Structure variation within two red-brown earth profiles

Abstract

Stereomicroscopic and thin-section studies of structure and fabric features of two red-brown earth profiles from the Riverine Plain of south eastern Australia are assessed in relation to depositional layering and soil formation as suggested by field evidence. Internal fabric in relation to mode of occurrence suggests that some of these features are inherited from, and characteristic of, the original depositional layer whilst others have been formed or accumulated during soil formation subsequent to the cessation of deposition. Trends in the degree of development of these features with increasing depth suggest that the Hanwood profile consists of five depositional layers with evidence for a depositional time break, accompanied by soil formation, at the top of the fourth layer below the present surface. The Deniboota profile includes three depositional layers with evidence for a time break at the top of the second layer below the present surface.