The Mentapok Association is extensive on mountain ranges composed of basic and intermediate igneous rocks.
It occurs notably:
on the Meliau Range,
on ranges to the east and west of the Mananam Plain,
on the watershed of the Segama and Kinabatangan, and
most extensively in the mountainous half of the Lahad Datu District to the west of Lahad Datu.
Mountainous, with moderate to very steep hills with moderate to very steep slopes. Ridge crests are narrow.