Search for missing Tasmanian gold miner enters second day_1

A thermal imaging drone and robotic cameras are building 3D imagery of a Tasmanian mine in a bid to locate one of its nightshift workers who went missing during a nightshift on Wednesday.

PYBAR Mining Services chief executive Brendan Rouse told reporters on Thursday afternoon workers at the Henty Gold Mine on the west coast raised the alarm about 4am on Thursday when the man, aged in his late 40s, failed to make contact.

Police said the operation was ongoing after search crews returned to the surface on Thursday and were continuing to treat the operation as a rescue mission.

A section of collapsed dirt was discovered where the man was working.

The ABC reported a team of about 20 people went back down the mine on Friday morning, with the first crew entering the mine about 6am.

AWU national secretary Daniel Walton told the ABC crews were now using a new drone that would build a 3D model of the site.

He said Friday's search would "most importantly give the family some sort of comfort as to the safety of the worker".

"We hope in the next couple of hours, once that analysis is done, we'll be able to get a clear indication as to what the safety and what the footprint looks like from the accident," he said.

Search teams gathered to review the footage from the drone in order to assess their next operational steps.

Fears for the man's safety have grown exponentially since colleagues of the worker raised the alarm when they couldn't contact or find him.

The man was working in the lower levels of the mine in a loader, in an area which was a 20-minute descent, filling a truck on night shift, Mr Rouse said.

The man is believed to be a Queenstown local and has been employed at the mine for about two years.

"Emergency services have been involved, Worksafe Tasmania and the mining inspector are also involved," Tasmanian Premier Peter Gutwein told reporters on Thursday.

"At this stage I can't say much more than that other than our thoughts and prayers are obviously with the missing worker, his family and the other workers."

-with AAP