This document summarizes various depositional environments including aeolian, fluvial, shallow marine/shoreline, deltaic, deep marine, and carbonates. For each environment, it describes the typical facies/depositional areas, geometries, trends, and potential reservoir and seal facies. The environments represent both clastic and carbonate depositional systems across continental, transitional, and marine settings.

1. Depositional Environments

2. Aeolian
• Facies/Depositional Areas:
– Dune sandstones (fine-med sandstones, large scale cross-bedding, hierarchy of erosional
surfaces, no mud, clay or mica, well sorted, grainflow/grainfall laminae)
– Interdunes (fine-med sandstones, lag deposits, bioturbation, adhesion ripples, water
deposits, poorly sorted)
– Evaporites – playa lakes (salts)
– Sabkha - intense early diagenesis, dolomites, tee-pee structures, salts.
– Fluvial – ephemeral rivers, caliche (calcite cements), gravelly.
– Alluvial fans – gravelly.
• Geometries:
– Dune/Interdunes = sheetlike
– Evaporites = sheets to lenses
– Sabkha – ribbons to sheets
– Fluvial – ribbons to pods
– Alluvial fans – wedges or fans.
• Trends:
– No trends
• Reservoir/Seal facies:
– Reservoirs - Dune sands, maybe fluvial or alluvial.
– Seals – evaporites, sabkha facies
– Baffles – interdunes
• Associations:
– Red bed associations – other non-marine reddish coloured environments.

3. Fluvial
• Facies/Depositional Areas:
– Channels (erosional bases, complex internal structures, cross-bedding, cross-
lamination, bar-foresets, erosional surfaces, mud layers)
– Amalgamated channels (multiple channels staked vertically or
horizontally, called braid belts in braided fluvial systems)
– Pointbars (meandering systems only – inclined accretion surfaces)
– Floodplains (mud, mud, mud, coal, mud, silts (lake or flood), thin
sands, crevase splays, levees, bioturbation)
• Geometries:
– Channels – ribbons
– Channel belts – lenses, ribbons
– Pointbars – pods or lenses
– Floodplains - sheetlike
• Trends:
– Fining upwards in channels and pointbars
• Reservoir/Seal facies:
– Reservoirs – channels, pointbars, crevase splays, levees, floodplain sands....
– Braided systems tend to be higher NTG
– Seals – floodplain muds, lake deposits (muds)...

4. Shallow marine/Shoreline
• Facies/Depositional Areas:
– Offshore – below Storm Wave Base and also between SWB and
FairWeather Wave Base, mud, mud, thin sands (turbidites), bioturbation
(lots)...
– Shoreface – above FWWB, sands (thin muds), hummocky cross-
stratification, bioturbation
– Foreshore – exposed at low tide, minimal bioturbation, gently inclined
cross-stratification or lamination, cross-bedding.
– Backshore – above high tide, dunes, lagoons (mud), evaporites (salts)...
• Geometries:
– Sheetlike (linear depositional area, which migrates through time with
shoreline location).
• Trends:
– Coarsening-upwards... Normally progradation is taking place. However
sometimes if sea-level rises transgression therefore fining upwards.
• Reservoir/Seal facies:
– Reservoirs – Shoreface, Foreshore and Backshore dunes
– Seals - Offshore muds and backshore lagoon/evaporites

5. Deltaic
• Facies/Depositional Areas:
– Mouthbars – fluvial dominated delta (silt to sand, cross-bedding)
– Shorelines – wave dominated delta (see previous slide)
– Channel/ridge systems – tide dominated delta (fining-up sands to silts to
muds)
– Fluvial – delta top (see previous slide), except that coal beds tend to correlate
in delta top settings, due to very flat delta top morphology.
– Marine (offshore) – delta front (see previous slide)
• Geometries:
– Mouthbars – lenses
– Shorelines – sheetlike
– Channels – ribbons
– Marine - sheetlike
• Trends:
– Coarsening-up overall, mouthbars coarsen-up, channels fining-up.
• Reservoir/Seal facies:
– Reservoir : Mouthbars, shoreline, channel, other fluvial....
– Seals : Marine muds, fluvial muds...

6. Deep Marine
• Facies/Depositional Areas:
– Turbidites (sequence of sedimentary structures
(massive, laminated, cross-laminated or convolute laminated, laminated
grading up to bioturbated mud), sharp or erosive based, fining
upwards, grain alignment)
– Gravity flow deposits – debris flows... Very poorly sorted, mud matrix
– Marine mud (pelagic).
– Oozes – biogenic muds, siliceous or carbonate, chert or limestone.
• Geometries:
– Sheets (turbidites, marine mud, oozes)
– Fans (submarine fans), channel ribbons (channelized turbidites)
• Trends:
– Fining upwards in turbidites...
• Reservoir/Seal facies:
– Reservoir : Turbidites
– Seal : Mud, oozes, debris flows.

7. Carbonates
• Facies/Depositional Areas:
– Reef (corals, framework carbonates, breccia of framework
carbonate grains)
– Ramp (shoals, bars, mounds)
– Carbonate mud fields
• Geometries:
– Reef – lenses, wedges
– Ramps – sheets, lenses, pods
– Carbonate mud - sheet
• Trends:
– Not much – coarsening-upwards in shoal and mound systems.
• Reservoir/Seal facies:
– Reservoirs: frameworks carbonates, packstones...
– Seals: carbonate muds
– Secondary diagenesis... Fractured reservoirs and dissolution....