SEISMIK SEIS MIK STRA STRATIGR TIGRAFI AFI
SEISMIK STRATIGRAFI DAT DATA SEISMI SEISMIK K Di proses & di evaluasi
- SAMP SAMPLI LING NG - HORISO HORISONT NTAL AL - BAW BAWAH PERMUKA PERMUKAAN AN
DETAIL
INFORMASI
- KO KORE RELA LAS SI - DIST DISTRIBU RIBUSI SI STRATIGRA STRATIGRAFI FI
ANTAR SUMUR BOR
DATA SEISMIK Kalibrasi
SEISMIK STARTIGRAFI DETAIL
DATA : SUMUR BOR (Log) (Core) (Biostratigrafi)
SIKUEN STRATIGRAFI
SEISMIK STRA STRATIGRAFI TIGRAFI : ADALAH SUATU SUATU DISIPLIN ILMU YANG BERKAIT BERKAITAN AN DENGAN PENENTUAN HUBUNGAN LITOLOGI DAN STRATIGRAFI BAWAH PERMUKAAN YANG DIPEROLEH DARI DARI DAT DATA SEIS SEISMI MIK K REFLE REFLEKS KSII
AHLI SEISMIK STRATIGRAFI : Mempunyai kemampuan dan pengalaman 1. Seismik Seismik fisika, fisika, Acquisi Acquisition, tion, Processin Processing g 2. Prinsip-pr Prinsip-prinsip insip Startigraf Startigrafi/Str i/Struktur uktur dan Proses-proses sedimentasi 3. Penguk Pengukura uran-p n-peng enguku ukuran ran sumur sumur bor bor dan analisa well-log
FASIES SEISMIK : Adalah kumpulan refleksi seismik yang sifat-sifatnya berbeda dengan kumpulan refleksi seismik lain yang berdekatan dengannya
METODA INTERPRETASI SEISMIK STRATIGRAFI
1. PENENT PENENTUAN UAN FASIE FASIES S SEISMIK SEISMIK Berdasarkan : - Konf Konfig igur uras asii - Kont Kontin inui uita tas s - Amplitudo Amplitudo / phase attributes attributes 2. SELEKSI KANDIDAT KANDIDAT BAT BATAS SIKUEN (SB) DAN BAT BATAS SYSTEM TRACT Berdasarkan : - Gambar Gambaran an Reflek Refleksi si - Termina erminasi si + data pemboran, + biostratigrafi + geokimia
SIFAT-SIFAT REFLEKSI SEISMIK : - KONFIGURASI - AM AMP PLITUDO - KO KONT NTIN INUI UIT TAS - FREKUENSI - INTER INTERV VAL VELO VELOCIT CITAS AS
KRITERIA-KRITERIA UNTUK MEMBEDAKAN TIPETIPE TERMINASI REFLEKSI YANG BERASOSIASI : 1. BA BAT TASAS-BA BAT TAS SA S ATUAN : toplap lap,, onl onlap, ap, off offlap lap,, dow downla nlap, p, tr trunc uncati ation, on, int inter ernal nal (top convergence ) 2. GAMBARAN POLA REFLEKSI DI DALAM SATUAN : subparalel , chaotic, sigmoidal, oblique, o blique, ( paralel, subparalel, divergent ) 3. BENTUK LUAR / BENTUK BENTUK GEOMETRIS DARI SATUAN-SATUANNYA : (sheet, wedge, lens, mound, bank )
TIPE-TIPE TERMINASI REFLEKSI UPPER LIMIT OF THE SEQUENCE (Top (Top Interval) Int erval)
CODIFICATION
Te – eros erosio iona nall trun trunca catu ture re Tt – topl topla ap trun trunc catur ature e C – concordant
A - B C
LOWER LIMIT OF THE SEQUENCE (Base Interval) On - on o nlap Dow - downlap C - co c oncordant O - ob oblique
INTERNAL CONFIGURATION (Contained) P D C W
- paralel - divergent - chaotic - wavy
M Ob Sig Rf
- mounded - oblique - sigmoidal - reflection fr free
IN TERPRET TERPRETAS ASII SEI SEI SMI K -X Line 8 5AR-41 5AR-41 4 (2)
Time Depth Curve - Telaga A1 UBSh
MBS 2
LOWER KEUTAPANG ?
UPPER BAONG
IN TERPRET TERPRETAS ASII SEISM SEISM IK -In Line 8 5AR-40 5AR-40 5 (3) PROP WELL
EDB-1
projected
LOWER KEUTAPANG ?
UPPER BAONG
IN TERPRET TERPRETAS ASII SEISM SEISM IK -X Line 9 0AR-51 0AR-51 6 (4) PROP WELL
EDB-1
projected
LOWER KEUTAPANG ?
UPPER BAONG
INTERPRETASI SEISMIK 90AR-497 (5) PROP WELL
EDB-1
projected
LOWER KEUTAPANG ?
UPPER BAONG
Konsep Konsep Pola Pola Str ukt ur & Horison Horis on ( Case: Line 85ar-408 ) TIMUR LAUT
BARAT BAR AT DAY DAYA A
NP90AR-499 NP90AR-495
LINE 1 TRACE 1
0
-200
-400
-600
-800
-1000
-1200
-1400
-1600
-1800
-2000
-2200
-2400
-2600
1 136
1 270
1 405
NP85AR-401
1 543
1 678
1 811
1 944
1 1077
1 1210
Reflection Geometries: Stratal Terminations at Sequence Boundaries
Stratal Stratal Termination ermination Patterns Patterns
Stratal patterns in a type-1 sequence (the fall in relative sea level to the lowstand lowstand shoreline induces significant erosion on the newly exposed sea floor).
Stratal patter terns in a type-2 sequence (there is no fall in relativ tive sea sea level at the lowstand shoreline and sig signifi nifica cant nt erosi rosio on doe does not not occu ccur). The lowst owsta and syst syste ems tra tract is repl eplace aced by the the shel shelff margin syst syste ems trac tract, t, and the the seq sequen uence bounda undary ry is locat ocate ed wher here the the sta stackin cking g patte ttern cha changes ges fro from prog rograda adatio tional to aggradational.
Profiles across the Brae and Miller Miller Fields Fields,N ,Nort orth h Sea. Sea. (a) Seismic Seismic profile profile and and (b) schematic schematic cross-se cross-sectio ction. n. (Aft (After er W eime eimerr and and Link Link., ., 1999)
Stratal Geometries
Stratal Geometries SB 50
SB 40 T/ Sligo Formation
SB 30 SB 20
LST Prog. Complex
Top-Dwn S
s m 0 0 5
Growth Fault
Louann Salt
6700 ft LR-7
Stratal Geometries
SB 50
T/ Sligo Formation
SB 40 TST SB 30 Buildup SB 20
TST Buildup
Top-Dwn? S
6700 ft
LST Prog. Complex
SB 50
SB 40 SB 30 SB 20
T/ Sligo Formation Grainstone Belt
C-Dwn P
Retrogradation
Top-Dwn O Buildup
Thinning over margin
C/Top-D M 6700 ft LR-8C
PARAMETER REFLEKSI DAN ARTI GEOLOGINY G EOLOGINYA A ( Mitchum dkk,1977)
• Seismic facies parameter REFLECTION CONFIGURATION
• Geologic interpretation -BEDDING PATTERNS -DEPOSITIONAL PROCESSES -EROSIONAL & PALEOGEOGRAPHY -FLUID CONTACTS
REFLECTION CONTINUITY
-BEDDING CONTINUITY -DEPOSITIONAL PROCESSES
REFLECTION AMPLITUDO
-VELOCIT -VELOCITY Y – DENSITY DENSITY CONTRAST CONTRAST -BED SPACING -FLUID CONTENT
REFLECTION FREQUENCY
-BED THICKNESS -FLUID CONTENT
INTERVAL VELOCITY
-ESTIMATION OF LITHOLOGY -ESTIMATION OF POROSITY -FLUID CONTENT
EXTERNAL FORM & AREAL ASSOCIATION OF SEISMIC FACIES UNITS
-GROSS DEPOSITIONAL ENVIRONMENT -SEDIMENT SOURCE -GEOLOGIC SETTING