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January 2003 - December 2012
August 2000 - July 2003
Education
September 1999
Publications
Publications (359)
Integrated ichnological and sedimentological analyses of core samples from the Upper Jurassic Ula Formation in the Norwegian Central Graben was undertaken to quantify the influence of storm waves on sedimentation. Two main facies associations (offshore and shoreface) that form a progradational coarsening upward succession are recognizable within th...
A detailed study of burrow-associated dolomites and their influence on permeability distribution was conducted on the Upper Devonian Wabamun Group in the Pine Creek gas field of central Alberta, Canada using sample imaging (micro-CT and helical-CT), spot-permeametry, and numerical modeling techniques. Spot-permeametry shows that the permeability of...
Complex animals first evolved during the Ediacaran period, between 635 and 542 million years ago, when the oceans were just becoming fully oxygenated. In situ fossils of the mobile forms of these animals are associated with microbial sedimentary structures, and the animal's trace fossils generally were formed parallel to the surface of the seabed,...
Based on molecular clocks and biomarker studies, it is possible that bilaterian life emerged early in the Ediacaran, but at
present, no fossils or trace fossils from this time have been reported. Here we report the discovery of the oldest bilaterian
burrows in shallow-water glaciomarine sediments from the Tacuarí Formation, Uruguay. Uranium-lead da...
An array of trace fossils have been ascribed to brittle-star behaviors including locomotion traces such as Biformites. Brittle-star locomotion has been well described but little work has been done to link modern brittle-star behavior to the trace fossil record. To draw this connection, a brittle star was kept in an aquarium and isolated in a “walki...
Sea turtles are characterized by a wide variety of invertebrate ectoparasites. Few of these ectoparasites leave a permanent indication of their presence on the skeletal remains of their host taxa and thus represent ecological information doomed to be lost in the paleontological record. Some barnacle taxa provide an exception to this, in that they c...
Fluvio-tidal estuary deposits are characterized by abundant channel-associated dunes, compound dunes and point bar deposits. The delineation of boundaries between different point bars to identify genetically unrelated packages is difficult to assess, particularly where similarly dipping bars are superimposed on each other. This study uses an outcro...
Low-level drone photogrammetry is a technique that allows for the construction of surface orthomosaics and elevation models. Despite being used for a wide range of geological applications, these types of datasets have not yet been explored from a neoichnological perspective. This study uses three examples of tidal flats from the Bay of Fundy to dem...
Nine facies are recognised in two mid-Pliocene cores from the Columbus Basin, offshore east coast Trinidad. Facies successions are consistent with deposition within a deltaic-shoreface continuum. Lower shoreface deposits are heavily bioturbated by Scolicia, Asterosoma, Thalassinoides, Teichichnus, Palaeophycus and other elements of the Cruziana Ich...
Over the past couple decades, the understanding of petrophysical parameters in bioturbated hydrocarbon reservoirs and aquifers has expanded greatly. Specifically, insights into how bioturbation impacts the distributions of porosity and permeability has occurred through both direct measurements (spot-permeameter, high-resolution imaging) and compute...
Hydrocarbon production from the Lower Triassic Montney Formation in northeastern British Columbia, occurs primarily from unconventional reservoirs consisting predominantly of fine-to coarse-grained siltstone beds. In this area, the lithostratigraphy of the formation is difficult to characterize due to the complexities associated with subtle grain-s...
Shorebirds produce a range of biogenic sedimentary structures related to their feeding behaviors, the most common of which are probing behaviors that result in morphologically simple impressions or indentations on the surface of a sedimentary substrate. Here we describe an unusual biodeformational structure made by a feeding gull (Larus sp.) produc...
The characterization of porosity is an essential step in the evaluation of resource-bearing porous media. Here, we focus on the Devonian Hare Indian and Canol Formations, two potential unconventional mudstone reservoirs, in a core from the Horn River Group of the Central Mackenzie Valley, Northwest Territories, Canada. By combining bulk porosity, l...
Phrases incorporating the modifier ‘mark’ (e.g., bite mark, tooth mark, gnaw mark, etc.) have recently come under attack. These phrases are wide-spread in their usage, and are, in fact, appropriate to the original definition of the word mark. Phrases such as bite mark and tooth mark are de rigueur as interpretive terms in the larger scientific comm...
The combination of hydraulic fracturing with horizontal drilling has revolutionized oil and gas production. However, most of our understanding of the subsurface mechanisms and chemical interactions that occur during the process come from analyses of flowback and produced water (FPW). While the chemical composition of FPW can provide some informatio...
The Hare Indian Formation (HIF) is a late Eifelian to Givetian organic-rich mudstone constituting the lower portion of the Horn River Group (HRG), which has been minimally scrutinized in the literature. This paper proposes depositional environments and a sequence stratigraphic framework for the HIF. Using composition data collected via energy-dispe...
The Lower Cretaceous McMurray Formation contains crude bitumen reserves of the Athabasca Oilsands that formed by channel amalgamation and lateral migration of fluvio-tidal point bars. These point bars are widely accepted as incised valley fills during episodic base-level rises in tidally influenced estuary (Mathison, 2004; Boyd et al., 2006; Hein e...
Fossils are useful as palaeoenvironmental indicators when evaluated using large occurrence and lithology association data sets and/or functional morphology. However, when functional morphology is invoked on an ad hoc basis there exists a risk of circular reasoning. Performance spaces/landscapes constructed using biomechanical experiments can be use...
The reservoir quality of the Lower Triassic (Induan-Olenekian) Montney Formation of the Puskwaskau Field is assessed from two cored intervals. Four lithofacies are identified in the present study mainly based on detailed sedimentological characteristics. Lithofacies 1 (L-1) is composed of interlaminated bituminous very fine- to medium-grained silts...
Cement-rock interface is a major component of the wellbore barrier system. Leakage may result from the poor bonding between cement and rock interface. In this paper we investigate possible factors that may affect the cement-rock interface bonding. More specifically, integrity of the cement-rock interface was characterized using micro-computed tomog...
Sedimentation velocities of various chemical sediments are typically calculated using Stokes's law. However, applying it to chemical sediments that form in situ in the water column is not ideal because the particle properties do not fulfill many of the assumptions underpinning the applicability of Stokes' law. As a consequence, it has been difficul...
The Hare Indian and Canol Formations, which are part of the Horn River Group in the Northwest Territories, Canada, primarily consist of organic-rich mudstones deposited during the Middle to Late Devonian. The formations were previously considered to represent marine basin fill accumulated in an oxygen-starved distal shelf setting, evidenced by the...
The Medicine Hat Member in Alberta, Canada, is a muddy interval with thin sandstones. However, the sedimentology and stratigraphy are poorly understood – a reflection of the limited knowledge of mud-dominated successions. Here facies analysis and stratigraphy from core and wireline logs were used to construct a depositional framework for the interv...
One of the most important contributions that S. George Pemberton made to the field of ichnology was the identification that burrowed firmgrounds associated with the Glossifungites Ichnofacies, commonly demarcate important sequence stratigraphic allogenic surfaces, and more recently described autogenic surfaces. This study considers an outcrop examp...
Ichnological data are integrated with sedimentologic data and body fossil content to reconsider the origins of the biogenic sedimentary structures in upper middle Eocene strata of Wadi El-Hitan (UNESCO universal heritage area) in Egypt. Three types of rhizoliths (Type 1 to 3) are recognized, in addition to co-occurrence of six common marine ichnoge...
Cyanobacteria are abundant in nearly every surface environment on Earth. Understanding their chemical reactivity and metal binding capacity with varying ionic strength (IS) is paramount to understanding trace metal cycling in natural environments. We conducted an investigation on the cell surface reactivity of the freshwater cyanobacterium Synechoc...
Integrity of the cement/casing interface is an essential element of establishing an effective barrier system in cased and cemented wellbores. Failure to establish and maintain an effective barrier can result in negative environmental and economic impacts, such as leakage of formation fluids into the environment or loss of production and costly reme...
Bioturbating organisms contribute significantly to elemental cycling in sediments through burrowing, grazing, organic matter and altering porewater chemical conditions. In the process, organisms are known to produce copious amounts of faecal material at high rates, sometimes in excess of 1 000 000 kg/day in a 1 km² area (Swinbanks, 1981; Pearson &...
A new wood-boring ichnospecies is described from transgressive (lagoonal) deposits of the Lower Cretaceous Sparky Formation (Mannville Group) in west-central Saskatchewan, Canada. Apectoichnus lignummasticans new ichnospecies is a trace fossil that occurs in a thin coal bed and that was emplaced in an in situ xylic substratum (woodground). The ichn...
Given the high surface reactivity of clay minerals, it is assumed that flocculation will lead to metal accumulation in marginal marine settings. However, the degree of metal sorption to clays is impacted by solution pH and ionic strength, and it remains unknown whether riverine clays indeed serve as a metal sink once they encounter seawater where p...
Stress-induced fractures in wellbore cement can form high-risk pathways for methane or carbon dioxide leakage, yet little to no quantitative information on the impact of these fractures has been reported. To investigate this, scanning electron microscopy (SEM) and microcomputed tomography (micro-CT) techniques were used to quantify the 2D and 3D ge...
A proximal distributary channel deposit in the Turonian Ferron Sandstone of central Utah contains a trace-fossil assemblage comprised of turtle tracks (Chelonipus), vertebrate swim trace fossils (Characichnos), repichnial traces of mollusks (Archaeonassa), Rhizocorallium, and Teredolites. Mayflies are abundant producers of horizontal, spreiten, U-s...
The Series 2 and Miaolingian (Lower and Middle) Cambrian succession in the Colville Hills region, Northwest Territories consists (ascending order) of the Mount Clark, Mount Cap and Saline River formations, all of which were deposited in an epicontinental basin, herein named the Colville Basin. The Mount Clark Formation is sandstone-dominated with a...
Sequence stratigraphy is commonly used to understand basin history and the distribution of conventional reservoir facies. Establishing a sequence stratigraphic framework in organic-rich mudstone successions is challenging because macroscale sedimentological and petrophysical variations can be subtle, while biostratigraphic and seismic data may be u...
The Middle Triassic Sunset Prairie Formation has been recently identified between the Lower Triassic Montney Formation and the Middle Triassic Doig Formation in the Western Canada Sedimentary Basin. Due to its recent recognition, the Sunset Prairie Formation has yet to be incorporated into sequence stratigraphic frameworks of the Triassic. Through...
Stress-induced fractures in wellbore cement can form high-risk pathways for methane or carbon dioxide leakage yet little to no quantitative information on the impact of these fractures has been reported. To investigate this, scanning electron microscopy (SEM) and micro computed tomography (micro-CT) techniques were utilized to quantify the 2D and 3...
This paper documents aeolian and shallow‐marine interactions and describes their ichnofossil suites from the early Permian Tinat Member of the Nuayyim Formation of subsurface Saudi Arabia, thereby confirming marine sedimentation in an interval historically interpreted as being dominated by continental settings wherein aeolian processes prevailed. T...
The Nuayyim Formation of the Unayzah Group is widespread in subsurface central Saudi Arabia and constitutes a laterally variable stratigraphic unit with a complex mosaic of facies. Sedimentation for the Tinat Member took place majorly in a continental setting dominated by aeolian processes that resulted in dunes, interdunes, ephemeral stream deposi...
Many infaunal marine invertebrates produce mucus excretions that play an important role in metal binding, authigenic mineralization and burrow stabilization. To date, only a handful of studies have characterized the functional groups that control the surface reactivity of burrow linings and backfills. This makes it difficult to place estimates on t...
The fluvio-tidal transition zone (FTZ) is sedimentologically and ichnologically complex, encompassing variable sedimentary facies. Published research on the FTZ implies a wide range of physical and chemical conditions as well as resultant sedimentary structures. Variable definitions and terms have been applied to this transition zone for decades. T...
A poster presented in Goldschmidt Conference 2011 in Prague, Czech Republic. Provides preliminary/complementary results and discussion to DOI: 10.1016/j.chemgeo.2015.03.017
Public concern is heightened around flowback and produced water (FPW) generated by the hydraulic fracturing process. FPW is a complex mix of organic and inorganic solutes derived from both the injected hydraulic fracturing fluid and interactions with the subsurface lithology. Few studies to date have systematically investigated the composition of F...
Sedimentation in the Nuayyim Formation across subsurface central and eastern Saudi Arabia has been chiefly ascribed to continental sedimentary environments. However, a number of levels in this formation show evidence for marginal-marine and shallow-marine sedimentation. This paper documents trace-fossil faunas and sedimentological characteristics f...
The middle McMurray Formation is a stratigraphic unit of great economic interest in northeastern Alberta (Canada), and has been extensively studied by academics and industry alike. The paleoenvironments represented by the middle McMurray Formation have been actively debated within the last few decades. Two current interpretations of its paleodeposi...
The 2.1‐billion‐year‐old (Ga) Francevillian series in Gabon hosts some of the oldest reported macroscopic fossils of various sizes and shapes, stimulating new debates on the origin, evolution and organization of early complex life. Here, we document ten representative types of exceptionally well‐preserved mat‐related structures, comprising “elephan...
The mechanisms underpinning the deposition of fine-grained, organic-rich sediments are still largely debated. Specifically, the impact of the interaction of clay particles with reactive, planktonic cyanobacterial cells to the sedimentary record is under studied. This interaction is a potentially major contributor to shale depositional models. Withi...
Supplementary Figures from: Playter, T. , Corlett, H. , Konhauser, K. , Robbins, L. , Rohais, S. , Crombez, V. , Maccormack, K. , Rokosh, D. , Prenoslo, D. , Furlong, C. M., Pawlowicz, J. , Gingras, M. , Lalonde, S. , Lyster, S. and Zonneveld, J. (2018), Clinoform identification and correlation in fine‐grained sediments: A case study using the Tria...
In marginal marine settings, understanding the role that clay minerals play in the transfer of metal cations from the water column to the seafloor is important if the composition of modern muds is to be used as a proxy for the precursors of ancient shale deposits. In this study, we conducted potentiometric titrations of three naturally abundant cla...
Revised lithostratigraphic correlations reveal that the current stratigraphic nomenclature for the Middle Triassic within the subsurface of the Western Canada Sedimentary Basin needs modification. This paper introduces a new formation, the Sunset Prairie Formation, for an interval of interbedded light grey, pervasively bioturbated sandstone and dar...
Deposited immediately following the Montney lowstand turbidites, the moderate porosity and low permeability siltstones of the Montney D1 and D2 horizons are important exploration targets. Eight lithofacies are identified, based on detailed sedimentological and ichnological observations. Deposition took place in the distal offshore to offshore-trans...
Between the Lower Triassic Montney Formation and the Middle Triassic Doig Formation, there is an unconformity-bound interval recently identified as the Sunset Prairie Formation which occurs on a regional scale within eastern British Columbia. The interval is Middle Triassic in age and is characterized by interbedded light grey, pervasively bioturba...
Horizontal and inclined U-shaped trace fossils are commonly associated with the Cruziana and Glossifungites ichnofacies, but have rarely been described as a component of the Teredolites ichnofacies (xylic substrates). This study provides several examples of morphologies of Glossifungites saxicava from the Campanian Sunnyside Coal (Blackhawk Formati...
This paper provides an overview of the history of ichnology from both Russian and international perspectives. However, the main purpose of the paper is to review how trace fossils can be used to discern the brackish-water sedimentary environments from their open-marine counterparts. A number of modern studies are presented, including: (1) Kouchibou...
Banded iron formations are economically important sedimentary deposits in Earth's Precambrian rock record, consisting of alternating iron-rich (hematite, magnetite, and siderite) and silicate/carbonate (quartz, claylike minerals, dolomite, and ankerite) layers. Based on chemical analyses from banded iron formation units of the 2.48 Ga Dales Gorge M...