Bulletin of the Geological Society of Malaysia, Volume 1, January 1967, pp. 1-16
Geological Survey of West Malaysia
Abstract: The marine sedimentary rocks of the Kampar area, estimated to be more than 5,500 ft thick, can be lithologically divided into six units, which have been dated by means of fossils. These units, with their thicknesses and ages, are as follows (starting with the oldest): Kim Loong No.1 beds (4,150+ ft, pre-Middle Devonian); Thye On beds (450 ft, Middle Devonian); Kuan On beds (60 ft, Carboniferous); Kim Loong No. 3 beds (330 ft, Lower Permian or Upper Carboniferous?); Nam Loong beds (500 ft, Lower Permian); H. S. Lee beds (50+ ft, Lower to Middle Permian).
The Kim Loong No. 1 beds consist predominantly of dolomites and calcitic dolomites and are distinguished in the field from the grey crystalline calcitic limestones of the Thye On beds. The Thye On beds contain Stringocepha/us perakensis Gobbett and are Givetian in age.
The Kuan On beds are characterised by oolitic limestones interbedded with laminated black shaly limestones and calcitic limestones. Gastropods mainly of the family Sinuopeidae? are present in the shaly limestones.
The Kim Loong No. 3 beds are composed mainly of unfossiliferous sandstones, black pyritiferous shales and shaly sandstones.
The base of the Nam Loong beds consists of massive crinoidal limestone. Overlying this are impure limestones rich in Lower Permian brachiopods.
The H. S. Lee beds are formed of pale limestones. The lower part is Pseudofusulina limestone and the upper part is unbedded reef limestone with Mise/lina sp. and a rich molluscan fauna.