A $930,000 seismic program to search for natural gas pockets around Carmacks is scheduled to begin later this month in the middle of the highway.

Project geologist Maurice Colpron of the Yukon Geological Survey said today specially-equipped trucks with strings of seismic cups will be recording the geological makeup along the Robert Campbell and Klondike Highways and the Mount Nansen Road.

He explained in an interview the Whitehorse trough consists of rocks that are primarily Jurassic in age, or approximately 170 million to 190 million years old.

'And these rocks are expected to be a potential host for gas, so it is an oil and gas-directed project,' Colpron said.

'In doing the seismic study, what we are hoping to see is whether there are big faults or folds in the subsurface that could be traps for oil and gas.'

Gas is the primary target, he explained.

The work is expected to produce a glimpse of what lies below to a depth of 10 kilometres.

Colpron said preliminary data should be available by next November's annual Yukon Geoscience Forum.

The Geological Survey of Canada is putting up $700,000 for the project while the Yukon government is funding the remaining $230,000.

The bulk of the cost, he said, is to cover the actual seismic work.

Colpron said interest in the potential for pockets of natural gas in the Whitehorse trough first surfaced in the 1970s but has taken on new life with talks about the construction of natural gas pipelines in the North.

Seismic work along the Campbell Highway will include the section from Little Salmon Lake to Carmacks, up the Mount Nansen Road and along the Klondike Highway for 15 or 16 kilometres north of Carmacks.

The Robert Campbell and Mount Nansen Road were chosen because they pretty much run at right angles to the trough, and will provide a full cross section from the trough's east-west boundaries.

Colpron said the work involves setting out recording cups to the front and rear of a specially-equipped truck that sends out vibrations and records the response.

It will likely involve restricting the highway to one-lane traffic when the work is underway, he said.

Colpron said the seismic work is meant to provide a baseline of information for companies or individuals who may be interested in exploring the area further.

The Yukon government announced two years ago it would like to include the north end of the Whitehorse trough in future land sales for oil and gas exploration.

The three land sales released by the Yukon government to date have been in the area of Eagle Plains and the Peel Plateau.

John Masterson, director of the Yukon's oil and gas branch, said today the fourth land sale is scheduled for this spring, and the government is in discussions with first nations regarding the area. But it has been decided the area will again be in the northern part of the territory, he said.

But the seismic work around Carmacks, Masterson added, will provide a significant amount of new information companies will be able to use when considering exploration targets.

He said there is virtually no information regarding the oil and gas potential of the Whitehorse trough.

'It is basically thought that the north end of the Whitehorse trough is probably the most prolific but that has yet to be confirmed.'

A government land sale involves identifying a general area of interest, then calling on the oil and gas industry to express interest in specific locations within that area. The government then releases specific areas for public tender.

The winner is the company that bids the highest for exclusive rights to lease the land not purchase for exploration and possibly development.