1. Contents Introduction Sedimentology – concepts Fluvial environments
Deltaic environments
Coastal environments
Offshore marine environments
Sea-level change
Sequence stratigraphy – concepts
Marine sequence stratigraphy
Nonmarine sequence stratigraphy
Basin and reservoir modeling
Reflection
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2. Sedimentary Rocks and Stratigraphy:
The three most abundant kinds of sediment:
Quartz Sand,
Shale,
Limestone

3. Simple Ideal Model for the Evolution of Sedimentary Rocks:
High ENERGY Low
“Rocks reflect the conditions at which they formed.” --Fichter & Poche

4. Offshore marine environments
Shallow marine environments :
pericontinental seas that occur along continental margins and have a shoreline-shelf-slope profile; and
epicontinental seas that cover continental interiors and exhibit a ramp morphology
Under idealized conditions the offshore-transition and offshore exhibit a systematic decrease in (wave) energy and grain size; however, such an ‘equilibrium shelf’ is commonly not encountered
Tides and ocean currents can strongly complicate shelf hydrodynamics
Rapid sea-level changes (e.g., during the Quaternary) result in relict shelf sediments that are genetically unrelated to the present conditions
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6. Offshore marine environments
IDEAL: offshore-transition and offshore
decrease in (wave) energy and grain size;
however, such an ‘equilibrium shelf’ not common!
Tides and ocean currents can complicate shelf hydrodynamics
Rapid sea-level changes (e.g., during the Quaternary) leave relict shelf sediments that are genetically unrelated to the present conditions
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11. Offshore marine environments
Wave/storm-dominated shelves, ideal:
lower shoreface: sands
below fairweather wave base: alternating sands and muds,
below storm wave base: muddy facies
Storms leave a strong imprint (i.e., storm deposits have a high preservation potential), since they wipe out fairweather deposits
Tempestites form during storm events and exhibit a characteristic facies succession from an erosional basal surface with sole marks, to a sandy unit with hummocky cross stratification overlain by wave-rippled sand, finally giving way to muds
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12. FUS
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13. Offshore marine environments
Tempestites form during storm events
Their facies succession:
erosional basal surface with sole marks,
sandy unit with hummocky cross stratification topped by wave-rippled sand,
muds
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18. Blank Slide
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19. Offshore marine environments
Tides lead to circulation around amphidromic points, ranging from circular to almost rectilinear depending on the shape of the water body
Tide-dominated shelves exhibit a distinct suite of bedforms in relation to current velocity and sediment (sand) supply
Erosional features, sand ribbons, and sand waves go along with decreasing flow velocities, commonly associated with mud-draped subaqueous dunes; tidal sand ridges (tens of m high, many km across) are characteristic of shelves with a high supply of sand
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22. Offshore marine environments
Tides lead to circulation around amphidromic points, ranging from circular to almost rectilinear depending on the shape of the water body
Tide-dominated shelves, bedforms:
Erosional features,
sand ribbons, and
sand waves go along with decreasing flow velocities, commonly associated with mud-draped subaqueous dunes;
tidal sand ridges (tens of m high, many km across) are characteristic of shelves with a high supply of sand
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23. Offshore marine environments
Ocean current-dominated shelves are relatively rare; geostrophic ocean currents can lead to the formation of bedforms that are somewhat comparable to those of tide-dominated shelves
Mud-dominated shelves
usually associated with large, tropical rivers with a high suspended load (e.g., Amazon and Yellow Rivers) that can be transported along the shelf if currents are favorable
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24. Offshore marine environments
Deep marine environments include the continental slope and the deep sea
Subaqueous mass movements (mostly sediment gravity flows) involve a range of transport mechanisms, including plastic flows and fluidal flows
Debris flows are commonly laminar and typically do not produce sedimentary structures
Turbidity currents are primarily turbulent and more diluted; they commonly evolve from debris flows
Debris-flow deposits are poorly sorted, related to the ‘freezing’ that occurs once shear stresses can not overcome the internal shear strength
A key mechanism in turbidity currents is ‘autosuspension’ (turbulence --> suspended load --> excess density --> flow --> turbulence)
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26. Animation
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27. Offshore marine environments
Deep marine environments include the continental slope and the deep sea
Subaqueous mass movements (mostly sediment gravity flows) involve a range of transport mechanisms, including plastic flows and fluidal flows
Debris flows are commonly laminar and typically do not produce sedimentary structures
Turbidity currents are primarily turbulent and more diluted; they commonly evolve from debris flows
Debris-flow deposits are poorly sorted, related to the ‘freezing’ that occurs once shear stresses can not overcome the internal shear strength
A key mechanism in turbidity currents is ‘autosuspension’ (turbulence --> suspended load --> excess density --> flow --> turbulence)
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28. Offshore marine environments
Deep marine environments include the continental slope and the deep sea
Subaqueous mass movements (mostly sediment gravity flows) involve a range of transport mechanisms, including plastic flows and fluidal flows
Debris flows are commonly laminar and typically do not produce sedimentary structures
Turbidity currents are primarily turbulent and more diluted; they commonly evolve from debris flows
Debris-flow deposits are poorly sorted, related to the ‘freezing’ that occurs once shear stresses can not overcome the internal shear strength
A key mechanism in turbidity currents is ‘autosuspension’ (turbulence --> suspended load --> excess density --> flow --> turbulence)
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29. Animation 1
Animation 2
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31. Offshore marine environments
Contrary to debris flows, turbidites exhibit a distinct proximal to distal fining
The idealized Bouma sequence, is most useful for medium-grained, sand-mud turbidites, but it must be applied with care
divisions A-E (bottom to top):
A: Rapidly deposited, massive sand
B: Planar stratified (upper-stage plane bed) sand
C: Small-scale (climbing ripple) cross-stratified fine sand
D: Laminated silt
E: Homogeneous mud
High-density and low-density turbidity currents give rise to incomplete, coarse-grained (A) and fine-grained (D-E) turbidites respectively
Contourites are formed by ocean currents and commonly represent reworked turbidites
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35. Offshore marine environments
Contrary to debris flows, turbidites exhibit a distinct proximal to distal fining
The idealized Bouma sequence, consisting of divisions A-E, is most useful for medium-grained, sand-mud turbidites, but it must be applied with care
A: Rapidly deposited, massive sand
B: Planar stratified (upper-stage plane bed) sand
C: Small-scale (climbing ripple) cross-stratified fine sand
D: Laminated silt
E: Homogeneous mud
High-density and low-density turbidity currents give rise to incomplete, coarse-grained (A) and fine-grained (D-E) turbidites respectively
Contourites are formed by ocean currents and commonly represent reworked turbidites
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36. Offshore marine environments
Submarine canyons at the shelf edge (commonly near river deltas) are connected to submarine fans on the ocean floor
Size of submarine fans is inversely related to dominant grain size
mud-dominated submarine fans are 104–106 km2,
sand or gravel-dominated submarine fans are 101–102 km2
Submarine fans share several characteristics with deltas; they consist of a feeder channel that divides into numerous distributary channels bordered by natural levees (‘channel-levee systems’) and are subject to avulsions
Proximal fan (trunk channel)
Medial fan (lobes)
Distal fan
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38. Animation
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40. Offshore marine environments
Submarine canyons at the shelf edge (commonly related to deltas) are connected to submarine fans on the ocean floor
The size of submarine fans is inversely related to dominant grain size (i.e., mud-dominated submarine fans are 104–106 km2, sand or gravel-dominated submarine fans are 101–102 km2)
Submarine fans share several characteristics with deltas:
feeder channel that divides into numerous distributary channels bordered by natural levees (‘channel-levee systems’) and are subject to avulsions
Proximal fan (trunk channel)
Medial fan (lobes)
Distal fan
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44. Offshore marine environments
Hemipelagic sediments:
at least 25% of fine-grained (muddy) terrigenous material
deposited from suspension, commonly after transport by hemipelagic advection
Distal, muddy turbidites merge gradationally into hemipelagic deposits
Eolian dust is an important component (~50%) of hemipelagic (and pelagic) facies
Black shales have a 1–15% organic-matter content and form in anoxic bottom waters, sometimes in shallow seas (e.g., Western Interior Seaway)
Pelagic sediments are widespread in the open ocean and primarily have a biogenic origin
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