A review of soil and geological maps of the Nepean River terraces,NSW

The Nepean River terraces are a sequence of Tertiary and Quaternary alluvial deposits to the west of Sydney, NSW. In the last 85 years over 20 soil and geological maps covering the area have been produced. Errors and interpretations introduced in early regional scale maps were perpetuated for over 40 years despite numerous new editions. Regional scale geological maps in the 1950s and 1960s failed to take account of good detailed work by geographers, soil surveyors and geology students. Detailed geological and soil stratigraphic mapping in the past 10 years drew attention to these problems and has highlighted the important contributions made by the earlier detailed studies. New interpretations can now be tested against a substantial body of data. Contemporary regional soil and geological maps have taken account of these detailed studies and so present a more consistent approach than in the past.