It told media last week that it would be selling the 120,000 barrel per day refinery to concentrate on larger-scale refining operations, such as the Pulau Bukom refinery in Singapore.
Shell said while its preference would be to divest the asset should a suitable buyer be found, that it would consider converting the plant to an import terminal.
It previously announced plans to do just that at its Clyde refinery in New South Wales, with the conversion process underway.
Shell Australia's downstream vice-president Andrew Smith said it would do its best to manage the transition for workers at the refinery.
"I understand this announcement will be difficult for refinery employees, but Shell will support them through this period of uncertainty," he said.
"Refinery employees in Geelong have made a significant contribution to both Shell and the local community over many years, supporting the economy in southeast Australia."
Shell is aiming to complete a sale of the refinery by the end of 2014.