review focuses on are the following how do they form how can they be used to measure strain and formation stress how do they control fluid flow in the upper crust geometrically stylolites have fractal roughness with fractal geometrical properties exhibiting typically three scaling regimes a self affine scaling with hurst exponent 1 1 0 1 at small scale up to tens or hundreds of microns another one with hurst exponent around 0 5 to 0 6 at intermediate scale up to millimeters or centimeters and in the case of sedimentary stylolites a flat scaling at large scale more complicated anisotropic scaling scaling laws depending of the direction of the profile considered is found in the case of tectonic stylolites we report models based on first principles from physical chemistry and statistical physics including a mechanical component for the free energy associated with stress concentrations and a precise tracking of the influence of grain scale heterogeneities and disorder on the resulting micro structures experimental efforts to reproduce stylolites in the laboratory are also reviewed we show that although micrometer size stylolite teeth are obtained in laboratory experiments teeth deforming numerous grains have not yet been obtained experimentally which is understandable given the very long formation time of such geometries finally the applications of stylolites as strain and stress markers to determine paleostress magnitude are reviewed we show that the scalings in stylolite heights and the crossover scale between these scalings can be used to determine the stress magnitude its scalar value perpendicular to the stylolite surface during the stylolite formation and that the stress anisotropy in the stylolite plane can be determined for the case of tectonic stylolites we also show that the crossover between medium millimetric scales and large pluricentimetric scales in the case of sedimentary stylolites provides a good marker for the total amount of dissolution which is still valid even when the largest teeth start to dissolve which leads to the loss of information since the total deformation is not anymore recorded in a single marker structure we discuss the impact of the stylolites on the evolution of the transport properties of the hosting rock and show that they promote a permeability increase parallel to the stylolites whereas their effect on the permeability transverse to the stylolite can be negligible or may reduce the permeability depending on the development of the stylolite

upper bound on stylolite roughness as indicator for amount of dissolution stylolites are rough surfaces that form by localized dissolution despite their abundance in carbonates and sandstones and their importance for fluid flow and rock deformation many fundamental issues concerning their structure and evolution are still unresolved this manuscript studies the roughening of long parallel stylolites here we report measurements of stylolite surface roughness at a scale larger than ever measured before 10 2 10 1 m measurements were performed using ground based lidar on 6 naturally exposed surfaces of 4 km long stylolites in northern israel producing a topographic map of the surfaces from which roughness characteristics were derived our results show that for length scales below 50 cm the stylolite morphology exhibits self affine behavior with a hurst exponent h 0 65 consistent with previous studies made on smaller samples the self affine behavior changes for measurements made on scales above 50 cm with h decreasing almost to zero on long length scales this observed upper bound of self affine roughness is measured here for the first time but has been previously predicted by theory ebner et al 2009b koehn et al 2007 our measurements support these theoretical models and together with them present a scenario in which the investigated stylolites evolve from preferential dissolution along an existing surface that was initially smooth and progressively roughened with time such a mechanism of stylolites growth is different from previously suggested mechanisms for other classes of stylolites which might propagate sideways from an initial defect based on the theoretical roughening model that we adopted the upper limit to fractality for this class of stylolites may be used as a measure of the amount of dissolution on stylolites indeed the amount of dissolution on the stylolites in our field site which we calculated from the upper limit to fractality is comparable to though slightly larger than our estimates of dissolution from two additional independent techniques reflecting compactive strain of 50

phosphorus cycling in marine sediments advances and challenges abstract phosphorus p is a critical macronutrient for all living cells as it provides the phosphate ester backbone of nucleic acids plays a crucial role in the transmission of chemical energy by the atp molecule and is also a structural constituent in many cell components while p cycling in the marine water column has been the subject of many studies and reviews many aspects of the sedimentary p cycling remain poorly understood this is mainly due to low p concentrations in sediments and analytical difficulties associated with isolating distinct p forms from sediment samples the aim of this review is to highlight the advances made in our understanding of p cycling in marine sediments as a result of improved instrumentation and novel approaches some of these techniques range from sediment sequential extractions sedex to spectroscopic techniques 31p nmr and innovative isotope tracer experiments stable oxygen ratios in phosphate radioactive p isotopes while our understanding of p cycling has considerably improved numerous aspects of sedimentary p cycling including the fate of organic p in sediments as a function of redox conditions organic matter content and burial depth as well as turnover rates of different sedimentary p compounds remain poorly constrained the techniques presented in this review along with yet to be utilized innovative approaches used in soil and lacustrine sediment p research will play an important role in addressing these important questions and in furthering our understanding of this critical component of the p global biogeochemical cycle

morphological analysis of stylolites for paleostress estimation in limestones surrounding the andra underground research laboratory site abstract we develop and test a methodology to infer paleostress from the morphology of stylolites within borehole cores this non destructive method is based on the analysis of the stylolite trace along the outer cylindrical surface of the cores it relies on an automatic digitisation of high resolution photographs and on the spatial fourier spectrum analysis of the stylolite traces we test and show on both synthetic and natural examples that the information from this outer cylindrical surface is equivalent to the one obtained from the destructive planar sections traditionally used the assessment of paleostress from the stylolite morphology analysis is made using a recent theoretical model which links the morphological properties to the physical processes acting during stylolite evolution this model shows that two scaling regimes are to be expected for the stylolite height power spectrum separated by a cross over length that depends on the magnitude of the paleostress during formation we develop a non linear fit method to automatically extract the cross over lengths from the digitised stylolite profiles results on cores from boreholes drilled in the surroundings of the andra underground research laboratory located at bure france show that different groups of sedimentary stylolites can be distinguished and correspond to different estimated vertical paleostress values for the oxfordian formation one group of stylolites indicates a paleostress of around 10 mpa while another group yields 15 mpa for the dogger formation two stylolites indicate a paleostress of around 10 mpa while others appear to have stopped growing at paleostresses between 30 and 22 mpa starting at an erosion phase that initiated in the late cretaceous and continues today this method has a high potential for further applications on reservoirs or other geological contexts where stylolites are present

the permeability of stylolite bearing limestone abstract stylolites are planar features that form due to intergranular pressure solution due to their planar geometry and relative abundance in limestone reservoirs their impact on regional fluid flow has attracted considerable interest we present laboratory permeability data that show that stylolites can be considered as conduits for flow in the stylolite bearing limestones measured a combination of analysis techniques shows that this is due to a zone that surrounds these stylolites that is more porous and contains larger pores than the host rock our data also show that the water permeability of a sample containing a stylolite parallel to fluid flow is typically lower than its permeability to gas explained here as a result of the expansion of minor amounts of clay found in the stylolite and that due to their microstructural similarities tectonic and sedimentary stylolites affect sample permeability similarly finally we show that the permeability anisotropy that develops in the rock mass due to the presence of sedimentary stylolites makes it appear as though the stylolites are acting as barriers to fluid flow and may explain the discrepancy between laboratory measurements and field scale observations this approach can provide estimates for the equivalent permeability and permeability anisotropy for stylolite bearing limestone reservoirs worldwide

stylolite interfaces and surrounding matrix material nature and role of heterogeneities in roughness and microstructural development rough pressure solution interfaces like stylolites are one of the most evident features of localized slow deformation in rocks of the upper crust there is a general consensus that the development of these rough structures is a result of localized stress enhanced dissolution of material along a fluid filled interface but little is known on the initiation of this roughness the aim of this article is to reveal the role of heterogeneities initially present in the host rock on roughness initiation this should give insights on whether stylolite roughness is generated by a stress induced instability or by the presence of disorder in the material i e quenched noise we use a microstructural approach based on sem ebsd analysis combined with orientation contrast oc image analysis of stylolites in limestones we found that the stylolite roughness is induced by heterogeneities in the host rock clay particles and detrital quartz grains in our case in addition close to mature stylolite interfaces matrix modifications occur which can be attributed to the compaction along the stylolite the grain size decreases by 15 25 and a pre existing shape and lattice preferred orientation spo lpo are significantly modified in the vicinity of the stylolite the results presented here imply that localized pressure solution along stylolites is not necessarily restricted to the actual interface but influences the adjacent matrix the heterogeneity data might serve as a quantitative basis for elaborate numerical models of localized compaction

reactivity of dolomitizing fluids and mg source evaluation of fault controlled dolomitization at the benicassim outcrop analogue maestrat basin e spain abstract the mechanisms responsible for the formation of huge volumes of dolomitized rocks associated with faults are not well understood we present a case study for high temperature dolomitization of an early cretaceous aptian albian ramp in benicassim maestrat basin e spain in this area seismic scale fault controlled stratabound dolostone bodies extend over several kilometres away from large scale faults this work aims at evaluating different mg sources for dolomitization estimating the reactivity of dolomitizing fluids at variable temperature and quantifying the required versus available fluid volumes to account for the benicassim dolostones field relationships stable 13 c and 18 o isotopes as well as radiogenic 87 sr 86 sr isotopes indicate that dolomitization at benicassim was produced by a high temperature fluid 80 c 13 c and 18 o isotopic compositions for dolomite vary from 0 5 to 2 9 v pdb and from 21 1 to 24 3 v smow respectively a mg source analysis reveals that the most likely dolomitizing fluid was seawater derived brine that interacted with underlying triassic red beds and the paleozoic basement geochemical models suggest that evolved seawater can be considerably more reactive than high salinity brines and the maximum reactivity occurs at about 100 c mass balance calculations indicate that interstitial fluids with high pressure and or high temperature relative to the normal geothermal gradient cannot account for the volume of dolomite at benicassim instead a pervasive fluid circulation mechanism like thermal convection is required to provide a sufficient volume of dolomitizing fluid which most likely occurred during the late cretaceous post rift stage of the maestrat basin this study illustrates the importance of fluid budget quantification to critically evaluate genetic models for dolomitization and other diagenetic processes

flow enhancement of a rough fracture we study experimentally and numerically the permeability of a rough fracture at laboratory scale when viscous forces are dominating low reynolds number the experimental setup includes a granite fracture surface 10 10 cm opened in mode i it allows a continuous opening of the fracture parallel to its mean plane the fracture roughness is measured and characterized in terms of self affine heterogeneities its isotropy is checked the departure from the cubic law is measured as a function of the aperture opening for mean separations between 4 0 and 10 3 mm and the pressure drop orientation by rotating the fracture by 90 degrees a strongly anisotropic hydraulic behavior is observed and results from the geometrical heterogeneities that exist up to the fracture macro scale

vorticity analysis in the zagros orogen shiraz area iran quantitative vorticity analyses in orogenic belts are essential for studying the kinematics of deformation and can be performed using a range of methods the combination of microstructural analysis for vorticity with other methods creates a more rigorous analysis in order to determine the degree of non coaxiality and spatial pattern of vorticity during deformation in the zagros orogenic belt a study area containing the boundary of the zagros folded belt and the zagros fold and thrust belt is selected the study area is situated in the shiraz region of e zagros in iran the kinematic vorticity analysis is carried out using 4 methods based on 1 the degree of asymmetry of the calcite c axis fabric 2 the assumption that the orientation of the long axes of calcite within an oblique stylolite foliation delineates the direction of the instantaneous stretching axis 3 the assumption that the tension gash tips determine the direction of the instantaneous stretching axis and 4 stylolite teeth determine the direction of the instantaneous stretching axis c axis data from calcite give a kinematic vorticity number between 0 68 and 0 83 and the orientation of the long axes of calcite grains yields a range between 0 5 and 0 84 stylolites provide a kinematic vorticity number between 0 5 and 0 79 and tension gashes provide a kinematic vorticity number between 0 56 and 0 81 this range of vorticity numbers confirms the contributions of both simple 33 59 and pure shear 41 67 twining of calcite also reveals that the last stage of deformation occurred at a temperature of 170 200 c spatial analysis reveals an increase in the simple shear component from the sw of the zagros folded belt to the ne of the zagros fold and thrust belt

variety of stylolites morphologies and statistical characterization of the amount of heterogeneities in the rock the surface roughness of several stylolites in limestones was measured using high resolution laser profilometry the 1d signals obtained were statistically analyzed to determine the scaling behavior and calculate a roughness exponent also called hurst exponent statistical methods based on the characterization of a single hurst exponent imply strong assumptions on the mathematical characteristics of the signal the derivative of the signal or local increments should be stationary and has finite variance the analysis of the measured stylolites shows that these properties are not always verified simultaneously the stylolite profiles show persistence and jumps and several stylolites are not regular with alternating regular and irregular portions a new statistical method is proposed here based on a non stationary but gaussian model to estimate the roughness of the profiles and quantify the heterogeneity of stylolites this statistical method is based on two parameters the local roughness h which describes the local amplitude of the stylolite and the amount of irregularities on the signal m which can be linked to the heterogeneities initially present in the rock before the stylolite formed using this technique a classification of the stylolites in two families is proposed those for which the morphology is homogeneous everywhere and those with alternating regular and irregular portions 2006 elsevier ltd all rights reserved

effect of microbial growth rate on temperature and metabolic water recorded in 18o 16o ratios of po4 in dna abstract it has been recently demonstrated that both temperature and intracellular metabolic water are recorded by the po4 moieties comprising the backbone of dna in microbial cells as well as in total microbial biomass po4 blake et al 2016 li et al 2016 temperature and intracellular water composition are reflected in the 18o 16o ratio of po4 18op in dna blake et al 2016 to determine whether the reported temperature recording by microbial dna po4 could be an artifact of variable microbial growth rate which may also vary as a function of temperature three strains of microorganisms having distinct and different growth rate patterns between 23 and 42 c pseudomonas fluorescens acinetobacter adp1 and marinobacter aquaeolei were cultured over a range of temperatures and growth rate patterns growth curve patterns for the different strains were distinct and growth rates increased with temperature however as we show here variations in 18op values of dna po4 did not correlate with changes in bacterial growth rates at a given temperature and o isotope fractionations i e partitioning of o isotopes between po4 in dna and o in water were not significantly different between strains

phosphate oxygen isotopes insights into sedimentary phosphorus cycling from the benguela upwelling system abstract marine sediments are the main sink in the oceanic phosphorus p cycle the activity of benthic microorganisms is decisive for regeneration reflux or burial of inorganic phosphate pi which has a strong impact on marine productivity recent formation of phosphorites on the continental shelf and a succession of different sedimentary environments make the benguela upwelling system a prime region for studying the role of microbes in p biogeochemistry the oxygen isotope signature of pore water phosphate 18op carries characteristic information of microbial p cycling intracellular turnover of phosphorylated biomolecules results in isotopic equilibrium with ambient water while enzymatic regeneration of pi from organic matter produces distinct offsets from equilibrium the balance of these two processes is the major control for 18op our study assesses the importance of microbial p cycling relative to regeneration of pi from organic matter from a transect across the namibian continental shelf and slope by combining pore water chemistry sulfate sulfide ferrous iron pi steady state turnover rate modeling and oxygen isotope geochemistry of pi we found 18op values in a range from 12 8 to 26 6 both in equilibrium as well as pronounced disequilibrium with water our data show a trend towards regeneration signatures disequilibrium under low mineralization activity and low pi concentrations and microbial turnover signatures equilibrium under high mineralization activity and high pi concentrations these findings are opposite to observations from water column studies where regeneration signatures were found to coincide with high mineralization activity and high pi concentrations it appears that preferential pi regeneration in marine sediments does not necessarily coincide with a disequilibrium 18op signature we propose that microbial pi uptake strategies which are controlled by pi availability are decisive for the alteration of the isotope signature this hypothesis is supported by the observation of efficient microbial pi turnover equilibrium signatures in the phosphogenic sediments of the benguela upwelling system

isotopic diffusion in polar firn implications for interpretation of seasonal climate parameters in ice core records with emphasis on central greenland if it were possible to properly extract seasonal information from ice core isotopic records paleoclimate researchers could retrieve a wealth of new information concerning the nature of climate changes and the meaning of trends observed in ice core proxy records it is widely recognized however that the diffusional smoothing of the seasonal record makes a proper extraction very difficult in this paper we examine the extent to which seasonal information specifically the amplitude and shape of the seasonal cycle is irrecoverably destroyed by diffusion in the firn first we show that isotopic diffusion firn is reasonably well understood we do this by showing that a slightly modified version of the whillans and grootes 1985 theory makes a tenable a priori prediction of the decay of seasonal isotopic amplitudes with depth at the gisp2 site though a small adjustment to one parameter significantly improves the prediction further we calculate the amplitude decay at various other ice core sites and show that these predictions compare favorably with published data from south pole and locations in southern and central greenland and the antarctic peninsula we then present numerical experiments wherein synthetic ice core records are created diffused sampled reconstituted and compared to the original these show that alter diffusive mixing in the entire fini column seasonal amplitudes can be reconstructed to within about 20 error in central greenland but that all information about sub annual signals is permanently lost there furthermore most of the error in the amplitude reconstructions is due to the unknowable variations in the sub annual signal finally we explore how these results can be applied to other locations and suggest that dye 3 has a high potential for meaningful seasonal reconstructions while siple dome has no potential at all an optimal ice core site for seasonal reconstructions has a high accumulation rate and a low temperature

stylolite controlled diagenesis of a mudstone carbonate reservoir a case study from the zechstein_2_carbonate central european basin nw germany this study was developed within the framework of dgmk german society for petroleum and coal science and technology project 718 funded by the companies exxonmobil production deutschland gmbh gdf suez e p deutschland gmbh rwe dea ag and wintershall holding gmbh the authors would like to acknowledge exxonmobil production deutschland gmbh that kindly provided core data elliot humphrey thanks the natural environment research council nerc centre for doctoral training cdt in oil gas for a phd grant egr acknowledges agaur agencia de gestio d ajuts universitaris i de recerca for a beatriu de pinos research project additional funding was provided by the generalitat de catalunya government 2017sgr 824 and the spanish government projects cgl2015 66335 c2 1 r cgl2015 69805 p and pgc2018 093903 b c22 we acknowledge theresa straub and simon gast for their assistance during core data collection we would like to thank miroslaw mirek slowakiewicz and an anonymous reviewer for their critical and constructive comments together with the editorial guidance of edoardo perri

recent and future trends in paleopiezometry in the diagenetic domain insights into the tectonic paleostress and burial depth history of fold and thrust belts and sedimentary basins paleopiezometry provides an access to the past stress magnitude key to better understand the behaviour of the earth s crust over long period of time this contribution presents a review of some paleopiezometric techniques that can be used in the diagenetic domain in fold and thrust belts and sedimentary basins calcite twinning and stylolite roughness techniques have been selected and are presented through a critical description of their methodologies along with approaches to further reconstruct the complete effective stress tensor major geological lessons learned over the past decades from published studies are summarized and discussed along with a way forward to potential breakthroughs