What do we use the fossil record for?

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What do we use the fossil record for?
3. Interpreting past environments
At any one time different sediments types are
being deposited in different places. No one
environment stretches indefinitely far in any
direction.
http//www.geology.ohio-state.edu/vonfrese/gs100/
lect29/xfig29_02.jpg
http//oceanworld.tamu.edu/students/coral/images/c
oral_reef_1.jpg
http//www.wsgs.uwyo.edu/Coal/coal_brochure/images
/fig1_swamp.jpg
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http//strata.geol.sc.edu/Bahamas/images/040-Heira
rchy-of-Facies.jpg
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http//csmres.jmu.edu/geollab/fichter/SedRx/carbde
poenvir.html
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http//csmres.jmu.edu/geollab/fichter/SedRx/meande
rriver.html
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Facies all of the characteristics of a
particular rock unit. The characteristics of
the rock unit come from the depositional
environment. Every depositional environment
puts its own distinctive imprint on the sediment,
making a particular facies. Thus, a facies is a
distinct kind of rock for that area or
environment.
http//gpc.edu/pgore/geology/geo102/facies.htm
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A Sandstone facies (beach environment)B
Shale facies (offshore marine environment)C
Limestone facies (far from sources of terrigenous
input)
Each depositional environment grades laterally
into other environments.
http//gpc.edu/pgore/geology/geo102/facies.htm
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http//www3.interscience.wiley.com8100/legacy/col
lege/levin/0470000201/chap_tutorial/ch12/images/le
03_42.jpg
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Onlap (Transgressive) Sequences
Shifting Facies through Time
Time Rock Unit
Time Rock Unit
Time Rock Unit
Time Transgressive Unit
Time Rock Unit
Time Rock Unit
Time Rock Unit
Beach sandstone
Near Shelf shale
Far Shelf limestone
Beach moves farther away
Water gets deeper
Sediment becomes finer
FUS Fining Upward Sequence Transgressive
Sequence
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Offlap (Regressive) Sequences
Shifting Facies through Time
Time Transgressive Rock Unit
Beach sandstone
Time Rock Unit
Time Rock Unit
Time Rock Unit
Near Shelf shale
Time Rock Unit
Time Rock Unit
Far Shelf limestone
Beach moves closer
Water gets shallower
Sediment gets coarser
CUS Coarsening Upward Sequence Regressive
Sequence
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Transgressive Sequence
Regressive Sequence
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Walther's Law sedimentary environments that
started out side-by-side will end up overlapping
one another over time due to transgressions and
regressions. The result is a vertical sequence
of beds. The vertical sequence of facies
Represents former adjacent depositional
environments.
Which sequence of rock layers represents a
transgression?
http//gpc.edu/pgore/geology/geo102/facies.htm