SEDIMENTOLOGY AND STRATIGRAPHY (BIOSTRATIGRAPHY) OF THE KAYAN SANDSTONE FORMATION, LUNDU AREA, SARAWAK – TRANSECT II

This project presents detailed sedimentology and stratigraphy of the Kayan Sandstone
Formation (Upper Cretaceous to Middle Miocene) exposed along the Bau-Lundu Road,
Sarawak. The present work on the Kayan Sandstone Formation is based on previous
research and current work. Field investigation, documentation and sample collection
were carried out in the Lundu area near Kuching, Sarawak. Samples collected were
analyzed for thin section and grain size analysis in the laboratory at Universiti
Teknologi PETRONAS (UTP) and palynology analysis at Biostratex Sdn. Bhd. Four
types of sedimentary facies were recognized within the Kayan Sandstone Formation.
Sedimentary facies identified are i) Trough cross bedding sandstone; ii) Planar cross
bedding sandstone; iii) Interbedded sandstone-mudstone; and iv) Massive mudstone.
From the facies analysis, three facies associations were recognized, which are i) Planar
and trough cross bedding sandstone interbedded with thin mudstone; ii) Planar cross
bedding sandstone interbedded with pebbles; and iii) Thick massive sandstone. Based
on the facies association and laboratory analyses, the Kayan Sandstone Formation can
be interpreted that the sandstones are typically of fluvial environment.