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Nicolas Beaudoin - One of the best experts on this subject based on the ideXlab platform.
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burial deformation history of folded rocks unraveled by fracture analysis Stylolite paleopiezometry and vein cement geochemistry a case study in the cingoli anticline umbria marche northern apennines
Geosciences, 2021Co-Authors: Aurelie Labeur, Nicolas Beaudoin, Olivier Lacombe, Laurent Emmanuel, Lorenzo Petracchini, Mathieu Daeron, Sebastian Klimowicz, Jeanpaul CallotAbstract:Unravelling the burial-deformation history of sedimentary rocks is prerequisite information to understand the regional tectonic, sedimentary, thermal, and fluid-flow evolution of foreland basins. We use a combination of microstructural analysis, Stylolites paleopiezometry, and paleofluid geochemistry to reconstruct the burial-deformation history of the Meso-Cenozoic carbonate sequence of the Cingoli Anticline (Northern Apennines, central Italy). Four major sets of mesostructures were linked to the regional deformation sequence: (i) pre-folding foreland flexure/forebulge; (ii) fold-scale layer-parallel shortening under a N045 σ1; (iii) syn-folding curvature of which the variable trend between the north and the south of the anticline is consistent with the arcuate shape of the anticline; (iv) the late stage of fold tightening. The maximum depth experienced by the strata prior to contraction, up to 1850 m, was quantified by sedimentary Stylolite paleopiezometry and projected on the reconstructed burial curve to assess the timing of the contraction. As isotope geochemistry points towards fluid precipitation at thermal equilibrium, the carbonate clumped isotope thermometry (Δ47) considered for each fracture set yields the absolute timing of the development and exhumation of the Cingoli Anticline: layer-parallel shortening occurred from ~6.3 to 5.8 Ma, followed by fold growth that lasted from ~5.8 to 3.9 Ma.
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regional scale paleofluid system across the tuscan nappe umbria marche apennine ridge northern apennines as revealed by mesostructural and isotopic analyses of Stylolite vein networks
Solid Earth, 2020Co-Authors: Nicolas Beaudoin, Daniel Koehn, Olivier Lacombe, Andrea Billi, Aurelie Labeur, Guilhem Hoareau, Adrian J Boyce, Cedric M John, Marta MarchegianoAbstract:Abstract. We report the results of a multi-proxy study that combines structural analysis of fracture-Stylolite network and isotopic characterization of calcite vein cements/fault coating. Together with new paleopiezometric and radiometric constraints on burial evolution and deformation timing, these results provide a first-order picture of the regional fluid pathways network during the main stages of contraction in the Tuscan Nappe and Umbria Marche arcuate ridge (Northern Apennines).We reconstruct four continuous steps of deformation at the scale of the belt: burial that developed sedimentary Stylolites, Apenninic-related layer parallel shortening with a contraction striking NE-SW, local extension related to folding, then a late stage of fold tightening under a contraction still striking NE-SW. In order to assess the timing and burial depth of strata at all stages, we combine a paleopiezometric tool based on inversion of the roughness of sedimentary Stylolites that constrains the range of burial depth of strata prior to layer-parallel shortening, with burial models and U-Pb absolute dating of fault coatings. In the western part of the ridge, layer-parallel shortening started in Serravalian time (~ 12 Ma), then folding started at Tortonian time (~ 8 Ma), late stage fold tightening started in early Zanclean (~ 5 Ma) and likely lasted until recent/modern extension occurred (~ 3 Ma onward). This timing provides important constraints on the temperature that expectedly prevailed in the studied strata through its history. The textural and geochemical (δ18O, δ13C, Δ47CO2 and 87Sr/86Sr) study of calcite vein cements and fault coatings reveals that most of the fluids involved in the belt during deformation are local, or flowed laterally from the same reservoir. However, the western edge of the ridge recorded pulses of eastward squeegee-type migration of hydrothermal fluids (> 140 °C), that can be related to the difference in structural style of the subsurface between the eastern Tuscan Nappe and the Umbria Marche Ridge.
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Vertical stress history and paleoburial in foreland basins unravelled by Stylolite roughness paleopiezometry: Insights from bedding-parallel Stylolites in the Bighorn Basin, Wyoming, USA.
Journal of Structural Geology, 2020Co-Authors: Nicolas Beaudoin, Daniel Koehn, Olivier Lacombe, Marie-eléonore David, Natalie Farrell, David HealyAbstract:We apply the Stylolite roughness inversion technique on sedimentary, bedding-parallel Stylolites hosted in the Paleozoic carbonates of the Bighorn and Madison formations cropping out in the Bighorn Basin, Wyoming, USA. The inversion technique applied to bedding-parallel Stylolites allows determination of the absolute magnitude of the vertical stress experienced at the time dissolution stops along the pressure-solution planes. At the basin scale, reconstructed vertical stress magnitudes range from 19 ± 2 MPa to 35 ± 4 MPa in the Bighorn Fm, and from 12 ± 2 MPa to 37 ± 4 MPa in the Madison Fm. Once converted into depth and compared with up-to-date basin models of burial and contractional history, the dataset highlights that bedding-parallel Stylolites accommodated compaction from ca. 220 Ma until ca. 90 Ma, i.e. until stress build-up related to the Sevier contraction made the maximum horizontal principal stress high enough to overcome the vertical principal stress. This study is key to illustrate how Stylolites can be used to consistently access paleoburial and to unravel both stress evolution and timing in foreland settings, and indicates that pressure-solution remains active throughout the carbonate deposition history.
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Bedding-parallel Stylolites as a tool to unravel maximum burial depth in sedimentary basins: application to Middle Jurassic carbonate reservoirs in the Paris basin
Geological Society of America Bulletin, 2019Co-Authors: Nicolas Beaudoin, M Gasparrini, M.-e David, O. Lacombe, D. KoehnAbstract: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
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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
Tectonics, 2016Co-Authors: Nicolas Beaudoin, Einat Aharonov, Daniel Koehn, Olivier Lacombe, Alexandre Lecouty, Andrea Billi, Camille ParlangeauAbstract: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.
Daniel Koehn - One of the best experts on this subject based on the ideXlab platform.
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Stylolites and Stylolite networks as primary controls on the geometry and distribution of carbonate diagenetic alterations
Marine and Petroleum Geology, 2021Co-Authors: Enrique Gomezrivas, Daniel Koehn, J D Martinmartin, Paul D Bons, Albert Griera, Anna Trave, Mariagema Llorens, Elliot HumphreyAbstract:Abstract There is ongoing debate on whether Stylolites act as barriers, conduits, or play no role in fluid transport. This problem can be tackled by examining the spatial and temporal relationships between Stylolites and other diagenetic products at multiple scales. Using the well-known Lower Cretaceous Benicassim case study area (Maestrat Basin, E. Spain), we provide new field and petrographic observations of how bedding-parallel Stylolites can influence different diagenetic processes during basin evolution. The results reveal that Stylolites can serve as baffles or inhibitors for different carbonate diagenetic reactions, and act as fronts for dolomitization, dolomite recrystallization and dolomite calcitization processes. Anastomosing Stylolites that pre-date burial dolomitization probably acted as a collective baffle for dolomitization fluids in the study area, resulting in stratabound replacement geometries at the metre-to-kilometre scale. The dolomitization front coincides with Stylolites, and can be traced along consecutive anastomosing ones. Such anastomosing Stylolites are typical of mud-dominated facies that characterize limestone-dolostone transition zones. Conversely, dolostone bodies tend to correspond to grain-dominated facies characterized by parallel (non-anastomosing) Stylolites. The same Stylolites subsequently acted as fluid flow conduits and barriers when the burial and stress conditions changed. Partly dissolved Stylolites within dolostones are found close to faults and are filled with saddle dolomite riming the Stylolite pore, and high-temperature blocky calcite cements filling the remaining porosity. The fluids responsible for these reactions were likely released from below at high pressure, causing hydraulic brecciation, and were channelised through Stylolites, which acted as fluid conduits. Stylolites are also found acting as baffles for subsequent dolomite calcitization reactions during meteoric diagenesis and occasionally appear filled with iron oxides released by calcitization. This example demonstrates how the same type of Stylolites (bedding-parallel) can act as barriers/inhibitors and/or conduits for different types of diagenetic reactions through time, and how important it is to consider their collective role when they form networks.
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regional scale paleofluid system across the tuscan nappe umbria marche apennine ridge northern apennines as revealed by mesostructural and isotopic analyses of Stylolite vein networks
Solid Earth, 2020Co-Authors: Nicolas Beaudoin, Daniel Koehn, Olivier Lacombe, Andrea Billi, Aurelie Labeur, Guilhem Hoareau, Adrian J Boyce, Cedric M John, Marta MarchegianoAbstract:Abstract. We report the results of a multi-proxy study that combines structural analysis of fracture-Stylolite network and isotopic characterization of calcite vein cements/fault coating. Together with new paleopiezometric and radiometric constraints on burial evolution and deformation timing, these results provide a first-order picture of the regional fluid pathways network during the main stages of contraction in the Tuscan Nappe and Umbria Marche arcuate ridge (Northern Apennines).We reconstruct four continuous steps of deformation at the scale of the belt: burial that developed sedimentary Stylolites, Apenninic-related layer parallel shortening with a contraction striking NE-SW, local extension related to folding, then a late stage of fold tightening under a contraction still striking NE-SW. In order to assess the timing and burial depth of strata at all stages, we combine a paleopiezometric tool based on inversion of the roughness of sedimentary Stylolites that constrains the range of burial depth of strata prior to layer-parallel shortening, with burial models and U-Pb absolute dating of fault coatings. In the western part of the ridge, layer-parallel shortening started in Serravalian time (~ 12 Ma), then folding started at Tortonian time (~ 8 Ma), late stage fold tightening started in early Zanclean (~ 5 Ma) and likely lasted until recent/modern extension occurred (~ 3 Ma onward). This timing provides important constraints on the temperature that expectedly prevailed in the studied strata through its history. The textural and geochemical (δ18O, δ13C, Δ47CO2 and 87Sr/86Sr) study of calcite vein cements and fault coatings reveals that most of the fluids involved in the belt during deformation are local, or flowed laterally from the same reservoir. However, the western edge of the ridge recorded pulses of eastward squeegee-type migration of hydrothermal fluids (> 140 °C), that can be related to the difference in structural style of the subsurface between the eastern Tuscan Nappe and the Umbria Marche Ridge.
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Vertical stress history and paleoburial in foreland basins unravelled by Stylolite roughness paleopiezometry: Insights from bedding-parallel Stylolites in the Bighorn Basin, Wyoming, USA.
Journal of Structural Geology, 2020Co-Authors: Nicolas Beaudoin, Daniel Koehn, Olivier Lacombe, Marie-eléonore David, Natalie Farrell, David HealyAbstract:We apply the Stylolite roughness inversion technique on sedimentary, bedding-parallel Stylolites hosted in the Paleozoic carbonates of the Bighorn and Madison formations cropping out in the Bighorn Basin, Wyoming, USA. The inversion technique applied to bedding-parallel Stylolites allows determination of the absolute magnitude of the vertical stress experienced at the time dissolution stops along the pressure-solution planes. At the basin scale, reconstructed vertical stress magnitudes range from 19 ± 2 MPa to 35 ± 4 MPa in the Bighorn Fm, and from 12 ± 2 MPa to 37 ± 4 MPa in the Madison Fm. Once converted into depth and compared with up-to-date basin models of burial and contractional history, the dataset highlights that bedding-parallel Stylolites accommodated compaction from ca. 220 Ma until ca. 90 Ma, i.e. until stress build-up related to the Sevier contraction made the maximum horizontal principal stress high enough to overcome the vertical principal stress. This study is key to illustrate how Stylolites can be used to consistently access paleoburial and to unravel both stress evolution and timing in foreland settings, and indicates that pressure-solution remains active throughout the carbonate deposition history.
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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
Tectonics, 2016Co-Authors: Nicolas Beaudoin, Einat Aharonov, Daniel Koehn, Olivier Lacombe, Alexandre Lecouty, Andrea Billi, Camille ParlangeauAbstract: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.
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Modelling of Stylolite geometries and stress scaling
Earth and Planetary Science Letters, 2012Co-Authors: Daniel Koehn, Francois Renard, Marcus Ebner, Renaud Toussaint, C. W. PasschierAbstract:In this contribution we present numerical simulations of Stylolite growth to decipher the effects of initial rock heterogeneity and stress on their morphology. We show that Stylolite growth in a rock with a uniform grain size produces different patterns than Stylolite growth in a rock with a bimodal grain size distribution. Strong pinning of large heterogeneities produce Stylolite structures that are dominated by pronounced teeth, whereas a uniform grain size leads to spikes and a roughness that shows variable wavelengths. We compare the simulated Stylolites with natural examples and show that the model can reproduce the real structures. In addition we show that strong pinning in the bimodal case can lead to a linear Stylolite roughness growth in contrast to the non-linear growth of Stylolites that develop from a uniform noise. In a set of 24 simulations we vary the main principle stress on the Stylolite in order to test if our model can reproduce the analytically derived stress-scaling proposed by Schmittbuhl et al. (2004). We compare the calculated stresses with the applied stresses and show that the numerical model and the analytical solution are in good agreement. Our results strengthen the hypothesis that Stylolites can be used as strain and stress gauges to estimate not only the orientation of paleo-stresses, but also their absolute values of formation stresses and amounts of compaction.
Olivier Lacombe - One of the best experts on this subject based on the ideXlab platform.
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burial deformation history of folded rocks unraveled by fracture analysis Stylolite paleopiezometry and vein cement geochemistry a case study in the cingoli anticline umbria marche northern apennines
Geosciences, 2021Co-Authors: Aurelie Labeur, Nicolas Beaudoin, Olivier Lacombe, Laurent Emmanuel, Lorenzo Petracchini, Mathieu Daeron, Sebastian Klimowicz, Jeanpaul CallotAbstract:Unravelling the burial-deformation history of sedimentary rocks is prerequisite information to understand the regional tectonic, sedimentary, thermal, and fluid-flow evolution of foreland basins. We use a combination of microstructural analysis, Stylolites paleopiezometry, and paleofluid geochemistry to reconstruct the burial-deformation history of the Meso-Cenozoic carbonate sequence of the Cingoli Anticline (Northern Apennines, central Italy). Four major sets of mesostructures were linked to the regional deformation sequence: (i) pre-folding foreland flexure/forebulge; (ii) fold-scale layer-parallel shortening under a N045 σ1; (iii) syn-folding curvature of which the variable trend between the north and the south of the anticline is consistent with the arcuate shape of the anticline; (iv) the late stage of fold tightening. The maximum depth experienced by the strata prior to contraction, up to 1850 m, was quantified by sedimentary Stylolite paleopiezometry and projected on the reconstructed burial curve to assess the timing of the contraction. As isotope geochemistry points towards fluid precipitation at thermal equilibrium, the carbonate clumped isotope thermometry (Δ47) considered for each fracture set yields the absolute timing of the development and exhumation of the Cingoli Anticline: layer-parallel shortening occurred from ~6.3 to 5.8 Ma, followed by fold growth that lasted from ~5.8 to 3.9 Ma.
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regional scale paleofluid system across the tuscan nappe umbria marche apennine ridge northern apennines as revealed by mesostructural and isotopic analyses of Stylolite vein networks
Solid Earth, 2020Co-Authors: Nicolas Beaudoin, Daniel Koehn, Olivier Lacombe, Andrea Billi, Aurelie Labeur, Guilhem Hoareau, Adrian J Boyce, Cedric M John, Marta MarchegianoAbstract:Abstract. We report the results of a multi-proxy study that combines structural analysis of fracture-Stylolite network and isotopic characterization of calcite vein cements/fault coating. Together with new paleopiezometric and radiometric constraints on burial evolution and deformation timing, these results provide a first-order picture of the regional fluid pathways network during the main stages of contraction in the Tuscan Nappe and Umbria Marche arcuate ridge (Northern Apennines).We reconstruct four continuous steps of deformation at the scale of the belt: burial that developed sedimentary Stylolites, Apenninic-related layer parallel shortening with a contraction striking NE-SW, local extension related to folding, then a late stage of fold tightening under a contraction still striking NE-SW. In order to assess the timing and burial depth of strata at all stages, we combine a paleopiezometric tool based on inversion of the roughness of sedimentary Stylolites that constrains the range of burial depth of strata prior to layer-parallel shortening, with burial models and U-Pb absolute dating of fault coatings. In the western part of the ridge, layer-parallel shortening started in Serravalian time (~ 12 Ma), then folding started at Tortonian time (~ 8 Ma), late stage fold tightening started in early Zanclean (~ 5 Ma) and likely lasted until recent/modern extension occurred (~ 3 Ma onward). This timing provides important constraints on the temperature that expectedly prevailed in the studied strata through its history. The textural and geochemical (δ18O, δ13C, Δ47CO2 and 87Sr/86Sr) study of calcite vein cements and fault coatings reveals that most of the fluids involved in the belt during deformation are local, or flowed laterally from the same reservoir. However, the western edge of the ridge recorded pulses of eastward squeegee-type migration of hydrothermal fluids (> 140 °C), that can be related to the difference in structural style of the subsurface between the eastern Tuscan Nappe and the Umbria Marche Ridge.
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Vertical stress history and paleoburial in foreland basins unravelled by Stylolite roughness paleopiezometry: Insights from bedding-parallel Stylolites in the Bighorn Basin, Wyoming, USA.
Journal of Structural Geology, 2020Co-Authors: Nicolas Beaudoin, Daniel Koehn, Olivier Lacombe, Marie-eléonore David, Natalie Farrell, David HealyAbstract:We apply the Stylolite roughness inversion technique on sedimentary, bedding-parallel Stylolites hosted in the Paleozoic carbonates of the Bighorn and Madison formations cropping out in the Bighorn Basin, Wyoming, USA. The inversion technique applied to bedding-parallel Stylolites allows determination of the absolute magnitude of the vertical stress experienced at the time dissolution stops along the pressure-solution planes. At the basin scale, reconstructed vertical stress magnitudes range from 19 ± 2 MPa to 35 ± 4 MPa in the Bighorn Fm, and from 12 ± 2 MPa to 37 ± 4 MPa in the Madison Fm. Once converted into depth and compared with up-to-date basin models of burial and contractional history, the dataset highlights that bedding-parallel Stylolites accommodated compaction from ca. 220 Ma until ca. 90 Ma, i.e. until stress build-up related to the Sevier contraction made the maximum horizontal principal stress high enough to overcome the vertical principal stress. This study is key to illustrate how Stylolites can be used to consistently access paleoburial and to unravel both stress evolution and timing in foreland settings, and indicates that pressure-solution remains active throughout the carbonate deposition history.
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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
Tectonics, 2016Co-Authors: Nicolas Beaudoin, Einat Aharonov, Daniel Koehn, Olivier Lacombe, Alexandre Lecouty, Andrea Billi, Camille ParlangeauAbstract: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.
Renaud Toussaint - One of the best experts on this subject based on the ideXlab platform.
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Stylolites: A review
Journal of Structural Geology, 2018Co-Authors: Renaud Toussaint, E. Aharonov, D. Koehn, P. Gratier, M. Ebner, P. Baud, A. Rolland, F. RenardAbstract:Highlights:. Stylolite formation depends on rock composition and structure, stress and fluids.. Stylolite geometry, fractal and self-affine properties, network structure, are investigated.. The experiments and physics-based numerical models for their formation are reviewed.. Stylolites can be used as markers of strain, paleostress orientation and magnitude.. Stylolites impact transport properties, as function of maturity and flow direction.AbstractStylolites 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.
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sedimentary Stylolite networks and connectivity in limestone large scale field observations and implications for structure evolution
Journal of Structural Geology, 2014Co-Authors: Leehee Laronne Benitzhak, Einat Aharonov, Ziv Karcz, Maor Kaduri, Renaud ToussaintAbstract:Stylolites are rough surfaces, formed by localized rock dissolution, and prevalent in carbonates and other sedimentary rocks. Their impact on porosity and permeability, and capacity to accommodate compactive strain, are well documented. This paper presents a meso-scale field study on sedimentary Stylolites in carbonates, characterizing large-scale distributions of Stylolites, including measurements conducted on longer than kilometer-long Stylolites. Our field study suggests that on large-scales connections between Stylolites become important. Since connectivity, and also lack of connectivity, are expected to play a significant role in strain accommodation and hydraulic rock properties, we suggest that large-scale analysis may require a new characterization scheme for "Stylolites populations", based on their connectivity. We therefore divide sedimentary Stylolite populations into three end-member types, which are correlated with the three possibilities for percolation of such systems: isolated Stylolites (with zero percolation/connectivity), long-parallel Stylolites (with 2-dimensional percolation/connectivity), and interconnected Stylolite networks (with 3-dimensional percolation/connectivity). New statistical parameters and measures are devised and used to quantitatively characterize the different population types. Schematic mechanistic models are then offered to explain the evolution of the three end-member connectivity-classes. In addition we discuss the effect on fluid flow of the different population types.
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Morphological analysis of Stylolites for paleostress estimation in limestones surrounding the Andra Underground Research Laboratory site
International Journal of Rock Mechanics and Mining Sciences, 2013Co-Authors: Alexandra Rolland, Renaud Toussaint, Patrick Baud, Nathalie Conil, Philippe LandreinAbstract: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 digitization 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 digitized 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 indicate 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.
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Modelling of Stylolite geometries and stress scaling
Earth and Planetary Science Letters, 2012Co-Authors: Daniel Koehn, Francois Renard, Marcus Ebner, Renaud Toussaint, C. W. PasschierAbstract:In this contribution we present numerical simulations of Stylolite growth to decipher the effects of initial rock heterogeneity and stress on their morphology. We show that Stylolite growth in a rock with a uniform grain size produces different patterns than Stylolite growth in a rock with a bimodal grain size distribution. Strong pinning of large heterogeneities produce Stylolite structures that are dominated by pronounced teeth, whereas a uniform grain size leads to spikes and a roughness that shows variable wavelengths. We compare the simulated Stylolites with natural examples and show that the model can reproduce the real structures. In addition we show that strong pinning in the bimodal case can lead to a linear Stylolite roughness growth in contrast to the non-linear growth of Stylolites that develop from a uniform noise. In a set of 24 simulations we vary the main principle stress on the Stylolite in order to test if our model can reproduce the analytically derived stress-scaling proposed by Schmittbuhl et al. (2004). We compare the calculated stresses with the applied stresses and show that the numerical model and the analytical solution are in good agreement. Our results strengthen the hypothesis that Stylolites can be used as strain and stress gauges to estimate not only the orientation of paleo-stresses, but also their absolute values of formation stresses and amounts of compaction.
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upper bound on Stylolite roughness as indicator for amount of dissolution
Earth and Planetary Science Letters, 2012Co-Authors: Einat Aharonov, Renaud Toussaint, Leehee Laronne Benitzhak, Amir SagyAbstract: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%.
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The permeability of Stylolite-bearing limestone
'Elsevier BV', 2018Co-Authors: Heap Michael, Baud Patrick, Reuschle Thierry, Renard François, Iezzi GianlucaAbstract:International audienceStylolites 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
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Impact of Stylolites on the mechanical strength of limestone
'Elsevier BV', 2016Co-Authors: Baud Patrick, Rolland Alexandra, Heap Michael, Xu Tao, Nicolé Marion, Ferrand Thomas, Reuschle Thierry, Toussaint Renaud, Conil NathalieAbstract:We performed a series of uniaxial compression tests on samples of microporous carbonates from the Paris Basin (Bure, France). Sedimentary Stylolites are pervasive in these formations. We show that the porosity in the vicinity of the Stylolites is always higher than that of the host rock. As a result, our new mechanical data reveal that samples with a Stylolite are always measurably weaker with respect to the adjacent Stylolite-free material. However, when present, the orientation of the Stylolite (with respect to the direction of loading) does not result in any mechanical anisotropy. Numerical simulations using a 2D finite element code suggest that the weakening induced by the presence of a Stylolite is mostly due to the higher porosity and the higher level of heterogeneity in and around the Stylolite, while the absence of mechanical anisotropy is due to the roughness of the Stylolite. While the presence of Stylolites weakens carbonate rocks, Stylolites only act as planes of weakness when their thickness exceeds a certain threshold (about 5 mm)
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Stylolites in limestones: Barriers to fluid flow?
'Geological Society of America', 2014Co-Authors: Heap Michael, Baud Patrick, Reuschle Thierry, Meredith PhilipAbstract:International audienceStylolites--products of intergranular pressure-solution--are laterally extensive, planar features. They are a common strain localization feature in sedimentary rocks. Their potential impact on regional fluid flow has interested geoscientists for almost a century. Prevalent views are that they act as permeability barriers, although laboratory studies are extremely rare. Here we report on a systematic laboratory study of the influence of Stylolites on permeability in limestone. Our data demonstrate that, contrary to conventional wisdom, the studied Stylolites do not act as barriers to fluid flow. In detail, when a Stylolite occurs perpendicular to the direction of flow, the permeability simply follows the same power law permeability-porosity trend as the Stylolite-free material. We show, using a combination of high-resolution (4 µm) X-ray computed tomography, optical microscopy, and chemical analyses, that the Stylolites of this study are not only perforated layers constructed from numerous discontinuous pressure solution seams, but comprise minerals of similar or lower density to the host rock. The Stylolites are not continuous high-density layers. Our data affirm that Stylolites may not impact regional fluid flow as much as previously anticipated
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Morphological analysis of Stylolites for paleostress estimation in limestones surrounding the Andra Underground Research Laboratory site
'Elsevier BV', 2013Co-Authors: Rolland Alexandra, Baud Patrick, Toussaint Renaud, Conil Nathalie, Landrein PhilippeAbstract: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 digitization 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 digitized 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 indicate 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.Comment: International Journal of Rock Mechanics and Mining Sciences (2013) online firs
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Rhéologie, localisation de la déformation et histoire des contraintes dans les calcaires du site de Bure
Université de Strasbourg Strasbourg, 2013Co-Authors: Rolland Alexandra, Baud PatrickAbstract:Un Laboratoire de Recherche Souterrain (URL) a été construit en 2000 par l Agence Nationale pour la Gestion des Déchets Radioactifs (Andra) dans le but d étudier la faisabilité d un site de stockage de déchets radioactifs dans une formation d argile à Bure dans la Meuse. L horizon choisi pour le laboratoire est une couche de 135 m d épaisseur de roches argileuses du Callovo-Oxfordien (COX) qui s étend de 420 à 555 m sous le Laboratoire du site de Bure. La couche d argilites est entourée de bancs calcaires de l Oxfordien et du Dogger (respectivement, 161,2 à 164,7 Ma et 164,7 à 175,6 Ma). De nombreux Stylolites ont été trouvés dans ces horizons calcaires. Le but de ce travail était d étudier la rhéologie des horizons contenant ces Stylolites et d utiliser ces structures comme marqueurs de contraintes dans la zone proche de l URL. Pour ce travail, un grand nombre d échantillons avec et sans Stylolites ont été prélevés dans de nombreuses carottes provenant de plusieurs forages dans les formations de l Oxfordien et du Dogger. Les mesures pétrophysiques et les études de microstructure mises en œuvre sur ces calcaires révèlent la structure microporeuse de toutes ces roches, de porosités comprises entre 4 et 18 %. La présence des Stylolites s accompagne d une augmentation localisée de la porosité et de variations sensibles de certaines propriétés physiques ainsi que de la résistance mécanique des calcaires. Un modèle reliant une longueur caractéristique associée à la morphologie d un Stylolite et la contrainte associée au développement de cette structure est présenté. Pour utiliser ce modèle, nous avons développé une méthode pour analyser la morphologie de Stylolites à partir du calcul du spectre de puissance de Fourier en prenant en compte toutes les difficultés liées à la géométrie de carottes provenant de forages. Cette méthode est appliquée pour des Stylolites échantillonnés à des profondeurs différentes, de 158 m à 800 m dans les formations calcaires de l Oxfordien et du Dogger. Nous avons analysé des profils 1D extraits des contours des carottes. En accord avec les prédictions théoriques, nous avons observé sur les spectres résultants des analyses, deux régimes différents pour les petites et grandes échelles séparés par une longueur de coupure. Nous avons ensuite déterminé les paléocontraintes associées aux longueurs de coupures trouvées et aux modules élastiques des roches. En considérant l évolution géologique des formations du site de Bure, nous discutons pour finir les variations avec la profondeur des paléocontraintes estimées pour les Stylolites des formations de l Oxfordien et du Dogger.In order to demonstrate the feasibility of a radioactive waste repository (HLW) in clay-stone formation, the french national radioactive waste management agency (Andra) started in 2000 to build an underground research laboratory (URL) at Bure in the south of the Meuse district. The target horizon for the laboratory is a 135 m thick layer of argillaceous rock (Callovo-Oxfordian claystone) that lies between about 420 and 555 meters below the surface at the URL site. The argillite layer (COX) is surrounded by limestones from the Dogger and the Oxfordian ages (respectively 164,7 to 175,6 Ma and 161,2 to 164,7 Ma). Numerous Stylolites were found in these limestones. The aim of this work is to study the rheology of these Stylolite-riched horizons and the Stylolites as stress gauges in the Dogger and Oxfordian formations. In this work, a wide range of samples with and without Stylolites were sampled in the Dogger and Oxfordian formations. Petrophysical measurements and microstructural studies showed that all these limestones have a microporous structure. We showed that the Stylolites induced significant variations in some physical properties and in the rock strength. Based on an analytical model, presented here in details, linking a characteristic length associated to the Stylolite morphology and the stress associated to the development of that Stylolite, a method for the morphology analysis of Stylolites is developed, using a Fourier power spectrum technique, by taking into account all the difficulties linked to the use of cores from deep boreholes. We apply this method on Stylolites at various depths, starting from the Oxfordian formation at a depth of 158 meters to the Dogger formation at a depth of 800 meters. No Stylolites are found in the intermediate Callovo-Oxfordian claystone formation. We analyze 1D profiles taken on the outer part of the cores. In agreement with theoretical predictions, we always observe two regimes for small and large scales separated by a cross-over length. We, then, infer the corresponding paleostresses from this cross-over length and from the elastic properties of the rocks. Considering the geological evolution of the area, we discuss the variation with depth of the inferred paleostresses in the Dogger and Oxfordian formations.STRASBOURG-Bib.electronique 063 (674829902) / SudocSudocFranceF
