Page 33 - Open-Hole Log Analysis and Formation Evaluation

7
2
@
the
and
a
helps
There
index
These
There
the
pulsed
the
azimuth.
a
plicated
available.
recorded
pensated
$y.
are
available;
are
Neutron
appearing
lithology.
Another
dipmeters,
Dipmeter
logs
on
necessary
measurement.
This
thermal
neutron
variable
may
Tools
density-neutron
several
the
formation
several
distinguish
should not be
radiation
neutron
porosity-type
Reading
however,
curves
coming
oil
logs
log
index
log,
important
also
the
log
types
single-receiver
is
used.
for
ratio
kinds
neutron
display
in
the
be
are:
simultaneously.
from
neutron
of
back).
(NLL,
group
parameters.
curve
(CNL),
decay
porosity scale and the assumed
used
which
logs
If the
of
of wave
They
TDT,
normally
of neutron
in
capture
standard
The
time
computing
the
time
are
salt water
and eight-electrode types.
a
CNL
which
porosity curve
A
and
rays
matrix.
dipmeters:
iri
is
end
tools.
cross
record
High resolution
open
to
The
the
caliper
run
recorded
direct
result
the
TMD),
formation
normally
records
on
requires
hole.
for
is
section
Today’s
neutron-based
four-arm
Normally,
from
presentation
a
dip
its
a
run
the
basic
dipmeters
The
is
three-arm
close
at
the
which
formation
and
a
density-derived
indicator
tools’
own,
in
type
formation
F
standard
of
curves:
(HDT)
a gamma

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outdated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

- Gamma ray to the basic density and, as such, is a valuable adjunct lithology Spectral Logging Gamma-Ray is photoelectric factor B, which also measures the to measuring bulk density, the LDT In addition tool Amodern version of the density logging of : to as &. parts of the world where well. generated and recorded as logging (F)
_
Several
to
Its
a
the
The
formation
than
main
“They
the
use
Borehole
waves
logging
types
'.Maturally
Dielectric
allow a
indicate
are
pulsed
‘dielectric
applicable
Dielectric
oxygen
has
gas-bearing
sent
of
having very
temperature,
to
in
normal.
borehole
sedimentology,
borehole
gravitational
all
and
radioactive
"applications are
Logging
limited
along
requires an
porosity
zones,
of
neutron
Gravimeter
time,
logging
in
constant
obvious
occurring
and
are
by
wireline
brought
Thus,
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
with
this
of the
the wall
families.
formation.
the
very
so
appeal.
on
proving
acceleration
formation
gamma
It
dielectric
on,
This
formation
tool
its
of the
directly the
resistivity
is
measure
can
Since these
survey.
certain
everywhere.
some
be
(BHGM)
measures
rays
shallow
a
elements and
and
can
a
open holes where
constant
material
the
formation
is
in
waters,
relative
related
such as attenuation
may
depth
that
spot
distance
are
the speed
the
is
of
relatively
measures
caused
valuable
constatits;can
exacting set of prerequisites
effectiveness.
not
distinguish
for analysis.
of
of the
number
distinct types
formation: From
by
dedticed.
from
gamma
be
be
new
of
higher
abundance
lighter
and
the
Oil
the
parameters.
the
ray
daughter produicts
available.
or
carbon/ oxygen
uranium
formation
, addition to in tests formation pressure surface of formation fluid to be sucked testers formation
and
. and to the. one out of These
The
service
investigation.
formation waters are
available
perturbations
microwaves,
energy
speed,
These wireline
is used in cased holes and is a natural candidate for those
Carbon/oxygen
of carbon
logs in
of three
regarding depth,
fresh formation waters preclude the use
and
mineralogy,
elements and/or their decay
spectral
of
from
proximity
borehole.
heavier
in
porosities,
distinguished.
or’
electromagnetic
water,
the
can
tools’
fresh.