3. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 i
Contents
Authorisation for Issue
Preface
Amendment Summary
Section 1 Introduction
1.1 About this Handbook
1.2 Directional Survey and Value Addition
1.3 The Design-Execute Principle
Section 2 Policy and Standards
2.1 Drilling and Well Operations Policy
2.2 Policy Expectations
2.3 Standard Practices
Section 3 Theory
3.1 Surface Positioning
3.2 The Earth’s Magnetic Field
3.3 Position Uncertainty
3.4 Position Uncertainty Calculations
Section 4 Methods
4.1 Multi-Well Development Planning
4.2 Survey Program Design
4.3 Anti-Collision – Recommended Practice
4.4 Anti-Collision – Selected Topics
4.5 Target Analysis
4.6 Survey Calculation
4.7 In-Hole Referencing
4.8 In-Field Referencing
4.9 Drill-String Magnetic Interference
4.10 Survey Data Comparison
4. BP Amoco
BPA-D-004 Directional Survey Handbook
ii Introduction September 1999 Issue 1
Contents (cont’d)
Section 5 Survey Tools
5.1 Inclination Only Tools
5.2 Measurement While Drilling (MWD)
5.3 Electronic Magnetic Multishots
5.4 North-Seeking and Inertial Gyros
5.5 Camera-Based Magnetic Tools
5.6 Surface Read-Out Gyros
5.7 Dipmeters
5.8 Obsolete and Seldom Used Tools
5.9 Depth Measurement
5.10 JORPs
Section 6 Technical Integrity
6.1 What is Technical Integrity ?
6.2 Risk Assessment
6.3 Surface Positioning
6.4 The Directional Design
6.5 Executing the Design
6.6 Survey Data Management
6.7 Performance Review
Appendix A Mathematical Reference
Appendix B Approved Tool Error Models
Appendix C Data and Work Sheets
6. 5#'
'
A-17
5
) A-22
Figure
A.1 Reverse survey calculation A-2
A.2 Geometrical construction of the pedal curve A-7
A.3 The pedal curve and uncertainties in the
north and east directions A-7
A.4 Naming convention for sensor axes A-8
A.5 A ‘bit’s-eye-view’ of the target: the basis of the
BP Amoco target analysis method A-10
A.6 Graphical method of target analysis A-16
A.7 Calculating a no-go area on the travelling cylinder diagram A-18
7. BP Amoco
BPA-D-004 Directional Survey Handbook
A-ii Mathematical Reference September 1999 Issue 1
Appendix A
+*
Contents (cont’d)
A.8 Derivation of the risk-based separation rule A-20
A.9 Behaviour of the risk-based separation rule at
low positional uncertainty A-21
A.10 Behaviour of the risk-based separation rule at
intermediate positional uncertainty A-21
A.11 Behaviour of the risk-based separation rule at
high positional uncertainty A-22
8. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Mathematical Reference A-1
5--%A
5
+*
Some of the equations and formulae
underlying the methods described in
the main part of the Handbook.
(
(
5
'
'
7
[ ]∆
∆
N
MD
I A I A RF= +
2 1 1 2 2sin cos sin cos .
[ ]∆
∆
E
MD
I A I A RF= +
2
1 1 2 2sin sin sin sin .
[ ]∆
∆
V
MD
I I RF= +
2
1 2cos cos .
C
9
20. 7
( ) ( )u u u u u u u0 1 01 0 1 01 0 2 1 01 12 022
1
2
2 2+ = ∠
= ∠ =cos cos .P CP P P P
( )u u u u u0 01 12 02 12= −.
O'
( )u u u u u2 12 01 02 12= −.
28. (7
C T C Thla
h hl ha
hl l la
ha la a
hla nev hla
T
=
=
σ σ σ
σ σ σ
σ σ σ
2
2
2
Thla
I A I A I
A A
I A I A I
=
−
−
cos cos cos sin sin
sin cos
sin cos sin sin cos
0
#
IA
38. (7
C T C Tne
n ne
ne e
ne nev ne
T*
* *
* *
* *
=
=
σ σ
σ σ
2
2
Tne
I A
I A
* tan cos
tan sin
=
−
−
1
0
0
1
'57'07586+F57 +++ 774
!
7
1$
(@σmax @
( )σ σ σ σ σn e n e ne
2 2 2 2 2 2
4
2
+ + − +
1$
(@σmin @
( )σ σ σ σ σn e n e ne
2 2 2 2 2 2
4
2
+ − − +
!
(ψ
ψ
50. ν
χ νp,
2
$
+ν @-.
+ν @.
p.
Example. Find the number of standard deviations at which a 3D error ellipsoid
must be drawn to represent a 95% confidence region, assuming the well position
errors follow a trivariate normal distribution.
Setting p = 0.95 and ν = 3, we find from tables that χ0 95
2
. ,3 = 7.81. The 95%
confidence region is therefore represented by a 2.79-sigma error ellipsoid.
4%
' 98 -:
!
!#7
[ ]σ
σ σ
σ σ
σ σ σA
n ne
ne e
n ne eA A
A
A
A A A=
= + +cos sin
cos
sin
cos sin sin
2
2
2 2 2
2
#
(
/ )
60. +
.
!
7
Inclination = I =cos−
+ +
1
2 2 2
G
G G G
z
x y z
sin−
+
+ +
1
2 2
2 2 2
G G
G G G
x y
x y z
Magnetic Azimuth = Am = ( )
( ) ( )
tan−
− + +
+ − +
1
2 2 2
2 2
G B G B G G G
B G G G G B G B
x y y x x y z
z x y z x x y y
Instrument toolface = τ =tan−
1 G
G
x
y
Figure A.4
Naming convention
for sensor axes
61. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Mathematical Reference A-9
7
G G Ix = − sin sinτ
G G Iy = − sin cosτ
Gz@GI
B B I A B I B Ax m m= − +cos cos cos sin sin sin sin cos sin cosΘ Θ Θτ τ τ
B B I A B I B Ay m m= − −cos cos cos cos sin sin cos cos sin sinΘ Θ Θτ τ τ
B B I A B Iz m= +cos sin cos sin cosΘ Θ
G, B
Θ
62. 7
Gravity Field Intensity@ G G Gx y z
2 2 2
+ +
Magnetic Field Intensity@ B B Bx y z
2 2 2
+ +
Magnetic Dip Angle@sin
.
−
+ +
1
G B G B G B
G B
x x y y z z
5
! 5
'
)
'#
70. Vi
Ui
Xi
Yiσh
σl lij
hij
φij
φi+1
φi+1− φi
Ns
PX
PY
b
Exclusion probability is integrated
over the part of each sector
lying outside the target...
…then summed
over all sectors
geological target
reference point
geological target
boundary
standard error
ellipse
φi
as-surveyed point
of penetration
1
+!
.δ
!+
!
$
.α
K$
( !
! α − °90
M$
(
$
Figure A.5
A ‘bit’s-eye-view’ of
the target: the basis of
the BP Amoco target
analysis method
87. $
7
C T C Ttc
h hl
hl l
tc nev tc
T
=
=
σ σ
σ σ
2
2
88.
89. ( )
( )
pdf
tc
T
tc
t
C
t C t= −
−1
2
1
2
1
π det
exp
( )
=
−
− + −
−
1
2
2
22 2 2
2 2 2 2
2 2 2
π σ σ σ
σ σ σ
σ σ σh l hl
l hl h
h l hl
h hl l
exp
t =
h
l
'704+(5(7=
90.
91. h
l
r
r
→
cos
sin
φ
φ
( ) ( )( ) ( )
( )
pdf r r f
h l
r
h l hl
, exp det
,
,
φ
π σ σ σ
φ
∂
∂ φ
=
−
−
1
2 2 2 2
2
( )( )=
−
−
r
r f
h l hl2 2 2 2
2
π σ σ σ
φexp
( )
( )
f l hl h
h l hl
φ
σ φ σ φ σ φ
σ σ σ
=
− +
−
2 2 2 2
2 2 2
2
2
cos sin sin
94. 7
( )
( )
I pdf r d drij
j
N
j
N
r h l
r
i
i i
s
i
i i
s
ij ij
≈
= + −
−
= +
−
= +
=∞
+
+
∫∫ ,φ φ
φ φ
φ φ
φ φ
φ φ
1 1
1
2 2
h
l
ij
ij
$
97. $
( )I
N
pdf r drij
i i
s
ij
r h l
r
ij ij
≈
−+
= +
=∞
∫
φ φ
φ1
2 2
,
φ φ
φ φ
ij i
i i
s
j
N
= + −
−+1
2
1
98. (
7
( )( )I
N
r r f drij
i i
s h l hl
ij
r h l
r
ij ij
=
−
−
−
+
= +
=∞
∫
φ φ
π σ σ σ
φ1
2 2 2
21
2
2 2
exp
99. BP Amoco
BPA-D-004 Directional Survey Handbook
A-14 Mathematical Reference September 1999 Issue 1
( )( )
( )
=
−
−
− −
+
= +
=∞
φ φ
π σ σ σ
φ
φ
i i
s h l hl
ij
ij
r h l
r
N
r f
f
ij ij
1
2 2 2
2
1
2 2
2 2
exp
( ) ( ){ }
( )
=
− − +
−
+φ φ φ
π φ σ σ σ
i i
s
ij ij ij
ij h l hl
N
h l f
f
1
2 2
2 2 2
4
exp
h lij ij
2 2
+
h
l
ij
ij
7
+
. $ 7 h l ij= tanφ
+
100. . i
7 l V
h U
V V
U U
i
i
i i
i i
−
−
=
−
−
+
+
1
1
1 l ( ) ( )
( ) ( )
l
V U U U V V
U U V V
ij
i i i i i i
i i i i ij
=
− − −
− − −
+ +
+ +
1 1
1 1 tanφ
( ) ( )
( ) ( )
h l l l
l V U U U V V
U U V V
ij ij ij ij ij
ij
ij
i i i i i i
i i ij i i ij
2 2 2 2 2
2
2
1 1
1 1
2
+ = + = =
− − −
− − −
+ +
+ +
tan
cos cos sin
φ
φ φ φ
130. 7
.
$
7
@
( ) ( )
( ) ( )
( )
cos cos cos sin sin
cos sin cos cos sin
sin cos
I A A A A
I A A A A
I A
β β
β β
β
− − −
− + −
− −
7
I @
G
A@ #!
G
β u
interfering
well
no-go
area
0
minimum
allowable
separation
Figure A.7
Calculating a no-go
area on the travelling
cylinder diagram
131. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Mathematical Reference A-19
.
7
σ1@ u C uT
1
σ2 @ u C uT
surf2
2
+σ
7
C1
@ '
(
C2
@
(
σsurf @ C
150. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Mathematical Reference A-21
%
+
6.
Collision Risk (low position uncertainty)
Collision Risk (higher position uncertainty)
σaσb
SaSb
Tolerable Collision Risk
Actual Collision Risk
Minimum Separation
increases as Combined
Position Uncertainty increases
Case 1
d + d
1 2
P
σ 0.242
157. +
.
Figure A.9
Behaviour of the
risk-based separation
rule at low positional
uncertainty
Figure A.10
Behaviour of the
risk-based separation
rule at intermediate
positional uncertainty
158. BP Amoco
BPA-D-004 Directional Survey Handbook
A-22 Mathematical Reference September 1999 Issue 1
σaσb
Sa
Tolerable Collision Risk
Tolerable Collision Risk is
never exceeded - no
Minimum Separation exists
Case 3
d + d
1 2
P
σ 0.399
5
)
163. [ ]D I A j NS
j
S
j
S
j
0 ≤ ≤
Figure A.11
Behaviour of the
risk-based separation
rule at high positional
uncertainty
164. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Mathematical Reference A-23/24
9
+#6.
7
( ) ( )[ ]{ }DL I I I I A AP
i
P
i
P
i
P
i
P
i
P
i
P
i
= − − − −− − − −
cos cos sin sin cos1 1 1 1
1
7
DLS
D D
DLP
TD
P
i
i
M
=
− =
∑
1
0 1
O
$
7
DLS
D D
DLS
TD
S
j
j
N
=
− =
∑
1
0 1
( ) ( )[ ]{ }DL I I I I A AS
j
S
j
S
j
S
j
S
j
S
j
S
j
= − − − −− − − −
cos cos sin sin cos1 1 1 1
1
7
Wellbore Tortuosity = DLS DLSS P−
165. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Approved Tool Error Models B-i/ii
Appendix B
178. MWD - Standard MWD MWD MWD with no (or no known) special
corrections
The model allows for the fact that axial
interference may marginally exceed the upper
limit specified in Section 4.9 when the well is
near to horizontal east/west
MWD + Sag correction MWD+SAG MWD+SG MWD with a BHA deformation
correction applied
Covers all BHA corrections, from simple 2D to
finite-element 3D models
MWD + Short Collar correction MWD+SCC MWD+SC MWD with single station axial
interference correction applied
(4.9)
“Short Collar” is the name of Sperry-Sun’s
correction, but the error model covers all such
MWD + Sag + SC corrections MWD+SAG+SC MWD+SS MWD with both BHA sag correction
and single station axial interference
correction applied
MWD + IHR correction MWD+IHR MWDIHR In-hole referenced MWD (4.8). Assumes a BHA sag correction is applied to
enhance inclination accuracy
MWD + IFR correction MWD+IFR MWDIFR In-field referenced MWD (4.7),
with time-varying field applied. Model
is applicable whether or not Short
Collar type correction is applied.
Assumes a BHA sag correction is applied to
enhance inclination accuracy.
Table B.1 Approved Survey Tool Error Models – MWD (Part 1 of 2)
180. MWD + IFR [Alaska] MWD+IFR:AK MWDIAK In-field referenced MWD in Alaska Model takes account of increased violence
of magnetic field disturbances in Alaska.
Assumes a BHA sag correction is applied
to enhance inclination accuracy
MWD + IFR [Wytch Farm] MWD+IFR:WF MWDIWF In-field referenced MWD at Wytch
Farm
Model takes account of observed low
levels of axial low level interference using
Anadrill BHA components and design.
Assumes a sag correction is applied to
enhance inclination accuracy
MWD + IFR + Multi-station MWD+IFR+MS MWDIMS In-field referenced MWD with multi-
station analysis and correction
(4.9) applied in post-processing
Assumes a BHA sag correction is applied
to enhance inclination accuracy
MWD + Crustal Anomaly corrn MWD+crust MWD+CA MWD where local magnetic field has
been measured (or derived from
aero-magnetic data) and corrected
for, but short-term time variations are
not applied.
Assumes a BHA sag correction is applied
to enhance inclination accuracy
MWD + Crustal + SC corrections MWD+CA+SC MWD+CS Same as MWD + Crustal Anomaly
correction but with single station axial
interference correction applied
Assumes a BHA sag correction is applied
to enhance inclination accuracy
Table B.1 Approved Survey Tool Error Models – MWD (Part 2 of 2)
182. EMS - Standard EMS EMS Electronic multishot with no (or no
known) special corrections
Includes ex-BP “Electronic Single Shots”
model. Assumes large axial interference
errors have been corrected.
EMS + Sag correction EMS+SAG EMS+SG Electronic multishot with a BHA
deformation correction applied
Covers all BHA corrections, from simple 2D to
finite-element 3D models. Assumes large axial
interference errors have been corrected.
EMS + IHR correction EMS+IHR EMSIHR In-hole referenced electronic
multishot (4.8).
Assumes a BHA sag correction is applied to
enhance inclination accuracy.
EMS + IFR correction EMS+IFR EMSIFR In-field referenced electronic
multishot (4.7), with time-varying
field applied. Model is applicable
whether or not Short Collar type
correction is applied.
Assumes a BHA sag correction is applied to
enhance inclination accuracy.
EMS + IFR [Alaska] EMS+IFR:AK EMSIAK In-field referenced electronic in
Alaska
Model takes account of increased violence of
magnetic field disturbances in Alaska.
Assumes a BHA sag correction is applied to
enhance inclination accuracy
EMS + Crustal Anomaly corrn EMS+crust EMS+CA Electronic multishot where local
magnetic field has been measured
(or derived from aero-magnetic data)
and corrected for, but short-term time
variations are not applied.
Assumes large axial interference errors have
been corrected.
Table B.2 Approved Survey Tool Error Models - Electronic Magnetic Multishots
184. BHI RIGS multishot RIGS RIGS INTEQ RIGS multishot surveys
BHI Seeker multishot Seeker MS SKR MS All INTEQ Seeker (5.8) multishot
surveys
Ferranti FINDS multishot FINDS FINDS All Ferranti FINDS (5.8) surveys
Gyrodata - gyrocompassing m/s GYD GC MS GYD GC Older Gyrodata gyro multishots, plus
all battery/memory tool surveys
(RGS-BT)
Replaces ex-BP “Gyrodata multishot into
open hole” model.
Gyrodata - cont. casing m/s GYD CT CMS GYD CC Gyrodata multishot surveys with
continuous tool (RGS-CT) in casing.
OD 13-3/8” or less.
Gyrodata - cont. drillpipe m/s GYD CT DMS GYD CD Gyrodata pump-down multishot
surveys with continuous tool (RGS-
CT) in drill-pipe.
Gyrodata - large ID casing m/s GYD LID MS GYD LC Gyrodata multishot surveys
(gyrocompassing or continuous tool)
in larger size casing strings (greater
than 13-3/8” OD).
Includes an increased misalignment term
Gyrodata – bat/mem drop m/s GYD BM MS GYD BM Gyrodata multishot using
Battery/Memory tool in any
configuration.
Table B.3 Approved Survey Tool Error Models - North Seeking and Inertial Gyro Multishots (Part 1 of 2)
186. Schlumberger GCT multishot GCT MS GCT GCT surveys in casing or open hole. GCT = “Gyro Continuous Tool” (5.8)
SDC Finder - multishot Finder MS FDR MS Finder multishots in casing or drill
pipe
Replaces ex-BP “Inrun” and “Outrun” models
SDC Keeper - casing m/s KPR csg MS KPR CM Keeper multishot surveys in casing.
OD 13-3/8” or less.
SDC Keeper - drillpipe m/s KPR d/p MS KPR DP Keeper pump-down multishot surveys
in drill-pipe.
SDC Keeper - large ID csg m/s KPR LID MS KPR LC Keeper multishot surveys in larger
size casing strings (greater than
13-3/8” OD).
Includes an increased misalignment term
Sperry-Sun G2 multishot G2 gyro MS G2 MS G2 (5.8) multishots in casing, drill
pipe or open hole
Replaces ex-BP “Static” and “Dynamic”
models
Table B.3 Approved Survey Tool Error Models - North Seeking and Inertial Gyro Multishots (Part 2 of 2)
188. Inclinometer (Totco/Teledrift) INC INC Inclination only surveys in near-
vertical hole, including TOTCO,
Teledrift and Anderdrift.
Inclinometer + known azi trend INC+trend INC+TR Inclination only surveys in near-
vertical hole, where formation dip and
experience enables direction of drift
to be predicted.
Replaces ex-BP “Inclinometer (azimuth in
known quadrant)” model
Table B.4 Approved Survey Tool Error Models - Inclination Only Surveys
190. Camera-based mag single shot CB mag SS CBM SS Traditional (mechanical) magnetic
single shot (5.5)
Assumes tandem probes are run and that
both are adequately magnetically spaced.
Replaces ex-BP “PMSS”.
Conventional SRG single shots SRG SRG Optically-referenced gyro single shots
(5.6) Includes SDC Keeper when
used in “siteline reference mode”.
Tool types include SRG and MSRG
(scientific Drilling), Sigma (INTEQ) and
SRO (Sperry-Sun).
Camera-based gyro single shots CB gyro SS CBG SS Traditional surface referenced gyro
tool run on wireline, including “level
rotor” gyros and Sperry-Sun SU3.
Replaces ex-BP “PGSS” model.
Gyrodata - gyro single shots GYD SS GYD SS Gyrodata gyro orientation surveys
SDC Keeper - gyro single shots KPR SS KPR SS Keeper gyro orientation surveys Excludes siteline (ie. surface) referenced
surveys
SDC Keeper – surface ref s/s KPR SR SS KPR SR Keeper gyro orientation surveys,
where azimuth alignment is achieved
by optical referencing at surface.
SDC Finder - gyro single shots Finder SS FDR SS Finder gyro orientation surveys
NS Gyro single shots NS gyro SS NSG SS North seeking gyro orientation
surveys taken with unspecified tool.
Note Gyrodata, SDC Keeper and SDC
Finder have their own models, which
should be used if the tool type is known to
be one of these.
Table B.5 Approved Survey Tool Error Models - Other Single Shot Types
192. Camera-based gyro multishot CB gyro MS CBG MS Traditional optically referenced gyro
surveys run on wireline, including
“level rotor” gyros and Sperry-Sun
SU3 (5.8).
Replaces ex-BP “PGMS” model.
Camera-based magnetic multishot CB mag MS CBM MS Traditional (mechanical) magnetic
multishot (5.5)
Assumes adequate magnetic spacing.
Replaces ex-BP “PMMS”.
Dipmeter or other wireline log Dipmeter DIPMTR Wireline conveyed logging tools with
directional survey capability (5.7).
Schlumberger OBDT, BGT are examples
Sperry-Sun BOSS gyro multishot BOSS gyro BOSS Sperry-Sun BOSS multishot surveys
(5.8).
Table B.6 Approved Survey Tool Error Models - Other Multishot Types
194. Blind drilling Blind n/a Hole intervals where no surveys are
taken
Model assumes well direction deviates
from last known survey at a constant rate.
Errors grow with square of distance drilled.
Unknown survey Unknown n/a Any survey data of unknown or
dubious type
Replaces ex-BP “unknown multishot”
model.
Zero Error model Zero Error n/a Used to set position uncertainty to
zero down to a given depth (eg. side-
track point).
Table B.7 Approved Survey Tool Error Models - Special Models
195. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Data and Work Sheets C-i/ii
Appendix C
235. The function of
the Well Location
Memorandum is
discussed in more
detail in Section 6.3
DGPS and other
surface positioning
systems are
described in
Section 3.1
284. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Data and Work Sheets C-5
WELL LOCATION MEMORANDUM
LOCATION DESIGNATION
This WLM supersedes the following previous locations:
(NB: Any change in shotpoint location must have a new location designation)
Country: Prospect/Field:
Region/State: Lease/PSC/Block:
1. WELL LOCATION DEFINITION (To be completed by Buisiness Unit subsurface and/or reservoir team)
SURFACE LOCATION:
PRIMARY DEFINITION: 3D, 2D, HR Seismic Survey or OTHER* (* Circle appropriate definition)
Survey name: Survey mnemonic:
3D Inline bin, or
Database type name: 2D/HR line number:
3D Xline bin, or
Acquisition contractor year: 2D/HR shot number:
3D bin size (Inline x Xline):
Processing contractor year: or 2D/HR shotpoint interval:
OTHER DEFINITION (eg: template slot No.):
SECONDARY DEFINITION: 3D, 2D or HR* Seismic Survey (* Circle appropriate definition)
Survey name: Survey mnemonic:
3D Inline bin, or
Database type name: 2D/HR line number:
3D Xline bin, or
Acquisition contractor year: 2D/HR shot number:
3D bin size (Inline x Xline):
Processing contractor year: or 2D/HR shotpoint interval:
PRIMARY DRILLING TARGET LOCATION (for non-vertical wells):
PRIMARY DEFINITION: 3D, 2D or HR* Seismic Survey (* Circle appropriate definition)
Survey name: Survey mnemonic:
3D Inline bin, or
Database type name: 2D/HR line number:
3D Xline bin, or
Acquisition contractor year: 2D/HR shot number:
3D bin size (Inline x Xline):
Processing contractor year: or 2D/HR shotpoint interval:
Section 1 completed by: Section 1 approved by:
Signature: Signature:
Date: Date:
Name: Name:
Position/Job Title: Position/Job Title:
285. BP Amoco
BPA-D-004 Directional Survey Handbook
C-6 Data and Work Sheets September 1999 Issue 1
Well Location Memorandum - Page 2 LOCATION DESIGNATION
2. SUBSURFACE DATA(To be completed by Business Unit Subsurface Team)
Attach a separate map sheet to this WLMshowing seismic lines and geological structure around target location
Describe below in words and diagramatically the surface location and it's constraints (give dimensions):
Proposed Location
TOLERANCE Define Surface Location Tolerance(s)
Surface Location Area Diagram
Illustrate shape and size of the zone within which a surface location
would be acceptable and indicate constraints which limit rig
anchoring or manoevring (eg: shallowgas, obstructions, pipelines).
For location(s) derived fromworkstation provide:
Coordinates of surface and primary target locations and two other bins remote fromthe primary target
(one bin with same Inline and one with same Xline bin number as primary target)
Location 3DSurvey Name Bin Size Inline Xline Eastings Northings
Surface:
PrimaryTarget:
Same Inline:
Same Xline:
For surface and target locations based on 2Dor HRseismic provide:
Location 2D/HR Survey Name Point* Line No. Shotpoint Eastings Northings
Surface:
PrimaryTarget:
*Mapped point type (SP, CDP, etc)
Attach extract of relevant 2D and/or HRline fromdatabase listing shotpoint coordinates values for
2kmeither side of proposed location
286. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Data and Work Sheets C-7
Well Location Memorandum - Page 3 LOCATION DESIGNATION
3. WELL LOCATION COORDINATES (To be completed by UTG SURVEY GROUP)
LOCATION COORDINATES
SURFACE LOCATION (Vertical or Deviated well) PRIMARY TARGET LOCATION (Deviated well)
Latitude: Latitude:
Longitude: Longitude:
Eastings: Eastings:
Northings: Northings:
Surface Positioning Tolerance: True azimuth from surface location: degrees
Water depth: Horizontal offset distance: m ft
Ground Elevation:
Geodetic Information:
Datum name: Datum mnemonic:
Ellipsoid name: Ellipsoid mnemonic:
Projection name: Projection mnemonic: Zone:
Data source of coordinates (eg: database name, report, etc):
Surface Location:
Primary Target Location:
Seismic survey positioning systems and horizontal accuracy estimates:
Surface Location Primary Target Location
Positioning System Accuracy Positioning System Accuracy
3D Seismic:
2D Seismic:
HR Seismic:
Other positioning information:
Section 3 completed by: Section 3 approved by:
Signature: Signature:
Date: Date:
Name: Name:
Position/Job Title: Position/Job Title:
Circulation:
D.S. / S.D.E. / D.E. Site Investigation Specialist
Subsurface Team Leader Data Administrator (load to database)
Asset Geoscientists Head of Survey
306. Submit to BP Amoco Survey for checking/approval Location designation:
Date Completed:
Accepted Surface Position Secondary Positioning System Contractors report no.
(Geogs: 2 dec places, Grid: 1 dp (m) 0 dp (ft)) (Geogs: 3 dec places, Grid: 2 dec places) Geodetic Parameters
Lat: ° Long:
°
Geodetic Datum Projection and zone: !
Ref.Stn.1: Name/Country: Associated Ellipsoid !#
307. !#$ !%
Easting:
Northing: Lat. Long. Semi-major axis '
Radius of error: ( ' Primary Positioning System Easting Northing Semi-minor axis
(Geogs: 3 dec places, Grid: 2 dec places) Dist to Ref.Stn. km Reciprocal flattening 1/
System/method for Names of Reference Station(s) used for Ref.Stn.2: Name/Country: Datum Shift
accepted position )*+$, -. Primary Position Lat. Long. From WGS84 to Local Datum
Easting Northing dX: ' dY: ' dZ: (
'
Secondary positioning Dist to Ref.Stn. km rX: rY: rZ: (
system: %#+$, -. Antenna Position: WGS84 Datum Ref.Stn.3: Name/Country: Scale Factor:
//'
Lat: °
Lat. Long. Useful Information / Notes
Rig positioning contractor: 0112 Long:
°
Easting Northing
Job number: Sph. Ht. Dist to Ref.Stn. km 3$4 +
315. Long
°
Sph.Ht.
Coords of rotary: Local Datum
Type of rig: Lat: ° S.D. X: Y: Z:
Vertical datum: Long:
° Offset: Antenna to rotary (Rel. range/bearing)
! 2:% Ellip. Ht. '
°
316. B.M.S.L. Easting:
Coords of rotary: Local Datum
Water or stated
' Northing: Lat. °
depth Vert Datum Long
°
B.L.A.T.
' S.D. X: Y: Z: Easting:
S.D.
RTE A.M.S.L ' Northing S.D.
Diagram Diagram
Rig Hdg
309.7 deg T
R/T
1.0m
56.3 m
GPS Antenna
Rig Hdg
309.7 deg T
R/T
17.4m
42.55 m
GPS Antenna
Completed by:
(block caps) 17
Checked by:
(block caps) =
317. BP Amoco
BPA-D-004 Directional Survey Handbook
C-10 Data and Work Sheets September 1999 Issue 1
WELL PLAN DATA SHEET * delete as appropriate
Rig / Platform / Drill Site* Well
Sheet completed by Date
SURFACE LOCATION planned / actual* Datum/Ellipsoid Projection
Structure reference Description
Lat. N / S* Easting
Long. E / W* Northing
Well reference point Description
Lat. N / S* Easting
Long. E / W* Northing
Offset from structure ref. N / S* E / W*
Elevation (land rig) Elevation (offshore)
Drill datum RT / KB* Drill datum RT / KB*
Drill datum to well ref. pt. Drill datum to MSL
Well ref. pt. to MSL Drill datum to well ref. pt.
TARGET #1 TARGET #2 TARGET #3
Name Name Name
Easting Easting Easting
Northing Northing Northing
Depth TVDss Depth TVDss Depth TVDss
Tolerance Tolerance Tolerance
Survey reference True / Grid* North arrows (diag.)
Grid convergence (T to G) E / W*
Magnetic declination (T to M) E / W*
Magnetic model Date
Correction (magnetic to survey ref.)
Correction (true to survey ref.)
Curved conductors
Drill datum to well reference point
MD TVD North East
N / S* E / W*
Incl. at w.r.p. Azim at w.r.p.
318. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Data and Work Sheets C-11
WELL PLAN DATA SHEET * delete as appropriate
Rig / Platform / Drill Site*
Well
319. Sheet completed by Date
SURFACE LOCATION planned / actual* Datum/Ellipsoid Projection
!# $%% ' ()*
Structure reference Description +
Lat. $°,-%$. N / S* Easting / 0 ,$1
Long. $$°%-. E / W* Northing 0 ,$%1$
323. Offset from structure ref. %- N / S* 1%- E / W*
Elevation (land rig) Elevation (offshore)
Drill datum RT / KB* Drill datum RT / KB*
Drill datum to well ref. pt. Drill datum to MSL 1-
Well ref. pt. to MSL Drill datum to well ref. pt. $%-
TARGET #1 TARGET #2 TARGET #3
Name Name Name
Easting / 0 ,$$ Easting / 0 ,
335. ,
Survey reference True / Grid* North arrows (diag.)
Grid convergence (T to G)
Magnetic declination (T to M)
Magnetic model 77'
Correction (magnetic to survey ref.)
Correction (true to survey ref.)
,1° E / W*
° E / W*
Date 8
,°
,1°
Curved conductors
Drill datum to well reference point
MD TVD North East
$- $%- %1- N / S* - E / W*
G
M
decl. = +0.11
conv. = +2.34
Incl. at w.r.p. 1° Azim at w.r.p. %$$°
336. BP Amoco
BPA-D-004 Directional Survey Handbook
C-12 Data and Work Sheets September 1999 Issue 1
DIRECTIONAL DESIGN CHECK LIST
Rig / Platform / Drill Site Well
Date
Sheet completed by
Checked by
/ Comment
Well Objectives
Document from BU sub-surface team
Updates to well objectives
Well Location Memorandum
Planning File
Well Plan Data Sheet
Survey Program Data Sheet
Proposed well trajectory
BU sub-surface approval of trajectory
Target analysis (1 per target)
Offset well data (surveys, completion diags. etc.)
Initial clearance scan (global scan)
Tolerable Collision Risk Worksheet(s)
Minimum separation calculations
Anti-Collision Instruction Sheet
Magnetic interference prediction
Relief well contingency calculation
Dispensations from Recommended Practice
Wellsite Drawings
Plan view drawings
Vertical section drawings
Structure (spider) plots
Travelling cylinder - global clearance scan
Travelling cylinder - working drawing(s)
Travelling cylinder - wellsite plots
337. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Data and Work Sheets C-13
DIRECTIONAL DESIGN CHECK LIST
Rig / Platform / Drill Site Well
338. Date
Sheet completed by
,
Checked by
+9:
/ Comment
Well Objectives
Document from BU sub-surface team 5 !! !#; =; ,
Updates to well objectives ! !=
=
9!:
Well Location Memorandum 5::!9;
339. Planning File
Well Plan Data Sheet
Survey Program Data Sheet
Proposed well trajectory 8:= %
BU sub-surface approval of trajectory =
9!:
Target analysis (1 per target)
Offset well data (surveys, completion diags. etc.)
9:= 3:!!9 !!3
Initial clearance scan (global scan)
Tolerable Collision Risk Worksheet(s)
Minimum separation calculations + + :=6
Anti-Collision Instruction Sheet
Magnetic interference prediction + + :=6
Relief well contingency calculation
Recommended Practice Dispensation Form(s) ! =):3= 8
Wellsite Drawings
Plan view drawings
Vertical section drawings ?
Structure (spider) plots @6:3
Travelling cylinder - global clearance scan
Travelling cylinder - working drawing(s)
Travelling cylinder - wellsite plots ?
344. BP Amoco
BPA-D-004 Directional Survey Handbook
C-16 Data and Work Sheets September 1999 Issue 1
ANTI-COLLISION INSTRUCTION SHEET
Rig / Platform / Drill Site Well
Date
Sheet completed by
BU authorisation
The instructions given in this sheet are based on: 999
Well plan no. Date Survey program no. Date
and are not otherwise valid.
Wells to be Shut In
Minimum Shut-in Interval
Well name Slot MD from MD to Comment
Minor Risk Wells
Well name TCR* Key Assumptions
*Tolerable Collision Risk
Travelling Cylinder Plots
Plot no. Depth from Depth to Date Comment
Contingency Plans / Special Instructions
345. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Data and Work Sheets C-17
ANTI-COLLISION INSTRUCTION SHEET
Rig / Platform / Drill Site Well
346. Date
Sheet completed by
BU authorisation
A:9 2 ,
The instructions given in this sheet are based on:
Well plan version no. Date
1
347. Survey program version no. Date
1 ,
and are not otherwise valid.
Well Shut-ins
Minimum Shut-in Interval
Well name Slot no. MD from MD to Comment
% $- -
# ?! !6 :) . !:=
, $- ,- : !B
Minor Risk Wells
Well name TCR* Key Assumptions
350. BP Amoco
BPA-D-004 Directional Survey Handbook
C-18 Data and Work Sheets September 1999 Issue 1
DISPENSATION FROM RECOMMENDED PRACTICE
To be used for recording planned violations of standard directional and survey procedures and recommended practices
Rig / Platform / Drill Site Well
Date
Sheet prepared by
Recommended Practice Document
Procedure / Standard to be violated
Details of Dispensation Requested
Justification
Attachments
Technical Assessment / Recommendation Signature / Date / Comment
BU Authorisation
351. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Data and Work Sheets C-19
DISPENSATION FROM RECOMMENDED PRACTICE
To be used for recording planned violations of standard directional and survey procedures and recommended practices
Rig / Platform / Drill Site Well
352. Date
Sheet prepared by
=3C +9:
Recommended Practice Document
:C 89= ::=! !: ) :=
Procedure / Standard to be violated
! !=!C: =):3= 8 (
354. E; $E !=3 $E =):3=
* =
9!:;
Technical Assessment / Recommendation Signature / Date / Comment
A =:3 :=
):3 )=:= ) )66 B
!C; 7
5; %
BU Authorisation
83
=; :C 5 ; $
355. BP Amoco
BPA-D-004 Directional Survey Handbook
C-20 Data and Work Sheets September 1999 Issue 1
NON-COMPLIANCE / NON-CONFORMANCE REPORT
To be used for reporting unplanned violations of standard directional and survey procedures
or unplanned deviations from directional plan or survey program
Rig / Platform / Drill Site Well
Date
Sheet prepared by
Procedure / Standard / Plan / Program document
Procedure / Standard / Plan / Program violated
What happened
Most serious likely consequence
Contributory causes
Action Responsible Date
356. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Data and Work Sheets C-21
NON-COMPLIANCE / NON-CONFORMANCE REPORT
To be used for reporting unplanned violations of standard directional and survey procedures
or unplanned deviations from directional plan or survey program
Rig / Platform / Drill Site Well
357. Date
Sheet prepared by
=3C +9: % %
Procedure / Standard / Plan / Program document
::= !9 := %
+68C:= !9
Procedure / Standard / Plan / Program violated
1. :=
'5G +! := +68C
What happened
'5 68C :=
1. := B = 3 ) ! := !
:9 ::=!
: (7 B=* 6 + )B! !:3 := !69!:!C '5 =:=
(+ 7=* !3 = = 68C !9
Most serious likely consequence
= : B; 63 !8 @6:3 ?! 3::=! B# := $
. := = :C
B; B
359. BP Amoco
BPA-D-004 Directional Survey Handbook
C-22 Data and Work Sheets September 1999 Issue 1
List all the consequences
of collision and the
necessary remedial action
STOP
Use
Conventional
rule - Major
risk
Are the
consequences
of collision
predictable
?
Do the
consequences
of collision include a risk
to personnel or the
environment
?
Estimate the total
cost of collision
Estimate the value
of the planned well
to the BU
Is there a
practical way to
substantially reduce either
the probability of collision or
the severity of the
consequences
?
no
yes
no
no
yes
yes
Prepared by:
Authorised by:
How could the probability of collision or the
severity of the consequences be reduced ?
How might this impact the drilling operation ?
Accepting a finite risk of collision will reduce the
value of the planned well. What reduction, as a
fraction of the total value, are you prepared to
tolerate ? (guideline = 0.05)
Tolerable Collision Risk =
Estimate the total
cost of substantially
reducing the risk
Given the uncertainty in the above estimates, by
how many times must the savings made from not
reducing the risk outweigh the risk itself ?
(guideline = 20)
M =
Tolerable Collision
Risk Worksheet
= 1 in
=
1 : close approach tolerances need not be set
1 :
Tolerable
Collision Risk = 1 in
Use this sheet to justify classifying a well as Minor risk and to
establish the Tolerable Collision Risk for use in risk-based
well separation rule.
Ref. BPA-D-004 (Dir. Svy. H’book) Sections 4.2, 4.3
V =
C =
F =
VF
C
VF
C
VF
C
C
VF
F
M
= =
1
V =
H.Williamson, UTG Well Integrity
Key Assumptions (Elements of the drilling program which are critical to the above analysis)
Scenario Name:
(Be specific. Include all factors which affect either
the cost of collision or the cost of reducing the risk)
Description:
360. BP Amoco
Directional Survey Handbook BPA-D-004
September 1999 Issue 1 Data and Work Sheets C-23
List all the consequences
of collision and the
necessary remedial action
STOP
Use
Conventional
rule - Major
risk
Are the
consequences
of collision
predictable
?
Do the
consequences
of collision include a risk
to personnel or the
environment
?
Estimate the total
cost of collision
Estimate the value
of the planned well
to the BU
Is there a
practical way to
substantially reduce either
the probability of collision or
the severity of the
consequences
?
no
yes
no
no
yes
yes
Prepared by: Stuart Telfer (Directional Engineer)
Authorised by: Richard Harland (Ops Superintendant)
How could the probability of collision or the
severity of the consequences be reduced ?
How might this impact the drilling operation ?
Accepting a finite risk of collision will reduce the
value of the planned well. What reduction, as a
fraction of the total value, are you prepared to
tolerate ? (guideline = 0.05)
Tolerable Collision Risk =
Estimate the total
cost of substantially
reducing the risk
Given the uncertainty in the above estimates, by
how many times must the savings made from not
reducing the risk outweigh the risk itself ?
(guideline = 20)
M =
Tolerable Collision
Risk Worksheet
= 1 in
=
1 : close approach tolerances need not be set
1 :
Tolerable
Collision Risk = 1 in
V =
C =
F =
VF
C
VF
C
VF
C
C
VF
F
M
= =
1
V =
H.Williamson, SPR Well Design
Marnock A01Y Parallel S/T in Reservoir
Sidetracking an existing well (A01Z) by paralleling it through the
reservoir section. Original well is sidetracked below the 13 3/8”
casing drilling 12 1/4” and 8 1/2” hole sections. The original well,
under conventional rules is classed as MINOR risk as it is closed
in and abandoned. Interference occurs in 8 1/2” hole from
4060m to 4590m.
1. Estimated treatment due to contamination from original wellbore and potential mud loss £ 50k
Mud loss is not expected, merely contamination through barite sag in the original hole
requiring treatment to the sidetrack hole system.
2. Potential well control due to reservoir fluid on the highside of the original wellbore £ 200k
(est. 2 days rig time @ £100k/day)
3. Plugback and sidetrack well (est. 6 days rig time @ £100k/day) £ 600k
Moving South edges of the drillers target North
by 10m at entry and 63m at TD would result in:
1. Increased directional control to achieve
smaller targets, cost in extra rig time = 8 days
2. Increased risk of sticking by 25% through
greater sliding requirement, potential impact
of becoming stuck, 12 days rig time.
0.25 x 12 days = 3 days
Total = 11 extra days @ £100k/day
£ 1.10 m
20
0.05
0.065
15
850k
Use this sheet to justify classifying a well as Minor risk and to
establish the Tolerable Collision Risk for use in risk-based
well separation rule.
Ref. BPA-D-004 (Dir. Svy. H’book) Sections 4.2, 4.3
Scenario Name:
(Be specific. Include all factors which affect either
the cost of collision or the cost of reducing the risk)
Description:
Key Assumptions (Elements of the drilling program which are critical to the above analysis)
361. BP Amoco
BPA-D-004 Directional Survey Handbook
C-24 Data and Work Sheets September 1999 Issue 1
List all the consequences
of collision and the
necessary remedial action
STOP
Use
Conventional
rule - Major
risk
Are the
consequences
of collision
predictable
?
Do the
consequences
of collision include a risk
to personnel or the
environment
?
Estimate the total
cost of collision
Estimate the value
of the planned well
to the BU
Is there a
practical way to
substantially reduce either
the probability of collision or
the severity of the
consequences
?
no
yes
no
no
yes
yes
Prepared by: Larry Wolfson 12/6/96
Authorised by: Adrian Clark 15/6/96
How could the probability of collision or the
severity of the consequences be reduced ?
How might this impact the drilling operation ?
Accepting a finite risk of collision will reduce the
value of the planned well. What reduction, as a
fraction of the total value, are you prepared to
tolerate ? (guideline = 0.05)
Tolerable Collision Risk =
Estimate the total
cost of substantially
reducing the risk
Given the uncertainty in the above estimates, by
how many times must the savings made from not
reducing the risk outweigh the risk itself ?
(guideline = 20)
M =
Tolerable Collision
Risk Worksheet
= 1 in
=
1 : close approach tolerances need not be set
1 :
Tolerable
Collision Risk = 1 in
V =
C =
F =
VF
C
VF
C
VF
C
C
VF
F
M
= =
1
V =
H.Williamson, SPR Well Design
Niakuk Segment 3/5 Development Wells
New development wells drilled to segment 3/5 locations
encountering interference with adjacent wells. Shallow
nudges and varying KOPs used to move the interference
depth below the surface casing.
• Collision with a producer/injector results in a side-track of that well: $2-$2.5 million (based on P2-50B)
• Plug back and side-track the drilling well: $200k - $500k
• The cost of delayed production/injection from both wells is estimated at $60 per bopd. NK-10 is a significant
injector that supports 12,000 bopd and the average production from the producers is 3,000 bopd. The cost of
a collision includes delayed production for both wells: - Injector: $900k - Producer: $360k
• Estimated total cost (range): $2.56 - $3.90 million.
0.103
10
$3.9 million
$8.0 million
0.05
Use this sheet to justify classifying a well as Minor risk and to
establish the Tolerable Collision Risk for use in risk-based
well separation rule.
Ref. BPA-D-004 (Dir. Svy. H’book) Sections 4.2, 4.3
Scenario Name:
(Be specific. Include all factors which affect either
the cost of collision or the cost of reducing the risk)
Description:
Key Assumptions (Elements of the drilling program which are critical to the above analysis)
Surface casing set above start of zone of interference (6,600 ft MD)