DAFTAR ISI - KARAKTERISASI RESERVOAR BATUPASIR BERDASARKAN DEKOMPOSISI SPEKTRAL, INVERSI SEISMIK MODEL BASED DAN MULTIATRIBUT NEURAL NETWORKS PADA LAPANGAN “EZ”, FORMASI UPPER TALANGAKAR (UTAF), CEKUNGAN SUMATERA SELATAN - Eprints UPN "Veteran" Yogyakarta

  

DAFTAR ISI

  Halaman

  HALAMAN JUDUL .................................................................................... i HALAMAN PENGESAHAN ...................................................................... ii HALAMAN PERNYATAAN KEASLIAN KARYA ILMIAH ............... iii KATA PENGANTAR .................................................................................. iv ABSTRAK .................................................................................................... vi ABSTRACT

   ................................................................................................... vii DAFTAR ISI ................................................................................................. viii DAFTAR GAMBAR .................................................................................... xi DAFTAR TABEL ........................................................................................ xiv DAFTAR LAMPIRAN ................................................................................ xvi DAFTAR ISTILAH ..................................................................................... xvii

  BAB I. PENDAHULUAN 1.1. Latar Belakang ..................................................................................... 1 1.2. Rumusan Masalah ................................................................................ 3 1.3. Maksud dan Tujuan ............................................................................ 3 1.4. Batasan Masalah .................................................................................. 4 1.5. Lokasi dan Waktu Penelitian ............................................................... 4 BAB II. TINJAUAN PUSTAKA 2.1. Geologi Regional Sumatera Selatan .................................................... 6 2.2. Tektonik dan Struktur Geologi Cekungan Sumatera Selatan .............. 8 2.3. Stratigrafi Regional Sumatera Selatan ................................................. 12 2.4. Petroleum System Cekungan Sumatera Selatan .................................. 15 2.5. Stratigrafi Lokal Daerah Penelitian ..................................................... 18 BAB III. DASAR TEORI 3.1. Konsep Metode Seismik Refleksi ........................................................ 20 3.2. Komponen Seismik Refleksi ............................................................... 20 3.2.1. Impedansi Akustik dan Koefisien Refleksi ............................. 20

  3.2.2. Polaritas dan Fasa ..................................................................... 22 3.2.3.

  Well Seismic Tie ........................................................................ 23 3.2.4. Resolusi Vertikal ....................................................................... 25 3.3. Seismik Inversi .................................................................................... 26 3.3.1.

  Inversi Berbasis Model (Model-Based Inversion) .................... 28 3.4. Seismik Atribut .................................................................................... 29 3.5. Dekomposisi Spektral .......................................................................... 32 3.5.1.

  Metode Continous Wavelet Transforms .................................. 32 3.5.2. Tuning Cube ............................................................................. 34 3.5.3. RGB Blending .......................................................................... 35 3.6. Data Sumur ......................................................................................... 36 3.6.1.

  Log Gamma Ray ..................................................................... 37 3.6.2. Log Sonic ................................................................................ 38 3.6.3. Log Neutron Porosity .............................................................. 39 3.6.4. Log Density .............................................................................. 40 3.6.5. Log Resistivity .......................................................................... 41 3.7. Sifat Fisika Batuan ............................................................................... 41 3.7.1.

  Porositas ................................................................................... 41 3.7.2. Permeabilitas ............................................................................ 42 3.7.3. Saturasi Fluida ......................................................................... 43 3.7.4. Densitas .................................................................................... 43 3.7.5. Kecepatan ................................................................................ 44 3.8. Seismik Multiatribut ........................................................................... 46 3.8.1.

   Crossplot Atribut ..................................................................... 47 3.8.2. Multiatribut Neural Networks .................................................. 48 3.9. Tinjauan Umum Mengenai Lingkungan Pengendapan ....................... 51 3.9.1.

   Lingkungan Pengendapan Delta .............................................. 51

  BAB IV. METODOLOGI PENELITIAN 4.1. Data Penelitian ..................................................................................... 54 4.1.1. Data Seismik ............................................................................ 54 4.1.2. Data Sumur .............................................................................. 55 4.1.3. Data Geologi ............................................................................ 56

  4.1.4. Data Chekshot .......................................................................... 56 4.1.5.

  Data Marker ............................................................................. 56 4.2. Perangkat Lunak .................................................................................. 57 4.3. Diagram Alir Penelitian ....................................................................... 58

  BAB V. PEMBAHASAN 5.1. Analisis Zona Target............................................................................ 63 5.2. Analisis Tuning Thickness ................................................................... 65 5.3. Analisis Well Seismic Tie..................................................................... 67 5.4. Analisis Sensitivitas ............................................................................. 70 5.5. Interpretasi Horizon ............................................................................. 72 5.6. Analisi Peta Time Structrure ................................................................ 73 5.7. Analisis Dekomposisi Spektral ............................................................ 74 5.7.1. Analisis Frekuensi ..................................................................... 74 5.7.2. Analisis Iso Frequency ............................................................. 77 5.7.3. Analisis RGB Blending ............................................................. 78 5.8. Analisis Inversi Seismik ...................................................................... 80 5.8.1. Analisis Model Inisial ............................................................... 80 5.8.2. Analisis Pra Inversi .................................................................. 82 5.8.3. Analisis Inversi Model Based ................................................... 84 5.9. Analisis Multiatribut Neural Networks ................................................ 86 5.9.1. Prediksi Volume Gamma Ray ................................................... 87 5.9.2. Prediksi Volume Porosity ......................................................... 89 5.10. Analisis Volume Multiatribut Neural Networks ................................. 92 5.11. Analisis Peta Sayatan ......................................................................... 94 5.11.1. Analisis Peta Sayatan Impedansi Akustik, Gamma Ray dan Porosity ................................................................................... 94 5.12. Analisis Proposed Well ...................................................................... 97 5.12.1. Analisis Proposed Well BM-1 ................................................ 100 5.12.2. Analisis Proposed Well BM-2 ................................................ 101

BAB VI. KESIMPULAN DAN SARAN

  6.1. Kesimpulan ........................................................................................... 104

  6.2. Saran ..................................................................................................... 105

DAFTAR PUSTAKA LAMPIRAN

  

DAFTAR GAMBAR

Gambar 1.1. Peta Lokasi Lapangan EZ (Pertamina, 2016) ..........................

  5 Gambar 2.1. Kerangka Tektonik Pulau Sumatera, Indonesia (Darman and Sidi, 2000) ..............................................................................

  6 Gambar 2.2. Kerangka Struktur Regional Sumatera Selatan (Pertamina, 2016)........................................................................................

  7 Gambar 2.3. Pembagian Subcekungan Sumatera Selatan (Bishop, 2001) ...

  7 Gambar 2.4. Model elipsoidal Jura Awal-Resen (Pulunggono et al., 1992) ....

  9 Gambar 2.5. Subduksi antara lempeng Samudra Hindia dengan Paparan Sunda mulai Jura Awal sampai Resen dan efek yang terkait (Pulunggono et al., 1992) ........................................................

  9 Gambar 2.6. Elemen struktur utama pada Cekungan Sumatera Selatan. Orientasi timurlaut - baratdaya atau utara - selatan menunjukkan umur Eo-Oligosen dan Struktur Inversi menunjukkan Umur Plio-Plistosen (Ginger and Fielding, 2005) 11

Gambar 2.7. Kolom Stratigrafi Cekungan Sumatera Selatan (Agrakoesoemah and Kamal, 2005) ........................................

  15 Gambar 2.8. Konsep Play dan Petroleum System Cekungan Sumatera Selatan (Pertamina, 2016) .......................................................

  16 Gambar 3.9. Kolom stratigrafi lokal berdasarkan data sumur ID-00 ...........

  19 Gambar 3.1. Koefisien refleksi yang dihasilkan oleh perbedaan acoustic impedance (Anstey, 1986).......................................................

  21 Gambar 3.2. Model Impedance (a), wavelet fasa minimum (b), dan wavelet fasa nol (Sim and Bacon, 2014). ...............................

  23 Gambar 3.3. Seismogram sintetik yang diperoleh dari konvolusi RC dan wavelet (Sukmono, 1999) .......................................................

  24 Gambar 3.4. Seismogram Checkshot survey (Sismanto, 2006) ...................

  24 Gambar 3.5. Vertical Seismic Profiling (Sim and Bacon, 2014) ..................

  25 Gambar 3.6. Efek interferensi yang berhubungan dengan batuan dengan AI tinggi yang terletak pada batuan dengan AI rendah (Sukmono, 1999) .....................................................................

  27

Gambar 3.7. Ilustrasi perbedaan antara Forward Modeling (a) dan Inverse Modelling (b) (Sukmono, 2000) ...............................................

  49 Gambar 3.20. Arsitektur PNN (Specht, 1990) .............................................

  67 Gambar 5.4. Proses well seismic tie pada sumur ID-00 ...............................

  65 Gambar 5.3. Ektraksi Wavelet Statistical .....................................................

  64 Gambar 5.2. Amplitude Spectrum dari data seismik Lapangan EZ ..............

  58 Gambar 5.1. Analisis Well to Well Corellation pada zona target .................

  55 Gambar 4.3. Diagram Alir Pengolahan Data ................................................

  54 Gambar 4.2. Basemap survei seismik lapangan EZ dan posisi sumur. ........

  52 Gambar 4.1. Data seismik pada arbitary line ...............................................

  51 Gambar 3.22. Skema Morfologi Lingkugan Pengendapan Delta (Allen and Chambers, 1998) ..................................................

  49 Gambar 3.21. Klasifikasi Lingkungan Pengendapan (Selley, 2000) ............

  47 Gambar 3.19. Prediksi kurva PNN (Russel, 2008) .......................................

  27 Gambar 3.8. Berbagai macam tipe metode seismik inversi (Sukmono, 2016) ......................................................................

  45 Gambar 3.18. Conventional crossplot antara log target dan atribut seismik (Russel, 2008).........................................................................

  45 Gambar 3.17. Beberapa faktor yang berpengaruh terhadap kecepatan gelombang seismik (Sukmono, 1999) ....................................

  43 Gambar 3.16. Skema deformasi batuan terhadap gelombang kompresi ( Vp ) dan gelombang geser ( Vs ) (Goodway, 2001) ...........

  36 Gambar 3.15. Ilustrasi Hasseler Sleeve untuk mengukur Permeabilitas fluida menurut Darcy (Lucia, 2007) ......................................

Gambar 3.14. a) Ruang warna 3D RGB, b) Kombinasi dari warna RGB (Henderson, et al., 2007) ......

  34 Gambar 3.13. Efek ”thin bed” (Partyka et.al., 1999) .................................. 35

  33 Gambar 3.12. Zone of interest tuning cube (Partyka et.al., 1999) ...............

  30 Gambar 3.11. a) Wavelet Gabor -Morlet, b) Serangkaian wavelet Gabor -Morlet (Morlet et.al, 1982) .

  28 Gambar 3.10. Klasifikasi Atribut Seismik (Brown, 1996) ...........................

  27 Gambar 3.9. Diagram alir proses Inversi Model Based (Sukmono, 2000) ...

  68

Gambar 5.5. Analisis Crossplot sumur ID-00 ..............................................

  78 Gambar 5.19. Analisis Pra Inversi pada sumur ID-00 Lapangan EZ ...........

  89 Gambar 5.26. a) Tes operator length 1 hingga 5 point (atas).

  88 Gambar 5.25. Validasi error dengan log target gamma ray menggunakan analisa multiatribut probabilistic neural networks................

   Gamma ray dengan menggunakan 5 kombinasi aribut seismik probabilistic neural networks ..................................

  88 Gambar 5.24. Crossplot antara predicted gamma ray dengan actual

  b) Operator konvolusi 2 point yang digunakan untuk analisis error selanjutnya (bawah) ....................................

  85 Gambar 5.23. a) Tes operator length 1 hingga 5 point (atas).

  84 Gambar 5.22. Slicing Window Horizon Sand 5 ms pada Lapangan EZ .......

  83 Gambar 5.21. Hasil Inversi Impedansi Akustik pada Lapangan EZ ............

  b) Correlation pada Inversi model-based..............................

  79 Gambar 5.20. a) Error plot pada inversi model-based.

  79 Gambar 5.18. Model Inisial Pada Lapangan EZ .........................................

  69 Gambar 5.6. Analisis Crossplot sumur ID-01 ..............................................

  79 Gambar 5.17. Interpretasi Channel dan Fault RGB Blending pada Lapangan EZ .........................................................................

  78 Gambar 5.16. RGB Blending pada Lapangan EZ .........................................

  78 Gambar 5.15. Isofrequency sub band 45 Hz ................................................

  77 Gambar 5.14. Isofrequency sub band 22 Hz ................................................

  76 Gambar 5.13. Isofrequency sub band 15 Hz ................................................

  75 Gambar 5.12. Time Frequency Spectrum dari data seismik Lapangan EZ ........................................................................

  74 Gambar 5.11. Amplitude spectrum dari data seismik Lapangan EZ ............

  73 Gambar 5.10. Amplitude Frequency Spectrum dari data seismik Lapangan EZ .........................................................................

  72 Gambar 5.9. Time Structure Map Pada Lapangan EZ ..................................

  70 Gambar 5.8. Picking Horizon Pada Lapangan EZ........................................

  70 Gambar 5.7. Analisis Crossplot sumur ID-08 ..............................................

  b) Operator konvolusi 1 point yang digunakan untuk analisis

   error selanjutnya (bawah) ..................................................

  90 Gambar 5.27. Crossplot antara predicted porosity dengan actual porosity dengan menggunakan 5 kombinasi aribut seismik probabi-

   listic neural networks ...........................................................

  91 Gambar 5.28. Validasi error dengan log target porosity menggunakan Analisa multiatribut probabilistic neural networks ..............

  91 Gambar 5.29. Probabilistic Neural Networks (PNN) pada penampang Pseudo gamma ray, xline 10159 ...........................................

  93 Gambar 5.30. Probabilistic neural networks (PNN) pada penampang pseudo porosity, xline 10159 .................................................

  94 Gambar 5.31. Peta sayatan impedansi akustik time -5 ms............................

  94 Gambar 5.32. Peta sayatan gamma ray time -5 ms ......................................

  95 Gambar 5.33. Peta sayatan porosity time -5 ms ...........................................

  96 Gambar 5.34. Integrasi Peta Time Structure, Impedansi Akustik, Gamma ray , dan Porosity dan RGB Blending - 5ms ..........................

  98 Gambar 5.35. Peta Overlay Time Structure, Impedansi Akustik, Gamma ray , dan Porosity dan RGB Blending - 5ms. .........................

  99 Gambar 5.36. Peta Daerah Prospek berdasarkan Peta Time Structure, Impedansi Akustik, Gamma ray, Porosity dan RGB

   Blending - 5ms ...................................................................... 100

  

DAFTAR TABEL

Tabel 1.1. Jadwal Pelaksanaan Penelitian .....................................................

  5 Tabel 3.1. Skala penentuan baik tidaknya porositas absolut batuan suatu reservoar (Koesoemadinata, 1978) ..............................................

  40 Tabel 4.1. Ketersedian sumur. .......................................................................

  50 Tabel 4.2. Data Marker Sumur ID pada Lapangan “EZ” .............................. 51 Tabel 5.1. Analisis Tuning Thickness ............................................................

  61 Tabel 5.2. Analisis Tuning Thickness dengan window target .......................

  61 Tabel 5.3. Hasil Proses Well Seismic Tie pada semua sumur ........................

  64 Tabel 5.4. Tabel data yang digunakan dalam proses multiatribut dengan menggunaan 5 jenis kombinasi atribut. .......................................

  82 Tabel 5.5. Tabel data yang digunakan dalam proses multiatribut dengan menggunaan 5 jenis kombinasi atribut. .......................................

  84