Page 96 - Open-Hole Log Analysis and Formation Evaluation

is
to
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Use
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Use
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useful
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with
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engineer,
exception.
tools
drillpipe.
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drilled
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programs.
data.
open-hole
the
finder—a
be
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The
evaluate,
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computers.
such
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information
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the
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corrections
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rubber
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with
measurements
and
Additional
slim
determined
size,
completion
tools
guaranteed.
the
snout
specially adapted
induction
more
relevant
rock
, usually badly reservoirs device. Where hydrocarbon and oné porosity ity device muds are natural high-water-loss Also, of one resistiv- needed) generally consist lithology, and information of the radius of investigation formation beyond the the (chosen combinations Logging invades the interpretation when mud filtrate can to Types of Logs objective zone of mudding
short
but
tools
formation.
to
on
from
raw

wall
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problems.
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recorded
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evaluation
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logs.
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as
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type
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Theoretically,
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increased
include:
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logging-
mid,
techniques
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limit
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hole
geophysicist
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borehole
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side
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The
choice
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through
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of the way
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connate
Air-drilled
measurement
adversely
the
measurements.
high-water-loss
decision

formations
shallow
of
contact
waters
water
porosity
to
mud
shallow
borehole
affect
mud
high-water-loss muds
in
resistivity
both'the
influences
washed
true
in
favor
drill
should
can
oil
on
values
devices
holes, which
the
out
tool.

in
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be
program
formations
going down the hole because
drilling
is
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have
and
formations
are
invade.a

through
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choice
previous
and
resistivity,
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friable formations drilled with
can
formation.
of
calculated
of
highly rugose
is normally based
the
induction
In
no
they hang
a
PROGRAM
wells.
designed.
obtain
resistivity,
water-bearing
up
shallow
Likewise,
from
reduce
recovery
holes
formation
prevent
For
on
on the
invariably
so
logging
nonconductive
and
general,
the
the
logging
interest.
on a
nomenclature
holes
effective
Appendix
fluid
formation
of
salinities
salty
and will
ledges
fresh
tool,
excessive
example,
formatioris
consulted
or
deeply as
logging
give
water
drillstem
of the
contact
to
fluid
amplitude
with
in them,
various
later
with
filtrate
/
tools
Nevertheless,
supplies
to
and
with
of
reduce
mud
oil
muds favor
especially
from
‘natural
and/or bridges.
find
logs
resistivity device.
erroneous assumption
the
mask the
frorn
erroneous
from
the
the
in
can
so
a
must be
the
salty
cross
resistivity,