All information on soils were from the Land Resource Study 20 series of books
(Volumes 1 to 5), published by the Land Resources Division, Ministry of Overseas
Development , UK.
Tinagat Association occurs in the Semporna Peninsula, particularly:
the east of the Kalumpang valley,
of Semporna, and
Pulau Timbun Mata
also occurs on Bukit Tinagat, to the northeast of Tawau and to the south of the river in
the upper Kalumpang valley. The association occurs on
mountains and hills of basic and intermediate igneous rocks.