Miocene
The
Miocene
Epoch
is
a
period
of
time
that
extends
from
about
5
million
to
24
million
years
before
the
present.
As
with
other
older
geologic
periods,
the
rock
beds
that
define
the
start
and
end
are
well
identified,
but
the
exact
dates
of
the
start
and
end
of
the
period
are
slightly
uncertain.
The
Miocene
was
named
by
Sir
Charles
Lyell.
The
name
means
roughly
"less
recent"
and
refers
to
the
essentially
modern
mammalian
faunas.
The
Miocene
follows
the
Oligocene
Epoch
and
is
followed
by
the
Pliocene
Epoch.
The
Miocene
is
the
fourth
epoch
of
the
Tertiary
Era.
The
Miocene
boundaries
is
not
set
at
an
easily
identified
worldwide
event
but
rather
at
regional
boundaries
between
the
warmer
Oligocene
the
relatively
cooler
Miocene
and
the
even
cooler
Pliocene.
The
Miocene
faunal
stages
from
youngest
to
oldest
are:
-
Aquitanian
-
Burdigalian
-
Langhian
-
Serravallian
-
Tortonian
-
Messinian
Continents
continued
to
drift
toward
their
present
positions.
Of
the
modern
geologic
features,
only
the
land
bridge
between
South
America
and
North
America
was
absent.
Climates
remained
moderately
warm
although
slow
global
cooling
that
eventual
led
to
the
Pleistocene
glaciations
continued.
Mountain
building
took
place
in
Western
North
America
and
Europe.
Both
continental
and
marine
Miocene
deposits
are
common
worldwide
with
marine
outcrops
common
near
modern
shorelines.
Well
studied
continental
exposures
occur
in
the
American
Great
Plains
and
in
Argentina.
Both
marine
and
continental
fauna
were
fairly
modern.
Recognizable
wolves,
horses,
beaver,
deer,
camels,
crows,
ducks,
owls,
whales,
etc
existed
in
the
Miocene.
Only
in
isolated
South
America
and
Australia
did
widely
divergent
fauna
exist.
- See
also:
Geologic
Time
Scale
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