A soil toposequence on bunya phyllite in Brisbane

Abstract

A common toposequence on Bunya Phyllite in south-east Queensland was studied in detail at a representative site. Four sample profiles on the slope are described, and some physical and chemical properties are given. The clay minerals, derived from the weathering of the quartz-sericite-chlorite phyllite, comprise dioctahedral mica, dioctahedral vermiculite, an interstratification of these minerals, and kaolin. Properties are related to the slope; and the clay-rich horizon of the middle and lower slopes is considered to be formed mostly by in situ weathering. The classification of the genetic unit given by the slope and parent material is discussed.