Electronic Theses and Dissertation

Industri minyak dan gas bumi (migas) merupakan sektor strategis dalam perekonomian Indonesia, termasuk di Provinsi Aceh. Secara geologi daerah Aceh termasuk kedalam Cekungan Sumatera Utara yang merupakan Cekungan penghasil minyak dan gas bumi terbesar ketiga di Indonesia (Meckel, 2012). Kendati demikian, produksi minyak dan gas bumi pada Cekungan Sumatera Utara terus menurun tiap tahunnya. Oleh Karena itu penting dilakukan peningkatan kajian ekplorasi pada lapangan-lapangan baru salah satunya Sub Cekungan Sigli. Penelitian ini bertujuan untuk mengetahui kondisi geologi daerah penelitian berdasarkan suksesi kronostratigrafi, menganalisis potensi batuan reservoir berdasarkan klasifikasi Tiab dan Donaldson (2012), serta memahami keterkaitan antara kualitas reservoir dengan stratigrafi dan lingkungan pengendapan. Metode yang digunakan mencakup pemetaan geologi, analisis sedimentologi, serta studi petrografi dengan cairan blue dye untuk mengidentifikasi porositas batuan. Hasil penelitian menunjukkan bahwa Sub Cekungan Sigli memiliki kandidat batuan reservoir berupa kandidat batuan reservoir fluvial eosen awal dengan porositas cukup, kandidat batuan reservoir deltaik eosen awal dengan porositas cukup, kandidat batuan reservoir fluvial oligosen awal dengan porositas buruk, kandidat batuan reservoir tidal oligosen awal memiliki porositas cukup, kandidat batuan reservoir outer neritic miosen awal memiliki porositas baik, kandidat batuan reservoir middle-outer neritic miosen tengah memiliki porositas istimewa, serta kandidat batuan reservoir deltaik miosen akhir memiliki porositas baik.

The oil and gas industry represents a strategic sector in the Indonesian economy, including within the Aceh Province. Geologically, Aceh is part of the North Sumatra Basin, which is the third-largest oil and gas producing basin in Indonesia (Meckel, 2012). Nevertheless, oil and gas production in the North Sumatra Basin has experienced a steady annual decline. Consequently, it is imperative to enhance exploration studies in new fields, such as the Sigli Sub-basin. This study aims to determine the geological conditions of the research area based on chronostratigraphic succession, analyze reservoir rock potential according to the Tiab and Donaldson (2012) classification, and understand the correlation between reservoir quality, stratigraphy, and depositional environments. The methodology employed includes geological mapping, sedimentological analysis, and petrographic studies utilizing blue dye injection to identify rock porosity. The results indicate that the Sigli Sub-basin contains several reservoir rock candidates: Early Eocene fluvial reservoir candidates with fair porosity, Early Eocene deltaic reservoir candidates with fair porosity, Early Oligocene fluvial reservoir candidates with poor porosity, Early Oligocene tidal reservoir candidates with fair porosity, Early Miocene outer neritic reservoir candidates with good porosity, Middle Miocene middle-outer neritic reservoir candidates with excellent porosity, and Late Miocene deltaic reservoir candidates with good porosity.