GE0-3112 Sedimentary processes and products
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GE0-3112 GE0-3112 Sedimentary processes and products Sedimentary processes and products Lecture 1. Depositional controls Lecture 1. Depositional controls Geoff Corner Geoff Corner Department of Geology Department of Geology University of Tromsø University of Tromsø 2006 2006 Literature: Literature: - Reading, 1996, Ch.2. Controls on the sedimentary rock - Reading, 1996, Ch.2. Controls on the sedimentary rock record. record. - Leeder, 1999, ch. 1, 2, 13, 14, 15, 27, 28 - Leeder, 1999, ch. 1, 2, 13, 14, 15, 27, 28
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Lecture 1. Depositional controls. GE0-3112 Sedimentary processes and products. Geoff Corner Department of Geology University of Tromsø 2006. Literature: - Reading, 1996, Ch.2. Controls on the sedimentary rock record. - Leeder, 1999, ch. 1, 2, 13, 14, 15, 27, 28. Depositional controls. - PowerPoint PPT Presentation
Transcript of GE0-3112 Sedimentary processes and products
GE0-3112GE0-3112 Sedimentary processes and products Sedimentary processes and products
Lecture 1. Depositional controlsLecture 1. Depositional controls
Geoff CornerGeoff CornerDepartment of GeologyDepartment of GeologyUniversity of TromsøUniversity of Tromsø20062006
Literature:Literature:- Reading, 1996, Ch.2. Controls on the - Reading, 1996, Ch.2. Controls on the
sedimentary rock record.sedimentary rock record.- Leeder, 1999, ch. 1, 2, 13, 14, 15, 27, 28- Leeder, 1999, ch. 1, 2, 13, 14, 15, 27, 28
Depositional controlsDepositional controls►Sediment supplySediment supply►Accomodation spaceAccomodation space
Corner, in press
Sediment supplySediment supply
A) Terrigenous systemsA) Terrigenous systems
(allogenic, extrabasinal sediment (allogenic, extrabasinal sediment source) –clastic sediments transported source) –clastic sediments transported into the basin.into the basin.
B) Biochemical/chemical systemsB) Biochemical/chemical systems
(autogenic, intrabasinal sediment (autogenic, intrabasinal sediment source) – carbonate and other source) – carbonate and other sediments produced in the basin.sediments produced in the basin.
Sediment supplySediment supply► Variations in:Variations in:
Volume and rate of deliveryVolume and rate of delivery Grain size (calibre), etc.Grain size (calibre), etc. Petrographic composition (siliciclastic, carbonate)Petrographic composition (siliciclastic, carbonate) Mechanism of delivery (process)Mechanism of delivery (process)
► Determined by:Determined by: Bedrock geologyBedrock geology Tectonics/reliefTectonics/relief ClimateClimate Basinal water chemistry (for carbinates, etc.)Basinal water chemistry (for carbinates, etc.)
► (Denudation processes (weathering and erosion) and their (Denudation processes (weathering and erosion) and their intensity– dependent upon:intensity– dependent upon: reliefrelief Climate)Climate)
Sediment source (clastics)Sediment source (clastics)
►WeatheringWeathering
Sediment source (clastics)Sediment source (clastics)
►WeatheringWeathering►Mass-wastingMass-wasting
Sediment source (clastics)Sediment source (clastics)
►WeatheringWeathering►Mass-wastingMass-wasting►ErosionErosion
Sediment source (clastics)Sediment source (clastics)
►WeatheringWeathering►Mass-wastingMass-wasting►ErosionErosion►AttritionAttrition
Source areaSource area
►ReliefRelief High reliefHigh relief Low reliefLow relief
Source areaSource area
►ReliefRelief►BedrockBedrock
Hard crystallineHard crystalline Soft sedimentarySoft sedimentary
Sediment delivery systemSediment delivery system
►GlaciersGlaciers►Mass-movementMass-movement►RiversRivers►WindWind►WavesWaves►Tidal and ocean currentsTidal and ocean currents
Accomodation spaceAccomodation space
►Basin morphologyBasin morphology►Base-levelBase-level
Corner, in press
Basin morphologyBasin morphology
► Fjord exampleFjord example
Corner, in press
Basin morphologyBasin morphology
► Tectonic basin Tectonic basin exampleexample
Basin morphologyBasin morphology
► Shelf exampleShelf example
Base levelBase level
►ConceptConcept►Sea-levelSea-level
Sea levelSea level
► Eustatic (global) sea Eustatic (global) sea level (eustasy)level (eustasy)
► Uplift/subsidence Uplift/subsidence (isostasy)(isostasy)
► Relative sea-levelRelative sea-level► Water depth Water depth
Coe & Church, in Coe (ed.) 2003
Transgression and regressionTransgression and regression
Galloway & Hobday 1996
Controls on deposition IIControls on deposition II
► Independent variablesIndependent variables►Extrinsic and intrinsic factorsExtrinsic and intrinsic factors
Controls on deposition IIControls on deposition II
► Independent Independent variables:variables: ClimateClimate TectonicsTectonics
Church & Coe, in Coe (ed.) 2003
ClimateClimate
MilankovitchMilankovitch
Controls on deposition IIControls on deposition II
► Independent variablesIndependent variables►Extrinsic and intrinsic factorsExtrinsic and intrinsic factors
Depositional geometryDepositional geometry
► ProgradationProgradation
► RetrogradationRetrogradation
► AggradationAggradation
Prothero & Schwab 1996
Facies models and depositonal Facies models and depositonal systemssystems
► FaciesFacies► Facies succession (vertical Facies succession (vertical
succession; fining-upward, succession; fining-upward, thickening-upward trends, thickening-upward trends, etc.)etc.)
► Architectural element - Architectural element - medium-scale three-medium-scale three-dimensional depositional dimensional depositional body characterised by a body characterised by a distinctive assemblage of distinctive assemblage of facies and geometry. facies and geometry.
► Depositional system - three-Depositional system - three-dimensional assemblage of dimensional assemblage of lithofacies genetically linked lithofacies genetically linked by active or inferred by active or inferred processes and environments.processes and environments.
Hierarchy of depositional Hierarchy of depositional elementselements
StrataStrata Depositional unitDepositional unit Example ExampleAssemblagesAssemblages
LaminaLamina BedformBedform Ripple Ripple Facies Facies
BedBed Bed/arch. elementBed/arch. element Bar Bar Facies ass./ Facies ass./
MemberMember Architectural elementArchitectural element Channel Channel arch.elementarch.element
FormationFormation Depositional basinDepositional basin Valley-fill Valley-fill Facies Facies assoc.assoc.
GroupGroup Basin/settingBasin/setting Foreland Foreland
Miall, in Walker & James (eds.) 1992
Hierarchy of depositional Hierarchy of depositional elementselements
Miall, in Walker & James (eds.) 1992
Facies analysisFacies analysis
► Key to Key to analysinganalysing deposits: meaningful deposits: meaningful identification of bounding surfaces, facies identification of bounding surfaces, facies associations and/or architectural elements.associations and/or architectural elements.
► Key to Key to understandingunderstanding deposits: deposits: interpretation of depositional elements with interpretation of depositional elements with reference to depositional modelsreference to depositional models
Depositional model =Depositional model =
process + bedforms/geometry + preserved process + bedforms/geometry + preserved depositsdeposits
FaciesFacies
Einsele 1992
Facies and facies codesFacies and facies codes
► FaciesFacies
Miall, in Walker & James (eds.) 1992
Facies successionsFacies successions
Miall, in Walker & James (eds.) 1992
Architectural elementsArchitectural elements
Miall, in Walker & James (eds.) 1992
Sequence stratigraphySequence stratigraphy
Reading 1996
Practical tips on Practical tips on sedimentological analysissedimentological analysis
►1. Think process1. Think process►2. Think three-dimensional2. Think three-dimensional►3. Think ’big picture’3. Think ’big picture’
Tip 1. Think ’process’Tip 1. Think ’process’
►Example 1 –climbing-ripple beddingExample 1 –climbing-ripple bedding
Tip 1. Think ’process’Tip 1. Think ’process’
►Example 2 Example 2
– – Fjord-valley fill Fjord-valley fill stratigraphystratigraphy
Glaciomarine deposition
A
Outlet glacier
Fjord glacier
Meltwater
B
Valley glacier
Meltwater
Glaciofluvialdelta
Valley glacier
CMeltwater
Marine deposition
Fluvialdelta
RiverD
Fluvial terracing
ERiver
Post
gla
cial
Degla
cial
Corner, in press
Deglacial-postglacial surface
I
IIIc
IVd
IIa
Df
Dv
PMaximum flooding surface
Regressive accretionary surface
Marine limit
I
I
IIIb
IIb
IIdIIc
IVc
Glacial trough
Cross section X - X’
X’X
A
BMarine limit
IVb
1
3 2
IIb
IIc
IIa
I
IVd
IId
Df
Dv
PIIIc
IVc
II
IIIIV
I
DTST (Df)
PRST (P)
DHST (Dv)
Time
Sea
leve
l
Regressive accretionary surface
PDvDf
Postglacial forced regressive (PRST)
Depositional episodes/sequence tracts
Deglacial (fjord glacier) transgressive (DTST)
Deglacial (valley glacier) highstand (DHST)
Bounding surfaces
Fluvial erosion surface
Deltaic erosion surface
Fluvial accretion surface
IV
III
Depositional elements
II
I
Fjord floor
Delta foreset
- Fluvial (P)IVd
Ice-contact (Df)
Glaciofluvial delta foreset (Df/Dv)
- Marine (P)IIc - Prodelta (P)IId
- Glaciomarine (Df/Dv)IIa/IIb
- Delta topset (P)IVc
IIIc - Delta foreset (P)
Terrace top
- Glaciofluvial delta topset (Df/Dv)IVa/IVb
IIIa/IIIb-
Transgressive systems tractTransgressive systems tract
Highstand systems tractHighstand systems tract
Forced-regressive systems tractForced-regressive systems tract
Corner, in press
Tip 2. Think ’3D’Tip 2. Think ’3D’
►Example 1 – Trace fossils in sectionExample 1 – Trace fossils in section
Tip 2. Think 3DTip 2. Think 3D
►Example 2 – primary sedimentary Example 2 – primary sedimentary structuresstructures
Tip 2. Think 3DTip 2. Think 3D
► Example 3 – Vertical Example 3 – Vertical (2D) sections(2D) sections
Vorren & Mangerud, in press
Tip 3. Think ’big picture’Tip 3. Think ’big picture’
►Spatial aspects of the systemSpatial aspects of the system►Time aspects and system controlsTime aspects and system controls
Glaciomarine deposition
A
Outlet glacier
Fjord glacier
Meltwater
B
Valley glacier
Meltwater
Glaciofluvialdelta
Valley glacier
CMeltwater
Marine deposition
Fluvialdelta
RiverD
Fluvial terracing
ERiver
Post
gla
cial
Degla
cial
