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Ian A. Kane - One of the best experts on this subject based on the ideXlab platform.
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differentiating submarine channel related thin bedded turbidite facies outcrop examples from the rosario formation mexico
Sedimentary Geology, 2017Co-Authors: Larissa Hansen, Ian A. Kane, Richard H T Callow, Ben KnellerAbstract:Abstract Thin-bedded turbidites deposited by sediment gravity flows that spill from submarine channels often contain significant volumes of sand in laterally continuous beds. These can make up over 50% of the channel-belt fill volume, and can thus form commercially important hydrocarbon reservoirs. Thin-bedded turbidites can be deposited in environments that include Levees and depositional terraces, which are distinguished on the basis of their external morphology and internal architecture. Levees have a distinctive wedge shaped morphology, thinning away from the channel, and confine both channels (internal Levees) and channel-belts (external Levees). Terraces are flat-lying features that are elevated above the active channel within a broad channel-belt. Despite the ubiquity of terraces and Levees in modern submarine channel systems, the recognition of these environments in outcrop and in the subsurface is challenging. In this outcrop study of the Upper Cretaceous Rosario Formation (Baja California, Mexico), lateral transects based on multiple logged sections of thin-bedded turbidites reveal systematic differences in sandstone layer thicknesses, sandstone proportion, palaeocurrents, sedimentary structures and ichnology between channel-belt and external levee thin-bedded turbidites. Depositional terrace deposits have a larger standard deviation in sandstone layer thicknesses than external Levees because they are topographically lower, and experience a wider range of turbidity current sizes overspilling from different parts of the channel-belt. The thickness of sandstone layers within external Levees decreases away from the channel-belt while those in depositional terraces are less laterally variable. Depositional terrace environments of the channel-belt are characterized by high bioturbation intensities, and contain distinctive trace fossil assemblages, often dominated by ichnofabrics of the echinoid trace fossil Scolicia. These assemblages contrast with the lower bioturbation intensities that are recorded from external levee environments where Scolicia is typically absent. Multiple blocks of external levee material are observed in the depositional terrace area where the proximal part of the external levee has collapsed into the channel-belt; their presence characterizes the channel-belt boundary zone. The development of recognition criteria for different types of channel-related thin-bedded turbidites is critical for the interpretation of sedimentary environments both at outcrop and in the subsurface, which can reduce uncertainty during hydrocarbon field appraisal and development.
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sedimentological criteria to differentiate submarine channel levee subenvironments exhumed examples from the rosario fm upper cretaceous of baja california mexico and the fort brown fm permian karoo basin s africa
Marine and Petroleum Geology, 2011Co-Authors: Ian A. Kane, David M. HodgsonAbstract:Two scales of levee confinement are commonly recognised from submarine channel-levee systems on the seafloor and in the subsurface. Large-scale external Levees bound the entire system whilst smaller-scale internal Levees bound individual thalweg channels within the channel-belt. Although thin beds are commonly identified in core and well logs, their origin, and consequently their stratigraphic significance is currently poorly understood. This knowledge gap stems, in part, from the lack of unambiguously identified outcrop analogues of channel-Levees, and in particular the lack of identifiable internal and external Levees. Here we report from two exhumed channel-levee systems where both scales of confinement can be recognised: the Rosario Fm. of Baja California, and the Fort Brown Fm. of South Africa. A suite of characteristic sedimentary features are recognised from internal and external Levees respectively: internal Levees are characterised by structures indicative of complexity in the waxing-waning style of overspill, interactions with topography and flow magnitude variability; in contrast, external Levees are characterised by structures indicative of simple surge-like waning flows, relatively uniform flow directions, laterally extensive beds, and a lack of erosive events. Using these observations, together with published literature, we propose a simple nomenclatural scheme for levee sub-environments, and criteria to differentiate between levee sub-environments in core or outcrop.
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submarine channel levee shape and sediment waves from physical experiments
Sedimentary Geology, 2010Co-Authors: Ian A. Kane, Jeff Peakall, William D Mccaffrey, Benjamin Charles KnellerAbstract:Abstract Submarine channel Levees aggrade through repeated overspill events from the channel axis. The shape of the Levees may therefore reflect some characteristic(s) of the overspilling flow. It has been noted that basin floor Levees typically have a relatively low-relief and taper exponentially to their termination; in contrast slope channel Levees may be much steeper close to the channel. A simple physical experiment was performed where a surge-like sediment-laden current flowed through a curved channel. Significant overspill occurred and generated a deposit flanking the channel on either side. The experiment was repeated 25 times to build up low-relief channel-Levees. It was found that in proximal areas, Levees were steep and characterised by power-law decays, a transitional zone of logarithmically thinning levee was found a little further down-channel, followed by exponential decays in medial to distal areas. The style of levee decay is a function of spatial variation in overbank sedimentation rates. Where flows rapidly lose momentum and deposit across the grain-size spectrum, i.e., in proximal areas, Levees tend to be steep; farther down the channel, the steep levee slope gives way to a more gradually tapering deposit. In more distal parts of the channel, deposition is directly related to sediment settling velocity (rather than the suspended load exceeding flow transport capacity as is the case in proximal areas), the deposit reflects this with relatively simple exponential thickness decays. Additionally, small-scale sediment waves developed under lee wave conditions on the inner-bend overbank. The waves initially migrated slightly towards the channel, but as the style of overspill evolved due to intra-channel deposition, flows moved out of the lee wave window and sedimentation became out of phase with the wavelength of the features and the topography was healed.
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anatomy of a submarine channel levee an example from upper cretaceous slope sediments rosario formation baja california mexico
Marine and Petroleum Geology, 2007Co-Authors: Ian A. Kane, Mason Dykstra, Benjamin Charles Kneller, Ahmed Kassem, William D MccaffreyAbstract:Abstract To date, facies architecture models of submarine channel–Levees have largely been derived from seismic data, isolated core data and limited field studies. We report field observations of an Upper Cretaceous submarine channel–levee complex within the Rosario Formation, Baja California, Mexico, which provide high-resolution data of lithofacies and ichnofacies distribution, and levee depositional thickness decay along transects perpendicular to the channel axis. Within the levee, both sandstone thickness and the overall proportion of sandstone decrease according to a power law away from the channel axis. Spatial variation in sedimentary structures away from the channel axis is predictable and provides an important link to the depositional flow regime. In channel-proximal locations, structureless sands, parallel lamination, overturned ripples, and ripple cross-lamination (including climbing ripple cross-lamination) are common; in channel-distal localities starved ripples are abundant. Sandstone bed thickness generally increases up stratigraphy within the levee succession, which is interpreted to indicate increasing turbidity current magnitude and/or contemporaneous channel floor aggradation reducing relative levee relief. However, in the most channel-proximal location sandstone bed thickness decreases with height; combined with evidence from both facies and palaeocurrent analysis this allows the position of the levee crest to be inferred. The thickest beds occur at higher levels with increasing distance from the channel axis, using this evidence we present a model for levee growth and migration of the crest. Quantitative analysis of ichnofacies distribution reveals that traces typical of the Cruziana and Skolithos ichnofacies are superimposed over the ‘normal’ background Nereites ichnofacies, forming a ‘bioturbation front’ which is indicative of proximity to the channel. By analogy with modern canyons and channels, the association of Cruziana and Skolithos ichnofacies with the channel may be attributed to oxygen and nutrient enrichment and possible turbidity current transport of organisms responsible for these ichnofacies.
David M. Hodgson - One of the best experts on this subject based on the ideXlab platform.
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integrating outcrop and subsurface data to assess the temporal evolution of a submarine channel levee system
AAPG Bulletin, 2016Co-Authors: Emma A Morris, Stephen S Flint, Rufus L Brunt, Stefan M Luthi, David M. Hodgson, Yolanda KolenbergAbstract:The morphological evolution of submarine channel systems can be documented using high-resolution three-dimensional seismic data sets. However, these studies provide limited information on the distribution of sedimentary facies within channel fills, channel-scale stacking patterns, or the detailed stratigraphic relationship with adjacent levee-overbank deposits. Seismic-scale outcrops of unit C2 in the Permian Fort Brown Formation, Karoo Basin, South Africa, on two subparallel fold limbs comprise thin-bedded successions, interpreted as external levee deposits, which are adjacent to channel complexes, with constituent channels filled with thick-bedded structureless sandstones, thinner-bedded channel margin facies, and internal levee deposits. Research boreholes intersect all these deposits, to link sedimentary facies and channel stacking patterns identified in core and on image logs and detailed outcrop correlation panels. Key characteristics, including depth of erosion, stacking patterns, and cross-cutting relationships, have been constrained, allowing paleogeographic reconstruction of six channel complexes in a 36-km2 (14-mi2) area. The system evolved from an early, deeply incised channel complex, through a series of external levee-confined and laterally stepping channel complexes culminating in an aggradational channel complex confined by both internal and external Levees. Down-dip divergence of six channel complexes from the same location suggests the presence of a unique example of an exhumed deep-water avulsion node. Down-dip, external Levees are supplied by flows that escaped from channel complexes of different ages and spatial positions and are partly confined and share affinities with internal levee successions. The absence of frontal lobes suggests that the channels remained in sand bypass mode immediately after avulsion.
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origin evolution and anatomy of silt prone submarine external Levees
Sedimentology, 2014Co-Authors: Emma A Morris, Rufus L Brunt, David M. Hodgson, Stephen S FlintAbstract:Submarine external Levees are constructional features that develop outside slope channel systems, and are a volumetrically significant component of continental margins. However, detailed observations of their process sedimentology and depositional architecture are rare. Extensive exposures of external Levees at multiple stratigraphic intervals and well-constrained palaeogeographic positions in the Fort Brown Formation, Karoo Basin, South Africa, have been calibrated with research boreholes. This integrated data set permits their origin, evolution and anatomy to be considered, including high-resolution analysis of sedimentary facies distribution and characterization of depositional sub-environments. An idealized model of the stratigraphic evolution and depositional architecture of external Levees is presented, and variations can be attributed to allogenic (for example, sediment supply) and autogenic (for example, channel migration) factors. Initiation of external levee construction is commonly marked by deposition of a basal sand-rich facies with sedimentary structures indicating rapid deposition from unconfined flows. These deposits are interpreted as frontal lobes. Propagation of the parent channel, and resultant flow confinement, lead to partial erosion of the frontal lobe and development of constructional relief (Levees) by flow overspill and flow stripping. Overall fining-upwards and thinning-upwards profiles reflect increased flow confinement and/or waning flow magnitude through time. Identification of a hierarchy of levee elements is not possible due to the absence of internal bounding surfaces or sharp facies changes. The down-slope taper in levee height and increasing channel sinuosity results in increasing numbers of crevasse lobe deposits, and is reflected by the increased occurrences of channel avulsion events down-dip. External Levees from the Fort Brown Formation are silt-rich; however their stratigraphic evolution and the distribution of many components (such as sediment waves and crevasse lobe) share commonalities with mud-rich external Levees. This unique integrated data set has permitted the first high-resolution characterization of external submarine levee systems.
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sedimentological criteria to differentiate submarine channel levee subenvironments exhumed examples from the rosario fm upper cretaceous of baja california mexico and the fort brown fm permian karoo basin s africa
Marine and Petroleum Geology, 2011Co-Authors: Ian A. Kane, David M. HodgsonAbstract:Two scales of levee confinement are commonly recognised from submarine channel-levee systems on the seafloor and in the subsurface. Large-scale external Levees bound the entire system whilst smaller-scale internal Levees bound individual thalweg channels within the channel-belt. Although thin beds are commonly identified in core and well logs, their origin, and consequently their stratigraphic significance is currently poorly understood. This knowledge gap stems, in part, from the lack of unambiguously identified outcrop analogues of channel-Levees, and in particular the lack of identifiable internal and external Levees. Here we report from two exhumed channel-levee systems where both scales of confinement can be recognised: the Rosario Fm. of Baja California, and the Fort Brown Fm. of South Africa. A suite of characteristic sedimentary features are recognised from internal and external Levees respectively: internal Levees are characterised by structures indicative of complexity in the waxing-waning style of overspill, interactions with topography and flow magnitude variability; in contrast, external Levees are characterised by structures indicative of simple surge-like waning flows, relatively uniform flow directions, laterally extensive beds, and a lack of erosive events. Using these observations, together with published literature, we propose a simple nomenclatural scheme for levee sub-environments, and criteria to differentiate between levee sub-environments in core or outcrop.
William D Mccaffrey - One of the best experts on this subject based on the ideXlab platform.
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submarine channel levee shape and sediment waves from physical experiments
Sedimentary Geology, 2010Co-Authors: Ian A. Kane, Jeff Peakall, William D Mccaffrey, Benjamin Charles KnellerAbstract:Abstract Submarine channel Levees aggrade through repeated overspill events from the channel axis. The shape of the Levees may therefore reflect some characteristic(s) of the overspilling flow. It has been noted that basin floor Levees typically have a relatively low-relief and taper exponentially to their termination; in contrast slope channel Levees may be much steeper close to the channel. A simple physical experiment was performed where a surge-like sediment-laden current flowed through a curved channel. Significant overspill occurred and generated a deposit flanking the channel on either side. The experiment was repeated 25 times to build up low-relief channel-Levees. It was found that in proximal areas, Levees were steep and characterised by power-law decays, a transitional zone of logarithmically thinning levee was found a little further down-channel, followed by exponential decays in medial to distal areas. The style of levee decay is a function of spatial variation in overbank sedimentation rates. Where flows rapidly lose momentum and deposit across the grain-size spectrum, i.e., in proximal areas, Levees tend to be steep; farther down the channel, the steep levee slope gives way to a more gradually tapering deposit. In more distal parts of the channel, deposition is directly related to sediment settling velocity (rather than the suspended load exceeding flow transport capacity as is the case in proximal areas), the deposit reflects this with relatively simple exponential thickness decays. Additionally, small-scale sediment waves developed under lee wave conditions on the inner-bend overbank. The waves initially migrated slightly towards the channel, but as the style of overspill evolved due to intra-channel deposition, flows moved out of the lee wave window and sedimentation became out of phase with the wavelength of the features and the topography was healed.
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anatomy of a submarine channel levee an example from upper cretaceous slope sediments rosario formation baja california mexico
Marine and Petroleum Geology, 2007Co-Authors: Ian A. Kane, Mason Dykstra, Benjamin Charles Kneller, Ahmed Kassem, William D MccaffreyAbstract:Abstract To date, facies architecture models of submarine channel–Levees have largely been derived from seismic data, isolated core data and limited field studies. We report field observations of an Upper Cretaceous submarine channel–levee complex within the Rosario Formation, Baja California, Mexico, which provide high-resolution data of lithofacies and ichnofacies distribution, and levee depositional thickness decay along transects perpendicular to the channel axis. Within the levee, both sandstone thickness and the overall proportion of sandstone decrease according to a power law away from the channel axis. Spatial variation in sedimentary structures away from the channel axis is predictable and provides an important link to the depositional flow regime. In channel-proximal locations, structureless sands, parallel lamination, overturned ripples, and ripple cross-lamination (including climbing ripple cross-lamination) are common; in channel-distal localities starved ripples are abundant. Sandstone bed thickness generally increases up stratigraphy within the levee succession, which is interpreted to indicate increasing turbidity current magnitude and/or contemporaneous channel floor aggradation reducing relative levee relief. However, in the most channel-proximal location sandstone bed thickness decreases with height; combined with evidence from both facies and palaeocurrent analysis this allows the position of the levee crest to be inferred. The thickest beds occur at higher levels with increasing distance from the channel axis, using this evidence we present a model for levee growth and migration of the crest. Quantitative analysis of ichnofacies distribution reveals that traces typical of the Cruziana and Skolithos ichnofacies are superimposed over the ‘normal’ background Nereites ichnofacies, forming a ‘bioturbation front’ which is indicative of proximity to the channel. By analogy with modern canyons and channels, the association of Cruziana and Skolithos ichnofacies with the channel may be attributed to oxygen and nutrient enrichment and possible turbidity current transport of organisms responsible for these ichnofacies.
Nicolas H. Younan - One of the best experts on this subject based on the ideXlab platform.
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Screening Mississippi River Levees Using Texture-Based and Polarimetric-Based Features from Synthetic Aperture Radar Data
MDPI AG, 2017Co-Authors: Lalitha Dabbiru, James V. Aanstoos, John E. Ball, Nicolas H. YounanAbstract:This article reviews the use of synthetic aperture radar remote sensing data for earthen levee mapping with an emphasis on finding the slump slides on the Levees. Earthen Levees built on the natural Levees parallel to the river channel are designed to protect large areas of populated and cultivated land in the Unites States from flooding. One of the signs of potential impending levee failure is the appearance of slump slides. On-site inspection of Levees is expensive and time-consuming; therefore, a need to develop efficient techniques based on remote sensing technologies is mandatory to prevent failures under flood loading. Analysis of multi-polarized radar data is one of the viable tools for detecting the problem areas on the Levees. In this study, we develop methods to detect anomalies on the levee, such as slump slides and give levee managers new tools to prioritize their tasks. This paper presents results of applying the National Aeronautics and Space Administration (NASA) Jet Propulsion Lab (JPL)’s Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) quad-polarized L-band data to detect slump slides on earthen Levees. The study area encompasses a portion of Levees of the lower Mississippi River in the United States. In this paper, we investigate the performance of polarimetric and texture features for efficient levee classification. Texture features derived from the gray level co-occurrence (GLCM) matrix and discrete wavelet transform were computed and analyzed for efficient levee classification. The pixel-based polarimetric decomposition features, such as entropy, anisotropy, and scattering angle were also computed and applied to the support vector machine classifier to characterize the radar imagery and compared the results with texture-based classification. Our experimental results showed that inclusion of textural features derived from the SAR data using the discrete wavelet transform (DWT) features and GLCM features provided higher overall classification accuracies compared to the pixel-based polarimetric features
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a machine learning framework for detecting landslides on earthen Levees using spaceborne sar imagery
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2015Co-Authors: Majid Mahrooghy, James V. Aanstoos, Rodrigo Affonso De Albuquerque Nobrega, Khaled Hasan, Saurabh Prasad, Nicolas H. YounanAbstract:Earthen Levees have a significant role in protecting large areas of inhabited and cultivated land in the United States from flooding. Failure of the Levees can result in loss of life and property. Slough slides are among the problems which can lead to complete levee failure during a high water event. In this paper, we develop a method to detect such slides using X-band synthetic aperture radar (SAR) data. Our proposed methodology includes: 1) radiometric normalization of the TerraSAR image using high-resolution digital elevation map (DEM) data; 2) extraction of features including backscatter and texture features from the levee; 3) a feature selection method based on minimum redundancy maximum relevance (mRMR); and 4) training a support vector machine (SVM) classifier and testing on the area of interest. To validate the proposed methodology, ground-truth data are collected from slides and healthy areas of the levee. The study area is part of the levee system along the lower Mississippi River in the United States. The output classes are healthy and slide areas of the levee. The results show the average classification accuracies of approximately 0.92 and Cohen’s kappa measures of 0.85 for both healthy and slide pixels using ten optimal features selected by mRMR with a sigmoid SVM. A comparison of the SVM performance to the maximum likelihood (ML) and back propagation neural network (BPNN) shows that the average accuracy of the SVM is superior to that of the BPNN and ML classifiers.
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landslide detection on earthen Levees with x band and l band radar data
Applied Imagery Pattern Recognition Workshop, 2013Co-Authors: Lalitha Dabbiru, James V. Aanstoos, Khaled Hasan, Nicolas H. YounanAbstract:This paper explores anomaly detection algorithms to detect vulnerabilities on Mississippi river Levees using remotely sensed Synthetic Aperture Radar (SAR) data. Earthen Levees protect large areas of populated and cultivated land in the United States. One sign of potential levee failure is the occurrence of landslides due to slope instabilities. Such slides could lead to further erosion and through seepage during high water events. This research seeks to design a system that is capable of performing automated target recognition tasks using radar data to detect problem areas on earthen Levees. Polarimetric SAR data is effective for detecting such phenomena. In this research, we analyze the ability of different polarization channels in detecting landslides with different frequency bands of synthetic aperture radar data using anomaly detection algorithms. The two SAR datasets used in this study are: (1) the X-band satellite-based radar data from DLR's TerraSAR-X satellite, and (2) the L-band airborne radar data from NASA's Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR). The RX anomaly detector, an unsupervised classification algorithm, was implemented to detect anomalies on the levee. The discrete wavelet transform (DWT) is used for feature extraction. The algorithm was tested with both the L-band and X-band SAR data and the results demonstrate that landslide detection using L-band radar data has better accuracy compared to the X-band data based on the detection of true positives.
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classification of Levees using polarimetric synthetic aperture radar sar imagery
Applied Imagery Pattern Recognition Workshop, 2010Co-Authors: Lalitha Dabbiru, James V. Aanstoos, Nicolas H. YounanAbstract:The recent catastrophe caused by hurricane Katrina emphasizes the importance of examination of Levees to improve the condition of those that are prone to failure during floods. On-site inspection of Levees is costly and time-consuming, so there is a need to develop efficient techniques based on remote sensing technologies to identify Levees that are more vulnerable to failure under flood loading. This research uses NASA JPL's Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) backscatter data for classification and analysis of earthen Levees. The overall purpose of this research is to detect the problem areas along the levee such as through-seepage, sand boils and slough slides. This paper focuses on detection of slough slides. Since the UAVSAR is a quad-polarized L-band (λ = 25 cm) radar, the radar signals penetrate into the soil which aids in detecting soil property variations in the top layer. The research methodology comprises three steps: initially the SAR image is classified into three scattering components using the Freeman-Durden decomposition algorithm; then unsupervised classification is performed based on the polarimetric decomposition parameters: entropy (H) and alpha (α); and finally reclassified using the Wishart classifier. A 3×3 coherency matrix is calculated for each pixel of the radar's compressed Stokes matrix multi-look backscatter data and is used to retrieve these parameters. Different scattering mechanisms like surface scattering, dihedral scattering and volume scattering are observed to distinguish different targets along the levee. The experimental results show that the Wishart classifier can be used to detect slough slides on Levees.
Benjamin Charles Kneller - One of the best experts on this subject based on the ideXlab platform.
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submarine channel levee shape and sediment waves from physical experiments
Sedimentary Geology, 2010Co-Authors: Ian A. Kane, Jeff Peakall, William D Mccaffrey, Benjamin Charles KnellerAbstract:Abstract Submarine channel Levees aggrade through repeated overspill events from the channel axis. The shape of the Levees may therefore reflect some characteristic(s) of the overspilling flow. It has been noted that basin floor Levees typically have a relatively low-relief and taper exponentially to their termination; in contrast slope channel Levees may be much steeper close to the channel. A simple physical experiment was performed where a surge-like sediment-laden current flowed through a curved channel. Significant overspill occurred and generated a deposit flanking the channel on either side. The experiment was repeated 25 times to build up low-relief channel-Levees. It was found that in proximal areas, Levees were steep and characterised by power-law decays, a transitional zone of logarithmically thinning levee was found a little further down-channel, followed by exponential decays in medial to distal areas. The style of levee decay is a function of spatial variation in overbank sedimentation rates. Where flows rapidly lose momentum and deposit across the grain-size spectrum, i.e., in proximal areas, Levees tend to be steep; farther down the channel, the steep levee slope gives way to a more gradually tapering deposit. In more distal parts of the channel, deposition is directly related to sediment settling velocity (rather than the suspended load exceeding flow transport capacity as is the case in proximal areas), the deposit reflects this with relatively simple exponential thickness decays. Additionally, small-scale sediment waves developed under lee wave conditions on the inner-bend overbank. The waves initially migrated slightly towards the channel, but as the style of overspill evolved due to intra-channel deposition, flows moved out of the lee wave window and sedimentation became out of phase with the wavelength of the features and the topography was healed.
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anatomy of a submarine channel levee an example from upper cretaceous slope sediments rosario formation baja california mexico
Marine and Petroleum Geology, 2007Co-Authors: Ian A. Kane, Mason Dykstra, Benjamin Charles Kneller, Ahmed Kassem, William D MccaffreyAbstract:Abstract To date, facies architecture models of submarine channel–Levees have largely been derived from seismic data, isolated core data and limited field studies. We report field observations of an Upper Cretaceous submarine channel–levee complex within the Rosario Formation, Baja California, Mexico, which provide high-resolution data of lithofacies and ichnofacies distribution, and levee depositional thickness decay along transects perpendicular to the channel axis. Within the levee, both sandstone thickness and the overall proportion of sandstone decrease according to a power law away from the channel axis. Spatial variation in sedimentary structures away from the channel axis is predictable and provides an important link to the depositional flow regime. In channel-proximal locations, structureless sands, parallel lamination, overturned ripples, and ripple cross-lamination (including climbing ripple cross-lamination) are common; in channel-distal localities starved ripples are abundant. Sandstone bed thickness generally increases up stratigraphy within the levee succession, which is interpreted to indicate increasing turbidity current magnitude and/or contemporaneous channel floor aggradation reducing relative levee relief. However, in the most channel-proximal location sandstone bed thickness decreases with height; combined with evidence from both facies and palaeocurrent analysis this allows the position of the levee crest to be inferred. The thickest beds occur at higher levels with increasing distance from the channel axis, using this evidence we present a model for levee growth and migration of the crest. Quantitative analysis of ichnofacies distribution reveals that traces typical of the Cruziana and Skolithos ichnofacies are superimposed over the ‘normal’ background Nereites ichnofacies, forming a ‘bioturbation front’ which is indicative of proximity to the channel. By analogy with modern canyons and channels, the association of Cruziana and Skolithos ichnofacies with the channel may be attributed to oxygen and nutrient enrichment and possible turbidity current transport of organisms responsible for these ichnofacies.