Karakterisasi Resevoir Karbonat Berdasarkan Atribut Seismik dan Analisis Inversi Impedansi Akustik Pada Sub Cekungan Jambi, Cekungan Sumatera Selatan.

Rahmawati, Sabina Nova (2025) Karakterisasi Resevoir Karbonat Berdasarkan Atribut Seismik dan Analisis Inversi Impedansi Akustik Pada Sub Cekungan Jambi, Cekungan Sumatera Selatan. Other thesis, Institut Teknologi Sepuluh Nopember.

Text 5001211054-Undergraduate_Thesis.pdf - Accepted Version Restricted to Repository staff only Download (6MB) | Request a copy

Abstract

Penelitian ini bertujuan untuk mengidentifikasi zona prospektif reservoar karbonat pada Formasi Batu Raja di Lapangan ‘S’ melalui analisis inversi model-based impedansi akustik. Proses dimulai dengan well seismic tie menggunakan ekstraksi wavelet fase nol, menghasilkan koefisien korelasi tinggi 0,94 dan 0,74 antara seismogram sintetik dan data seismik aktual, yang menandakan kualitas pengikatan yang andal. Model awal impedansi dibangun dari log densitas dan kecepatan gelombang P, lalu dikonvolusi dan difilter menggunakan high-cut frequency 5/48 Hz untuk mempertahankan tren frekuensi rendah. Inversi model-based berhasil merekonstruksi informasi frekuensi tinggi dengan hasil misfit relatif –6,02 dB dan energy misfit sebesar 24,99%, menunjukkan akurasi model yang sangat baik serta keseimbangan antara presisi numerik dan generalisasi geologi. Distribusi impedansi akustik (AI) hasil inversi menunjukkan bahwa zona prospektif reservoar berada pada kisaran 30.000–35.000 g·ft/(cm³·s), yang secara umum berkorelasi dengan porositas log >10% dan nilai gamma ray rendah, mengindikasikan litologi karbonat bersih dengan pori efektif maupun pori sekunder. Dua zona utama berada di sekitar sumur SNR-1 nilai AI sekitar 31.000–33.000 g·ft/(cm³·s) dan SNR-2 nilai AI sekitar 33.000–35.000 g·ft/(cm³·s). Dua zona eksplorasi potensial diusulkan di Barat Daya hing ga Selatan area studi dekat SNR-2 dan di Timur Laut hingga Timur area studi dekat sesar besar dan struktur tinggian. Saran diberikan untuk menyempurnakan kalibrasi inversi post-stack melalui integrasi data log terbaru, penggunaan filtering adaptif, dan validasi dengan data sumur tambahan guna meningkatkan akurasi estimasi impedansi dan pemetaan zona reservoir.
====================================================================================================================================
This study aims to identify prospective carbonate reservoir zones within the Batu Raja Formation in Field 'S' through model-based acoustic impedance inversion analysis. The process began with well seismic tie using zero-phase wavelet extraction, resulting in high correlation coefficients 0.94 and 0.74 between synthetic seismograms and actual seismic data, indicating reliable tie quality. The initial impedance model was constructed from density and P-wave velocity logs, then convolved and filtered using a 5/48 Hz high-cut frequency to preserve low-frequency trends. The model-based inversion successfully reconstructed high-frequency information, yielding a relative misfit of –6.02 dB and an energy misfit of 24.99%, demonstrating excellent model accuracy and a balance between numerical precision and geological generalization. The inverted acoustic impedance distribution indicates that the prospective reservoir zones lie in the range of 30,000–35,000 g·ft/(cm³·s), generally correlating with log porosity >10% and low gamma ray values, suggesting clean carbonate lithology with effective and/or secondary porosity. Two main zones were identified around wells SNR-1 AI approximately 31,000–33,000 g·ft/(cm³·s) and SNR-2 AI approximately 33,000–35,000 g·ft/(cm³·s). Additionally, two exploration prospects are proposed in the southwest to Southern part of the study area near SNR-2 and in the Northeast to Eastern part near a major fault and structural high. Recommendations are provided to improve post-stack inversion calibration through integration of updated log data, application of adaptive filtering, and validation using additional well data to enhance the accuracy of impedance estimation and reservoir zone mapping.

Item Type:	Thesis (Other)
Uncontrolled Keywords:	Impedansi Akustik, Inversi Berbasis Model, Karbonat; Acoustic Impedance, Carbonate, Model Based Inversion.
Subjects:	Q Science > QE Geology > QE539.2 Seismic traveltime inversion Q Science > QE Geology > QE539.2.S4 Seismic models
Divisions:	Faculty of Science and Data Analytics (SCIENTICS) > Physics > 45201-(S1) Undergraduate Thesis
Depositing User:	Sabina Nova Rahmawati
Date Deposited:	25 Jul 2025 01:31
Last Modified:	25 Jul 2025 01:31
URI:	http://repository.its.ac.id/id/eprint/121279

Actions (login required)

View Item