“storm deposits - sea level indicators” christopher g. st. c. kendall carbonate storm deposits...
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“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
Carbonate Storm DepositsCarbonate Storm DepositsIndicators of Sea Level Indicators of Sea Level
Position?Position?Professor Christopher G. St. C. KendallProfessor Christopher G. St. C. Kendall
University of South CarolinaUniversity of South [email protected] [email protected] 803 – 777 2410803 – 777 2410
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
Carbonates Storm Carbonates Storm DepositsDeposits
Carbonates Storm Carbonates Storm DepositsDeposits
Represented by cycles of carbonate Represented by cycles of carbonate that are coarse at base & fine up to that are coarse at base & fine up to shale shale
Coarser portion of each cycle is Coarser portion of each cycle is interpreted to be result of water being interpreted to be result of water being shallow enough for storms to sort sea shallow enough for storms to sort sea floor, while fines represent water deep floor, while fines represent water deep enough to afford protection from enough to afford protection from effects of similar stormseffects of similar storms
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
Setting of Storm DepositsSetting of Storm DepositsSetting of Storm DepositsSetting of Storm Deposits
Presence of storm deposits are Presence of storm deposits are indices of lack of cementation indices of lack of cementation and/or organic binding and/or organic binding
Occurrence of larger metazoan Occurrence of larger metazoan skeletons enhances capacity for skeletons enhances capacity for surface of ramp to build above a surface of ramp to build above a shelf equilibrium profileshelf equilibrium profile
Carbonate storm deposits Carbonate storm deposits associated with ramp margins that associated with ramp margins that lack organic binding or lack organic binding or cementation enabling sediment cementation enabling sediment dispersal:dispersal:
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
Bioclastic packstones , & calcareous shales - Kope FmBioclastic packstones , & calcareous shales - Kope Fm
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
Bioclastic packstones , & hummocky bedded calcareous silts - Fairview Fm
Bioclastic packstones , & hummocky bedded calcareous silts - Fairview Fm
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
Bioclastic packstones , & hummocky bedded calcareous silts - Fairview Fm
Bioclastic packstones , & hummocky bedded calcareous silts - Fairview Fm
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
High-stand Surface of High-stand Surface of CondensationCondensation
Mid Slope - Storm DepositsMid Slope - Storm DepositsMid Slope - Storm DepositsMid Slope - Storm Deposits
Note lack of Note lack of Tidal Flat fillTidal Flat fill
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
High-stand Surface of High-stand Surface of CondensationCondensation
Lower Slope - Storm Lower Slope - Storm DepositsDeposits
Lower Slope - Storm Lower Slope - Storm DepositsDeposits
Note lack of Note lack of Tidal Flat fillTidal Flat fill
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
High-stand Surface of High-stand Surface of CondensationCondensation
Upper Slope - Storm Upper Slope - Storm DepositsDeposits
Upper Slope - Storm Upper Slope - Storm DepositsDeposits
Note lack of Note lack of Tidal Flat fillTidal Flat fill
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
Maximum Flooding SurfaceMaximum Flooding Surface
Crest of Margin - Storm Crest of Margin - Storm DepositsDepositsCrest of Margin - Storm Crest of Margin - Storm DepositsDeposits
Note Tidal FlatNote Tidal Flat& Standard& StandardSequenceSequence
StratigraphicStratigraphicSurfacesSurfaces
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
Examples of Storm Examples of Storm DepositsDeposits
Examples of Storm Examples of Storm DepositsDeposits
Upper Jurassic Hanifa & Jubaila Fms Upper Jurassic Hanifa & Jubaila Fms of Arabian cratonic margin basinof Arabian cratonic margin basin
Lower Cretaceous of Arabian GulfLower Cretaceous of Arabian Gulf Oligocene/Miocene of the Murray Oligocene/Miocene of the Murray
Basin Basin Upper Ordovician of Kentucky & Upper Ordovician of Kentucky &
Ohio. Ohio.
Carbonate storm deposits Carbonate storm deposits associated with ramp margins associated with ramp margins include:include:
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
Drafted by Waite 99, after James 1984)
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
Paradoxes of Storm Paradoxes of Storm Deposits? Deposits? Paradoxes of Storm Paradoxes of Storm Deposits? Deposits?
Wide spread storm events have been identified on ramps Wide spread storm events have been identified on ramps explaining occurrence of shallow water cycles that do not explaining occurrence of shallow water cycles that do not make it to sea level make it to sea level
Surface of ramps on which storm deposits occur related to:Surface of ramps on which storm deposits occur related to:An ecological base level that does not match hydrodynamic base An ecological base level that does not match hydrodynamic base level but is connected to it ( Pomar(2001)level but is connected to it ( Pomar(2001)Lack of local cementation Lack of local cementation
Ramp response to increase of accommodation is ascribed to Ramp response to increase of accommodation is ascribed to EustasyEustasyTectonic eventsTectonic events
Storm deposits can be sorted, rounded, & incorporate Storm deposits can be sorted, rounded, & incorporate several generations of sediment component that are product several generations of sediment component that are product of of
Single large storms at sea level low?Single large storms at sea level low?Multiple storms?Multiple storms?Cannibalism supports lack of cementation & binding on ramp? Cannibalism supports lack of cementation & binding on ramp?
Micritization of the surfaces of gravels grains can be Micritization of the surfaces of gravels grains can be common but more often it is not:common but more often it is not:
Time spent exposed on sea floor insufficient for cyanobacteria Time spent exposed on sea floor insufficient for cyanobacteria colonization? colonization?
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
ConclusionsConclusionsConclusionsConclusions Wide spread sea level events matched to Wide spread sea level events matched to
storm prone portions of geological sectionstorm prone portions of geological section Accommodation controls carbonate Accommodation controls carbonate
productivityproductivityLows favor carbonate production and storm Lows favor carbonate production and storm sortingsorting
Highs reduce carbonate productivity and induce Highs reduce carbonate productivity and induce condensation of sectioncondensation of section
This response explains the lack of tidal flat fill on This response explains the lack of tidal flat fill on rampsramps
“Storm Deposits - Sea Level Indicators”Christopher G. St. C. Kendall
Lecture Ends!!Lecture Ends!!Lecture Ends!!Lecture Ends!!
And so for a And so for a drink!!!drink!!!