On the Adelie Coast continental margin, a multichannel seismic survey has revealed the presence of a thick sedimentary basin, beneath the outer continental shelf and upper slope, that may exceed 6000 m. This basin results from the creation and evolution of a continental margin, initiated about 100 million years ago from the separation of Australia and Antarctica. Beneath the outer shelf, which is 400-500 m deep, the sedimentary series consists of four units separated by three major unconformities:

- A prerift unit including a Precambrian basement, possible Paleozoic and early Mesozoic sediments and a Mesozoic synrift sequence;

- An early postrift unit, ranging in age from Cenomanian to Eocene, assumed to consist mainly of fluviatile to deltaic clastics;

- An Upper Eocene to Oligocene unit in a shallow marine environment;

- A Neogene glacial prograding unit.

The early postrift unit is considered to be a promising petroleum target based on comparison to other passive margins.