Warta Geologi, Vol. 45, No. 1, March 2019, pp. 6–12
Sedimentology facies of the Tatau Formation,
Tatau-Bintulu Road transact, Sarawak, Malaysia
Ngui Jia Qi¹,*, Abdul Hadi Abd Rahman1, Azfar
Mohamed2
¹Department of Geosciences, Universiti Teknologi PETRONAS,
32610 Seri Iskandar, Perak, Malaysia
2Department of Petroleum Engineering, Universiti
Teknologi PETRONAS, 32610 Seri Iskandar, Perak, Malaysia
*Corresponding author email address: jiaqi.ngui@gmail.com
Abstract:
Sarawak is divided into four zones, namely the West Borneo Basement,
Kuching Zone, Sibu Zone and Miri Zone. The Sarawak Basin in the state covers
both onshore and offshore areas, divided into several geological provinces
which are of Palaeogene to recent age. On the shelf of the basin, sedimentary
succession exceeds 12 km thick (Tan & Lamy, 1990). The study area which is
located between Tatau and Bintulu, consists of sediments which are Neogene in
age. Sedimentology and stratigraphy study was carried out on the Neogene
sedimentary succession at the study area, which stretches around 10 km to 15 km
northeast of Tatau town and southwest of Bintulu town. A total of four outcrops
were studied. The results are based on field survey of the outcrops across the
study area and laboratory analysis of the collected sedimentary samples from
the field. The facies analysis results in the identification of seven facies
which can be are sand-dominated facies and mixed sand and mud-dominated facies.
The sedimentary successions were deposited in an estuarine-inner shelf region.
Keywords:
Sarawak basin, early Neogene, Miri Zone, Tatau Formation
Abstrak: Sarawak
dibahagikan kepada empat zon iaitu West Borneo Basement, Zon Kuching, Zon Sibu
dan Zon Miri. Lembangan Sarawak dibahagikan kepada beberapa wilayah geologi
yang berumur Paleogen sampai sekarang, meliputi kedua-dua kawasan di dalam dan
luar pesisir. Di pelantar lembangan, ketebalan sedimen melebihi 12 km (Tan
& Lamy, 1990). Kawasan kajian yang terletak di antara Tatau dan Bintulu
terdiri daripada sedimen yang berusia Neogene. Kajian sedimentologi dan
stratigrafi telah dijalankan di kawasan kajian yang terbentang di sekitar 10 km
hingga 15 km timur laut dari bandar Tatau dan barat daya dari bandar Bintulu.
Sebanyak empat singkapan telah dikaji. Keputusan adalah berdasarkan kajian di
singkapan dalam kawasan kajian dan analisis di makmal menggunakan sampel yang
dikumpul. Melalui analisis fasies, tujuh jenis fasies telah dikenal pasti di
mana fasies tersebut boleh dikategorikan sebagai fasies yang didominasi oleh
pasir dan fasies yang didominasi oleh pasir dan lumpur. Sedimen telah dienapkan
di kawasan muara-dalaman.
Kata
kunci: Lembangan Sarawak, Neogene awal, Zon Miri, Formasi Tatau
ISSN
0126–5539; e-ISSN 2682-7549
DOI :
https://doi.org/10.7186/wg451201902
