Down hole measurements in oilfield operations

Tor Eiane

Geoscience Manager
Baker Hughes Norway

© 2010 Baker Hughes Incorporated. All Rights Reserved.

 LWD Development

Fluid Analyzer & Sampling

Seismic While Drilling
ZoneTrak-G
Acoustic Positioning
Wired Pipe
ZoneTrak-R
Azimuthal Caliper
BCPM II

Complexity
Azimuthal Propagation Resistivity
DeepTrak
StarTrak
MagTrak
Sara II
Co-Pilot
TesTrak
LithoTrak
SoundTrak
Triple Combo MPR

Resistivity Gamma
Teleco Directional Gamma
MWD

1975 1980 1985 1990 1995 2000 2005 2010 2015

Design Phase

2 © 2010 Baker Hughes Incorporated. All Rights Reserved.

 Electronics inside a LWD tool

3 © 2010 Baker Hughes Incorporated. All Rights Reserved.

 LWD tool Wiring

4 © 2010 Baker Hughes Incorporated. All Rights Reserved.

 Q-packing of electronic boards

5 © 2010 Baker Hughes Incorporated. All Rights Reserved.

 Drilling Optimization

• Wellplanning
• Technichal solution evaluation
– Bit, BHA, Mud, motor, AutoTrak, MWD/LWD suite
• BHA engineering
• Pre-Run in hole preparations
– Pre-checking of equipment
– Programming of equipment
• Operational Performance

6©
200
 Why is Drilling Dynamics Important?
Poor drilling dynamics management can cause:
• ROP reduction
• Accelerated fatigue damage to BHA tools and drill pipe
– Twist off
– Wash Out
– Backing off connection / over torque
– Uneven wear on BHA / drillstring
• Borehole enlargement / wellbore instability
• Premature failure to:
– Drill bit
– MWD/LWD/RSS equipment
– Surface equipment
• Poor directional control
• Poor
7 logging response
 Drilling Dynamics Behavior

Dynamics behavior is a function of / influenced by:

• Rock / bit interaction and/or borehole/drill string interaction

• Drilling practice (WOB/RPM relationship, mud pumps etc)
• Natural resonant excitation frequency
• Combination of the above  Complex

8
Three Modes of Vibration

Lateral
Acceleration
Lateral
Vibration
Whirl

Stick-Slip
Torsional
Vibration
Tangential
Acceleration

Bit Bounce

Axial Vibration
Axial
Acceleration

9
 Vibration

• Axial • Lateral
– “Bit Bounce” – Contact with bore
– Does not have hole wall
to be generated – Whirl
by the bit
 Stick Slip

• Ranges from
• Torsional Oscillations
– Bit / BHA always keeps moving
• Stick Slip
– Bit / BHA stops moving
• Backwards Rotation
– Bit / BHA rotates backwards
 Whirl

• Whirl
– With VSS we can only infer it’s
presence
Stick-slip Mitigation after Positive Drill Break
Whirl Visualization
ORD sub - Optimized Bulk Density

- Optimized Bulk Density

- Azimuthal Density /PE
- 3 axial acoustic Caliper
- Azimuthal Caliper

15
What is Optimized Bulk Density

• Baker Hughes has a unique method of reducing the

impact of the borehole on the density measurement

Stand-off Binning

16
Density Stand-off Binning “Proof of Technique”

r
BDC5M
dr
DRH5M Bin Time
BT5M Bin Weight r-
Optimised
1.65 G/CC 2.65 -0.5 G/CC 0.5 0 MS 30000

BDC4M DRH4M BT4M WEIGHT4

r - Bin 1
1.65 G/CC 2.65 -0.5 G/CC 0.5 0 MS 30000 0 1

BDC3M DRH3M BT3M WEIGHT3 BDC5M

r - Bin 5
1.65 G/CC 2.65 -0.5 G/CC 0.5 0 MS 30000 0 1 1.65 G/CC 2.65
BDC2M DRH2M BT2M WEIGHT2 BDC1M
DEPTH
METRES 1.65 G/CC 2.65 -0.5 G/CC 0.5 0 MS 30000 0 1 1.65 G/CC 2.65

BDC1M DRH1M BT1M WEIGHT1 BDCM

1.65 G/CC 2.65 -0.5 G/CC 0.5 0 MS 30000 0 1 1.65 1.65
G/CC 2.65

2.65

CASING

RAT
HOL
E
NEW
17 HOL
E
Azimuthal Density image

18
Applications of Acoustic Data
DT Density

Rock Mechanics
Borehole Stability
Anisotropy

Real-Time
Seismic Tie
AVO Analysis

Dt - Dtmtx
f=
Acoustic Dtf - Dtmtx
Pore Pressure Porosity
Actual
Prediction
Secondary
Predicted Porosity
19
SoundTrak - Source Excitation Modes
Monopole Dipole Quadrupole
 Dipole Quadrupole
Data Example

Comparison:
Shear slowness from
dipole and
quadrupole modes

8 ½” Bit, OBM

21
Acoustic Shear Measurements - Quadruple

“Industry Unique”
Quadrupole
Excitation

Slow Shear
(640 μs/ft)

22
LWD formation pressure testing

19/10/2012
SmartPad™
• Pad ejection phase critical
– Intelligent controlled pad ejecting system to avoid damaging
the formation and ensure sealing during the entire sequence

1 2 3

 Formation break down during draw down

24
 Shortened test time – SmarTest™
 Smooth draw down
 Avoid shocking formation
 Avoid sanding / plugging

 More reliable mobility and pressure

data

25
Data Quality - Fluid Gradient – Well 1a

1.5 bar

26
 Fluid Sampling and Analyzing While Drilling

27 © 2010 Baker Hughes Incorporated. All Rights Reserved.

Early versus Late Pressure Test Example

• flowing gas versus flowing filtrate

LWD WL
early late
high mobility (gas) low mobility
(filtrate)

Draw- Time Over- Avg. Estimat Estimate

down since balan Mobili ed d
volum drilled ce ty viscosity Permeabi
e hrs mD/c (180 lity
P degF)

LWD 10 cc 5 hrs 100 15925 0.047 709 mD

psi cP (gas)

WL 10 cc 100 hrs 375 580 0.5 cP 290 mD

psi (filtrate)
LWD Sampling
Exit to
Wellbore
Sampling Tanks

Sample Pressure Gauge Draw Down Pump

Fluid Analyzer Quartz Pressure Gauge

Sealing Element
 Density and Viscosity

Baker Hughes In-Situ Fluids eXplorer (IFX)

and LWD FAS

30 © 2009 Baker Hughes Incorporated. All Rights Reserved.

 Sound Speed

Baker Hughes In-Situ Fluids eXplorer (IFX)

and LWD FAS

31 © 2009 Baker Hughes Incorporated. All Rights Reserved.

 Real time data (Time since drilled 1.5 hrs)

10/19/2012

32 © 2010 Baker Hughes Incorporated. All Rights Reserved.

Single Phase Sampling
Sample Volume

Sample volume vs Initial N2 Charge

900
• Linear
800
relationship

S a m p le v o lu m e c c
700
with N2 600

filling 500

pressure 400
300
200
100
0
0 500 1000 1500 2000 2500

N2 charge psi
 10/19/2012

35 © 2010 Baker Hughes Incorporated. All Rights Reserved.

 Magnetic Resonance While Drilling

36
Magnetic Resonance Imaging

 Clinical MR images are determined

from -
– Quantity of 1H present in the specimen
– Relaxation times present in the tissue
 Hospital
– Large Machine, small sample, lots of time.
 Wellbore
– Small Machine, large sample, log fast.
NMR: An Unusual Use!
Alcohol NMR
scanning.
Some bottles of wine are worth thousands of
dollars. But if oxygen has leaked past the
cork, it could be thousand-dollar vinegar -- and
there’s no way to tell without opening the
bottle. Now chemists at the University of
California, can check an unopened bottle for
spoilage using nuclear magnetic resonance
(NMR), the same technology used for medical
MRI scans.

NMR scanning allows the

detection of vinegar to as low as
0.1g/l. wine is considered off at
0.3g/l
LWD Magnetic Resonance

Magnetic Resonance
- Total Pore Volume
- Free Fluid
- Bound fluids: Cap & Clay
- Permeability Indication

39
 Measurement Sequence
TE : Inter-Echo Spacing

TW : Wait Time RF Pulses

Echo Signals
NE : Number of Echos

Excita-
tion Refocus Refocus Refocus Refocus Refocus
Amplitude

TW TE Time
NE : 1000
TE : 0.6 ms F : 500 kHz
TW : 6 s G : 2.0 G/cm

40
 Echo Train T2 Distribution

20 Porosity
Multi- 4 T2 cutoffs
Echo Amplitude

Partial Porosity
15 Exponential 3

10
Decomposition 2

5 1

0
0 100 200 300 400 500 0.1 1 10 100 1000
Time (ms) T2 (ms)

Dry Clay- Capillary

Matrix Rock bound bound Movable water
Clay
water water
Heavy Medium Light
Oil Oil Oil
Volumetrics

41
Field Gradient: Benefits & Drawbacks

High Gradient Low Gradient

BRF BRF

Diffusion Effect No Diffusion Effect

42
Field Gradient: Benefits & Drawbacks

Wireline LWD
High Gradient Low Gradient

BRF BRF

Vibration Vibration
Intolerant Tolerant
 Magnetic Resonance While Drilling
Proving the Value of MR-LWD Data
Major Operator – UK, North Sea
Well Data
 Location: West of Shetland, UK
 Data: Apr, Oct, Dec 2006
 Hole Size: 8 ½” section
 Well Type: Directional
 Formation: Sand – Shale

Objectives:
 Prove the additional value of Magnetic Resonance
while drilling data by providing permeability index
curve, independent Sw, and net-to-gross

Challenges:
 Acquire T2 echo trains while drilling irrespective
of drilling vibration and tool movement
 Application of MR-LWD with no influence on
drilling operation

Results:
 Accurate MR porosity and permeability index to
better characterize the reservoir flow units
 Independent HC saturation from late T2 peak
Electrical imaging

• Wireline Electrical imaging: Formation

contact by means of pads pressed
against the borehole wall
• While drilling: Standoff is essential to
prevent wear
Measurement electrode with
Isolation

Guard electrode

Isolation
 Stabilizer to manage standoff Return
 Single Sensor on a rotating
collar - 100% borehole coverage
 Focused like a Laterolog
 Magnetometer keyed
 Broad Range of RPM and ROP
45
StarTrak fabrics / facies

Injected
sandstone

Plant roots in
fossil soil

46
 StarTrak Fracture Characterisation

Feet

Sub-Horizontal Bedding Fault

47
Wellbore Stability / In-Situ Stress
SHmax

Shmin

Breakout
(Shmin)
Drilling-induced
Tension Fractures
(SHmax)
Reservoir characteristics

•Permeability 5-10
Darcy
•Fluid density 0.894
g/cc
•Porosity ~33 PU
Reservoir Navigation
Injectite
OpenHoleSideTrak in Reservoir

OHST

1.St mulitlateral

Main
Troll – Star Fish Multi-Lateral
 Questions

54 © 2010 Baker Hughes Incorporated. All Rights Reserved.