Controls on Facies Architecture and Preservation

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Controls on Facies Architecture and
Preservation the three dimensional geometry of
deposits is controlled by rates of sediment
supply (and sediment type) climate tectonics
accommodation space changes in eustatic sea
level rates of subsidence These factors are
inter-related!
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http//www.uga.edu/strata/sequence/accommodation.
html
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Variations in deposits with same sea level history
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Climate variation in the Gulf of Mexico drainage
systems
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Sea-Level Controls
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Rates of Change these different controls
change at different rates--helps define which
control at work for a given depositional
result 102-103 years (especially short during
glacial episodes) climate, sea-level change,
or fluvial avulsion 106 years tectonics,
subsidence
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Accommodation Space the balance between
subsidence, eustasy, and sediment supply will
control the extent and thickness of
deposits subsidence in large part a function of
the type if basin tectonic basins (fore-arc,
back-arc, foreland, rift basins) have
relatively rapid, potentially episodic
subsidence cratonic and passive margin
basins have slow and continuous subsidence
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eustasy changes in the volume of ocean
basins mainly by changes in rates of sea floor
spreading also by the volume of sediment in
the basins 102 k.y. - 105 k.y. changes in
the volume of water within those basins
glacial history--by far the dominant
control ocean temperature volume of ground
water 1 - 100 k.y. (with amplitudes gt100m)
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Comparison of Stage 5 deposits
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The present is the key to some of the past...
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References throughout for Class 3 332 notes
from Anderson