Abstract
The surrounding hills have Plio-Pleistocene formation of mangrove mud, and several marine terraces at different height of 50 ft, 100 ft, and 150 ft. These marine terraces comprise sand deposits, and are covered by giant podzol having thick white sand and iron-humus illuviated horizon. Based on the field observations, geomorphic history of the Baram-Belait river basin was reconstructed. Older peat developed on sand ridges, and younger peat developed on mangrove muds.
