Jeroen Kenter - Academia.edu (original) (raw)

Papers by Jeroen Kenter

Research paper thumbnail of UAV-Based 3d Outcrop Analog Models for Oil and Gas Exploration and Production

IGARSS 2019 - 2019 IEEE International Geoscience and Remote Sensing Symposium, 2019

Outcrop analog studies are commonly used in the oil and gas industry to better constrain subsurfa... more Outcrop analog studies are commonly used in the oil and gas industry to better constrain subsurface geometries and facies heterogeneity distribution. Coupled with field data, drone-based photogrammetric models bring key value to outcrop analog studies for reservoir characterization. In the scope of referencing world class outcrop analogs for hydrocarbon exploration and production, we launched a series of 3D acquisitions on several outcrop analogs in different sedimentological settings. The paper describes the workflow steps applied on a specific case study, from the acquisition of photogrammetric data to geological interpretation. The study area is the Aptian carbonate platform to basin transition of the Maestrat Basin (Spain), which is considered as a world class reference analog of the productive Shuaiba Formation in the Middle East.

Research paper thumbnail of Quantitative mapping of dolomitization using close-range hyperspectral imaging: Kimmeridgian carbonate ramp, Alacón, NE Spain

Geosphere, 2022

Geological models from outcrop analogues are often utilized as a guide, or soft constraint, for d... more Geological models from outcrop analogues are often utilized as a guide, or soft constraint, for distributing reservoir properties in subsurface models. In carbonate outcrops, combined sequence stratigraphic, sedimentological, and petrographic studies constrain the heterogeneity of geobodies and diagenetic processes, including dolomitization, at multiple scales. High-resolution digital outcrop modeling further aids geometric mapping, geobody definition, and statistical analysis, though its usefulness for detailed mineralogical and lithological mapping is limited. Hyperspectral imaging offers enhanced spectral resolution for mapping subtle mineralogical differences. In both outcrops and subsurface, differences in carbonate composition can provide key information for distributing porosity and permeability, yet this mapping is highly challenging in field studies due to access difficulties, visible material differences, and sampling resolution. Spectral analysis of limestone–dolomite rat...

Research paper thumbnail of Introduction to special section: Geophysical imaging and interpretation of outcrops

Research paper thumbnail of Pennsylvanian high-relief microbial boundstone-dominated carbonate platform margins (Sierra del Cuera, Asturias, Spain)

Field guides to exceptionally exposed carbonate outcrops, Dec 31, 2021

Research paper thumbnail of Mineralogical Mapping with Accurately Corrected Shortwave Infrared Hyperspectral Data Acquired Obliquely from UAVs

Remote. Sens., 2022

While uncrewed aerial vehicles are routinely used as platforms for hyperspectral sensors, their a... more While uncrewed aerial vehicles are routinely used as platforms for hyperspectral sensors, their application is mostly confined to nadir imaging orientations. Oblique hyperspectral imaging has been impeded by the absence of robust registration and correction protocols, which are essential to extract accurate information. These corrections are especially important for detecting the typically small spectral features produced by minerals, and for infrared data acquired using pushbroom sensors. The complex movements of unstable platforms (such as UAVs) require rigorous geometric and radiometric corrections, especially in the rugged terrain often encountered for geological applications. In this contribution we propose a novel correction methodology, and associated toolbox, dedicated to the accurate production of hyperspectral data acquired by UAVs, without any restriction concerning view angles or target geometry. We make these codes freely available to the community, and thus hope to tri...

Research paper thumbnail of Case History Acoustic properties of carbonates: Effects of rock texture

More than 250 plugs from outcrops and three nearby boreholes in an undisturbed reef of Miocene ͑T... more More than 250 plugs from outcrops and three nearby boreholes in an undisturbed reef of Miocene ͑Tortonian͒ age were quantitatively analyzed for texture, mineralogy, and acoustic properties. We measured the P-and S-waves of carbonate rocks under dry ͑humidified͒ and brine-saturated conditions at 10 MPa effective pressure with an ultrasonic pulse transmission technique ͑1 MHz͒. The data set was compared with an extensive database of petrophysical measurements of a variety of rock types encountered in carbonate sedimentary sequences. Two major textural groups were distinguished on the basis of trends in plots of compressional-wave velocity versus Poisson's ratio ͑a specific ratio of P-wave over S-wave velocity͒. In granular rocks, the framework of depositional grains is the main medium for acoustic-wave propagation; in crystalline rocks, this medium is provided by a framework of interlocking crystals formed during diagenesis. Rock textures are connected to primary depositional parameters and a diagenetic overprint through the specific effects on Poisson's ratio. Calculating acoustic velocities using Gassmann fluid substitution modeling approximates measured saturated velocities for 55% of the samples ͑3% error tolerance͒; however, it shows considerable errors because shear modulus changes with saturation. Introducing brine into the pore space may decrease the shear modulus of the rock by approximately 1.4 GPa or, alternatively, increase it by approximately 1.4 GPa. This change in shear modulus is coupled with the texture of the rock. In granular carbonates, the shear modulus decreases; in crystalline and cemented carbonates, it increases with saturation. The results demonstrate the intimate relationship between elastic behavior and the depositional and diagenetic properties of carbonate sedimentary rocks. The results potentially allow the direct extraction of granular and crystalline rock texture from acoustic data alone and may help predict rock types from seismic data and in wells.

Research paper thumbnail of Strategies for Modeling Depositional Heterogeneity of Carbonate Ramps UsingOutcrop Analogs and Multiple Point Statistics

Research paper thumbnail of Slope angle and basin depth of the Triassic platform-basin transition at the Gosaukamm, Austria

Austrian Journal of Earth Sciences, 2009

Large-scale, steep and straight bedding is present in exposures of the Triassic Dachstein carbona... more Large-scale, steep and straight bedding is present in exposures of the Triassic Dachstein carbonate platform slope at the Gosaukamm, Austria. Field observations revealed high and planar clinoforms with declivities of ca. 30° and bedding thicknesses varying between 1 and 100 m. The sediment is mainly composed of poorly sorted mixtures of carbonate sand and gravel, almost devoid of mud. Measurements of geopetal fabrics and the flat stratigraphic boundary of clinoforms and underlying cherty basin limestones (Gosauseekalk) both indicate that the clinoforms are dipping more or less at their original depositional angle of 30°. Tracing of clinoforms yields a minimum estimate of the platform-basin relief of 300 m, while depositional relief exceeding 500 m is most likely. Even the most conservative estimate of water depth puts the basin floor below the neritic realm, supporting the deep-basin model of the Hallstatt zones. However, moderate uplift of the basins relative to the platforms durin...

Research paper thumbnail of Oligocene and Miocene Global Spatial Trends of Shallow-Marine Carbonate Architecture

The Journal of Geology

The present study provides the baseline status of the spatial distribution of carbonate platforms... more The present study provides the baseline status of the spatial distribution of carbonate platforms for the Oligo-Miocene interval. The resulting global trend quantitatively shows the decreasing growth potential of shallow-marine carbonates toward higher paleolatitudes. Such a global trend provides a geological context and external constraints for local and regional interpretations of specific case studies. Furthermore, the direct relationship between carbonate accumulations and paleoclimatic regions shows that, using such a qualitative and quantitative data set for calibration, paleoceanographic models could be utilized for the prediction of the global distribution of carbonate stratigraphic architecture.

Research paper thumbnail of Joint Systems and Fault-Controlled Hydraulic Fracturing in Outcrops – Impact on Precitions of Reservoir Properties

1st EAGE North African/Mediterranean Petroleum & Geosciences Conference & Exhibition

Research paper thumbnail of Microbial boundstone dominated carbonate slope (Upper Carboniferous, N Spain): Microfacies, lithofacies distribution and stratal geometry

Facies

The Carboniferous, particularly during the Serpukhovian and Bashkirian time, was a period of scar... more The Carboniferous, particularly during the Serpukhovian and Bashkirian time, was a period of scarce shallow-water calcimicrobial-microbialite reef growth. Organic frameworks developed on high-rising platforms are, however, recorded in the Precaspian Basin subsurface, ...

Research paper thumbnail of Synthetic Seismograms at Site 866: Origin of Reflections and Implications for Recognizing the Limestone-Basalt Transition in Cretaceous Mid-Pacific Guyots

Proceedings of the Ocean Drilling Program, 143 Scientific Results

Synthetic seismograms at Hole 866 were derived from sonic velocity and neutron density logs and c... more Synthetic seismograms at Hole 866 were derived from sonic velocity and neutron density logs and compared to the lithology and seismic reflection data. In addition, logs of neutron density, neutron porosity, resistivity, gamma-ray, and discrete measurements were used to generate pseudo-velocity logs as input for synthetic seismograms to evaluate their potential as proxy for sonic velocity. The experiment has several implications for the study of seismic reflection profiles over Cretaceous Mid-Pacific guyots.

Research paper thumbnail of Acoustic properties from logs and discrete measurements (Sites 966 and 967) on Eratosthenes Seamount: controls and ground truth

Proceedings of the Ocean Drilling Program, 160 Scientific Results

Acoustic properties (P-wave velocities, densities, and porosities) and insoluble residues were me... more Acoustic properties (P-wave velocities, densities, and porosities) and insoluble residues were measured at in situ pressures in 68 core plugs taken from cores recovered at Ocean Drilling Project Sites 966 and 967 and compared with wireline logging data. Study of the parameters that control the acoustic properties and the quality of the logging data reveals: (1) velocity-porosity and velocity-density relationships within the discrete data follow the general trend of the general empirical equation but are offset with respect to it. Insoluble residue and dolomite content are the primary controls on the acoustic velocities of the core plugs, whereas lithologic facies has no or a minor effect; and (2) velocity-porosity and velocity-density relationships in the logging data show considerable deviation and trends that cross those from the general relationships that are believed to approximate fundamental physical principles. Calculated uncertainties in the laboratory measurements are at least one order of magnitude smaller than the difference between laboratory measurements and those from the wireline logs in several intervals. As a consequence, we believe that the downhole wireline measurements are unreliable in large intervals at both sites. Possible causes of the unreliability are poor hole conditions, upscaling effects, and consequent difficulties in making realistic corrections of the raw log data. The wireline logs were found to be of such poor quality that they are untrustworthy sources of acoustic parameters for making synthetic seismograms. This study clearly indicates that logging data should be carefully evaluated and calibrated with petrophysical relationships from literature and from discrete measurements before interpretation or use as input for synthetic seismograms when hole conditions are poor.

Research paper thumbnail of Carbonate petrophysical rock typing: integrating geological attributes and petrophysical properties while linking with dynamic behaviour

Geological Society, London, Special Publications, 2014

Research paper thumbnail of An alternative model for positive shifts in shallow-marine carbonate ��13C and ��18O: An alternative model for carbon and oxygen isotope shifts

Sedimentology, 2003

Positive shifts in global seawater d 13 C DIC are related to changes in the ratio of organic rela... more Positive shifts in global seawater d 13 C DIC are related to changes in the ratio of organic relative to inorganic carbon burial in oceanic basins, whereas factors such as climatic cooling and the accumulation of polar ice are known to cause positive shifts in d 18 O. Here, an alternative model is proposed for the formation of local positive isotope shifts in shallow-marine settings. The model involves geochemically altered platform-top water masses and the effects of early meteoric diagenesis on carbonate isotopic composition. Both mechanisms are active on modern (sub)tropical carbonate platforms and result in low carbonate d 13 C and d 18 O relative to typical oceanic values. During high-amplitude transgressive events, the impact of isotopically light meteoric fluids on the carbonate geochemistry is much reduced, and 13 C-depleted platform-top water mixes with open oceanic water masses having higher isotope values. Both factors are recorded as a transient increase in carbonate 13 C and 18 O relative to low background values. These processes must be taken into consideration when interpreting the geochemical record of ancient epeiric seas.

Research paper thumbnail of A comparison of shear strength in calcareous and siliciclastic marine sediments

Marine Geology, Jul 1, 1989

... In: KR Demars and RC Chancy (Editors), Geotechnical Properties. ... Bearing strength and othe... more ... In: KR Demars and RC Chancy (Editors), Geotechnical Properties. ... Bearing strength and other physical properties of some shallow and deep-sea sediments from the North Pacific. Geol. Soc. Am. ... Shear strength and stability of continental slope deposits, Western Gulf of Mexico. ...

Research paper thumbnail of Sedimentation on a Lower Jurassic carbonate platform flank: geometry, sediment fabric and related depositional structures (Djebel Bou Dahar, High Atlas, Morocco)

Sedimentary Geology, 1991

At ca. 50 m below the platform margin, coral-algal patch reefs and ooid sand shoals grade into th... more At ca. 50 m below the platform margin, coral-algal patch reefs and ooid sand shoals grade into the depositional slope. The straight upper slope, showing discontinuous bedding at angles up to 29°, extends down to ca. 250 m and consists mainly of poorly sorted mixtures of sand ...

Research paper thumbnail of Facies belts of a Carboniferous carbonate platform (San Antolín-La Huelga section, NE Cantabrian Zone)

Trabajos De Geologia, 2008

Research paper thumbnail of Non-Actualistic Carbonate Deposystems: Revi sing The Carbonate Factory-Depth Paradigm

Non-actualistic (e.g., deviating from depositional models developed for recent deposystems) carbo... more Non-actualistic (e.g., deviating from depositional models developed for recent deposystems) carbonate platforms are not the exception in the geologic record because of the wide range of biological and environmental factors controlling facies character and architecture.

Research paper thumbnail of Anatomy and Lithofacies of an Intact and Seismic-Scale Carboniferous Carbonate Platform (Asturias, NW Spain): Analogs of Hydrocarbon Reservoirs in the Pricaspian Basin (Kazakhstan)

Research paper thumbnail of UAV-Based 3d Outcrop Analog Models for Oil and Gas Exploration and Production

IGARSS 2019 - 2019 IEEE International Geoscience and Remote Sensing Symposium, 2019

Outcrop analog studies are commonly used in the oil and gas industry to better constrain subsurfa... more Outcrop analog studies are commonly used in the oil and gas industry to better constrain subsurface geometries and facies heterogeneity distribution. Coupled with field data, drone-based photogrammetric models bring key value to outcrop analog studies for reservoir characterization. In the scope of referencing world class outcrop analogs for hydrocarbon exploration and production, we launched a series of 3D acquisitions on several outcrop analogs in different sedimentological settings. The paper describes the workflow steps applied on a specific case study, from the acquisition of photogrammetric data to geological interpretation. The study area is the Aptian carbonate platform to basin transition of the Maestrat Basin (Spain), which is considered as a world class reference analog of the productive Shuaiba Formation in the Middle East.

Research paper thumbnail of Quantitative mapping of dolomitization using close-range hyperspectral imaging: Kimmeridgian carbonate ramp, Alacón, NE Spain

Geosphere, 2022

Geological models from outcrop analogues are often utilized as a guide, or soft constraint, for d... more Geological models from outcrop analogues are often utilized as a guide, or soft constraint, for distributing reservoir properties in subsurface models. In carbonate outcrops, combined sequence stratigraphic, sedimentological, and petrographic studies constrain the heterogeneity of geobodies and diagenetic processes, including dolomitization, at multiple scales. High-resolution digital outcrop modeling further aids geometric mapping, geobody definition, and statistical analysis, though its usefulness for detailed mineralogical and lithological mapping is limited. Hyperspectral imaging offers enhanced spectral resolution for mapping subtle mineralogical differences. In both outcrops and subsurface, differences in carbonate composition can provide key information for distributing porosity and permeability, yet this mapping is highly challenging in field studies due to access difficulties, visible material differences, and sampling resolution. Spectral analysis of limestone–dolomite rat...

Research paper thumbnail of Introduction to special section: Geophysical imaging and interpretation of outcrops

Research paper thumbnail of Pennsylvanian high-relief microbial boundstone-dominated carbonate platform margins (Sierra del Cuera, Asturias, Spain)

Field guides to exceptionally exposed carbonate outcrops, Dec 31, 2021

Research paper thumbnail of Mineralogical Mapping with Accurately Corrected Shortwave Infrared Hyperspectral Data Acquired Obliquely from UAVs

Remote. Sens., 2022

While uncrewed aerial vehicles are routinely used as platforms for hyperspectral sensors, their a... more While uncrewed aerial vehicles are routinely used as platforms for hyperspectral sensors, their application is mostly confined to nadir imaging orientations. Oblique hyperspectral imaging has been impeded by the absence of robust registration and correction protocols, which are essential to extract accurate information. These corrections are especially important for detecting the typically small spectral features produced by minerals, and for infrared data acquired using pushbroom sensors. The complex movements of unstable platforms (such as UAVs) require rigorous geometric and radiometric corrections, especially in the rugged terrain often encountered for geological applications. In this contribution we propose a novel correction methodology, and associated toolbox, dedicated to the accurate production of hyperspectral data acquired by UAVs, without any restriction concerning view angles or target geometry. We make these codes freely available to the community, and thus hope to tri...

Research paper thumbnail of Case History Acoustic properties of carbonates: Effects of rock texture

More than 250 plugs from outcrops and three nearby boreholes in an undisturbed reef of Miocene ͑T... more More than 250 plugs from outcrops and three nearby boreholes in an undisturbed reef of Miocene ͑Tortonian͒ age were quantitatively analyzed for texture, mineralogy, and acoustic properties. We measured the P-and S-waves of carbonate rocks under dry ͑humidified͒ and brine-saturated conditions at 10 MPa effective pressure with an ultrasonic pulse transmission technique ͑1 MHz͒. The data set was compared with an extensive database of petrophysical measurements of a variety of rock types encountered in carbonate sedimentary sequences. Two major textural groups were distinguished on the basis of trends in plots of compressional-wave velocity versus Poisson's ratio ͑a specific ratio of P-wave over S-wave velocity͒. In granular rocks, the framework of depositional grains is the main medium for acoustic-wave propagation; in crystalline rocks, this medium is provided by a framework of interlocking crystals formed during diagenesis. Rock textures are connected to primary depositional parameters and a diagenetic overprint through the specific effects on Poisson's ratio. Calculating acoustic velocities using Gassmann fluid substitution modeling approximates measured saturated velocities for 55% of the samples ͑3% error tolerance͒; however, it shows considerable errors because shear modulus changes with saturation. Introducing brine into the pore space may decrease the shear modulus of the rock by approximately 1.4 GPa or, alternatively, increase it by approximately 1.4 GPa. This change in shear modulus is coupled with the texture of the rock. In granular carbonates, the shear modulus decreases; in crystalline and cemented carbonates, it increases with saturation. The results demonstrate the intimate relationship between elastic behavior and the depositional and diagenetic properties of carbonate sedimentary rocks. The results potentially allow the direct extraction of granular and crystalline rock texture from acoustic data alone and may help predict rock types from seismic data and in wells.

Research paper thumbnail of Strategies for Modeling Depositional Heterogeneity of Carbonate Ramps UsingOutcrop Analogs and Multiple Point Statistics

Research paper thumbnail of Slope angle and basin depth of the Triassic platform-basin transition at the Gosaukamm, Austria

Austrian Journal of Earth Sciences, 2009

Large-scale, steep and straight bedding is present in exposures of the Triassic Dachstein carbona... more Large-scale, steep and straight bedding is present in exposures of the Triassic Dachstein carbonate platform slope at the Gosaukamm, Austria. Field observations revealed high and planar clinoforms with declivities of ca. 30° and bedding thicknesses varying between 1 and 100 m. The sediment is mainly composed of poorly sorted mixtures of carbonate sand and gravel, almost devoid of mud. Measurements of geopetal fabrics and the flat stratigraphic boundary of clinoforms and underlying cherty basin limestones (Gosauseekalk) both indicate that the clinoforms are dipping more or less at their original depositional angle of 30°. Tracing of clinoforms yields a minimum estimate of the platform-basin relief of 300 m, while depositional relief exceeding 500 m is most likely. Even the most conservative estimate of water depth puts the basin floor below the neritic realm, supporting the deep-basin model of the Hallstatt zones. However, moderate uplift of the basins relative to the platforms durin...

Research paper thumbnail of Oligocene and Miocene Global Spatial Trends of Shallow-Marine Carbonate Architecture

The Journal of Geology

The present study provides the baseline status of the spatial distribution of carbonate platforms... more The present study provides the baseline status of the spatial distribution of carbonate platforms for the Oligo-Miocene interval. The resulting global trend quantitatively shows the decreasing growth potential of shallow-marine carbonates toward higher paleolatitudes. Such a global trend provides a geological context and external constraints for local and regional interpretations of specific case studies. Furthermore, the direct relationship between carbonate accumulations and paleoclimatic regions shows that, using such a qualitative and quantitative data set for calibration, paleoceanographic models could be utilized for the prediction of the global distribution of carbonate stratigraphic architecture.

Research paper thumbnail of Joint Systems and Fault-Controlled Hydraulic Fracturing in Outcrops – Impact on Precitions of Reservoir Properties

1st EAGE North African/Mediterranean Petroleum & Geosciences Conference & Exhibition

Research paper thumbnail of Microbial boundstone dominated carbonate slope (Upper Carboniferous, N Spain): Microfacies, lithofacies distribution and stratal geometry

Facies

The Carboniferous, particularly during the Serpukhovian and Bashkirian time, was a period of scar... more The Carboniferous, particularly during the Serpukhovian and Bashkirian time, was a period of scarce shallow-water calcimicrobial-microbialite reef growth. Organic frameworks developed on high-rising platforms are, however, recorded in the Precaspian Basin subsurface, ...

Research paper thumbnail of Synthetic Seismograms at Site 866: Origin of Reflections and Implications for Recognizing the Limestone-Basalt Transition in Cretaceous Mid-Pacific Guyots

Proceedings of the Ocean Drilling Program, 143 Scientific Results

Synthetic seismograms at Hole 866 were derived from sonic velocity and neutron density logs and c... more Synthetic seismograms at Hole 866 were derived from sonic velocity and neutron density logs and compared to the lithology and seismic reflection data. In addition, logs of neutron density, neutron porosity, resistivity, gamma-ray, and discrete measurements were used to generate pseudo-velocity logs as input for synthetic seismograms to evaluate their potential as proxy for sonic velocity. The experiment has several implications for the study of seismic reflection profiles over Cretaceous Mid-Pacific guyots.

Research paper thumbnail of Acoustic properties from logs and discrete measurements (Sites 966 and 967) on Eratosthenes Seamount: controls and ground truth

Proceedings of the Ocean Drilling Program, 160 Scientific Results

Acoustic properties (P-wave velocities, densities, and porosities) and insoluble residues were me... more Acoustic properties (P-wave velocities, densities, and porosities) and insoluble residues were measured at in situ pressures in 68 core plugs taken from cores recovered at Ocean Drilling Project Sites 966 and 967 and compared with wireline logging data. Study of the parameters that control the acoustic properties and the quality of the logging data reveals: (1) velocity-porosity and velocity-density relationships within the discrete data follow the general trend of the general empirical equation but are offset with respect to it. Insoluble residue and dolomite content are the primary controls on the acoustic velocities of the core plugs, whereas lithologic facies has no or a minor effect; and (2) velocity-porosity and velocity-density relationships in the logging data show considerable deviation and trends that cross those from the general relationships that are believed to approximate fundamental physical principles. Calculated uncertainties in the laboratory measurements are at least one order of magnitude smaller than the difference between laboratory measurements and those from the wireline logs in several intervals. As a consequence, we believe that the downhole wireline measurements are unreliable in large intervals at both sites. Possible causes of the unreliability are poor hole conditions, upscaling effects, and consequent difficulties in making realistic corrections of the raw log data. The wireline logs were found to be of such poor quality that they are untrustworthy sources of acoustic parameters for making synthetic seismograms. This study clearly indicates that logging data should be carefully evaluated and calibrated with petrophysical relationships from literature and from discrete measurements before interpretation or use as input for synthetic seismograms when hole conditions are poor.

Research paper thumbnail of Carbonate petrophysical rock typing: integrating geological attributes and petrophysical properties while linking with dynamic behaviour

Geological Society, London, Special Publications, 2014

Research paper thumbnail of An alternative model for positive shifts in shallow-marine carbonate ��13C and ��18O: An alternative model for carbon and oxygen isotope shifts

Sedimentology, 2003

Positive shifts in global seawater d 13 C DIC are related to changes in the ratio of organic rela... more Positive shifts in global seawater d 13 C DIC are related to changes in the ratio of organic relative to inorganic carbon burial in oceanic basins, whereas factors such as climatic cooling and the accumulation of polar ice are known to cause positive shifts in d 18 O. Here, an alternative model is proposed for the formation of local positive isotope shifts in shallow-marine settings. The model involves geochemically altered platform-top water masses and the effects of early meteoric diagenesis on carbonate isotopic composition. Both mechanisms are active on modern (sub)tropical carbonate platforms and result in low carbonate d 13 C and d 18 O relative to typical oceanic values. During high-amplitude transgressive events, the impact of isotopically light meteoric fluids on the carbonate geochemistry is much reduced, and 13 C-depleted platform-top water mixes with open oceanic water masses having higher isotope values. Both factors are recorded as a transient increase in carbonate 13 C and 18 O relative to low background values. These processes must be taken into consideration when interpreting the geochemical record of ancient epeiric seas.

Research paper thumbnail of A comparison of shear strength in calcareous and siliciclastic marine sediments

Marine Geology, Jul 1, 1989

... In: KR Demars and RC Chancy (Editors), Geotechnical Properties. ... Bearing strength and othe... more ... In: KR Demars and RC Chancy (Editors), Geotechnical Properties. ... Bearing strength and other physical properties of some shallow and deep-sea sediments from the North Pacific. Geol. Soc. Am. ... Shear strength and stability of continental slope deposits, Western Gulf of Mexico. ...

Research paper thumbnail of Sedimentation on a Lower Jurassic carbonate platform flank: geometry, sediment fabric and related depositional structures (Djebel Bou Dahar, High Atlas, Morocco)

Sedimentary Geology, 1991

At ca. 50 m below the platform margin, coral-algal patch reefs and ooid sand shoals grade into th... more At ca. 50 m below the platform margin, coral-algal patch reefs and ooid sand shoals grade into the depositional slope. The straight upper slope, showing discontinuous bedding at angles up to 29°, extends down to ca. 250 m and consists mainly of poorly sorted mixtures of sand ...

Research paper thumbnail of Facies belts of a Carboniferous carbonate platform (San Antolín-La Huelga section, NE Cantabrian Zone)

Trabajos De Geologia, 2008

Research paper thumbnail of Non-Actualistic Carbonate Deposystems: Revi sing The Carbonate Factory-Depth Paradigm

Non-actualistic (e.g., deviating from depositional models developed for recent deposystems) carbo... more Non-actualistic (e.g., deviating from depositional models developed for recent deposystems) carbonate platforms are not the exception in the geologic record because of the wide range of biological and environmental factors controlling facies character and architecture.

Research paper thumbnail of Anatomy and Lithofacies of an Intact and Seismic-Scale Carboniferous Carbonate Platform (Asturias, NW Spain): Analogs of Hydrocarbon Reservoirs in the Pricaspian Basin (Kazakhstan)