Characterisation of the weathering profile developed over a porphyritic biotite granite in peninsular Malaysia

Nine stages of weathering of a porphyritic biotite granite bedrock material have been distinguished on the basis of differences of colour, texture and the extent of alteration of mineral grains. Determination of the distribution pattern of the different stabes of weathering of bedrock material within the weathering profile then allowed for recognition of six stages of weathering of the bedrock considered on the scale of the mass. Characterisation of the weathering profile over the prophyritic biotite granite bedrock thus involved recognition and definition of weathering of the bedrock, both on the scale of the hand specimen, i.e. as rock material, and on the scale of the mass, i.e. as rock mass.