geophysical course reservoir geophysics pe 22811
DESCRIPTION
geophysicsTRANSCRIPT
3D Reservoir
Characterisation
Geophysical Analysis
Lithology &
Saturation, porosity
Structural/ Strat.
Model
3D Seismic
Interpretation
Reservoir
UTP COURSE : ReservoirGeophysics
AttributesAttributes
Field Economics
Up or Down
Scale ??
Final Reservoir
Sedimentology
Model Characterisation
Model/Static
Fluid Flow Modelling
• Well Test
•Permeability
•PVT/MDT
•Production History
Matching and
Forecast
Facies
Hi Res-Sequence
Stratigraphy &
Environment
Sequence boundary
Maximum Flooding
SurfacePetrophysical/
Wire Line
Property
Model
Reservoir
Simulation
Dynamic
Optimum
Field
Development
Plan
GeostatisticsVariogram
Uncertainity
Final Reservoir
Model
Model
PlanningBlock
Acquisition
Frontier
Exploration
Prospect
EvaluationDrilling
Discovery Volumes AppraisalReserve &
Economic
LIFE OF FIELD
ExplorationExploration
AppraisalAppraisal
Reservoir
Static ModelSimulation
Production
Forecast
PVT
RFT
DST
Development
Plan
Infill
Drilling
Field DevelopmentField Development
EOREORFLOODI2G FLOODI2G
I2JECTIO2I2JECTIO2 SECO2DARY SECO2DARY
RECOVERYRECOVERY
PRODUCER & PRODUCER &
I2JECTORI2JECTOR
Secondary RecoverySecondary Recovery
“Exploration Success Through
Innovative Solution
ACQ/PROCESSI2G - Seismic Data Acquisition- Seismic Data Processing
- Survey and Positioning- Seismic Survey Design
- OBC 4 C / Shear Seismic
GEOPHYSICAL EXPERTISE
SEISMIC
I2TERPRETATIO2
”
SEISMIC METHOD
QUA2TITATIVE
GEOPHYSICS- AVO & Rock Physics- Seismic Inversion
- Structural Modeling & Imaging
Seismic Attribute Analysis
-Reservoir Modelling
-Full Field Development
- Time Lapse Seismic
I2TERPRETATIO2
3D Visualisation
Seismic Interpretation
RESERVOIR
GEOPHYSICS
SEISMIC SECTIO2 FROM 2ORTH VIET2AM
55TOP CARBO�ATE RESPO�SE IDE�TIFIED FROM
GEOLOGICAL FIELD A�ALOG ( �ORTH VIET�AM )
BrazilWest Nile Delta
DEEPWATER IMAGES
66
Courtesy BG plc
L in e 3
5 0 0 m
West Africa
Courtesy BP
Courtesy Enterprise Oil/Shell
GORGE
DEEPWATER GEOLOGICAL MODEL
& SEISMIC RESPO2SE
3D SEISMIC IMAGE
SHALE DIAPIAR
POCKMARK
SEDIME2T
TRA2SPORT
FA2 LOBE
In Deep Water environment hi – res 3D images provide excellent
tool to develop, Calibrate & Test Geological conceptual models.
Sand-rich environment
Petroleum System Processes
Seal RockSeal Rock
ReservoirRockReservoirRock
OilOil
WaterWater
Gas CapGas Cap
EntrapmentEntrapment
24803
120° F120° F
350° F350° FGenerationGeneration
MigrationMigration
RockRock
Source: AAPGSource: AAPG
FORWARD & INVERSE SEISMIC FORWARD & INVERSE SEISMIC PROBLEMPROBLEM
ACQUISITION
SYSTEMS
START
WAVELET
RECOVER
� Structure
� Velocity
� Rock, Fluid, Lithology
END
MO
DELLIN
G
INVER
SIO
N
t
99
EARTH PROPOGATION
EFFECT
CONVOLVE
EARTH MODEL
• Vp, Vs, ρ
• Porosity
• Structure
• Saturation
SEISMIC RESPONSE
DECONVOLVE
RECOVER
GEOLOGY
MO
DELLIN
G
INVER
SIO
N
t
**
THE SEISMIC EXPERIMENTInteraction of Geology & Geophysics
SEISMIC SOURCEGEOLOGICAL
STRUCTURE Depth
Km
Courtesy GX Technology
Various wave modesVarious wave modes
Up-going Wave
1111
Down-going Wave
Identify various wave types:
a) Downgoing wave c) distortion in wave shape
Snell’s Laws of Reflection and
common depth point (CDP)
method
Snell’s Laws of Reflection and
Refraction
Sin i/V1 = Sin r / V2
UnderstandingUnderstanding Wave BehaviorWave Behavior
1313
FAULTED SYNCLINAL STRUCTUREM
OD
ELLIN
G
Depth 2.0
km
3.0
INVER
SIO
N (IM
AG
ING
)
**
1414
SEISMIC DIFFRACTION RESPONSE
MO
DELLIN
G
Time 1.0
secs
2.0
INVER
SIO
N (IM
AG
ING
)
**
3D VISUALISATION OF 3D VISUALISATION OF
GAS FIELDGAS FIELD
Fault
Gas
1515
HorizonWell
Path
CONVOLUTION MODEL OF SEISMIC TRACECONVOLUTION MODEL OF SEISMIC TRACE
→→→→ →→→→ →→→→*
AI(t) RC(t) W(t) S(t
)
M O D E L I 2 G
→→→→ →→→→ →→→→*
I 2 V E R S I O 2
AI : Acoustic impedance RC : Reflection coefficient
W : Wavelet S : Seismic trace
2 2 1 1
2 2 1 1
V VRc
V V
ρ ρ
ρ ρ
−=
+
VELOCITY MODELLI2G
Figure 3.8.31 : Instantaneous Phase Map for E1213 reservoir. Comparison between 1984 and 2002 seismic data
Block S3 Block S3
Base survey (1984) Monitor survey (2002)
SEISMIC IN LIFE OF FIELDSEISMIC IN LIFE OF FIELD
By
DR DEVA GHOSH
Compiled by:
Salbiah Mad Sahad
SEISMIC INTERPRETATIONAL SEISMIC INTERPRETATIONAL
FRAMEWORKFRAMEWORK
By
DR DEVA GHOSH
P.R.S.B
Compiled by Salbiah Bt M
Sahad
Structure & Strat.
Mapping
Geological Models
Concept
3D Seismic
SEISMIC I2TERPRETATIO2 VALUE CHAI2
Recommendation
To Drill
Attribute Analysis
3D Seismic
Well Data
Rock Physics
Prospect
Evaluation
Resources
& Risks
3D VISUALISATION OF GAS FIELD3D VISUALISATION OF GAS FIELD
Fault
Gas
HorizonWell
Path
Depth map
GWC 1417m
Channels viewed using
transparency.
3D Visualisation of Channel Play
M A L A Y B A S IN
Channels maybe
difficult to recognize
on traditional
displays.
SEISMIC WAVE
0- +
High Frequency
10 – 60 Hz (Cycles/sec)
Polarity (Hard)(Soft)
Amplitude (-)
(Reservoir)
2525
0° Phase
90° Phase
180° Phase
Wavelength
λλλλ = v / ƒƒƒƒ
= 3000/30
Resolution = 25 m
= 100 m
Low Frequency
6 – 35 Hz
SEISMIC VARIABLES & ITS ATTRIBUTES
AMPLITUDE � Sand quality NTG
� Porosity
� Fluid & Lithology
2626
FREQUENCY
PHASE� Resolution
� Thin beds/Tuning
� Channel detection � Seismic well match
� Discontinuity faults
� Unconformity
All seismic attributes are linear combination of these three basic variable. While
interpreting seismic data use has to be made of all information derived from these attributes
Class I :
Structural Attributes
Classification of Seismic AttributesClassification of Seismic Attributes
Class 2 :
Spectral Attributes
Flat spot
DHI Indicator : Flat Spot
Class 3 :
Lithology/Porefill
Attributes
Structure and fault volume Interpretation can be
done with transparency in 3D Viz
Semangkok Timur-1
Semangkok Timur-2
Semangkok Timur Deep-1
Ridan-2
EC
EC
Semangkok Timur-1
Semangkok Timur-2
Semangkok Timur Deep-1
Ridan-2
EC
EC
Semangkok Timur-1
Semangkok Timur-2
Semangkok Timur Deep-1
Ridan-2
EC
EC
Semangkok Timur-1
Semangkok Timur-2
Semangkok Timur Deep-1
Ridan-2
EC
EC
Semangkok Timur-1
Semangkok Timur-2
Semangkok Timur Deep-1
Ridan-2
EC
EC
Semangkok Timur-1
Semangkok Timur-2
Semangkok Timur Deep-1
Ridan-2
EC
EC
Stratigraphic channels Imaging on
Spectral Decomposition Abrupt termination on AVO envelope
attribute in a gas reservoir, Sarawak
Amplitude shut off and Phase change on a
producing field in Malay basin
Better imaging at higher frequency
At 45 Hz At 65 Hz
I-25 Channel System
RMS Amplitude Extraction
Diwangsa-1
I-25 Channel System
STRATIGRAPHIC CHA22ELI2GMALAY BASI2
Korbu-1
Analog
Best Chances of Finding
sands are in Point bars3D Seismic Far Offset
Malay Basin Malay Basin StratigraphicStratigraphic Channel PlayChannel Play
Low sinuosity meandering channel
Seismic Image has to be
interpreted in context of
Depositional Environment .
Determine :
Geometry ( L/W/D) Sinuosity
Flow direction
3D Seismic Image Geological Models & Analogues
3D Visualization & Channel (white)
cutting coal layer
ATTRIBUTE ANALYSIS
Seismic Waveform Seismic Waveform FaciesFacies IdentificationIdentification
Seismic Waveform classification using supervised
neural network of geological facies well motif
INTERPRETIVE GEOPHYSICS
SEISMIC IMAGE
CRISP FAULT
IMAGING
3131
COHERENCY
Significance of AmplitudeSignificance of Amplitude
�� Quality of sand: NetQuality of sand: Net--toto--Gross.Gross.
�� Porosity.Porosity.
�� Pore fill: gas, oil or brine.Pore fill: gas, oil or brine.
�� LithologyLithology, hard on soft shale, coal., hard on soft shale, coal.
�� Thin bed Interference AVOThin bed Interference AVO
0.01
0.10
1.00
10.00
100.00
1000.00Perm
eability (m
d) Series1
Fluvial channelsFluvial channels
Proximal lower
shoreface
Distal lower
shorefaceFlood
plain
RESERVOIR QUALITY FROM SEISMICAMPLITUDE & FACIESRESERVOIR QUALITY FROM SEISMICAMPLITUDE & FACIES
POOR……… POROSITY GOOD
…… Seismic
Amplitude
Sedimentology & FaciesRESERVOIR
EFFICIE2CY
0.01
0.00 5.00 10.00 15.00 20.00 25.00
Porosity (%)
Reservoie Efficiency of K Reservoir In a Malaysia Field as aFunction Of Depositional Facies
Poor ………SAND QUALITY…… .’’ Good
POOR……… POROSITY GOOD
Bunga Zetung 1
Bunga Zetung 1
For Data From 20 to 30 Hz
Direct Hydrocarbon Indicators (DHI)Direct Hydrocarbon Indicators (DHI)
2ot all bright spots are DHI.For example: the
following can cause a bright spot
• Hard shale on soft shale.• Hard shale on soft shale.
• Brine sand.
• Anisotropy.
DHIs are best studied in the AVO-Inversion domain.
However, on the stacked section the DHIs have
recognizable patterns that an experienced
interpreter can detect.
• Structural conformity
GAS
3. ) INSTANTANEOUS 3. ) INSTANTANEOUS
FREQUENCY : DROP ( Gas FREQUENCY : DROP ( Gas
Play)Play)
Amplitude InterpretationAmplitude Interpretation: :
Direct hydrocarbon IndicatorsDirect hydrocarbon Indicators
Gas masking at crest
Gas-water contact
1.) STRUCTURE CONFORMABLE 1.) STRUCTURE CONFORMABLE
AMPLITUDE AMPLITUDE
Red – Low
Frequency
35352.) FLAT SPOT OF FLUID 2.) FLAT SPOT OF FLUID
CONTACTCONTACT
2D 3D
4.) AMPLITUDE SHUT OFF 4.) AMPLITUDE SHUT OFF
& PHASE REVERSAL& PHASE REVERSAL
Gas-water contact
KUMANG-1KUMANG-2
W
ES
T
AR
EA
EA
ST
AR
EAMo
del
KUMANG-3_Prop
I II
IIIGWC –1018 m TVDSS
STRUCTURE CO2FORMABLE AMPLITUDES – A DHI
BU-1 B80
BU-3 B80
BU-4 B80
BUD-1 B80
BU-3 B100
BU-3 D10
920
930
940
950
960
970
980
990
1000
BU-1 B80
BU-3 B80
BU-4 B80
BUD-1 B80
BU-3 B100
BU-3 D10
920
930
940
950
960
970
980
990
1000
In all closures related to Structure ( 4 way Dip or Fault )
Amplitudes conform to structure if related to Hydrocarbon
BU-3 D10
BU-4 D10
BU-2 D34
BU-3 D34
BU-4 D34
BUD-1 D34
BU-4 D36
BU-1 D60
BU-2 D60
BU-4 D60
Normal Water Line
Normal Water Line
0.433 psi/ft
Gas Line
0.08 psi/ft
1660 1680 1700 1720 1740 1760 1780 1800 1820 1840 1860 1880 1900 1920 1940 1960 1980 2000 2020 2040
Formation Pressure (psia)
1000
1010
1020
1030
1040
1050
1060
1070
1080
1090
1100
1110
1120
1130
1140
1150
1160
1170
1180
1190
1200
1210
1220
1230
1240
1250
1260
1270
1280
1290
1300
1310
1320
1330
1340
1350
1360
1370
1380
1390
1400
1410
Depth (m TVDss)
BU-3 D10
BU-4 D10
BU-2 D34
BU-3 D34
BU-4 D34
BUD-1 D34
BU-4 D36
BU-1 D60
BU-2 D60
BU-4 D60
Normal Water Line
Normal Water Line
0.433 psi/ft
Gas Line
0.08 psi/ft
1660 1680 1700 1720 1740 1760 1780 1800 1820 1840 1860 1880 1900 1920 1940 1960 1980 2000 2020 2040
Formation Pressure (psia)
1000
1010
1020
1030
1040
1050
1060
1070
1080
1090
1100
1110
1120
1130
1140
1150
1160
1170
1180
1190
1200
1210
1220
1230
1240
1250
1260
1270
1280
1290
1300
1310
1320
1330
1340
1350
1360
1370
1380
1390
1400
1410
Depth (m TVDss)
Gas Water Contact
PRESSURE PLOT
2ear Angle Far Angle
AVO Process
AVO CLASSES
23
AVO RESPO2SE I2 TURBIDITE
2EAR FAR
Both the primary target and a potential prospect show typical Class II type anomaly,
predrill. The primary target was discovery
SEISMIC SECTIO2
EXPLORATIO2 PITFALLAbandoned Clay Channel
FULL STACK AMPLITUDE
Channels
GSM 2008
Stack amplitude cannot
distinguish H.C sand from
clay channel
Importance of Low
Seismic InversionSeismic Inversion
SEISMIC INVERSION
Well AIInverted AI
(10-80 Hz)
Wavelet SeismicAI from Inversion
TRVEAcousticImpedance
Importance of Low Frequency
Inverted AI
(0-80 Hz)
FIG. 2 : (0 - 10Hz) LOW FREQUENCIES OF PRIME IMPORTANCE IN RECOVERING PROPER IMPEDANCE
3D SEISMICGEOLOGY
GEO-STATISTICS
WELL/PETROPHYSICAL
I2VERSIO2OUTPUT
Importance of Low
Frequency 0- 8HzSABAH, KINARUT
LITHOLOGY SECTION
Full Refl
Knr 2S2 Knr 2Knr 1
Shale
SandTD=8300ftah
Base Kinarut sand
Top
Lower
Kamunsu
sand
Knr 3
GWC
Vp / Vs
2.0
1.5
Shl
Snd
SIMULTANEOUS
INVERSION
3D SEISMIC
SAND
SHALE
FIG. 2 : (0 - 10Hz) LOW FREQUENCIES OF PRIME IMPORTANCE IN RECOVERING PROPER IMPEDANCE
3D REPRESE2TATIO2 OF AVO ATTRIBUTE
Vs
POISSON’S
RATIO
SHEAR
IMPEDANCE
B – THI2 BED
RESOLUTIO2
ACOUSTIC
IMPEDANCEVp
θθθθ
RATIO
ELASTIC IMPEDANCE
I2VERSIO2 IMPROVED
SEISMIC RESOLUTIO2
Courtesy CSMP
Coal
Channel
AI EI
CoalCoal--HC Discrimination in Elastic DomainHC Discrimination in Elastic Domain
Gas sand
CoalAI
AI
Coal HC Sand
EI
Q.I. Analysis
DHI
In EI domain coal effect can
Coal Masks HC & Channel
Response
In EI domain coal effect can
Overlap zone
Poisson’s Ratio
EI
Courtesy PETRONAS - PTT
Coal
EI
Seismic Amplitude InversionWORKFLOW
• 3D Seismic
(2ear, Mid, far)
• Well Data
• Rock Physics
• Geological Analysis
ACOUSTIC
IMPEDA2CE
Vs
Vp θθθθ
POISSO2’S
RATIO
SHEAR
IMPEDA2CE
ELASTIC
IMPEDA2CE
Seismic PropertiesVp , Vs ,Sigma, Rho
REFLECTIVIT
Y A.I./ E.I.
Pressure/
Saturation
Porosity
Sand%
Probalistic HC Prediction & Volume
Reservoir /Fluid
Properties
Porosity, Sand %,