Detective Chief Inspector Garry Watts said the remains were found about one kilometre from her ute, which was found yesterday afternoon on a property off Yuleba-Surat Road in Noorindoo, about 40km north-east of Surat.
Watts said police suspected the remains may be Spies, and they would now undergo forensic examination.
Her next of kin has been notified, he said.
She was last seen on CCTV at a service station in Condamine.
Prior to its discovery, her car was last seen on CCTV driving down Surat’s main street at 11.10am the day she disappeared.
The footage shows the car turning south on the Carnarvon Highway, away from where it was found yesterday.
“How she came to be travelling north we don’t know,” Watts said.
“The landowner doesn’t believe it’s been there longer than 12 days but we’re conducting enquiries as to that.”
Watts said the car was found about two kilometres into the Noorindoo property.
“You would not have seen this vehicle from the road,” he said.
“It wasn’t hidden… but it didn’t stand out.”
The car was found locked and has not been opened.
A number of her belongings, including the pink shirt she was wearing on the day she disappeared, were visible inside.
Watts said the belongings could be seen from outside the car, which did not seem to be in disarray.
The ute was to be towed to Roma to be examined by scenes of crime investigators.
Watts said police were looking into whether the area had been subject to an aerial search.
He said no ground searches had been conducted as the potential search area, approximately 9000 square kilometres, was too vast.
Anybody with information is urged to contact police.
