Report is result of 2 years field and office research. Principal results are: (1) Little or no possibility of unmetamorphosed Cambrian shelf type sediments below the basin. (2) Upper Devonian - Lower Carboniferous sequence much thicker than previously thought (over 18,000 feet. of flysch and molasses type sediments deposited in marginal trough formed by Tabberabberan Orogeny). The sequence is described in some detail. (3) Cretaceous occurrences around and in the basin are reviewed and some conclusions drawn as to the possible extent and thickness of the Cretaceous section in the basin. (4) Tertiary outcrops along the lower reaches of the Murray were studied in detail, and revealed a series of faults and monoclines with a complex history of Tertiary movement. Includes 8 plans (1) and (2) Geological map of Murray Basin, 16 mile scale (3) Map of Mootwingee-Koonenberry area, 4 mile scale (4) Geological map of area west of Cobar, 2 mile scale (5) Northern Grampians, 1 mile scale (6) Mootwingee-Wertago area, 1 mile scale (7) Upper Devonian-Lower Carboniferous structure, 48 mile scale (8) Mesozoic-Tertiary structure of Murray Basin, 16 mile scale.