Pustaka Ilmiah Universitas Padjadjaran

Abstrak

Rekonstruksi Lingkungan Pengendapan Batubara Pada Formasi Sajau, Berdasarkan Komposisi Maseral Di Cekungan Berau, Kalimantan Timur

Telah dilakukan pemeriksaan petrografi organik untuk mengidentifikasi komposisi maseral dalam batubara Formasi sajau di bagian timur Cekunagn Berau dalam kaitannya merekonstruksi lingkungan pengendapan batubara dan sumber material organik batubara. Pemeriksaan petrografi menunjukkan bahwa maseral huminit didapat lebih banyak dibandingkan dengan maseral liptinite dan inertinit. Berdasarkan rasio maseral maka dapat diperoleh nilai TPI (Tissue Preservation Index); GI (Gelification Index), GWI (Groundwater index) dan VI (Vegetation Index). Berdasarkan plot nilai TPI, GI, GWI dan VI pada diagram TPI – GI (Diessel, 1986) dan diagram GWI-VI (Calder, 1991 ) memberikan indikasi lingkungan pengendapan batubara untuk seam A-D pada lingkungan fluviatil; seam G-H di lingkungan delta atas (Upper delta plain) dan seam H-M di lingkungan delta bawah (Lower delta plain)

An organic petrographic examination has been carried out to identify the composition of the coal maceral from sajau Formation in eastern part of Berau Basin ini relation to reconstruction the coal depositional environment and organic source input. Petrographic examination of coal seam A – M shown that maceral huminite was dominated compared to liptinite and inertinite. From the rasio of coal macerals can obtained value of TPI (Tissue Preservation Index); GI (Gelification Index), GWI (Groundwater index) and VI (Vegetation Index). Based on the plot of the value of TPI, GI, GWI and VI on the TPI – GI diagram (Diessel, 1986) and GWI – VI diagrams GWI-VI (Calder,1991) the coal deposition environment can be identified. The coal seam A – D were deposited at fluviatile. The coal seam G – H were formed in upper delta plain; while coal seam H – M were deposited at the lower dellta plain.