KARAKTER ENDAPAN KUARTER DI LEPAS PANTAI TEPIAN CEKUNGAN SUMATERA TENGAH - P. KUNDUR - Suyatman Hidayat; Indyo Pratomo (JURNAL GEOLOGI KELAUTAN, 2008)
Studi yang dilakukan pada karakter endapan Kuarter di lepas pantai tepian cekungan Sumatera Tengah-P. Kundur mencakup analisis sedimentologi dan stratigrafi terhadap lima belas hasil pemboran yang dilakukan di sepanjang lintasan yang berarah barat - timur di baratlaut P. Kundur. Kedalaman pemboran berkisar antara 8,00 hingga 27,00 m. Studi ini, menunjukkan terdapatnya enam lingkungan pengendapan. Keenam lingkungan pengendapan itu ialah: endapan-endapan material rombakan (Mr), alur sungai (F), limpah banjir (Fp), cekungan banjir (Fb), pantai (Br), dan dekat pantai sampai lepas pantai. Berdasarkan korelasi perubahan lingkungan pengendapan secara lateral dan vertikal, diketahui pula bahwa runtunan stratigrafi tersebut dicirikan oleh berubahnya lingkungan pengendapan yang dikendalikan oleh perubahan iklim dan muka laut, dan mungkin juga oleh tektonik. Selama proses pengendapan, aktifitas perubahan iklim terekam dalam 4 fasa kejadian ialah: (1) minimum, (2)minimum menuju maksimum, (3)maksimum menuju minimum, dan (4)minimum. Kata kunci: Endapan Kuarter, iklim, muka-laut, tektonik The study of the Quaternary sediment characters on offshore of the Central Sumatera basin margin-Kundur Island was based on the analyses of sedimentology of fiveteen boreholes information obtained along the West to East at the northwest of Kundur Island. The penetration of the bore head varied from 8.00 to 27.00 m. This study revealed six deposition environments. These are: mass flow (Mr), river channel (F), floodplain (Fp), floodbasin (Fb), beach (Br), and nearshore to offshore (M) deposits . Based on the correlation of the lateral and vertical variation of the depositional environments, the stratigraphy successions/characterized by the variation of the depositional environments which is controlled by climatic and sea level changes, and also probably by tectonic. During the deposition processes, the activity of climatic changes were recorded in four stages episodes: (1)minimum, (2)minimum to optimum, (3)optimum to minimum, and (4)minimum. Keywords: Quaternary sediments, climate, sea-level, tectonic