GLOSSARY

Backswamp. • SOILS "...clayey, poorly drained backswamp soils occupy distal floodplain depressions and slow and continuous sedimentation produces thick cumulative profiles." (Aslan and Autin, 1998) • SOILS "...backswamp Vertisols do not show progressive changes over time that correlate to the changes observed in the meander-belt soils." (Aslan and Autin, 1998)

Backwater. • "Where rivers near the coastline, the receiving basin begins to influence flow, and gradually varied, nonuniform flow conditions arise. The section of the river affected by nonuniform flow is typically referred to as the backwater segment, and for large lowland rivers, this portion of the river can extend many hundreds of kilometers above the outlet." (Nittrouer et al., 2012, GSA Bull)

Bank failure. • FLUVIAL “Bank failure is a common phenomenon in rivers, which commonly starts by subaqueous flow from the base of an oversteepened bank. This is followed by complete bank failure by shear along one or more discrete curved surfaces (slumping) and/or partial to complete liquefaction of bank material (Turnbull et al., 1966). Liquefaction may be spontaneous, or it may follow slumping (Lowe, 1976b). The vertical dimension of the failed mass is normally equal to the height of the original bank, but it may be greater in the case of base failure (Terzaghi and Peck, 1967). According to Laury (1971), failure occurs mainly at flood stage because of bank steepening by river bed scour and because water saturation of bank sediments increases their density and decreases shear strength due to elevated pore pressure. Falling stage exacerbates this situration by withdrawing the support of water in the channel, and by concentrating bank seepage along potential slip surface (Costa and Baker, 1981).” (Rust and Jones, 1987)

Port Sulphur bank failure, lower Mississippi River (Tobin and Jones, 2005)

Bar • DEFINITION "A bar is one or more genetically related and systematically stacked lateral accretion sets bounded by surfaces of erosion or discordance and their correlative conformities. As viewed in dip section, a bar is composed of a series of lateral accretion sets separated by erosional surfaces that persist from the surface downward toward the former channel thalweg." (Nardin et al., 2012) • DIMENSIONS "The aggregate thickness of a bar at any point is equivalent to that of the full point bar succession.

Bed "...the stratum that reveals the principal rock layering" (Campbell, 1967)

Bedload convergence. • COLUMBIA ESTUARY (DELTA) “Most of the medium to coarse sands entering the system from the river are permanently retained within the energy flux divergence (EFD) minimum. Much of this deposition takes place upstream of the limits of salinity intrustion and is not, therefore, related to baroclinic circulatory effects. Most of the fine sands and the silts and clays entering the system are not permanently retained. Some of the silts and clays are, however, temporarily retained in a turbidity maximum, whose mean position is near the lower end of the EFD minimum. This position is dictated by the inability of salinity intrusion to extend up the fluvial potential energy gradient.” (Jay et al., 1990)

Bedset "a bedset consists of a number of superimposed, similar beds" (Campbell, 1967)

Breccia. • DEFINITION "The term breccia and brèche are thought to come from the vocabulary of a medieval warrior (it means break in the wall of a fortification), but were soon adapted by the Italian and French quarrymen and builders to designate striking, fragmental stones." (Laznicka, 1989) • DEFINITION "Breccia, from the Italian word briccia, a crumb or fragment. This is a mixed stone...formed of the ruins of the primary mountains, of irregular worn pieces of silex, united by a common cement." (de Foucroy, 1789). Translated from French text • MUD CLAST BRECCIA IN OUTCROP "The only significant shale components in the thick- bedded facies [in the McMurray Fm] are in the form of intraclast breccias, which, at most, constitute up to a few per cent of the total facies. The breccias consist of angular clasts of laminated silt and clay, set in a matrix of fine grained sand. Normally, the intraclasts are 2– 20 cm across an a few centimeters thick, but blocks up to 1.5 m are present locally." (Mossop and Flach, 1983) • BRECCIAS AT MUSKEG RIVER MINE “Occasionally, [mudstone clast] breccia deposits [in the McMurray Fm at Muskey River Mine] mark the bottom of the channel sequence. Breccias consist of mud fragments incorporated into coarse sand matrix.” (Fustic, 2007) • THIN BRECCIA LAYERS IN HIS, SYNCRUDE MINE “The IHS mudstone beds [at the Syncrude mine] are discontinuous, and bed lengths are disrupted by numerous scours that are commonly lined with matrix-supported mudstone clasts. Clasts are typically angular and tabular in shape, with thicknesses, compositions, sedimentary features, and ichnofacies identical with the associated in-place mudstone beds and were clearly derived from them.” (Nardin et al., 2012, p. 287) • THICK BRECCIA LAYERS AT SYNCRUDE MINE “Lithofacies associated E (LA-E) is characterized by relatively thick interbeds of mudstone clasts commonly supported by a sand matrix…Clast shape ranges from angular to subround. Tabular clasts are by far the most common type observed in outcrop and, like LA-C clasts [i.e., mudstone breccias in the IHS], have sedimentary characteristics identical with associated in-place mudstones. Clast sizes range from millimeter to meter scale and mainly reflect the thickness of the mudstone beds from which they were derived. The fabric of the clast beds is variable, reflecting clast origin and mode of deposition. Tabular clasts were mostly oriented parallel to bedding or, rarely, imbricated. The shape and size of these clasts and their similarity to underlying mudstones indicate that they were derived from erosion of lateral accretion deposits and not transported long distances. Randomly oriented clasts may have been the products of debris flows.” (Nardin et al., 2012) • LOG SIGNATURE Mudstone breccia layers at the Syncrude mine are “…depicted by a serrated gamma-ray profile that is indistinguishable from interbedded sands and mudstones. However, this facies can be identified with dip meter logs by high-angle dips (up to 40°) and abrupt dip and azimuth changes at the decimeter to meter scale.” (Nardin et al., 2012) • BASAL CONTACT & FACIES ASSOCIATION Breccia at the Syncrude mine is “…typically bounded below by scours and is observed as interbeds in association with LA-A [dune trough cross bedded sand] and LA-C [current ripple cross-stratified sand]” (Nardin et al., 2012). • THICKNESS “Mudstone clast breccia units [in the McMurray] are variably thick, ranging from single mudstone clast lags (<0.1 m thick) to amalgamated units exceeding 5 metres thick.” (Hein et al., 2000) • LATERAL EXTENT “Breccia units [in McMurray Fm] generally have limited lateral extent…” (Hein et al., 2000) • LATERAL EXTENT “In outcrop Facies 7A is most often laterally discontinuous (over a few metres) present as thin lenses or less commonly cound in small cut and fill features.” (Hein et al., 2000) • BOUNDING SURFACES Breccia units iin McMurray Fm generally “…have an erosional base; and generally a transitional top.” (Hein et al., 2000) • COAL “Coal detritus and mummified logs may occur within breccias [in McMurray], or comminuted organics may occur throughout the sandy matrix.” (Hein et al., 2000) • POROSITY & PERMEABILITY “Porosity and permeability values are quite variable within this facies and, in core and outcrop, ‘water shadows’ within otherwise bitumen saturated zones may occur in the lee of the mudstone clasts.” (Hein et al., 2000) • FACIES ASSOCIATIONS Breccia units in the McMurray “…often underlay or interfinger laterally with the inclined heterolithic sands of Facies 10A and is commonly interbedded with [dune cross-stratified sand]” (Hein et al., 2000) • ORIGIN “The collapse of a channel bank due to natural processes such as undercutting provides both the source of the mud clasts and the required shock for the loss of the grain cohesion associated with liquefaction. Liquefaction is interpreted to be the key mechanism producing structureless sand and mud clast breccias.” (Bagdan, 2005) • BRECCIAS IN THICK-BEDDED SAND FACIES "The only significant shale components in the thick-bedded facies are in the form of intraclast breccias, which, at most, constitute up to a few per cent of the total facies. The breccias consist of angular clasts of laminated silt and clay, set in a matrix of fine grained sand. Normally, the intraclasts are 2–20 cm across an a few centimeters thick, but blocks up to 1.5 m are present locally." (Mossop and Flach, 1983) • EXPERIMENTS ON MUDCLAST TRANSPORT “From durability experiments, Smith (1972) concluded that angular mud clasts indicate little or no transport Clasts become rounded after transport in the order of tens to hundreds of metres. Further transport leads to complete disintegration.” (Bagdan, 2005) • BARRIER TO FLOW? “Mud clast breccias are not barriers to steam flow using SAGD methods. In a pilot study on the Sunrise Thermal Project Lease, oil recovery from breccias was equal to the non-brecciated surrounding sands…Bank collapse breccias must be included in evaluation of pay.” (Bagdan, 2005) • IDENTIFYING BRECCIAS IN LOGS “Localized bank collapse breccias cannot be reliably distinguished from regionally continuous stratified shale intervals using well logs along…Visual examination of core can differentiate the two facies.” (Bagdan, 2005) • CHANNEL BASE LAG “Log casts, carbonized plant debris, and shale fragments are locally abundant in the sandstone just above the contact.” (Beutner et al., 1967)

Conceptual model of channel body sandstone with channel-base mudstone clast lag, Pennsylvanian Kittanning Fm of the Alleghany Group, Pennsylvania (Beutner et al., 1967).

Chute channel

Dredging and revetment of Choctaw bar, Mississippi River, to improve navigation (Julien and Vensel, 2005). Note that similar, natural variations may have gone on in the McMurray fluvial system, leading to increase and decrease of main-channel depth over time.

Clast-supported

Conglomerate

Cut bank. • MCMURRAY FM In the Muskeg River mine, “...measured dips along interpreted cut bank side of mud-filled channel were up to 35°, versus recorded 5–25° on meandering channel side (lateral accretion).” (Fustic, 2007) • CUTBANK EROSION “Erosion of streambanks is a combination of (1) lateral erosion of the bank toe by fluvial entrainment of in situ bank materials, often termed hydraulic erosion; and (2) mass failure of the upper part of the bank due to gravity failure.” (Langendoen and Simon, 2008) • BANK STABILITY “Bankline stability [in the Brahmaputra River] is very dependent on the behavior of the river bed during flood stage and the subsequence fall of the river.” (Coleman, 1969) • BANK FAILURE “The process of bankline recession [on the Brahmaputra River] can be attributed to two major types of failure, (1) liquefaction and flowage of material and (2) shearing away of bank materials. These types are generally related and occur on differing magnitudes. Flowage failures can either occur below the water level (subaqueous) or in the zone between high water level and low water level. Below the stratified silts and silty clays of the natural-levee deposits are quite massive channel sands and silts. During flood, a greater water pressure is applied to these sands below the river level, forcing water into the formation. Evidence of this can be seen from the water tanks in the adjacent floodplains. In many cases, during the flood the water level in these tanks rises to an appreciable level and remains there until falling stage. The forcing of water into the formation raises the pore pressure in the strata. As the water level in the river falls rapidly and the pressure against the channel walls is lessened, the water moves from the formation back into the river. This cases a lateral flowage of sand and silt into the channel, resulting in subaqueous failure. This normally produces a bowl-shaped shear failure in the overlying cohesive natural-levee deposits. This type of shear failure, however, is rather imited in extent, and quite often the overlying natural-levee sediments simply fracture into numerous small blocks and tilt over into the channel…A second type of flowage failure, and one which is closely related to subaqueous flows, occurs in the upper bank and natural-levee materials. Because of the braided nature of the river channels and the constant migration of the river, many abandoned channels intersect the modern bankline. This gives rise to zones of well sorted silts and fine sands which are localized in abandoned channel fill.

Dune [compound]. (syn: sandwave) • SANDWAVE “The term sandwave is commonly used to refer to flow-transverse bedforms which are sufficiently large to have megaripples superimposed on them.” (Dalrymple, 1984) • LEE FACES “Erosion of the brink region [of the compound intertidal sandwaves in Bay of Fundy] during the subordinate tide reduces the inclination of flood sandwave lee faces at low tide to 16° on average. During the dominant tide, the upper part of the lee face may become the site of renewed deposition and often approaches the angle of repose. The lower portions of these slopes remain at a lower angle however (average 7°).” (Dalrymple, 1984)

Migration rates for compound dunes (“sandwaves”) on large tidal bars in the Bay of Fundy (Dalrymple, 1984). (B) is for a flood dominated sandwave at Economy Point. (C) is for a ebb dominated sandwave at Five Islands. Rates were measured at two stations for both (B) and (C), each 3–5 m apart along the sandwave crest. High rates of migration occur when superimposed dunes deliver sediment to the lee sandwave face; they are less clearly related to the neap–spring tidal cycle. Note average migration distance per tidal cycle is about 10 cm (ranges from several cm to 1.5 m).

Example of compound dune cross-stratification, Bay of Fundy (Dalrymple, 1984)

Ebb-oriented compound dunes, main channel of tide-dominated Bahia Blanca estuary, Argentina (Gomez et al., 2009)

Dune [migration rate]. • RHINE RIVER “…for the one occasion for which there are data, the celerity of small dunes (H = 0.1 m; L = 1.0 m; chord = 2 m; moving over gravel lag upstream of large dune) was estimated from video film as 1–3 mm/s. This was two orders of magnitude faster than the average celerity of the large dunes (3 m/day; 0.0035 mm/s) and caused the large dune to steepen over a few days (H = 0.4 m → 0.7 m; L = 36 m→ 25 m).” (Carling, 2005)

Celerity of dunes, Rhine River (Carling, 2005)

Dunes [simple]. • REACTIVATION SURFACES “Observations at low tide and echo sounder records at other times...show that the megaripples [dunes in the outer Bay of Fundy estuary] reverse at least partially with each reversal of the tidal currents.” (Darlrymple, 1984) • BYPASSING SAND “The two laboratory studies show that commonly 30–60% of all sand moving over fully developed dunes is not deposited on slip faces. Measurements from the North Loup River reveal that of all sediment moving over the dune crests there, roughly 45% is not being captured on lee faces even though 99% of sediment is transported within 2 cm of the bed.” (Mohrig and Smith, 1996) • DUNE HEIGHT “...there is a general tendency for [dune height] to increase as current speed (and depth) increase from neap to spring tides (and vice versa)...” (Dalrymple and Rhodes, 1995) • DUNE CROSS-SET THICKNESS “The preservation ratio for the [current] ripples [generated in the lab] is about 0.5, whilst measured dune heights [in the Rio Grande River] give a preservation ratio of about 0.12.” (Paola and Borgman, 1991)

Simple sketch illustrating why larger dunes tend to generate larger cross-sets (Paola and Borgman, 1991)

• DUNE CROSS-SET THICKNESS “Bedforms generated at flood stage in a river have little or not chance of full preservation in the stratigraphic record because of modification during falling stage.” (Rust and Jones, 1987) • SEASONAL DUNE MIGRATION—MISSISSIPPI BACKWATER ZONE “...translating dunes [in the backwater zone] were observed for the lowest water discharges surveyed. This indicates that reach-scale dune fields are in active motion throughout the typical annual discharge cycle in the tidal section of the Mississippi River. Previous studies from the estuarine Venice survey area (e.g., Gller and Allison, 2008) indicate dune motion ceases during low-water discharge, as bedforms are mantled with ephemeral mud deposits...We suggest that during this time, bedload transport is negligible because of the low (landward) water velocities in the saline bottom layer. In contrast, the April 2004 data show bedform transport rates that are comparable to our upriver study sites, suggesting that in the absence of estuarine circulation, tidal alteration of river vellocities has a limited impact on dune migration.” (Nittrouer et al., 2008)

River Dune migration Discharge Reference rate Dutch Rhine. Above 40–60 m/day High flow stage (5 x mean annual Wilbers and ten tidal limit at all discharge) Brinke (2003) times. <5 m/day Low flow stage (approximately mean annual discharge conditions) Mississippi (reach 0 m/day Low flow stage (Landward flow Galler and affected by seasonal was occurring along bed due to Allison (2008) estuarine circulation pronounced estuarine circulation. below Venice, Mud drape deposited.) Louisiana) >0 m/day High flow stage (Estuarine Nittrouer et al circulation destroyed. Low-flow (2008); Galler stage mud eroded.) and Allison (2008) Mississippi (tidally >0 m/day High and low flow stage (i.e., Nittrouer et al influenced reach dunes migrated year round) (2008) above reaches affected by estuarine circulation)

Epsilon cross-stratified facies [McMurray]. See inclned heterolithic stratification.

Flocculation. • SALT FLOCCULATION "...in both fresh and salt water, interparticle attraction and repulsion operate simultaneously. The attraction is independent of salt concentration, but the repulsion decreases with increasing salt concentration. In fresh water the repulsion dominates and the sol [i.e., suspension] is stable; in salt water the repulsion is reduced to the point at which the attraction begins to dominate, and the sol [i.e., suspension] flocculates." (van Olphen, 1963, p. 12) • HUMBER ESTUARY “...slow currents at slack water resulted in increased flocculation, greater sizes and enhanced settling...” (Uncles et al., 2006) • EXPERIMENTAL RESULTS “In general the degree of aggregation, and thus deposition, increased with salinity and with solids concentration. Solids concentration had by far the greatest effect on aggregation and deposition rate” (Bale et al., 2002)

Flood [fluvial].

Dunes formed in the Rhine River during a major (100-year) flood (ten Brinke et al., 2001).

Deposits of the 1998 and 1995 floods, Rhine River, about 75 km from the coast (ten Brinke et al., 2001). Cores are ~1.1 m long.

Aerial view of the Mississippi River before and after the 1993 flood (Julien and Vensel, 2005)

Dunes on the floor of the Mississippi River during high flow stage (A) and low flow stage (B) (Nittrouer et al., 2008). Note the lack of dunes in the thalweg. These areas consist of highly consolidated, relict peat and mud that form part of the older, underlying fluvial–deltaic strata.

Flood dominance [tidal currents] • BAY OF FUNDY “In general, the flood is 1.0–1.5 hr shorter in duration than the ebb due to the asymmetry of the tidal wave, and maximum flood speeds tend to be higher than those of the ebb throughout much of the area. Locally, however, ebb speeds are higher. Because of these differences, virtually all areas experience a residual transport of sediment in the direction of the faster, or dominant, current. These transport dominances are faithfully reflected in the permanent asymmetries and net migration directions of the sandwaves. Areas of ebb and flood equality, and symmetrical sandwaves, are restricted to narrow zones between adjacent ebb- and flood-dominated regions.” (Dalrymple, 1984) • NUMERICAL MODELLING “...strongly tidal estuaries of the shape considere here will transport fine sedimens upstream via nonlinear tidal rectification terms. This process will be limited either by the absence of corresponding bed sediments for resuspension or by the counteracting influence of river flow toward the tidal limit.” (Prandle, 2004)

Fluid mud • DEPOSITS “Delo (1988) refers to approximately 80 g/l as the concentration at which a bed begins to form in a laboratory settling column, whereas a range of 50–100 g/l is given by Whitehouse et al (2000). As the concentration of the settling stationary suspension increases, the effective settling velocity of the constituent flocs progressively decreases, due to hindered settling. The velocity eventually becomes zeo at the suspension gel concentration, which is the suspended particulate matter concentration at which a space- filling network of fine sediment is formed through the flocculation mechanisms...A considerable time, several hours to days (Delo, 1988), may therefore be required for these suspensions to consolidate.” (Uncles et al., 2006) • FLUID MUD FLOW “...an underwater suction system was installed in the Harbour of Leer towards which the fluid mud will flow along both of the 1000 m long harbour basins at a gradient of 1:1000” (Wurpts, 2005) • LONGITUDINAL ADVECTION “Once fluid mud is formed, Kirby (1986) found in both Severan and Rhine estuaries, the “...mode of emplace of the cohesive sediment is predominantly by longitudinal advection of dense, high concentration layers and not by vertical deposition from dispersed suspensions.” Thus, his work supports the findings of, among others, Einstein (1941), Allersma et al. (1966) and Kendrick et al., (1985), that near- bed, high concentration layers can be advected without becoming mixed with the lower concentration mobile suspension above it.” (McNally et al., 2007) • EROSIONAL SHEAR STRESS “From Mitchener and Torfs (1996), it is known that a sand:mud ration of 50 wt% can raise the erosional shear stress by a factor of two.” (Papenmeier et al., 2014) • JAMES ESTUARY “The total mass of sediment stored in the fluid mud deposits amounts to about 8.2 M tons, which is equivalent to 4.8 years of sediment input from the river.” (Nichols, 1984) • SEVERN ESTUARY “The regional distribution of mobile [fluid mud] suspensions shows a suspended solids from located along the main channel axis with the more turbid water on the southern, English, side. At maximum current velocities on spring tides, vertical suspended sediment profiles are homogeneous. As velocity decreases, a stepped structure develops due to settling, which is then remixed on the next accelerating semidiurnal tidal phase. Over the lunar timescale these steps become more stable, eventually settling to the bed. The steps are unrelated to salinity, temperature, grain-size, or mineralogy. On neap tides, layered, acoustically detectable stationary suspensions, which occasionally consolidate to form settled mud, develop from the mobile suspensions.” (Kirby and Parker, 1983) • DUNE TROUGH MUD IN WESER ESTUARY “Fluid mud formed [in dune troughs] during stage III and remained undisturbed for at least 2 h during stage IV and stage V, while turbulence was considered to be dampened at the lutocline. The onset of entrainment at the beginning of stage VI thus confined the time period of consolidation. Concerning self-weight consolidation of flocculated mud, Been and Sills [1981] conducted a settling column experiment under conditions comparable to those of fluid mud in dune troughs. Starting with a concentration of approximately 100 g/L and a height of 1.75 m, after 2 h, a layer of 0.1 m in thickness formed at the bed with a concentration exceeding 280 g/L. Accordingly, the formation of a thin, higher concentrated mud layer at the river bed is considered to be highly probable. This layer may be sufficiently resistant to erosion to survive the initial part of the entrainment phase and mixed or even covered by sand as a result of bed load transport and leeside deposition.” (Becker et al., 2013) • SPRING VS NEAP – COLUMBIA ESTUARY “The large stratification and resulting weak boundary shear stresses on low-flow neap tides allow the temporary settling out of fine grained material throughout the lower estuary. This same deterioration of the turbidity maximum has also been observed on low-flow neap tides in the Gironde Estuary (Allen et al., 1980)...” (Jay et al., 1990) • SPRING VS NEAP – GIRONDE ESTUARY During spring tides, sediment in the turbidity maximum “...is dispersed in upper layer and advected seaward. During neap tides most sediment stays near the bed, where it is subjected to net landward drift.” (Castaing and Allen, 1981). See figure below.

Neap–spring variations in the turbidity maximum in the Gironde Estuary (Castaing and Allen, 1981)

Hindered settling • DEFINITION “When the concentration of sediment particles increases, particles cease to behave independently. Instead, their motions are correlated through hydrodynamic and particle–particle interactions, often resulting in settling rates that are lower than that for individual, isolated particles (i.e., hindered settling).” (Culbertson et al., 2009)

Hot vs warm water bitumen extraction. • “In the hot water extraction process, the oil sand–water slurry temperature is kept at ~80– 82 °C by mixing mined oil sand with hot water and steam addition. The warm water process is a variation of the classical hot water extraction process in which, to reduce costs, the slurry temperature is below 55 °C, the highest temperature that can be reached in a continuous process using only hot water, with no steam addition.” (Czarnecki et al., 2005)

Hyporheic zone. • DEFINITION “The hyporheic zone is the region in unconfined, near-stream aquifers where stream water is present, including zones where stream water is mixed with groundwater.” (Wondzell and Swanson, 1999) • ORIGIN “The hyporheic zone is created by flows of surface water into the subsurface and eventual return flows to the stream. These flows, called exchange flows, are driven by head gradients created by morphological features of stream channels.” (Wondzell and Swanson, 1999) • FALLING STAGE AND BANK FAILURE “In many rivers bank slumping is most common during falling stage, as highly saturated sediments are more prone to cave than less saturated sediments. This holds true to some degree in the Brahmaputra, but equally important is the shifting of the current. When the flow approaches the bank at some slight angle, severe undercutting takes place and the overhanging sediments slump. This changes the relationship between the thread of the current and the new bankline, and the process will be repeated again at some place downstream. This process is continuously repeated during the rising stage and leads to large scale movements of the bankline. Smaller slumps that result from the rapid withdrawal of water during falling stage increase the rate of bankline retreat after passage of the flood…Thus there are two types of slumping which cause the bankline to recede, one operating during flood stage (undercutting) and the other during falling stage (flowage of highly saturated sediments).” (Coleman, 1969).

Inclined heterolithic stratification [McMurray]. • SEDIMENTOLOGY "The uppermost beds of the thick-bedded sand facies transitionally grade into and interdigitate with the [thick bedded sand facies] beds at the base of the overlying epsilon cross-set. In the field, this relationship can be documented by tracing groups of sand beds down the epsilon slope through a transition zone where the mud partings between the beds die out and the zone assumes a thick-bedded aspect. The uppermost thick beds of the lower unit are in part characterized by large-scale cross-bedded sand, but are normally dominated by current rippled sand similar to that in the sand beds of the epsilon cross-strata. Parallel laminated sands are also present in the transition zone between facies." (Mossop and Flach, 1983) • PALEOFLOW "Directional data derived from outcrop measurements of ripple foresets in the epsilon cross-stratified facies as well as trough axes in the underlying thick-bedded facies indicate a moderately well-defined pattern of unidirectional paleocurrent transport towards the north-west, in the direction of the Boreal Sea. These data assume their greatest significance, however, when plotted relative to the depositional strike and dip of the epsilon cross-set with which they are associated. Figure 10 reinforces what is subjectively obvious in the field—that paleocurrent indications are strongly unidirectional, approximately parallel to the depositional strike of the associated epsilon cross-set." (Mossop and Flach, 1983)

Mudstone bed length in IHS in McMurray Formation, Syncrude mine (Nardin et al., 2012)

Inland swamp. • "Deposits of the inland swamp environment [of the Mississippi River delta plain] consist of organic clays and woody peats. Because of ubiquitous subsidence, the thickest deposits occur in the older delta complexes and attain maximum thicknesses of about 20 ft." (Saucier, 1994)

Intertidal mudflat channels. • WIDTH–DEPTH RATIOS “The majority of the channels [studied on Scottish mudflats] have width/depth ratios between 4 and 10, which are characteristic of meandering fluvial channels.” (Bridges and Leeder, 1976) • ROTATIONAL SLIDES ON PB “The lower limit of width/depth ratio is a response to the development of rotational slides on the point bar slopes of narrow, deep channels (W/D < 5). These slides tend to increase channel widths rapidly. They also occur on the cut banks of channels deeper than 1 m.” (Bridges and Leeder, 1976) • ROTATIONAL SLIDES ON CUTBANK “Channel erosion, usually concentrated on the outside of meander beds, occurs in response to three mechanisms [direct fluid stress, waves, and rotational slides]...Rotational slides are particularly important erosive mechanisms in larger channels. They occur on the cut-banks of channels with width/depth ratios of <5. There is no preferred location of these slides around the channel perimeter.” (Bridges and Leeder, 1976) • MEANDER WAVELENGTH “There is a poor correlation of meander wavelength to both width and depth.” (Bridges and Leeder, 1976) • SEASONAL INFLUENCE “Enhanced ebb currents due to increased runoff discharge by heavy [summer] precipitation accelerated point bar migration [on the Yeochari open-coast tidal flat in Korea by up to 40 m per month]. Remarkable rill erosion induced by heavy precipitation especially during low tide led to rapid accumulation of sediment at the lower part of the point bar and channel base [up to 40 cm per month], creating a convex-up point bar geometry. Present study illuminates the fact that the stratigraphic architecture of IHS of intertidal origin [on open coast tidal flats in Korea] is largely controlled by monsoonal climate change rather than tidal process even in the macrotidal environment.” (Choi et al., 2013)

Rapidly deposited (up to 40 cm per month), fluid mud on lower point bar of intertidal mudflat channel, Yeochari tidal flat, Korea (Choi et al., 2013).

Karst. • DEFINITION “The term karst signifies a landscape with characteristic surface morphology, subsurface drainage, and collapse features which are specifically developed on rocks, mainly limestones, which possess a higher degree of solubility in natural waters than other types…” (Wright, 1982) • TYPES “There are basically two types of paleokarsts encountered by geologists working in ancient sequences: paleokarstic surfaces and subsurface paleokarst. The former represents solution which took place at the atmosphere–rock interfact (uncovered karst…), at the soil– rock interface (covered karst…), or at the water–rock interface. Subsurface paleokarsts (caves, etc.) have resulted from solution caused by underground drainage, and such features often attract attention because of the deposits they contain.” (Wright, 1982)

Lamina "...the smallest megascopic stratum" (Campbell, 1967)

Laminaset "a laminaset consists of a group of conformable laminae that form a distinctive structure within a bed" (Campbell, 1967)

Lateral accretion set. • DEFINITION "A lateral accretion set is one or more genetically related and systematically stacked stories bounded by surfaces of erosion or discordance and their correlative conformities." (Nardin et al., 2012) • DIMENSIONS "At Syncrude's north pit, lateral accretion sets are 5 to 20 m thick and extend the dip length of the point bar surface. They are the smallest units that would be potentially resolvable with high resolution seismic data...For IHS dip angles averaging 9, lateral accretion sets would have plan view widths ranging from 30 to 130 m, which are similar to the scroll widths observed on the time slices." (Nardin et al., 2012)

Levees • DESCRIPTION “[Fluvial] levees are discontinuous, wedge-shaped ridges around active and abandoned channels.” (Bridge, 2003) • HEIGHT “[Fluvial] levees vary in height above the adjacent flood basin by up to a few decimeters or meters, depending on river size, grain size or the river’s sediment load, deposition rate, and stage of development.” (Bridge, 2003) • WIDTHS “Widths of [fluvial] levees are up to about four channel widths.” (Bridge, 2003) • TIDAL CREEKS “Levees are often well developed in fluvial systems, where sudden dumping of sediment occurs as current velocities rapidly attenuate on leaving the main flow. In marsh [tidal] creeks, velocities are already low when bankful stages are attained. When present, marsh levees display less striking grain-size contrasts with adjacent overbank surfaces. They are composed primarily of mud trapped by the baffling effect of Spartina which grows more luxuriantly along the bank crests.” (Barwis, 1978)

Low-flow stage

The Mississippi River near Memphis on August 12, 2012, during a historic drought when river stages dropped to their lowest level in over 20 years (Nittrouer and Viparelli, 2014). Note the inactive dunes in the exposed channel. This image, which was taken ~1200 km from the coast and hundreds of kilometers above the tidal limit, demonstrates the seasonality of sediment and fluid discharge common to many rivers.

Lutocline. • DEFINITION “A lutocline is a density step structure. Vertical mixing across a density step structure is dependent on the local Richardson number.” (Wolankski et al., 1989) • LUTOCLINE “In turbid estuaries and coastal waters, the [vertical] step structure [in suspended sediment concentration] is sometimes so prominent that the water column can be divided as two fluids, namely a fairly clear upper layer and a very turbid bottom layer, the two layers being separated by a lutocline (a sharp step structure in suspended sediment concentration)....The SSC values in the bottom fluid-mud layer are often in the range of 10– 200 g/l (Wolanski et al., 1989)

Lutocline separating clear water from fluid mud, Orchard Lake, Michigan (Wolanski et al., 1989). The lutocline pictured was disturbed by a diver. Prior to this, it was a flat, horizontal surface (the diver thought it was the lake bottom). “Lutum” is latin for “mud” (Kirby and Parker, 1983).

McMurray Formation • "LARGE CHANNEL" MODEL "The subject sequence consists of three distinct facies, always present in the same vertical order (see figure below). A sharp scoured surface at the base is overlain by thick bedded sand. Gradationally overlying this facies and interfingering with it, is the epsilon cross-stratified facies. The uppermost facies, not everywhere present, comprises horizontally bedded argillaceous sand and silt. The contact between the epsilon cross-strata and the overlying argillaceous sand facies is commonly one of truncation (see figure), but transitional relationships are observable in some exposures, the epsilon beds asymptotically curving to the horizontal." (Mossop and Flach, 1983)

• ARCHITECTURE "In the rare exposures where two distinct sets are exposed together it is clear that the contact relationship of one set to the other is that of erosional truncation...[see figure below]" (Mossop and Flach, 1983)

• THICK BEDDED SAND FACIES "This facies has an erosive base and is characterized by large-scale trough cross-sets, averaging 0.5–1 m in thickness, with some sets up to 1.5 m thick and 6 m across. In the upper portions of this facies, the trough cross-beds give way to smaller-scale current structures, with climbing ripples being common." (Mossop and Flach, 1983) • LATERAL ACCRETION DEPOSITS "Sets of epsilon cross-strata average 15 m in thickness (range 8–25 m) with the surfaces dipping an average of 8°–12° (range 4°–22°). The depositional strike and dip is normally consistent in any given exposure, but adjacent exposures, only a few hundred meters apart, characteristically show wide divergence in attitude. In exposures parallel to the dip of the epsilon cross-strata, the major surfaces are planar from the top to the base of the slope. The sloping strata consist of decimeter to meter thick beds of fine- to very fine-grained sand, normally current rippled, separated by partings of argillaceous silt that are normally 2–5 cm thick and increase in abundance towards the top of the set." (Mossop and Flach, 1983)

• GRAIN SIZE TRENDS "Detailed sampling and analysis of material collected from a single outcrop indicate a distinct upward fining trend in the sequence as a whole, manifest in part by a decrease in mean sand size and in part by an upward increase in the abundance of silt and clay partings. [see figure below]" (Mossop and Flach, 1983)

• "LARGE CHANNEL" MODEL "We believe that the sequence originated as a result of the lateral migration of very deep (20–45 m) meandering channels. Epsilon cross-strata were deposited on the point bar of the channels while contemporaneous trough cross-bedded sands were deposited in the channel bottoms. The basal portions of the overlying upper unit are interpreted as representing overbank deposition associated with the channels." (Mossop and Flach, 1983) • BED CONTINUITY “…there is an extreme variation laterally, and difficulty is experienced in tracing thin beds even at 200 foot [well] centers.” (Ansley and Bierlmeier, 1963, as quoted by Flack, 1977) • LITHOFACIES “…some lithofacies that have been described in outcrop have never been encountered by mine-site geologists in thousands of subsurface drill holes or kilometers of mine faces that have been logged over the years. This indicates that there is, to a certain extent, a high degree of natural complexity to the package of units that are preserved in the Athabasca deposit.” (Hein et al., 2000) • LOWER MCMURRAY “…recognition of the Lower McMurray is usually straightforward, based on facies seen in both core and outcrop, and on geophysical logs from subsurface wells.” (Hein et al., 2000) • DEVELOPMENT PROBLEMS “Some factors that may impede [oilsands] development [in Alberta] are the regional persistance of shale breaks, the lack of continuity of reservoir sands, and the co-production of gas and bitumen zones within the same reservoir. To meet some of these challenges for development, it is imperative that the natural heterogeneity of the deposits be mapped at an intermediate and local scale.” (Hein et al., 2000) • CHANNEL SIZE “Channel size within the McMurray succession varies significantly within the oil sands deposit from thick, large single event channels to smaller scale multi event channel complexes. Stacked channels at both scales are common. Subsurface gamma ray profiles over the Upper McMurray [i.e., the tidal-fluvial stuff] often display up to three stacked fining upward successions. Channel preservation is dependent upon the degree of incision of the successively younger channel events. Channel stacking can be best verified using core, especially when eroded lateral accretion and less commonly vertical accretion deposits are partially preserved within older channel successions. In general, larger scale channels (>10 m deep) tend to be situated near the base of the Upper McMurray succession, with the smaller scale channel fills (<10 m deep) preserved higher in the section. Large channel fills tend to be sand-dominated, whereas smaller channels range from sand- to mudstone-dominant.” (Hein et al., 2000) • TRACE FOSSILS “Dominant trace fossils [in the Upper McMurray] include Planolites and Cylindrichnus, less commonly Skolithos, Teichichnus, and Gyrolithes.” (Hein et al., 2000) • ROOTS “Rooting is relatively rare and is most commonly found within the uppermost Upper McMurray sediments.” (Hein et al., 2000) • BIOTURBATION IN MCMURRAY IHS Brackish water channel fills “…contain a distinctive trace fossil suite that is commonly dominated by simple vertical burrows such as Skolithos and Cylindrichnus. Such trace fossils are commonly associatted with facies characterized by inclined heterolithic stratification that have been interpreted to represent lateral accretion point bar deposits. In the Lower Cretaceous McMurray Formation of NE Alberta, a Skolithos–Cylindrichus assemblage characterizes the inclined heterolithic stratification deposits that have been interpreted as estuarine point bars…” (Pemberton and MacEachern, 200X). See figure below.

• NEAP SPRING CYCLES See underlying figure, from Pemberton and MacEachern (200X), based on data from the Syncrude mine.

• POROSITY “Porosity in the McMurray Fm typically averages 36%” (Mohammed, AGAT Oilsands Labs, Calgary, personal communication, July 2014) • OVERBURDEN “Open pit mining is not economic where more than about 50 m of overburden must be removed” (Bagdan, 2005) • PROVENANCE “McMurray Formation sediments within the area of the Athabasca Oil Sands Deposit are generally thought to have been derived from an eastern source, most likely from the erosion of the Proterozoic Athabasca Sandstone of the Precambrian Shield (Stewart and MacCallum, 1978). The general consensus is that the initial and intermediate stages of sedimentation were derived from reworking of the Athabasca Sandstone and later sediments from the erosion of the underlying igneous and basement rocks of the Precambrian Shield (Sproule, 1951; Mellon and Wall, 1956; James, 1977). A few authors (Carrigy, 1959a; Bayliss and Levinson, 1976; Wach, 1984) have raised the possibility that another source may have been the Western Cordillera, at least during the latter stages of McMurray time.” (Bagdan, 2005) • AGE “The present consensus places the McMurray in the Aptian, possibly up to early Albian stages (Burden, 1984; Hein et al., 2000).” (Bagdan, 2005)

Meandering river. • COHESIVE BANKS “Rivers with a cohesive floodplain develop into

Mud pebbles

Rounded mud pebbles and cobbles in samples of fine to medium sand collected beneath the turbidity maximum in the Weser Estuary (Schrottke et al., 2006). These pebbles were presumably eroded from channel-base fluid mud deposits, which are also accumulating beneath the turbidity maximum.

Permeability • SURFACE AREA VS GRAIN SIZE “...the specific surface area of colloidal clay ranges from about 10 to 1,000 m2/g, which can be compared with 1 and 0.1 m2/g for the smallest particles of silt and fine sand, respectively (e.g., Whitlow, 1995)” (Uncles et al., 2006)

Pre-Cretaceous unconformity. • KARST “Local karstification of the Devonian carbonates and mineralization (including pyrite, chalcopyrite, sphalerite; less commonly barite, calcite, quartz and silica, among others) occurs along the unconformity (Abercrombie, 1988; Abercrombie and Feng, 1997; Feng and Abercrombie, 1994; Tsang, 1998…)” (Hein et al., 2000) • KARST FEATURES “Karst features include isolated sinkholes, larger depressed regions and local karst breccias.” (Hein et al., 2000) • MARLS OVERLYING KARST “Marly deposits and leached carbonate paleosols are less common along the unconformity surface. Such deposits most often occupy lows on the erosional surface…The marly lacustrine unit generally lacks bioturbation (may contain rare horizontal Planolites traces), contains carbonaceous debris, and is interpreted as alluvial in origin. Nodules along the unconformity include ironstone (siderite along with hematite)…Microfossil dating of spores and pollen grains indicate a Barremian age, in paludal, isolated swamps along depressions on the eroded limestone surface.” (Hein et al., 2000) • WEIRD SILICICLASTICS OVERLYING DEVONIAN KARST SURFACE “The lowermost units along the basal [McMurray] unconformity were incorporated [in the study] because palynological analysis indicates that some of the mixed calci-/siliciclastic units were emplaced as karst fill and colluvium along the pre-Cretaceous unconformity surface during McMurray time.” (Hein et al., 2000) • TOPOGRAPHY “There are numerous north-northwest trending ridges on the unconformity surface that correspond to subcrop edges of erosion resistant Devonian strata (Martin and Jamin, 1963). The two main ridges are the Grosmont Ridge, the northern extension of the Wainwright Ridge (Ranger, 1994), which forms the western boundary of the Athabasca Oil Sands Deposit, and the Beaver Hill Lake Ridge, which formed as a result of salt solution of underlying beds to the east of the ridge (Stewart and MacCallum, 1978).” (Bagdan, 2005)

Point bar. • WILLAPA RIVER “Point bar facies are dominated by ECS [i.e., IHS] of sand-mud couplets extending the full length of the point bar (inferred from similar looking Late Pleistocene point bar deposits exposed in a nearby cliff). Gravel and mudballs rest in erosional contact with underlying mud at the channel base. Upward, inclined sand–mud couplets contain mudballs, mud chips, mud blocks and organic litter. Bioturbation is most prevalent in the upper point bar sediments.” (Smith, 1987) • WILLAPA RIVER – GRAIN SIZE TRENDS “...mean grain size fines both upsection and downstream around a point bar...” (Smith, 1987)

Reactivation surface. • ORIGIN “No doubt these diastems result from cessation of supply around slack-water stage followed by erosion of the mega ripple front during the [subordinate] tide. The trace of the erosional surface, which progressively flattens upwards, gives the impression that the mega ripple’s top is blown off.” (Boersma, 1969) • SIGNIFICANCE Reactivation surfaces in tidally influenced dune cross-bedding commonly “…betray the existence of rather strong flood currents in an ebb-dominated area [or vice versa].” (Boersma, 1969)

Scroll bars. • TOPOGRAPHY “Point bars are major depositional bodies of meandering rivers… They have a characteristic ridge-and-swale topography, which is visible on airborne scanning laser altimetry images…and is often expressed in the distribution and succession of vegetation…The ridges are formed as scroll bars parallel to the curved channel and separated from the inner bank by a swale…The low lying swales are preferential pathways for cutoffs rather than the elevated ridges.” (van de Lageweg et al., 2014). • ORIGIN “Several studies suggested that each scroll bar is formed during one flood event (Nanson, 1980; Nanson and Hickin, 1983)…” (van de Lageweg et al., 2014) • SEDIMENT TRACER EXPERIMENTS “Sediment tracers confirm earlier findings (Pyrce and Ashmore, 2005) that sediment eroded from the outer bank upstream of the bed apex was deposited on the point bar downstream off the same bend apex. In constrast, sediment eroded downstream of the bed apex was deposited on the next downstream point bar.” (van de Lageweg et al., 2014)

Seafoam mudstone. • AGE “During this extended hiatus [between Devonian and Cretaceous], it is probable that the Devonian strata were subjected to several periods of subaerial exposure. The presence of locally observed calcareous shales directly beneath the McMurray Formation (Carrigy, 1959a; Steward, 1963) is consistent with this interpretation. These green shales are also identified in the study area. In central and southeastern Alberta, the basal calcareous shales are identified as the Deville Member. Although the Deville is siilar to the basal claystone beds of the lower member of the McMurray, it is unclear whether the two members are indeed correlative in either a genetic or time-stratigraphic sensne. Williams (1963) suggested that the Deville might represent deposits of Jurassic age. However, this remains speculative, as conclusive evidence of deposition between Devonian and Early Cretaceous time has remained elusive in northeastern Alberta…” (Bagdan, 2005)

Siderite. • ORIGIN "Most siderite...probably forms under strongly reducing conditions." (Berner, 1981) • ORIGIN “Siderite (FeCO3) precipitates in reducing pore waters in which iron reduction exceeds sulphate reduction…it is especially abundant in non-marine strata. Displacing siderite nodules are common in peaty, methanic soils that develop within poorly drained, floodplain sediments…” (Loope et al., 2012). • ORIGIN OF DETRITAL NODULES “As fluvial channels shift, these [siderite] nodules are commonly reworked into channel sands to be preserved as intraformational clasts…” (Loope et al., 2012) • ALTERATION OF SIDERITE NODULES “Because siderite is unstable in the presence of molecular oxygen, iron oxide minerals usually dominate such clasts when they are found in outcrops and in the shallow subsurface…Van der Burg called attention to the dense, iron- oxide-cemented rinds on the concretionary clasts that were studied within Quaternary alluvium of the Netherlands and proposed that the rinds formed at the perimeter of reworked, siderite-cemented soil nodules and thickened inward as siderite was progressively dissolved and ferrous iron migrated outward toward the perimeter of the concretion.” (Loope et al., 2012) • SIGNIFICANCE “… siderite is widely regarded as a diagnostic indicator of of methanic or post-oxic environments which contain little or no H2S…” (Pye et al., 1990) • IN-SITU VS DETRITAL NODULES “The concretions are best exposed where creek migration and bed scouring has caused bank collapse, along the eroded Lower Marsh front, and long the margins of major creeks on the Upper Marsh. Laminations can be traced through some concretions into the surrounding sediment, testifying to their in situ development. Reworked, partially oxidized concretions are found in the creek beds and on the surface of the sand flats.” (Pye et al., 1990) • SIDERITE NODULES IN MISSISSIPPI FLOODPLAIN SEDIMENT “Nodules [of siderite] were encountered throughout the [120 ft long] boring, but it was quite evident that those near the bottom of the core were somewhat larger and much better consolidaated than those near the top.” (Ho and Coleman, 1969) • SIDERITE NODULES AND ORGANIC MATTER “…a greater number of [siderite] nodules was noted when organic matter (rootlets and the like) or shells were present. The highest concentrations were in areas containing the highest amounts of organics” (Ho and Coleman, 1969)

Siderite nodules in modern sediments Location Sediment Nodule size Radiocarbon age of References organics in sediment Namyang Bay Mud 0.1–0.25 mm 8,600 BP Lim et al., tidal flat, Korea 2004 Ganghwa tidal Mud 0.150 mm 8,000 BP Khim et al., flat, Korea 1999 Atchafalaya Bay Fresh to brackish 1–2 cm 1300–10,000 BP Moore et al., delta plain mud 1992; Bailey et al., 1998 Youngjong– Freshwater(?) mud 0.05–0.15 8,000 BP Choi et al., Yongyou and deposited over mm 2003 Kimpo tidal flats sequence boundary Mississippi delta Delta plain mud 1–2 cm (and Holocene Aslan and plain tabular bands Autin, 1999 <5 cm thick)

Chemical environments that develop in freshwater vs marine sediments during progressive burial and resultant diagenetic minerals (Bailey et al., 1998). OXR = oxygen respiration, NR = nitrogen reduction zone, SR = sulfate reduction zone, FER = Fe–Mn reduction zone, ME-D = methanogenesis- decarboxylation zone.

Clast-supported channel-base lag of iron-oxide nodules in Cretaceous fluvial deposits, Dakota Formation, Nebraska (Loope et al., 2012). These nodules likely started out as early diagenetic siderite nodules in floodplain strata (probably formed within first few thousand years of deposition; see Aslan and Autin, 1999), then were incorporated into the channel through cutbank erosion. At a later date, they were exposed to oxygen and altered to iron oxide. I observed similar iron oxide nodules in channel base dunes in the Middle McMurray Fm at the type section on the Athabasca River this summer. I also observed rare detrital siderite nodules in Assemblage 3 channel-base mudclast breccias in the LLSW cores (although the McMurray LLSW breccias are not clast supported; rather, they are almost invariably supported by a matrix of structureless fine sand).

Slickensides [pedogenic]. • DEFINITION “Pedogenic slickensides are convex-concave slip surfaces that form during expansion/contractions in expansive clay soils…When observed in rocks, they appear similar to tectonic fault planes but are differentiated by (1) arrays of slickenlines that curve through arcs of more than 90 and are not related to know tectonic structures, (2) their presence in undeformed rocks, and (3) their restriction to paleosol horizons” (Gray and Nickelsen, 1989) • MODERN EXAMPLES “Pedogenic slickensides have been described in modern Vertisols (Grumusols) in the US Gulf Coastal Plain (Wilding, 1985); North Dakota (White and Agnew, 1969); Botswana (Watts, 1977); Sudan, Ethiopia and Chad (Young, 1976); Isreal (Yallon and Kalmar, 1978); and Australia (Knight, 1980). (Gray and Nickelsen, 1989) • ALTERNATIVE TERMS “No satisfactory geologic names for these features has evolved from their description by soil scientists and sedimentologists. They have been called compression structures or folds (Allen, 1973), slickensides (Yaalon and Kalmar, 1978), soil microrelief structures (Goldbery, 1982), pseudo-anticlines (Watts, 1977; Wright, 1982), tentlike structures (Van Houten, 1980), conical joints (Rixon et al., 1983), and slickensided cracks or slickensided shear planes (Knight, 1980).” (Gray and Nickelsen, 1989) • ORIGIN "Pedogenic slickensides in the smectite-rich backswamp soils [adjacent to the Mississippi in Louisiana] form in response to seasonal water-table fluctuations and alternative episodes of soil wetting and drying. The slickensides increase and then decrease in abundance and size with increasing soil depth, similar to pedogenic slickensides reported from soils elsewhere (Yaalon and Kalmar, 1978; Dudal and Eswaran, 1988; Wilding and Tessier, 1988). In addition, lateral changes in the depth of the base of slickensides in the backswamp profiles parallel changes in the position of the low seasonal water table. The shallow depth of the slickensides near the margins of the backswamp probably reflects a combination of shallow water table levels and the present of sand and silt, which inhibit soil shrinking and swelling." (Aslan and Autin, 1998)

Pedogenic slickensides in coaly mudstone in continental strata at the base of the McMurray Formation, Long Lake SW, Well 1AB091308507W400.

Story. • DEFINITION "A story is one or more genetically related and systematically stacked bedsets bounded by surfaces of erosion or discordance (sensu Allen, 1983) and their correlative conformities." (Nardin et al., 2012) • DIMENSIONS "...stories typically have thicknesses on the order from 1 to 5 m and may extend laterally for up to 100 m." (Nardin et al., 2012)

Stratum • "...a layer of rock or sediment that is visually or physically more or less distinctly separated from layers above and below by surfaces termed stratal surfaces." (Campbell, 1967)

Suspended sediment. • SEVERN ESTUARY “Generally speaking, the concentration [of suspended sediment in the estuary] is greater on the flood than the ebb, and larger at springs than neaps…About twice as much sediment is in suspensio during [the stormy] winter than [the calm] summer.” (Allen, 1990)

Tidal bundle. A tidal bundle, as originally defined by Boersma (1969), is • DEFINITION “

Tidal creeks. Name commonly given to small channels on intertidal mudflats. • See intertidal mudflat channels.

Tidal flat. • HIGH TIDAL FLAT MUD “Field experience here [in the Severn Estuary] over many years shows that mud can be accumulated on the high tidal flats at a rate equivalent to the order of 0.1–0.2 m annually. Sediment tends to build up during the spring and again in early autumn; in winter, the windiest season in the Severn Estuary, erosion tends to dominate.” (Allen, 1990)

Tidal–fluvial point bars • TIDALLY INFLUENCED POINT BARS “While it might be argued that the tidally influenced point bar facies located in upper and middle estuarine settings should not be classified as fluvial, two reasons can be presented for a fluvial classification. First, sand in the ECS [i.e., IHS] is thought to be deposited by fluvial floods coupled with ebb tide, though mud is thought to be deposited during low stage fluvial–ebb tidal and flood tidal flows...Second, most ECS with rhythmi sand-mud couplets in ancient rock sequences have been interpreted as fluvial in origin, though they may have been micro- and mesotidally influenced river/upper to middle estuary origin...” (Smith, 1987)

Turbidity maximum • COLUMBIA ESTUARY (DELTA) “Most of the medium to coarse sands entering the system from the river are permanently retained within the energy flux divergence (EFD) minimum. Much of this deposition takes place upstream of the limits of salinity intrustion and is not, therefore, related to baroclinic circulatory effects. Most of the fine sands and the silts and clays entering the system are not permanently retained. Some of the silts and clays are, however, temporarily retained in a turbidity maximum, whose mean position is near the lower end of the EFD minimum. This position is dictated by the inability of salinity intrusion to extend up the fluvial potential energy gradient.” (Jay et al., 1990)

Seasonal and neap–spring dynamics of the turbidity maximum in the macrotidal Humber Estuary, UK (Uncles et al., 2006)

Neap–spring variation of turbidity in the Gironde Estuary during low river flow (Dioxaran et al., 2009).

Vertisol. • CHARACTERISTICS “Vertisols are a group of soils distinguished by high amounts of shrink– swell clays; minimal horizon differentiation due to pedoturbation; pronounced changes in volume with changes in water content resulting in deep, wide cracks in the dry seasons; very plastic and sticky soil consistency when wet; and unique subsurface structure features called slickensides...” (Miller et al., 2010) • LACK OF HORIZONATION “Early pedogenic studies invoked a pedoturbation, or self- mixing, model to explain the apparent lack of horizonation in Vertisols of Texas…and elsewhere. Today, most investigators employ the soil mechanics model…to explain the preservation of systematic pedogenic depth functions and the formation of slickensides, wedge-shaped aggregates, and gilgai resulting from shear failure along stress zones.” (Nordt et al., 2004) • BEAUMONT FM, TEXAS “Nearly 4 million ha of Vertisols occur…on the Beaumont Fm along the coastal plain of Texas…The Beaumont Fm consists of meander ridge and swale topography deposited during the late Pleistocene within a large fluvial–deltaic system…Vertisols form in the broad, clayey, floodbasin facies between slightly elevated meander ridges.” (Nordt et al., 2004)

Vertisol from Texas (Nordt et al., 2004)

Wabiskaw Member (Clearwater Fm). • WABISKAW VS MCMURRAY “From a regulatory viewpoint the Wabiskaw and McMurray are considered as a single unit because of the connectivity between the two units, that are often in direct contact or later co-mingled for production…Geologically, however, these are dissimilar units, each with distinct lithologies, deposited within unlike environments of different ages (biostratigraphically-dated). Thus, the McMurray Formation rests with profound unconformity on the Devonian carbonates, and is unconformably overlain by the Wabiskaw Member (Clearwater Formation).” (Hein et al., 2000) • GLAUCONITE “Traditionally the base of the Wabiskaw Member was identified by the presence of glauconite (Badgley, 1952). Detailed stratigraphic work of the last several years suggest the base of the Wabiskaw Member is lower, especially when there is a thick Wabiscaw valley-fill succession (e.g., range of 1 to 30 m lower).” (Hein et al., 2000) • BASE OF WABISKAW “Palynological analyses of mudstones below and above the McMurray/Wabiscaw contact confirms a change in environment from brackish to fully marine; and a significant difference in ages.” (Hein et al., 2000) • GLAUCONITE VS CHLORITE “…the McMurray–Clearwater contact has been identified by other researchers as a distinct colour change in shales from brownish gray in the McMurray to a glauconite-induced, dark bluish-gray in the Wabiskam Member of the Clearwater Formation…However, petrographic analysis has found this practice to be false. The mineral responsible for the blue-gray color is chlorite [no reference cited for this observation].” (Bagdan, 2005)

Water-wet.

REFERENCES Bagdan, C. 2005. Stratigraphy, sedimentology and ichnology of the McMurray Formation, Northeastern Alberta, Canada. University of Alberta, Unpublished MSc thesis, 264 p. Bridges, P.H. and Leeder, M.R. 1976. Sedimentary model for intertida mudflat channels, with examples from the Solway Firth, Scotland. Sedimentology, v. 23, p. 533–552.

Rotational slides on the banks of a small intertidal mudflat channel, Scotland (Bridges and Leeder, 1976).

Sedimentation rates on the point bar of an intertidal mudflat channel in Scotland during a complete ebb-flood cycle (Bridges and Leeder, 1976). Ebb flow is to the left.

De Mowbray, T. 1983. The genesis of lateral accretion deposits in recent intertidal mudflat channels, Solway Firth, Scotland. Sedimentology, v. 30, p. 425–435.

Seasonal lateral-accretion packages in an intertidal mudflat channel point bar, Scotland (de Mowbray, 1983). The packages are separated by erosion surfaces generated during episodes of increased discharge associated with intense winter rainfall events. Note how these erosion surfaces are prominent in the deep channel, but lose their expression moving upward.

Deposition and erosion on the point bar of an intertidal mudflat channel, Scotland, over a period of one year (September 1977 to August 1978). From de Mowbray (1983) de Foucroy, M. 1789. Elements of Natural History and Chemistry, Volume 1 (English translation of French book). 526 p. Friedrichs, C. 2012. Hein, F., Cotterill, D.K. and Berhane, H. 2000. An atlas of lithofacies of the McMurray Formation, Athabasca Oil Sands deposit, Northeastern Alberta: Surface and subsurface. Alberta Geological Survey, Report 2000-07, 217 p. Laznicka, P. 1989. Breccias and ores. Part 1: History, organization and petrography of breccias. Ore Geology Reviews, v. 4, p. 315–344. Laurien(?) Bloom McCallum & Stewart. Syncrude consultants. Darrell Whiteman. Darrell Cotterill. Perry Gleister. Rudy Srobl.

Smith, D.G. 1987. Meandering river point bar lithofacies models: Modern and ancient examples compared in Ethridge, F. G., Flores, R. M., and Harvey, M. D., eds., Recent Developments in Fluvial Sedimentology. SEPM, Special Publication No. 39, p. 83–91. van de Lageweg, W.R., van Dijk, W.M., Baar, A.W., Rutten, J. and Kleinhans, M.G. 2014. Bank pull or bar push: What drives scroll-bar formation in meandering rivers? Geology, v.42(4), p. 319– 322.

Experimentally produced point bar deposits