Page 32 - Open-Hole Log Analysis and Formation Evaluation

7
@
2
In
the
and
a
There
helps
index
These
There
pulsed
the
the
a
azimuth.
plicated
recorded
available.
lithology
pensated
are
are
$y.
available;
lithology.
appearing
Neutron
Another
dipmeters,
Dipmeter
logs
addition
on
necessary
photoelectric
measurement.
and,
to
This
thermal
neutron
variable
may
Tools
density-neutron
the
several
several
distinguish
formation
radiation
as
should not be
neutron
porosity-type
Reading
Amodern version
however,
curves
coming
oil
factor
logs
log
index
log,
important
also
the
log
types
single-receiver
for
used.
is
kinds
such,
ratio
display
B,
in
neutron
the
are:
be
from
simultaneously.
measuring
neutron
of the
is
of
back).
(NLL,
group
a
parameters.
curve
(CNL),
decay
porosity scale and the assumed
which
used
bulk
which
logs
If the
of
of wave
They
TDT,
density
normally
of neutron
in
capture
is
standard
The
time
the
computing
time
are
salt water
CNL
and eight-electrode types.
a
tool
porosity curve
A
which
and
valuable
matrix.
rays
dipmeters:
iri
is
end
tools.
cross
High resolution
density,
record
open
to
The
the
caliper
recorded
run
direct
the
result
the
TMD),
normally
formation
records
on
requires
for
hole.
adjunct
is
section
neutron-based
Today’s
four-arm
Normally,
presentation
from
a
LDT
its
dip
a
run
to
the
basic
dipmeters
is
The
three-arm
close
at
formation
which
the
the
and
density-derived
also
indicator
a
tools’
own,
in
type
formation
F
standard
: to as &. well. generated and recorded as (F) curve can be that data, a formation-factor recorded, and, from curve can be generated and an apparent-porosity Additionally, the caliper Gamma ray and Ap correction curve p, bulk density curve two rays gamma and gamma of-operation is to send (because their mode in some parts
of
a gamma
curves:
(HDT)

no
is
particular
hole
neutron
curves
is
dipmeters,
ray
basic
is the litho-density tool
density
cased
attention
measure
same
measurement
includes
drift
measures
to
will
tool
caliper
the
holes.
and
six-arm
record all
com-
outdated
is
actually
formation
referred
combination
be
time.
density
assumed
is
the
(LDT).
that
porosity
is the com-
the
detect

- Gamma ray Spectral Logging Gamma-Ray logging of parts of the world where logging exists about some controversy a and to an attempt ‘Inelastic fast neutron scattering is used in Logging Carbon/Oxygen evaluation arsenal. formation hole run into the testers also allow multiple formation and the formation devices of Several types Test
_
to
Its
a
the
The
than
main
the
“They
use
Borehole
waves
logging
'.Maturally
Dielectric
allow a
indicate
are
pulsed
applicable
‘dielectric
Dielectric
oxygen
has
gas-bearing
sent
having very
temperature,
to
in
borehole
normal.
sedimentology,
borehole
gravitational
all
and
radioactive
"applications are
limited
Logging
requires an
along
porosity
zones,
of
neutron
logging
Gravimeter
time,
in
constant
obvious
occurring
are
and
by
Thus,
brought
wireline
measure
products are associated
different
distinguishes between
wells
Other measurements,
a
and
thorium and potassium,
and
to
Tools
and
tools
spectrometry
limited sample
gravimeter
so
this
of the
with
the wall
families.
formation.
the
very
so
appeal.
proving
acceleration
on
formation
gamma
It
formation
This
dielectric
on,
tool
its
of the
directly the
resistivity
is
measure
can
survey.
everywhere.
certain
Since these
some
(BHGM)
be
measures
shallow
rays
a
elements and
and
can
a
open holes where
material
constant
is
the
formation
in
waters,
relative
related
such as attenuation
may
depth
that
spot
distance
are
the speed
is
of
the
measures
relatively
caused
valuable
constatits;can
exacting set of prerequisites
effectiveness.
not
distinguish
for analysis.
of
of the
distinct types
number
by
formation: From
gamma
dedticed.
from
be
be
new
of
higher
abundance
lighter
and
the
Oil
the
the
parameters.
ray
daughter produicts
available.
or
carbon/ oxygen
uranium
, addition to in tests formation pressure surface of formation fluid to be sucked testers formation
formation
. and to the. one out of These
and
The
service
investigation.
formation waters are
available
speed,
energy
microwaves,
perturbations
These wireline
is used in cased holes and is a natural candidate for those
logs in
Carbon/oxygen
of carbon
and
regarding depth,
mineralogy,
fresh formation waters preclude the use
of three
spectral
from
of
elements and/or their decay
proximity
porosities,
heavier
borehole.
in
distinguished.
water,
electromagnetic
the
or’
fresh.
can
tools’