Bulletin of the Geological Society of Malaysia, Volume 61, December 2015, pp. 43 – 47

Late Oligocene and Early Miocene planktic foraminifera from the Temburong Formation, Tenom, Sabah

Junaidi Asis¹*, Muhd Nur Ismail Abdul Rahman¹, Basir Jasin², & Sanudin Tahir¹

¹Geology Programme, Faculty of Science and Natural Resources,
Universiti Malaysia Sabah, 88400 Kota Kinabalu, Sabah, Malaysia
²No. 22 Jalan 2/4F, Section 2, 43650 Bandar Baru Bangi, Selangor, Malaysia
*Corresponding author: junaidi@ums.edu.my, junaidiasis@gmail.com

Abstract: Recently, some planktic foraminifera were successfully retrieved from the shale unit of the Temburong Formation at the Paal River in the Tenom district, southwest Sabah. The area is underlain by the Crocker and Temburong Formations and overlain by alluvial deposits. The Temburong Formation is mainly composed of fine-grained flysch deposits, characterized by rhythmic repetitions of siltstone and shale. Two samples of shale were collected for micropaleontological analysis. The samples were processed according to standard micropaleontology method for foraminifera. A total of eleven species of planktic foraminifera have been identified. The planktic foraminifera comprise Catapsydrax dissimilis, Catapsydrax unicavus, Globigerina ciperoensis, Globigerina connecta, Globigerina eamesi, Globigerina praebulloides, Globigerinoides primordius, Globigerinoides triloba, Globoquadrina venezuelana, Globorotalia bella and Praeorbulina sicana. The planktic foraminifera can be divided into two assemblages representing two biozones namely the Globorotalia ciperoensis Zone (Zone P22) of Chattian age (Late Oligocene) and the Catapsydrax dissimilis-Preaorbulina sicana Zone (N7) of late Burdigalian (Late Early Miocene). The Temburong Formation was deposited at a distal part of a deep-sea fan.

Abstrak: Mutakhir ini beberapa foraminifera plantik telah berjaya diperolehi daripada unit syal Formasi Temburong yang terletak di Sungai Paal di daerah Tenom, baratdaya Sabah. Kawasan kajian didasari oleh Formasi Crocker dan Formasi Temburong dan ditindih oleh endapan aluvium. Formasi Temburong merupakan endapan ‘flysch’berbutir halus yang dicirikan oleh perulangan secara berirama oleh batu lodak dan syal. Objektif kajian ini adalah untuk mengenal pasti foraminifera dan usia himpunan foraminifera plantik. Dua sampel syal diambil untuk analisis mikropaleontologi. Sampel sampel tersebut diproses mengikut kaedah mikropaleontologi yang sah untuk foraminifera. Sejumlah sebelas spesies foraminifera plantik telah dikenal pasti. Foraminifera planktik tersebut terdiri daripada Catapsydrax dissimilis, Catapsydrax unicavus, Globigerina ciperoensis, Globigerina connecta, Globigerina eamesi, Globigerina praebulloides, Globigerinoides primordius, Globigerinoides triloba, Globoquadrina venezuelana, Globorotalia bella dan Praeorbulina sicana. Foraminifera palnktik ini boleh dibahagikan kepada dua himpunan mewakili dua biozon iaitu Zon Globorotalia ciperoensis (Zon P22) berusia Chattian (Oligosen Akhir) dan Zon Catapsydrax dissimilis- Praeorbulina sicana (Zon N7) berusia akhir Burdigalian (akhir Miosen Awal). Formasi Temburong dienapkan pada sekitaran hujung kipas laut dalam.

Keywords: Oligocene, Miocene, planktic foraminifera, Temburong Formation, Tenom