Search fails to find lost Adelaide camper

A search for a missing Adelaide woman has been postponed without finding any trace of the 55-year-old.

Deborah Pilgrim was last seen early on Sunday morning in Sedan, about 100 kilometres northeast of the city, and police say they are concerned for her welfare.

She was camping in the area with friends when she wandered off.

On Monday, police used a helicopter, mounted patrols, trail bikes and State Emergency Service volunteers in a bid to find her.

The search will resume on Tuesday morning.

A police spokesman said at this stage there was nothing suspicious with Ms Pilgrim simply a missing person.