Page 139 - Open-Hole Log Analysis and Formation Evaluation
P. 139
Formation
10
Factor
A
Il.
1
the
the
they
6.18).
where
FIGURE
do
produce
only
7
mations;
constant.
proper
6.17
Because
is
and thus. at
not
PRACTICAL
:
METHODS
but
the
some
observation
in
work
Archie’s
Variations
as
marriage
that
conductive
shal
See
:
well.
saturation
when
model
-
spectacular
a
Tom
Generalized F-to-¢
PETROPHYSICS
10
path, his
Porosity
between
¢
formations
ons
%
of porosity ate
results.
exponent
T
Decreasing
considers
a
formation
and
One
is
the
Relationship.
normal
is
OF ANALYSIS AND APPLICATION
irreducible water saturation, the
petrophysics
relationships
of
and where
OF
(Clastics)
the
above
and
work
usually
the
product
electrolyte
on a local
most
log
set
well
RESULTS
in
100
of ¢
to
in
scale,
the
2
connate water
and
is
transition
analysis
P
clean
S,,
(see
“So
owing
interesting
pores
= 4
fig.
for-
zone,
Intercept
can
to
isa
is
as
fresh,
0.0001
'
6.
Cor
the
this
tion
plot
line.
line.
there
water
water
figure
@
FIGURE
THE
This
of
smaller,
changes
60%,
are
analyzed
reduced,
laid down
saturation
zone.
6.18
in
a
6.19,
formations.
production
overlooked
or
surprisingly
maintaining
on
qT
Reservoirs
thus
X S,,
(Ru bo/ Row)
permeability,
. 1 - Liitit 100 % Sw wet) 10 — n = (oil t mee i Increasing m (Hard Rock) 1000 100 = 124 OF ROCK/FLUID SYSTEMS 125
S,,
Points.in
fall
a
0.001
by
PHYSICS
n
characteristics.
knowledge
the
can
p,
as
@ versus
simply
Note
for
¢’and
high
production
on
the
production.
may
Figure
greater
is
observation
even
is
For
be
can
that
the
be
product
to
fewer
whatever)
has
6.19
water
in
S,,are
depositional
be
S,,-will
decreasing
a
at
constant
larger
be
a
when
foot-by-foot
on
a Function
¢
pore
transition
points
there
log-log paper, where points at
used
and
Conversely,
proportion
reveal
a.hyperbola.
those who were
To
they
expected.
basis
particular
(clastics)
0.01
as
are
not
in
X S,,
Ro/R:
zone
practical
illustrates
a
the
saturations
expected
for
characterized
throats.
more
at
once
no
have
This
of the
irreducible
Figure
the
plot
low-porosity,
fluids
can
linear scales
environment at
by
Of Ro/R, and
basis
to
irreducible
n.
product.
pore
be
water
more
6.20
the
taught
and
the
for
the
presence
porosity
salient
application.
can
depending
@
(1)
and owing to subsequent diagenesis.
moderate
Either way,
or
present.
saturation
irreducible
and
formations with
If,
I
right
X
throats
on
fact
0.1
shows
be
the
After
troubles
time the
a
tolerated
°
a
is
for
phenomenon.
S,,;
the
are
if S,,is
the points
values
good
water
a
held
Figure
predicting
and
of the
absence
at
all
mean
of
less
in
zone
Note
of
similar
small
(2)
a
6.21
without
saturation,
S,,,
too
the
has
product,
than
do
radius
plot
number
fear
ones
saturation,
often
transi-
low-permeability formation,
not
porosity and
and
production
been
shows
saturation plot ona straight
some
or
irreducible
water
pore
on
mobility ratio
ris
that,.on
irreducible
a
50%
locally, porosity is
sediments were
of
of
1
4