Plio-Pleistocene tectonics and eustasy in the Gippsland Basin, southeast Australia: Evidence from magnetic imagery and marine geological data

Abstract

The Pliocene and Pleistocene sediments of the Gippsland shelf are dominated by mixed carbonates and siliciclastics. From a detailed stratigraphic study that combines conventional marine geology techniques with magnetic imagery, the Late Neogene tectonic and eustatic history can be interpreted and correlated to the onshore section. Stratigraphic analyses of eight oil and gasfield foundation bores drilled to 150 m below the seabed revealed three principal facies types: (i) Facies A is fine-grained limestone and limey marl deeper than 50 m below the seabed, of Late Pliocene age (nannofossil zones CN11-12): (ii) Facies B is a fine-coarse pebble quartz-carbonate sand that occurs 10-50 m below the..